I started building a P-39 I've been working on. It started life being built from FFF, but I decided to go balsa, as I prefer that over foam.

I posted the build over on RCG as there really doesn't seem to be much interest in balsa builds here, but thought I would post a heads up here in case there is any interest. There will be a plug for the Phlatboyz

Here's the thread... Just started it a few minutes ago. http://www.rcgroups.com/forums/showthread.php?t=1570681

 

Looking good Dave
Thank you for the props
Mark and Trish

 

Been making progress on the P-39...

More pics and such on the RCG thread, but here's some "teaser" pics. Attached files

 

A true work of art Dave, thank you for sharing this cool project with us!
Keep up the good work can't wait to see this one start going together.
Mark and Trish

 

THANKS guys...
I halfway thought about a foam wing, but....
* I can't get foam that thick around here, at least in the expanded bead kind. Actually the thickest EPS is 2", and the root is about 2.75", and IMO EPS would be too heavy. I went for a thick airfoil as speed won't be a problem, but I'm thinking the extra volume would be nice. Something often forgot about is volume loading. Every one thinks wing loading, but not volume.

* It would probably take me about as long, or longer to construct a foam wing as this is a one of... I framed the first panel up in about half an hour. The second one took about 20 minutes. I egg created a lot of it so even though there were extra parts, I think it went quicker as I really didn't have to worry about alignment.

* I'm fairly certain I can build a lighter built up wing than a foam one... This wing is quite a bit larger than my Kougar wing (it's only 50" and the cord & tips are about 2/3 the size. It is WAY heavier than this wing. True I haven't sheeted it yet, but that when it's all said and done, I am confident this one will be lighter.

* the top of the wing is flat, and the bottom tapers with the airfoil thickness... Not sure how I would have made the templates for a foam wing for that one.... I'm sure it could have been done, but I actually didn't consider that until I had almost all the CAD work on the wing done. Had to do some cyphering to get the tabs right. I wussed out and made the jig for the washout instead of trying to add to the tabs. It was still a real head scratcher as I had the wing upside down, and I couldn't go down into the building board.... It still didn't seem right while I was framing the panels, but once off the board, and brought together to check, they looked good. Surely don't want washin

 

Dave just saw some of the pics you posted over on the rcgroups thread, its nothing short of amazing!
You are making great progress, keep up the good work
I am posting a couple of my favorites(pics) for the announcement . I hope this drums up some of the balsa builders here as I know we get a lot of people who ask us about balsa building on the Phlatprinter and it would be great to see more of these projects. They are fantastic looking models
Thank you for letting the guys over there know about the Phlatprinter
Mark and Trish Attached files

 

I actually use Compufoil (Have version so old it came on floppy disk )I just forgot about the taper, and washout until after I modified most of the ribs, and didn't want to start over. (I always seem to forget something important when designing a plane) May have been easier to start over, but it worked out OK.

I tried to glue multiple sheets of foam to build up thickness, then wire cutting, but I had delamiantion issues. What glue do you use?

Anyway I posted more pics on the RCG thread. Nothing really CNC related, but may be some interesting pics for the foam only builders There is some foam in there.

Anywho, here is a pic of the plug I made for the canopy as it relates to the Phlatformer. Unfortunately I'll have to cut it in half to fit in the Phlatformer. I'll make the break at the roll bar ( for lack of a better term) so hopefully the glue seam will be hidden. Attached files