First attempt at balsa - Corben Super Ace
- Thread starter JUSS10
- Start date
Another suggestion based on what I've read - if you're working on the full fuselage you can keep alternating left & right side, which can help keep things symmetrical once the glue dries.
JUSS10
I like Biplanes
Thanks!
So lets talk glue. I'm impatient, I dont want to be, but I am. Hence why I am using CA on this. I'm using thin CA so it flows in to the joints and sets instantly. That said, I see a lot of people using tightbond. Whats the verdict here? Does tightbond set up relatively quickly while also giving you some time I would assume? Would just like some input on this.
So lets talk glue. I'm impatient, I dont want to be, but I am. Hence why I am using CA on this. I'm using thin CA so it flows in to the joints and sets instantly. That said, I see a lot of people using tightbond. Whats the verdict here? Does tightbond set up relatively quickly while also giving you some time I would assume? Would just like some input on this.
TexMechsRobot
Posted a thousand or more times
You've basically got it already. Thin CA is the fastest and has a strong bond but it hard to control and tends to be heavier overall. Titebond II sets fairly quickly, gives a strong bond, and is lighter.
I almost always use thin CA. The trick is to make sure your pieces are flush. Thin CA doesn't fill gaps.
I almost always use thin CA. The trick is to make sure your pieces are flush. Thin CA doesn't fill gaps.
The other thing to watch for with the CA glues is they don't sand worth a darn. If I'm doing a joint that's already nice and flush, I don't mind the CA at all. If I'm doing something that I know needs to be sanded to shape afterwards, I reach for the Titebond or curse at my impatient past self when I'm making dust later.
My opinion on gluing the stringers - use Titebond. It'll sand easier and gives you time to get your fingers off the stick before the glue cures. It'll also force you to slow down on a key area that will be very visible once covered. I'm also a fan of using very thin pins to hold the stringers in place while the glue dries compared to holding a piece by hand and using CA. Holding a part *MIGHT* let you glue a piece while inducing some twist or bend in the frame, and once you start adding stringers that warp won't want to come out. If the fuselage is sitting on the work bench without extra force on it and the glue is curing slowly you could end up with a straighter finished product. Especially if you're ham-fisted like me when handling parts! 
In general I'm a fan of using Titebond type adhesives over CA for new builders, as the CA will make mistakes permanent much more quickly.
In general I'm a fan of using Titebond type adhesives over CA for new builders, as the CA will make mistakes permanent much more quickly.
I haven't tried the very thin pin method for stringers yet - I bought a special pack of them a while back, but reached for the gentle rubber bands and masking tape for my most recent build.
And by very thin pins, I think we're both talking about the size 00 ones like the link below - normal sewing pins are too thick for most stringers and split 'em.
https://smile.amazon.com/gp/product/B01DCK43NO/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
And by very thin pins, I think we're both talking about the size 00 ones like the link below - normal sewing pins are too thick for most stringers and split 'em.
https://smile.amazon.com/gp/product/B01DCK43NO/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
I got some fantastic pins from Hobby Express along with a Telemaster I ordered. Very thin, ridiculously sharp, and they've got a big head on them so they're easy to insert and remove.
JUSS10
I like Biplanes
well I got the stringers in and a few other bits on over lunch today when i ran home. Thought about the stringers for a while and this is the best I could figure how to make them all merge together. I picked up some tightbond II (though after putting them in) and plan to use it on the back where they merge together to set them up well and them hopefully sand it out smooth.
I'm getting to a point on the fuse where the plans are of much help. I have a few more nose bits that are on the plans but there wasn't any info in the plans for any sort of motor so I will have to improvise. Also don't feel like the wing mount point is going to be near string enough with just those two balsa frames. I'll need input on where to add strength to this plane.
Justin
picture with my junk warped wing:
and the rest of are of the fuse as it stands.
Oh! and the 3d printed balsa stripper from Thingiverse, this thing is awesome! Been beyond helpful!
