Why not shear web the balsa? If you have enough thin balsa on hand you could laminate your spar on either side with thin balsa sheeting and get loads more strength out of it.
Scale Build-Off – Fred Reese 40" span RV-3
- Thread starter jhitesma
- Start date
Good point, I forgot that the plans call for sheeting the top and bottom of the wing from the LE to the rear of the spar. Just gluing up the 1/4" square to the TE sheeting stiffened both up quite nicely so I'm probably good with normal 1/4" balsa for the spars. Worst case - I just build another wing, cutting the ribs wasn't THAT bad
I've never done a wing with sheeting before so I keep forgetting how much strength it can add. The smaller planes I built as a kid didn't need the strength, and my 60" glider relied on that spruce spar and eliminated sheeting to keep things light:
Though the center on that was sheeted to give it strength where it connects to the body...
Should be making much better progress after tomorrow. Payday and I should have time to hit the LHS to pickup some more supplies.
I did get the 1/8" bits cut out last night and more of the center section glued up. Just trying to get at least a little done each night to keep myself moving forward. Once I have more wood I should be able to make progress faster
Excellent engineering questions going on here. Sheeting can lend to a lot of torsional strength but not entirely "spar" strength. I would recommend a combo of the sheeting on the leading edge and back the spar with shear webbing. Light contest balsa will be sufficient. It will add some weight but give the spar much more stiffness and be less prone to cracks on harder landings. With your semi-flat-bottom airfoil you are going to get lots of lift so a little insurance weight here, I would think, is a smart move.
Good stuff! I hadn't even though of shear webbing but that makes a LOT of sense. I don't have any contest balsa and don't think it's in the budget...but it such a small amount of wood so close to the CG I'm not really worried about the extra weight.
Found a really good discussion of the benefits of shear webbing here for anyone else who may be interested: http://www.airfieldmodels.com/infor...design/shear_webs_in_model_aircraft_wings.htm
Definitely think I'm going to go ahead and do that to help give me some more peace of mind about the spars. With the two spars in this design the webbing just makes a lot of sense since as the article above says it basically turns it into an I-beam which is really strong.
Thanks for the feedback guys!
Speaking of engineering...last night as I was making the final cuts on the two 1/8" F-4/F-5 bulkheads I suddenly worried that I may have cut them 90 degrees off. It wasn't obvious from a quick glance at the plans which way the grain was supposed to go and in cutting them I worried more about leaving enough wood on the sheet for a fuselage side than I did whether or not I had the grain going right. Just took another peek at the plans - and sure enough...they're faint but there are grain lines indicated and I did get it wrong I cut them with the grain going vertical but the plans call for it going horizontal. These two bulkheads form the front/back of the cockpit - and to be honest looking at the design and thinking about forces (both in flight and in a crash) I'm not convinced that horizontal is the best way for the grain to go on them. All the other bulkheads have the grain going vertical and that seems to make more sense to me. So not sure if I'm going to bother to recut these two or not...I'll think about it a bit longer before I do anything. I doubt it would make a big difference other than in a crash. But still, this is the kind of thing I spend a lot of time thinking about during a build - how little things like paying attention to grain direction can make a big difference in strength.
Found a really good discussion of the benefits of shear webbing here for anyone else who may be interested: http://www.airfieldmodels.com/infor...design/shear_webs_in_model_aircraft_wings.htm
Definitely think I'm going to go ahead and do that to help give me some more peace of mind about the spars. With the two spars in this design the webbing just makes a lot of sense since as the article above says it basically turns it into an I-beam which is really strong.
Thanks for the feedback guys!
Speaking of engineering...last night as I was making the final cuts on the two 1/8" F-4/F-5 bulkheads I suddenly worried that I may have cut them 90 degrees off. It wasn't obvious from a quick glance at the plans which way the grain was supposed to go and in cutting them I worried more about leaving enough wood on the sheet for a fuselage side than I did whether or not I had the grain going right. Just took another peek at the plans - and sure enough...they're faint but there are grain lines indicated and I did get it wrong
I cut them with the grain going vertical but the plans call for it going horizontal. These two bulkheads form the front/back of the cockpit - and to be honest looking at the design and thinking about forces (both in flight and in a crash) I'm not convinced that horizontal is the best way for the grain to go on them. All the other bulkheads have the grain going vertical and that seems to make more sense to me. So not sure if I'm going to bother to recut these two or not...I'll think about it a bit longer before I do anything. I doubt it would make a big difference other than in a crash. But still, this is the kind of thing I spend a lot of time thinking about during a build - how little things like paying attention to grain direction can make a big difference in strength.
Bit more gluing progress last night...
If I get back into a lot of balsa building I'd love to go with a magnet system...but for now I'll stick with what I know and go with good old T pins and a chunk of ceiling tile.
Center section is starting to come together. Need some 1/16" ply for the wing joiners before I can do much more.
Hit the LHS over lunch today and wouldn't you know it...closed for inventory Was able to get a few decent pieces of balsa at Michaels but they didn't have the ply I needed. So I'll be able to start cutting the fuselage sides tonight but will have to get back to the LHS tomorrow to see if they have the ply I need to continue on the wing center. I did determine that my smaller chunk of ceiling tile is large enough to build a wing half though so I may dig in on starting to assemble the wings since that means not having to clear off a huge section of table like I've been putting off doing.
If I get back into a lot of balsa building I'd love to go with a magnet system...but for now I'll stick with what I know and go with good old T pins and a chunk of ceiling tile.
Center section is starting to come together. Need some 1/16" ply for the wing joiners before I can do much more.
