BlockerAviation
Legendary member
I hand prop mine lol
1/5 scale Gee Bee Model D (From foam to balsa)
- Thread starter cyclone3350
- Start date
FlyingTyger
Elite member
I have never had a problem using a starter on four-strokes up to .91. Even some 120s were ok with the starter. Bigger than that, I either hand propped or used the 24v belt reduction starter I had for our big Zenoahs.
BlockerAviation
Legendary member
The only thing I use a starter on is my saito 180 because that thing will break a finger if it backfires just right and it does that more often than I'm comfortable with. I just use that 4s powered atv starter thing that a guy converts to be an Rc started and sells. Don't know the name of it but it works really well. I try not to use it though as it scuffs up the spinners
cyclone3350
Master member
What I find amusing about this subject, is that the only hand propping experience I have, is with a full scale Cub when I went for my tailwheel endorsement. So U can imagine what my frustration level will be if this thing gives me any problems. Now that I think about it, does winding back that spring on a .049 count for anything?
Flightspeed
Convicted Necroposter
Fa 100 or something like that. So a 10cc engine.
Flightspeed
Convicted Necroposter
We put the rubber cup on a drill and it spun it no problem. But every time it back fires or hits a compression cycle it slips a bit so within seconds it starts melting the nose cone. Oh and I believe the engines a saito
cyclone3350
Master member
Made for a busy day today doing these foam core wings. Cutting them out went without a hitch, but how tedious and time consuming the prep work took. First, I had to cut out the patterns which was many. The main length is a straight wing, but the last 20% of the WS has a bit of an elliptical shape to it. This had to be done by converting the curves to straight lines & to divide this into 2 sections. Besides making the step down ribs, I had to make 2 sets of patterns, 1 for the straight cuts & then another for the final shape. I went with Hobby Lobby craft foam as it is white. This is due the translucent light color of the covering I intend to use. So here R the steps. I use 1.4" thick foam & glued them with 3m 74 spray adhesive. This stuff has excellent hold & won't delaminate in the sun like the 3m 77 has a tendency to do. Glue the halves together & get to making as perfect of a true right angle block as possible. U can see how I used drafting triangles and then made straight guides for the table wire cutter to follow on the top & bottom. I just made some strips from poster board and reinforced the edges with thin CA. This keeps the wire from burning into the cardboard & works out very well. Once the outlines of the wings R cut, basswood rib patterns pinned to the sides & let the cutting bow begin. U can see by working from back to front, it made for a perfect shape with some deviation towards the leading edge. I planned this, as I had set this up to use pre shape leading edge balsa. 3" wide balsa sheeting for the leading edge & 2" wide for the TE with 3/16" X 1/16" strips to simulate the ribs will finish this off. As far as foam cutting, I have the last wing tip & hopefully the left wing will go quickly tomorrow.
Attachments
cyclone3350
Master member
Got the right wing tip done. Now the right wing is fully cut & trimmed to shape. I still need to trim off 3/16" off the wing tip & will laminate 3 pieces of 1/16th" balsa strips around it & sand to the final shape. The foam shucks R going to come in handy when I go to sheet this thing. Very pleased as to how this worked so far. I hope I can make the other side match this one.
Baron VonHelton
Elite member
Now I want a black box fan!!
cyclone3350
Master member
Now I want a black box fan!!
It does come in handy for venting fumes out that back window.
cyclone3350
Master member
Success! I was able to cut the left wing to match the right wing perfectly!
cyclone3350
Master member
This came in the mail today. 1 week from the UK to the states. Way to go Morris Mini motors .
.
cyclone3350
Master member
Oh no! Snags, set back, & this didn't quite work out!
Was making good progress until Wednesday night. Wanted to epoxy the shaped LE on, & both my 5 & 15 min was too old to make any use of it. Yesterday, had to wait for the hobby shop to open and it is a 45 min drive. Got the LE on & noticed a slight warp from the LE. Use a little heat & bending & bent too far & snap. Glued back no problem, nice & straight. Then I went to cut a groove for the 3/8th stringer, & that's when I found that craft doesn't do this very well. It is beady in texture and tends to shred. I got it in, but I still need to groove out for the rear stringer & and 1/4" ply for the main gear wire to install. This is going to make a mess of it. I went with this foam because it is white. intended to put a 2 1/2" X 1/16" sheet on the LE and a 1 1/2 X 1/16" on the trailing edge. Then I was going to add 3/16 X 1/16" strips in between for the simulated ribs. The antique yellow Solartex, which is very translucent, would cover. With the white foam in between the ribbing, this would have looked nice & old school. I've used this foam on a smaller model with full sheeting & it worked out well. It cuts great with a hot wire & is light. The sheeting adds incredible stiffness & found it to hold out under hard aerobatics. I never thought about the way it cuts. Now, do I try and salvage this, or start over with pink foam?