I'm getting to a point on the fuse where the plans are of much help. I have a few more nose bits that are on the plans but there wasn't any info in the plans for any sort of motor so I will have to improvise. Also don't feel like the wing mount point is going to be near string enough with just those two balsa frames. I'll need input on where to add strength to this plane.
Justin
picture with my junk warped wing:
and the rest of are of the fuse as it stands.
Oh! and the 3d printed balsa stripper from Thingiverse, this thing is awesome! Been beyond helpful!
Cool, that balsa stripper is going to easily pay for itself many times over when you compare the cost of filament to the cost of buying balsa sticks (instead of balsa sheet to be cut into sticks).
JUSS10
I like Biplanes
modeled up the cowl this morning. going to give it a shot on the 3d printer with a wall stock of .8mm. was on the fence of printing or vac forming. I'll see how the printed cowl turns out, if I'm not happy I'll make a mold and vac form it. Going to print it from PLA first but I'll likely use ABS, HIPS, or PET once I get it right to avoid any warping with heat.
JUSS10
I like Biplanes
And... its done! benefits of having a printer on my desk at work. Quite fortunate for that!
Think I'll run another once I check the fit as there are a few things I want to change about the geometry after looking at a few photos of the real plane. Cool thing is no two cowls appear the same on real ones as they were kit planes and the builders likely made the cowl fit around their engine and plane.
Think I'll run another once I check the fit as there are a few things I want to change about the geometry after looking at a few photos of the real plane. Cool thing is no two cowls appear the same on real ones as they were kit planes and the builders likely made the cowl fit around their engine and plane.
Nice work, I wish I knew how to do that kind of design work! Is there any reason you printed it with supports instead of flipping it 90 degrees? My printing knowledge is limited...
JUSS10
I like Biplanes
No matter what it would need support, I just chose the orientation I that used the least amount and printed layers in the way I wanted the strength. If I didn't want any support on the exterior of the part, I could have flipped it 180 degrees but that would have required a large amount of support material. My final one I may do that just so its less work to finish.
I see where I went wrong, the curved section has more curve than I saw at first, and probably wouldn't print well without the support. Carry on...
JUSS10
I like Biplanes
Next is to get some more sheeting on the fuse and figure out the nose. The cowl fit pretty much perfectly though I'll need to add some small blocks of balsa to screw the cowl to.
I have a pile of T motors that are 950kv swinging a 10x5 prop. I think they are around 300w. hoping that will work for this plane. Need to figure out how to get a motor mount in yet also.
Justin
Tench745
Master member
I wish I'd seen this build sooner. I've actually started building a Corben Junior Ace. Lesser known fact: the Baby, Junior and Super ace all use the same wings. Here's plate 804, wing assembly, from the Jr Ace plans. One point of note, the wingtip bow runs from leading edge to trailing edge along the chord line, not following the top of the ribs as you've drawn/built. The style you have will theoretically give you better lift characteristics, but probably not noticeably at this size
I'm curious, can you twist your warped wing back into shape with minimal force? You'll have struts that attach past mid-span to help hold things where they belong. You could even put a bit of all-thread and a metal clevis on one end of your strut to make them adjustable for dihedral and washout.
I'm curious, can you twist your warped wing back into shape with minimal force? You'll have struts that attach past mid-span to help hold things where they belong. You could even put a bit of all-thread and a metal clevis on one end of your strut to make them adjustable for dihedral and washout.
JUSS10
I like Biplanes
Are you working on a real plane or a balsa version?
Good to see that about the wing. Not sure I'll change it at this point though as it looks ok to me.
I didn't think about being able to straighten it with the wing struts. That may actually work. It takes very little first to straighten. It was built flat, just sprung back when I was done. I know it was due to a warped plywood spar. I should have just used balsa like it said.
I'm thinking i may try and fix this wing and add a bit of bracing and see if I can get it to flatten out. Will be a good piece to learn covering on as well.
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