Hit the LHS over lunch today and wouldn't you know it...closed for inventory
Was able to get a few decent pieces of balsa at Michaels but they didn't have the ply I needed. So I'll be able to start cutting the fuselage sides tonight but will have to get back to the LHS tomorrow to see if they have the ply I need to continue on the wing center. I did determine that my smaller chunk of ceiling tile is large enough to build a wing half though so I may dig in on starting to assemble the wings since that means not having to clear off a huge section of table like I've been putting off doing.
And this is why I'm not a fan of my LHS
No CA kicker, only tiny bottles of thin CA (great selection of thick and medium but thin is what I wanted) with high prices on them. Only epoxy was finishing resin or 5 minute - I really need some 30 minute or 1 hour for another project. They did have the blind nuts for my landing gear for only $0.99 so that was nice, but no matching screws to go with them. Their balsa selection was worse than Michaels and no better quality at higher prices...no pieces wider than 3" while Michaels at 4" wide pieces. They did have 3/32" but I need 4" wide - 3" won't cut it and Michaels didn't have 3/32". They did have 1/16" ply - but only in 6x12 and I probably need at least 12x12 maybe more given how much 1/16" ply is in these plans...and they wanted $7 for that 6x12 sheet (sticker on top of the original $3.99 price) a sheet which was hanging from a glued on hanger and was pretty badly warped They did have the 1/8" brass tube I need for the tail gear but it was $4 even though I only need about an inch of the 36" piece (guess I'll have more for the future) and they didn't have any hard aluminum or brass sheet. No 2" wheels and no good 1" wheels. No 3/32" ply.
There were three other guys in there looking for plane stuff today and they left empty handed. One was looking for "something that will do good high alpha and is RTF or bind and fly since I don't have a shop in my RV but have my TX with me and want to fly while I'm here" The other were looking for parts to build with and what they needed just wasn't there.
I really want to support the place but every time I go in there it's the same deal. If you aren't looking for something from Horizon or the small selection of DuBro they carry you're out of luck - if they do have what you want it will be 2-4x higher priced than other places usually carry it for.
They're mostly a car/truck place - 80% of their shop is taken up with car stuff and over half their building is dedicated to their indoor track. But today there was 1 person in there looking for car stuff and 4 disappointed customers looking for flight stuff. When my wife went in there shopping for me for Christmas the owner told her they don't support quad builders because "those guys don't support us because we don't carry the stuff they need so we're not interested in supporting them". What? How the heck are we supposed to support them if they don't carry the stuff we need?!
So looks like I'm going to have to place an order for wood. I did get one piece of overpriced mostly warp free 1/16" that I was able to get my wing joiners cut from so I should have all I need to build up my wing this week at least. But still. Just so disappointed with my local shop every time I go in there. I was feeling bad for them that hobby lobby is coming to town...but honestly I'm feeling less and less bad about it for them each time I go in there
No CA kicker, only tiny bottles of thin CA (great selection of thick and medium but thin is what I wanted) with high prices on them. Only epoxy was finishing resin or 5 minute - I really need some 30 minute or 1 hour for another project. They did have the blind nuts for my landing gear for only $0.99 so that was nice, but no matching screws to go with them. Their balsa selection was worse than Michaels and no better quality at higher prices...no pieces wider than 3" while Michaels at 4" wide pieces. They did have 3/32" but I need 4" wide - 3" won't cut it and Michaels didn't have 3/32". They did have 1/16" ply - but only in 6x12 and I probably need at least 12x12 maybe more given how much 1/16" ply is in these plans...and they wanted $7 for that 6x12 sheet (sticker on top of the original $3.99 price) a sheet which was hanging from a glued on hanger and was pretty badly warped
They did have the 1/8" brass tube I need for the tail gear but it was $4 even though I only need about an inch of the 36" piece (guess I'll have more for the future) and they didn't have any hard aluminum or brass sheet. No 2" wheels and no good 1" wheels. No 3/32" ply.There were three other guys in there looking for plane stuff today and they left empty handed. One was looking for "something that will do good high alpha and is RTF or bind and fly since I don't have a shop in my RV but have my TX with me and want to fly while I'm here" The other were looking for parts to build with and what they needed just wasn't there.
I really want to support the place but every time I go in there it's the same deal. If you aren't looking for something from Horizon or the small selection of DuBro they carry you're out of luck - if they do have what you want it will be 2-4x higher priced than other places usually carry it for.
They're mostly a car/truck place - 80% of their shop is taken up with car stuff and over half their building is dedicated to their indoor track. But today there was 1 person in there looking for car stuff and 4 disappointed customers looking for flight stuff. When my wife went in there shopping for me for Christmas the owner told her they don't support quad builders because "those guys don't support us because we don't carry the stuff they need so we're not interested in supporting them". What? How the heck are we supposed to support them if they don't carry the stuff we need?!
So looks like I'm going to have to place an order for wood. I did get one piece of overpriced mostly warp free 1/16" that I was able to get my wing joiners cut from so I should have all I need to build up my wing this week at least. But still. Just so disappointed with my local shop every time I go in there. I was feeling bad for them that hobby lobby is coming to town...but honestly I'm feeling less and less bad about it for them each time I go in there
roversgonemad
Member
Sounds like it must be a Hobbytown... Ours isn't much different. It's better than nothing and aside from balsa, since he's locked into a balsa supplier, I do try to order most things through them. I try to support local business as much as possible, but it can be frustrating when they never have what you need. On the plus side, our Hobbytown will match Tower Hobbies prices, so a lot of the time I go in with a Tower price for a great planes or Dubro part and he orders it for me at the Tower price. Plus, I save on the shipping. I have found that lately he is starting to stock a few of the things I have ordered more than once. I ordered some 12x4 glow props a while back and now he has them in the drawer. So many hobby shops are very two dimensional, e.g. cars and other land vehicles. I will say, multi-rotors are really taking off here. With all the gyro stabilized platforms out there, they are REALLY easy to fly.