Was making good progress until Wednesday night. Wanted to epoxy the shaped LE on, & both my 5 & 15 min was too old to make any use of it. Yesterday, had to wait for the hobby shop to open and it is a 45 min drive. Got the LE on & noticed a slight warp from the LE. Use a little heat & bending & bent too far & snap. Glued back no problem, nice & straight. Then I went to cut a groove for the 3/8th stringer, & that's when I found that craft doesn't do this very well. It is beady in texture and tends to shred. I got it in, but I still need to groove out for the rear stringer & and 1/4" ply for the main gear wire to install. This is going to make a mess of it. I went with this foam because it is white. intended to put a 2 1/2" X 1/16" sheet on the LE and a 1 1/2 X 1/16" on the trailing edge. Then I was going to add 3/16 X 1/16" strips in between for the simulated ribs. The antique yellow Solartex, which is very translucent, would cover. With the white foam in between the ribbing, this would have looked nice & old school. I've used this foam on a smaller model with full sheeting & it worked out well. It cuts great with a hot wire & is light. The sheeting adds incredible stiffness & found it to hold out under hard aerobatics. I never thought about the way it cuts. Now, do I try and salvage this, or start over with pink foam?
Attachments
FlyingTyger
Elite member
If you do decide to redo it with pink foam, you could brush some white paint on the areas that are exposed between the cap strips. That would hide the little bit of color you'd see through the fabric.
Tench745
Master member
Oh no! Snags, set back, & this didn't quite work out!
Was making good progress until Wednesday night. Wanted to epoxy the shaped LE on, & both my 5 & 15 min was too old to make any use of it. Yesterday, had to wait for the hobby shop to open and it is a 45 min drive. Got the LE on & noticed a slight warp from the LE. Use a little heat & bending & bent too far & snap. Glued back no problem, nice & straight. Then I went to cut a groove for the 3/8th stringer, & that's when I found that craft doesn't do this very well. It is beady in texture and tends to shred. I got it in, but I still need to groove out for the rear stringer & and 1/4" ply for the main gear wire to install. This is going to make a mess of it. I went with this foam because it is white. intended to put a 2 1/2" X 1/16" sheet on the LE and a 1 1/2 X 1/16" on the trailing edge. Then I was going to add 3/16 X 1/16" strips in between for the simulated ribs. The antique yellow Solartex, which is very translucent, would cover. With the white foam in between the ribbing, this would have looked nice & old school. I've used this foam on a smaller model with full sheeting & it worked out well. It cuts great with a hot wire & is light. The sheeting adds incredible stiffness & found it to hold out under hard aerobatics. I never thought about the way it cuts. Now, do I try and salvage this, or start over with pink foam?
It looks pretty good in the pictures.
What are you using to cut your slots? Can you hot-wire them? I've used hot piano wire to melt small grooves for various things.
Power tools might be the answer here. I've used a carbide burr in a Dremel tool, on XPS (pink foam) a number of times and I've had great luck cutting white bead-foam (EPS) on a table saw.
cyclone3350
Master member
Yeah, sometimes U just gotta walk away for a day & go back with a different perspective. I was using a method with an Exacto #2 that works real well with the pink stuff. With a straight edge, follow down the 2 lines & then back over the lines @ a 45'. The remaining triangle ridge @ the bottom can be planed out with a small chisel. Not so great with a beaded foam. I did do the rear bottom stringer with a a guides pinned @ both ends & followed through with a hot bow. worked out much better that way. Finishing up the right panel now & will post pics later. @FlyingTyger, U gave me an Idea. I laid some covering over a test sample & found that the white areas R easily painted with something close to the covering color. I think this will do better to achieving the look that I had in mind.
cyclone3350
Master member
Moving along slowly. Used some guides to hot wire the grooves for the stringers, made the cut outs for the landing gear mounts & made the cut out for the ailerons.
cyclone3350
Master member
Been finding it hard to get motivated but finally got to make some progress today. Got the balsa inserts for the aileron hinges to glue into. This is a trick I use to keep an uniform angle when doing these. I draw a line down the center & tape there to the edge of the work bench. Do some carving with an Exacto long blade. Then I finish it up with a sanding block. U can see how this works for the aileron leading edge. For the sheeting, I use 3m 78 foam spray adhesive. This is a partial sheeting with faux ribs. I mask around the area to be glued & spray away. To curve the balsa, I brush on a little distilled white vinegar on the topside. The vinegar swells the one side causing it to curve to the dry side. Carefully line up where I want it to go, & press in place. Sandwich between the foam shucks from the cutting process & weight clamp it for about 15 min. The wing tips sections will be fully sheeted & hope to knock that out tomorrow. Now to decide on the final colors. The original Gee Bee was cream & blue. I am going to use what I have make it an old school model look rather than going for scale. The darker color is what is left from my Solartex stock. Antique yellow. The lighter color is Oratex antique linen. The blue is also Oratex & left over from my VH Rascal knock off. I was going to paint the white foam with a light tan, but decided it's not worth the trouble. Hmmm... leaning towards the linen.
Attachments
FlyingTyger
Elite member
Now to decide on the final colors. The original Gee Bee was cream & blue. I am going to use what I have make it an old school model look rather than going for scale. The darker color is what is left from my Solartex stock. Antique yellow. The lighter color is Oratex antique linen. The blue is also Oratex & left over from my VH Rascal knock off. I was going to paint the white foam with a light tan, but decided it's not worth the trouble. Hmmm... leaning towards the linen.
View attachment 217073
I like the look of the linen.
Taildragger
Legendary member
similar technique to how I plan to do the cruiser. two wood spars and a slot for lights and servo wires
Similar threads