Back on topic, typically for a build needing balsa I will generate a BOM and order from SIG. I have had really good results with SIG balsa.
As far as Hobby Lobby, it's more like a Michaels than a hobby shop...
Back on topic, typically for a build needing balsa I will generate a BOM and order from SIG. I have had really good results with SIG balsa.
As far as Hobby Lobby, it's more like a Michaels than a hobby shop...
I guess I'm fortunate that my LHS carries a decent selection of balsa and the prices are low enough for me to not complain (much). Wire and tube selection is decent, but when it comes to misc hardware or wheels they only stock bigger stuff that the average park-flyer would never need. I purchased a Beaver for my dad and asked for a lower price since I've bought a number of planes there and they actually gave me $30 off which was nice. But getting help there is typically a joke as there are always guys at the counter with their RC cars getting work done by the employees. I'm fine with helping the customers, but when there are three employees all working on cars and ignoring me it makes my conscious clear when I decide to order online.
Not part of a chain, it's a truely local LHS - locally owned and operated. But their main vendor for flight stuff is Horizon and that's about all they stock. Admitted their prices on things they source from Horizon are as good or better as on-line, they had props batteries and motors for my proto-x for less than I could get them off e-bay (though they don't seem to have them anymore.) But scratch building supplies...just not much selection and even their K&S bin is usually empty on the sizes of wire I need
Almost every time I'm in there someone comes in looking for quad props and they basically say they don't have any suppliers and aren't interested in finding one - then suggest amain.com or altitude hobbies on-line (or sometimes "overseas just google it".) Sure seems to me that they're turning away a lot of potential business but maybe that's just me.
I was spoiled growing up as we were only about 10 minutes away from Wings hobby in Lakewood ohio. They just closed last year (and a <shudder> vegan </shudder> restaurant is moving in to replace them Apparently the owner was ready to retire and his family wasn't interested in trying to compete with on-line and he couldn't find a buyer. Now THAT was a hobby store where I wouldn't mind paying a bit more because the service was so incredible and the selection was great. I still remember the big stacks of balsa, balsa kits, the display case and pegboard covered in RC gear I could only dream of someday affording. Isles of plastic models, kites, toys, lots of train stuff, all kinds of finishing supplies, steam engines, rockets and even lab equipment and chemicals! And that was just 1/2 the store! The other half was books and tabletop games (everything from RPG's to minature wargames to board games to strategy games and eventually even collectible card games.) http://lakewoodobserver.com/read/2014/04/01/wings-hobby-shop-we-loved-ya
Here's another article about them shutting down: http://www.cleveland.com/business/index.ssf/2014/03/lakewoods_wings_hobby_shop_clo.html In that second photo on the left side in the background I can see a small corner of the balsa kit rack still where I remember buying that first Piper Cub kit when I was a kid In the article the owner comments "There's just so little left on the shelves" so when you look at the photos keep in mind that what you're seeing is nothing compared to what they were like in their prime. He says they peaked in 1996....I think that was the last year I was in there - and I actually thought at the time it seemed like they were less busy than in the past and started to worry about their future, guess I was just there at an off time
Oh well. I also got enough 1/8" to start the fuselage - but I'll need more ply for the bulkheads before I can assemble it.
I may also end up going with some pink foam instead of balsa blocks for the wingtips and top/bottom of the front of the fuselage since I can't find 5/8", 1/2" or blocks of balsa - but did finally spot pink foam at my local home depot this week (Only in 24"x24" pieces for $6 though.)
I'm thinking about trying Balsa USA as I've heard good things about them from a couple of people and their prices look good. I was thinking about trying National Balsa but $25 minimum order and $16 shipping sounds like BUSA will have a better deal unless I wanted to stock up on more than I'll use in a few years.
Almost every time I'm in there someone comes in looking for quad props and they basically say they don't have any suppliers and aren't interested in finding one - then suggest amain.com or altitude hobbies on-line (or sometimes "overseas just google it".) Sure seems to me that they're turning away a lot of potential business but maybe that's just me.
I was spoiled growing up as we were only about 10 minutes away from Wings hobby in Lakewood ohio. They just closed last year (and a <shudder> vegan </shudder> restaurant is moving in to replace them
Apparently the owner was ready to retire and his family wasn't interested in trying to compete with on-line and he couldn't find a buyer. Now THAT was a hobby store where I wouldn't mind paying a bit more because the service was so incredible and the selection was great. I still remember the big stacks of balsa, balsa kits, the display case and pegboard covered in RC gear I could only dream of someday affording. Isles of plastic models, kites, toys, lots of train stuff, all kinds of finishing supplies, steam engines, rockets and even lab equipment and chemicals! And that was just 1/2 the store! The other half was books and tabletop games (everything from RPG's to minature wargames to board games to strategy games and eventually even collectible card games.) http://lakewoodobserver.com/read/2014/04/01/wings-hobby-shop-we-loved-yaHere's another article about them shutting down: http://www.cleveland.com/business/index.ssf/2014/03/lakewoods_wings_hobby_shop_clo.html In that second photo on the left side in the background I can see a small corner of the balsa kit rack still where I remember buying that first Piper Cub kit when I was a kid
In the article the owner comments "There's just so little left on the shelves" so when you look at the photos keep in mind that what you're seeing is nothing compared to what they were like in their prime. He says they peaked in 1996....I think that was the last year I was in there - and I actually thought at the time it seemed like they were less busy than in the past and started to worry about their future, guess I was just there at an off time Oh well. I also got enough 1/8" to start the fuselage - but I'll need more ply for the bulkheads before I can assemble it.
I may also end up going with some pink foam instead of balsa blocks for the wingtips and top/bottom of the front of the fuselage since I can't find 5/8", 1/2" or blocks of balsa - but did finally spot pink foam at my local home depot this week (Only in 24"x24" pieces for $6 though.)
I'm thinking about trying Balsa USA as I've heard good things about them from a couple of people and their prices look good. I was thinking about trying National Balsa but $25 minimum order and $16 shipping sounds like BUSA will have a better deal unless I wanted to stock up on more than I'll use in a few years.
Got everything for the wings except the shear webs cut and ready to go:
Not pictured are the parts for the center section which are also cut now.
Was hoping to do the initial glue-up on this wing tonight but ran out of time. Might get to work on it tomorrow morning...if not tomorrow evening, my wife is off so I don't have to cook dinner for a change
Also not included in that photo yet is the innermost rib, it gets mounted at an angle and I'm only gluing up the 90 degree ribs right now. Once I have both halves glued up this much I'll set the dihedral to confirm the angle the inner rib goes at. Plus the inner rib gets it's center cut out so the wing joiner can fit though - so it just has to be dealt with a bit differently.
Not pictured are the parts for the center section which are also cut now.
Was hoping to do the initial glue-up on this wing tonight but ran out of time. Might get to work on it tomorrow morning...if not tomorrow evening, my wife is off so I don't have to cook dinner for a change
Also not included in that photo yet is the innermost rib, it gets mounted at an angle and I'm only gluing up the 90 degree ribs right now. Once I have both halves glued up this much I'll set the dihedral to confirm the angle the inner rib goes at. Plus the inner rib gets it's center cut out so the wing joiner can fit though - so it just has to be dealt with a bit differently.
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Wing is coming along nicely, I made a few goofs but think I covered for them well enough. Reading through the original build article and photos the wing is kind of glossed over for the most part. Most of it is fairly standard but never having built a wing with any sheeted sections or capstrips like this before I was a bit apprehensive. And the build instructions seemed to assume building with CA as the assembly order suggested that attaching the lower front sheeting relied on the wicking of thin CA. So I dug in on wing with the attitude that I'd do my best...but not be upset if it winds up in the fire pit and I have to build another. Thankfully I don't think that's going to be the case
First thing I did was to glue the lower spar to the bottom sheeting as suggested since the back of the ribs is flat but the front is curved. I had already glued the rear 1/4" square piece to the short lower rear sheeting so those two served as my references once I pinned them down to the plans. I then trimmed the ribs individually to get them to fit "just right" and did a mockup assembly with no glue:
It all looked good so I glued the ribs in before going to bed last ngiht (no photos of that.) This morning I dug in on the sheer webs. I figured it would be easiest to install them before I put the top spar on and leave them just a hair tall then I could sand them down to a perfect fit. I installed every other web, then after they set for 30 minutes came back and did the others:
I Let it sit for a few hours then sanded them all even with some fine grit sandpaper glued to the edge of a piece of 1/8" balsa as a sanding block. Then finally glued the top spar in and the front strip. I had to cut a new front strip as the 3/8" tall one called for in the plans actually seemed just a hair short due to how I trimmed the ribs.
I've made more progress from here but don't have photos yet. Basically I added the 1/4" x 1/2" front strip (which is going to be mostly sanded away forming the LE) and then realized I had left out some of the bottom sheeting that was supposed to cover the first bay. So I cut a piece and glued it in...but this is one I'm a little nervous about. I don't have any wide enough pieces of balsa to cut that sheet in one piece. Ideally I probably should have put the seam right over the spar so the spar would help give it strength...instead the seam is right at the back of the spar. Not ideal, but I figure the plywood wing joiner will be in there and should help support it as well so I'm not overly worried.
The sheer webbing seems to have been a good call and made this much stiffer than I expected, and I expected it to be fairly stiff
The bottom cap strips are drying right now, I won't be able to sheet the top until I pick up more 1/16" balsa. Thought I had enough but made a few miscuts and poorly planned cuts (forgot to keep grain in mind...doh!) so I'm going to need at least one more sheet - probably two just to be safe. But I think I'm going to wait until I've joined the two wing halves before I apply the top center sheeting so it will be easier to install and clamp the wing joiner while it dries.
The big question I'm facing is what to do about the aileron servo(s)...and do I want to do flaps. I'd like to do flaps at least for the scale accuracy aspect....and the RV-3 flaps are simple. I don't have to decide just yet though as I don't have material to make the TE/Ailerons and will have to order some as I can't get it locally - but can't order until next weekend then will have to wait for shipping so it will probably be at least 2 weeks until I have to worry about those and I've got time to debate how to do the servo(s).
The plans call for one servo in the center with bellcranks installed on 1/16" ply on top of 1/16" sheeting in the wings. But that was in the early 80's when small servo's weren't as easily and affordably obtainable. But I'm really not sure what size servos would be appropriate. Would 9g's be ok on a build like this, or do I need to go bigger? There's about 1" of space where the servos would mount so I've got plenty of room it seems. Any feedback/suggestions on this? Two servos seems to me a lot simpler than one with bell cranks..but maybe I'm missing something. (I plan on using a 6ch RX so I'll have the option of flapperons as well if I go with two servos.)
Also - any suggestions on hinges? On my glider I used CA hinges...but can't say I was a huge fan. I do have the slotting tool laying around somewhere though so I could go that route again I assume. My LHS does have the robart hinge points that look nice...but I'm not sure if this 1/4" material is thick enough to install them safely. They also have plastic hinges but I've never used them before. I'm leaning towards doing fiberglass/doculam with paint for the finish so film/monokote hinges aren't really an option. Again it will be at least two weeks until I need to make a decision but I'd love to hear some ideas.
Ok. bottom capstrips should be ready to come off the board. Gotta get some more photos and setup for the second wing. We'll see how many of the mistakes on this one I make there too
First thing I did was to glue the lower spar to the bottom sheeting as suggested since the back of the ribs is flat but the front is curved. I had already glued the rear 1/4" square piece to the short lower rear sheeting so those two served as my references once I pinned them down to the plans. I then trimmed the ribs individually to get them to fit "just right" and did a mockup assembly with no glue:
It all looked good so I glued the ribs in before going to bed last ngiht (no photos of that.) This morning I dug in on the sheer webs. I figured it would be easiest to install them before I put the top spar on and leave them just a hair tall then I could sand them down to a perfect fit. I installed every other web, then after they set for 30 minutes came back and did the others:
I Let it sit for a few hours then sanded them all even with some fine grit sandpaper glued to the edge of a piece of 1/8" balsa as a sanding block. Then finally glued the top spar in and the front strip. I had to cut a new front strip as the 3/8" tall one called for in the plans actually seemed just a hair short due to how I trimmed the ribs.
I've made more progress from here but don't have photos yet. Basically I added the 1/4" x 1/2" front strip (which is going to be mostly sanded away forming the LE) and then realized I had left out some of the bottom sheeting that was supposed to cover the first bay. So I cut a piece and glued it in...but this is one I'm a little nervous about. I don't have any wide enough pieces of balsa to cut that sheet in one piece. Ideally I probably should have put the seam right over the spar so the spar would help give it strength...instead the seam is right at the back of the spar. Not ideal, but I figure the plywood wing joiner will be in there and should help support it as well so I'm not overly worried.
The sheer webbing seems to have been a good call and made this much stiffer than I expected, and I expected it to be fairly stiff
The bottom cap strips are drying right now, I won't be able to sheet the top until I pick up more 1/16" balsa. Thought I had enough but made a few miscuts and poorly planned cuts (forgot to keep grain in mind...doh!) so I'm going to need at least one more sheet - probably two just to be safe. But I think I'm going to wait until I've joined the two wing halves before I apply the top center sheeting so it will be easier to install and clamp the wing joiner while it dries.
The big question I'm facing is what to do about the aileron servo(s)...and do I want to do flaps. I'd like to do flaps at least for the scale accuracy aspect....and the RV-3 flaps are simple. I don't have to decide just yet though as I don't have material to make the TE/Ailerons and will have to order some as I can't get it locally - but can't order until next weekend then will have to wait for shipping so it will probably be at least 2 weeks until I have to worry about those and I've got time to debate how to do the servo(s).
The plans call for one servo in the center with bellcranks installed on 1/16" ply on top of 1/16" sheeting in the wings. But that was in the early 80's when small servo's weren't as easily and affordably obtainable. But I'm really not sure what size servos would be appropriate. Would 9g's be ok on a build like this, or do I need to go bigger? There's about 1" of space where the servos would mount so I've got plenty of room it seems. Any feedback/suggestions on this? Two servos seems to me a lot simpler than one with bell cranks..but maybe I'm missing something. (I plan on using a 6ch RX so I'll have the option of flapperons as well if I go with two servos.)
Also - any suggestions on hinges? On my glider I used CA hinges...but can't say I was a huge fan. I do have the slotting tool laying around somewhere though so I could go that route again I assume. My LHS does have the robart hinge points that look nice...but I'm not sure if this 1/4" material is thick enough to install them safely. They also have plastic hinges but I've never used them before. I'm leaning towards doing fiberglass/doculam with paint for the finish so film/monokote hinges aren't really an option. Again it will be at least two weeks until I need to make a decision but I'd love to hear some ideas.
Ok. bottom capstrips should be ready to come off the board. Gotta get some more photos and setup for the second wing. We'll see how many of the mistakes on this one I make there too
So here's the first wing half off the board:
Still have to figure out what I'm doing for servos (see post above) and still have to glue in the innermost rib - need to figure out the dihedral angle first and want the center and other section ready to go before I finish that up. Also still have to add the wingtip - not sure if I'm going to order some balsa blocks to carve that from or try some pink foam - seriously considering foam with a layer of 'glass over it to give it strength and protection against dings.
You can also see that I dented the top of the top spar some with my overly aggressive pinning...but the upper skin will cover that, also still have to add the top capstrips but waiting until I have the upper skin on which is waiting on joining the wings and me buying more balsa (I have enough to get this far with the other half but not enough for the tops.)
And of course still needs sanding and final shaping when all that's done.
But for my first wing section in 7 years and 2nd in 30 years I'm more than happy. It's straight and flat and stronger than I expected. Weight so far is <2oz which I'm very happy with.
Still have to figure out what I'm doing for servos (see post above) and still have to glue in the innermost rib - need to figure out the dihedral angle first and want the center and other section ready to go before I finish that up. Also still have to add the wingtip - not sure if I'm going to order some balsa blocks to carve that from or try some pink foam - seriously considering foam with a layer of 'glass over it to give it strength and protection against dings.
You can also see that I dented the top of the top spar some with my overly aggressive pinning...but the upper skin will cover that, also still have to add the top capstrips but waiting until I have the upper skin on which is waiting on joining the wings and me buying more balsa (I have enough to get this far with the other half but not enough for the tops.)
And of course still needs sanding and final shaping when all that's done.
But for my first wing section in 7 years and 2nd in 30 years I'm more than happy. It's straight and flat and stronger than I expected. Weight so far is <2oz which I'm very happy with.
Some dents in balsa you can remove quite easily. A drop of water on the dent followed by some gentle (?) heat from a clothes iron. I guess the water expands and forces the dent out. Your dents are pretty crisp so I don't know how well this will work. You could also fill them with balsa filler/spackle or just cover over them.
Yeah, that spar was really soft and the fibers tore so I don't think the old water heat trick will help. But - it's going to get covered by the 1/16" outer skin so I'm not really that concerned about them. That one piece of 1/4" was exceptionally soft and I was very wary of using it as a spar. But with the webbing I added as per Wilsonman's suggestion I'm not worried anymore - that I beam style structure is VERY stiff and I have no concern about the wing holding up despite the softness of that one spar. (I used the hardest of the 1/4" material for the lower spar to help compensate as well. Same with the other wing I'm working on - used the hardest piece I have for the bottom and saved the softest for the top.)
Webbing does wonders for strength. I added it to a few gliders I've built and it allowed me to build lighter than the plans called for.
Well, I had been making progress with my plan of making a little progress every night. Unfortunately this week has tossed a few curve balls at me. For those who aren't interested in a personal diversion and a bit of off-topic posting you can safely skip this post. For those who enjoy my tendency to wander off topic with completely unrelated projects that keep me from making progress and to sometimes share more than I probably should about my personal life, read on.
My 96 year old grandmother started showing signs that her body was giving out over the weekend and by Tuesday we were told not to expect her to make it through the night. She lived a wonderful long life and was ready to return to her maker so we were well prepared for it...but I still couldn't concentrate enough to work on a model knowing that I could get a phone call any minute confirming that she had passed on. Wednesday morning the inevitable came and she passed peacefully to be reunited with my grandfather. It would have been nice to have seen her one more time before she left us but I'm consoled by the knowledge that she was ready for this and we had said our goodbyes last time I visited knowing that it was unlikely that I'd get to see her again. Please don't feel obliged to share condolences - I'm not sharing this to get sympathy but only to explain why I had a sudden shift of project priority this week. While I am sad to have lost my grandmother I'm also happy that she's no longer frustrated with a life she was no longer enjoying and instead has finally been re-united with my grandfather whom she has missed dearly for nearly two decades.
Since I did't want to focus on a project that required the attention this one does - but I did want to keep myself busy I tackled a different project. One of my daughters friends fathers and I have become friends and shortly before Christmas he asked if I would be interested in helping him repair a vintage espresso machine. I was never big on coffee until about 6 years ago when I got curious about home roasting and taught myself how to roast coffee at home and found that when it's really fresh and high quality I actually do enjoy the stuff. I wound up getting a small home espresso machine at 60% off when linens and things went out of business - and I scored a high end commercial grinder worth about $1,000 for just $50 on Craigs list from someone who ran a mobile espresso business and was retiring (Apparently his wife priced it so low because he had broken the base and she considered it worthless. The damage was minimal though and the motor and burrs were in dirty but great condition so I got a heck of a steal for $50!) My espresso machine though is noisy and unreliable so while I love a great shot of espresso I tend to use my other brewing methods far more often. For Christmas my wife got me a vacuum pot which I've REALLY been enjoying.
Anyway, to bring this off topic topic that's straying even further off topic back under some kind of control the point was I said I'd be glad to take a look at his vintage machines in need of repair for him. But his family took a three week trip to Peru to visit his wife's family so we didn't get a chance to look at his machines until last week. The first one he wanted help with was a 1950's era Spanish made manual spring assisted lever machine. He had attempted to remove the piston but didn't realize how much pressure the spring was exerting and got the shaft the lever rides on jammed when it shifted as he tried to remove it. I was able to rig up a quick and dirty jig with an 8" clamp and some bits of ABS pipe and re-compress the spring and get the shaft out. But the 8" clamp wasn't large enough to fully release the spring. The next day I tackled it again and this time made a jig from some 3/4" plywood and 5/8" all thread - probably overkill but I have great respect for the energy stored in springs and erred on the side of caution:
It worked perfectly and we were able to remove the piston, replace the various seals (and repair some damage he had done trying to get the machine apart) and by the end of the afternoon we pulled some great shots off it with some Guatemalan beans I roasted the night before. He was so happy he asked if he could bring by a few more machines for me to look at. Which is what I busied myself with Tuesday night to keep my mind off my grandmothers situation.
The two machines he brought by were nearly identical twins. Both Zacconi Riviera manual spring assisted lever machines - vintage unknown and could be as old as the 70's or as recent as the 90's. One was complete except for the pressure gauge but had some leaks and the other was missing it's boiler sight glass, direct plumb fittings, and portafilter. Tuesday night I attempted to fix the leaks on the mostly complete one and was mostly successful but a leak around the sight glass remained once the machine reached pressure. Wednesday I tackled it again and was able to find different seals that solved the problem. The machine still had traces of vinegar in it from his descaling attempts - but we pulled some test shots with old stale coffee I had on hand. And I got a good chuckle when he ignored my warning that there was still vinegar in the brew water and despite his stuffed nose insisted that the shots smelled so good he had to try one - he spent the next 30 minutes trying various ways to get the taste out of his mouth
Tonight I gave the group a good cleaning and flushed the boiler and group with several tanks of fresh water Once I could no longer smell any trace of vinegar I gave it two more flushes and then pulled out some Ethiopian beans I roasted last night and had pulled shots of over lunch on my little consumer machine. He didn't have a tamper the right size for the portafilter so I had to improvise and as a result didn't get a great tamp - but was still able to pull a pretty decent looking shot:
I was still a bit nervous about the possibility of vinegar traces remaining...but took the risk and sampled it. I was rewarded with a wonderful shot that had all of the flavor of the ones I had pulled at lunch on my machine - but far more body and a remarkably velvet smoothness my little home machine just can't achieve.
I immediately texted him a photo of the shot and my evaluation - and he replied back saying that the second machine was mine to keep if I wanted it It needs a bit more work but I've found sources for all the missing bits and should be able to have it up and going for about what I'll probably be spending on this plane So I'm pretty hyped about stepping up my home espresso game
To bring this post back on topic - one side effect of this was I had to clean off my dining room table to have room to work on the espresso machines. So I've got room to cut my fuselage sides now. And tomorrow is payday so I'll be placing an order for the last of the wood I should need. The second wing is ready to be glued up and I hope to tackle that over the weekend as well.
So - not much progress this week...at least not on this project...but I'm primed to make some good progress over the next week and should hopefully soon have the rest of the materials I need to finish constructing the airframe.
I'm also still hoping someone will give me some advice on how to choose appropriate servos - at least for the ailerons - so I can finish up the wings.
My 96 year old grandmother started showing signs that her body was giving out over the weekend and by Tuesday we were told not to expect her to make it through the night. She lived a wonderful long life and was ready to return to her maker so we were well prepared for it...but I still couldn't concentrate enough to work on a model knowing that I could get a phone call any minute confirming that she had passed on. Wednesday morning the inevitable came and she passed peacefully to be reunited with my grandfather. It would have been nice to have seen her one more time before she left us but I'm consoled by the knowledge that she was ready for this and we had said our goodbyes last time I visited knowing that it was unlikely that I'd get to see her again. Please don't feel obliged to share condolences - I'm not sharing this to get sympathy but only to explain why I had a sudden shift of project priority this week. While I am sad to have lost my grandmother I'm also happy that she's no longer frustrated with a life she was no longer enjoying and instead has finally been re-united with my grandfather whom she has missed dearly for nearly two decades.
Since I did't want to focus on a project that required the attention this one does - but I did want to keep myself busy I tackled a different project. One of my daughters friends fathers and I have become friends and shortly before Christmas he asked if I would be interested in helping him repair a vintage espresso machine. I was never big on coffee until about 6 years ago when I got curious about home roasting and taught myself how to roast coffee at home and found that when it's really fresh and high quality I actually do enjoy the stuff. I wound up getting a small home espresso machine at 60% off when linens and things went out of business - and I scored a high end commercial grinder worth about $1,000 for just $50 on Craigs list from someone who ran a mobile espresso business and was retiring (Apparently his wife priced it so low because he had broken the base and she considered it worthless. The damage was minimal though and the motor and burrs were in dirty but great condition so I got a heck of a steal for $50!) My espresso machine though is noisy and unreliable so while I love a great shot of espresso I tend to use my other brewing methods far more often. For Christmas my wife got me a vacuum pot which I've REALLY been enjoying.
Anyway, to bring this off topic topic that's straying even further off topic back under some kind of control the point was I said I'd be glad to take a look at his vintage machines in need of repair for him. But his family took a three week trip to Peru to visit his wife's family so we didn't get a chance to look at his machines until last week. The first one he wanted help with was a 1950's era Spanish made manual spring assisted lever machine. He had attempted to remove the piston but didn't realize how much pressure the spring was exerting and got the shaft the lever rides on jammed when it shifted as he tried to remove it. I was able to rig up a quick and dirty jig with an 8" clamp and some bits of ABS pipe and re-compress the spring and get the shaft out. But the 8" clamp wasn't large enough to fully release the spring. The next day I tackled it again and this time made a jig from some 3/4" plywood and 5/8" all thread - probably overkill but I have great respect for the energy stored in springs and erred on the side of caution:
It worked perfectly and we were able to remove the piston, replace the various seals (and repair some damage he had done trying to get the machine apart) and by the end of the afternoon we pulled some great shots off it with some Guatemalan beans I roasted the night before. He was so happy he asked if he could bring by a few more machines for me to look at. Which is what I busied myself with Tuesday night to keep my mind off my grandmothers situation.
The two machines he brought by were nearly identical twins. Both Zacconi Riviera manual spring assisted lever machines - vintage unknown and could be as old as the 70's or as recent as the 90's. One was complete except for the pressure gauge but had some leaks and the other was missing it's boiler sight glass, direct plumb fittings, and portafilter. Tuesday night I attempted to fix the leaks on the mostly complete one and was mostly successful but a leak around the sight glass remained once the machine reached pressure. Wednesday I tackled it again and was able to find different seals that solved the problem. The machine still had traces of vinegar in it from his descaling attempts - but we pulled some test shots with old stale coffee I had on hand. And I got a good chuckle when he ignored my warning that there was still vinegar in the brew water and despite his stuffed nose insisted that the shots smelled so good he had to try one - he spent the next 30 minutes trying various ways to get the taste out of his mouth
Tonight I gave the group a good cleaning and flushed the boiler and group with several tanks of fresh water
Once I could no longer smell any trace of vinegar I gave it two more flushes and then pulled out some Ethiopian beans I roasted last night and had pulled shots of over lunch on my little consumer machine. He didn't have a tamper the right size for the portafilter so I had to improvise and as a result didn't get a great tamp - but was still able to pull a pretty decent looking shot:
I was still a bit nervous about the possibility of vinegar traces remaining...but took the risk and sampled it. I was rewarded with a wonderful shot that had all of the flavor of the ones I had pulled at lunch on my machine - but far more body and a remarkably velvet smoothness my little home machine just can't achieve.
I immediately texted him a photo of the shot and my evaluation - and he replied back saying that the second machine was mine to keep if I wanted it
It needs a bit more work but I've found sources for all the missing bits and should be able to have it up and going for about what I'll probably be spending on this plane So I'm pretty hyped about stepping up my home espresso game To bring this post back on topic - one side effect of this was I had to clean off my dining room table to have room to work on the espresso machines. So I've got room to cut my fuselage sides now. And tomorrow is payday so I'll be placing an order for the last of the wood I should need. The second wing is ready to be glued up and I hope to tackle that over the weekend as well.
So - not much progress this week...at least not on this project...but I'm primed to make some good progress over the next week and should hopefully soon have the rest of the materials I need to finish constructing the airframe.
I'm also still hoping someone will give me some advice on how to choose appropriate servos - at least for the ailerons - so I can finish up the wings.
Wow, this makes me glad I don't like coffee and have never tried espresso! I can see that "hobby" costing more than RC planes.
And for the record, I won't try espresso or good coffee for the same reason I don't want to try drugs - I'm afraid I'll like it!
And for the record, I won't try espresso or good coffee for the same reason I don't want to try drugs - I'm afraid I'll like it!
Ok, so this espresso machine has eaten more time than I expected...You'd think a project that included ingesting this much caffeine would go quicker
So no progress to report despite my hopes to have made progress on the second wing. But...I did place an order to BalsaUSA today for what should be the rest of or at least the bulk of the wood I need to complete this. They didn't have any pieces that seemed quite right for the 5/8" thick bottom of the nose and I didn't really want to carve it out of 1" material...so I decided to skip that, and the 1/2" slab on top of the nose and the wing tips and to try doing them out of pink foam instead since my local hardware stores finally have some even if it is only in small 24" square pieces. Then again, I may end up having to place another order if I overlooked something so I may end up ordering from somewhere else and getting the balsa after all.
The guy on RC Groups building this same plane from the same plans for their contest is using pink foam for the wheel pants, front cowl and top of the entire fuselage. I may do the same for the cowl - still undecided there, but I want to stick with balsa for the wheel pants.
Wish he'd update his thread...I need some more inspiration and want to see how he tackles a few things
So no progress to report despite my hopes to have made progress on the second wing. But...I did place an order to BalsaUSA today for what should be the rest of or at least the bulk of the wood I need to complete this. They didn't have any pieces that seemed quite right for the 5/8" thick bottom of the nose and I didn't really want to carve it out of 1" material...so I decided to skip that, and the 1/2" slab on top of the nose and the wing tips and to try doing them out of pink foam instead since my local hardware stores finally have some even if it is only in small 24" square pieces. Then again, I may end up having to place another order if I overlooked something so I may end up ordering from somewhere else and getting the balsa after all.
The guy on RC Groups building this same plane from the same plans for their contest is using pink foam for the wheel pants, front cowl and top of the entire fuselage. I may do the same for the cowl - still undecided there, but I want to stick with balsa for the wheel pants.
Wish he'd update his thread...I need some more inspiration and want to see how he tackles a few things
PHugger
Church Meal Expert
Sorry to hear about your Gram.
I grew up without coffee as well and have only started enjoying it for the last 15 years or so.
I'm not much for gourmet style and wouldn't know what to order in a Starbucks.
I am however slightly (OK highly) addicted to French Vanilla roast.
I believe the secret ingredient is likely narcotic.....
I like my coffee extra light and sweet with half & half of course.
My son gave me a TechniVorm Moccamaster a few years ago.
It allows you to simulate a pour over brew style.
It always gets top ratings (temp, time, etc).
While it's not as fancy as yours, I love it and would never be tempted to change.
You asked about servos. I'm not an expert, but just this morning I printed a Return Label for a DOA Hitec servo that I had ordered for my current project, a Fortis tricopter. It was on a recommended parts list, but I'll not be ordering that brand again. My son had a spare Turnigy metal gear that worked perfectly.
Best regards,
PCH
I grew up without coffee as well and have only started enjoying it for the last 15 years or so.
I'm not much for gourmet style and wouldn't know what to order in a Starbucks.
I am however slightly (OK highly) addicted to French Vanilla roast.
I believe the secret ingredient is likely narcotic.....
I like my coffee extra light and sweet with half & half of course.
My son gave me a TechniVorm Moccamaster a few years ago.
It allows you to simulate a pour over brew style.
It always gets top ratings (temp, time, etc).
While it's not as fancy as yours, I love it and would never be tempted to change.
You asked about servos. I'm not an expert, but just this morning I printed a Return Label for a DOA Hitec servo that I had ordered for my current project, a Fortis tricopter. It was on a recommended parts list, but I'll not be ordering that brand again. My son had a spare Turnigy metal gear that worked perfectly.
Best regards,
PCH
