jim.thornton

I'm 6 to 7 years out of the hobby and just getting back into it. When I left, I had a Chipmunk that I had started to build. I have the stab/fin, rudder and elevators done. I had the right side wing 1/2 done when my father in law crushed it. Since I got out of the hobby for a while, I wasn't too worried about it thinking that I would always finish it "later" (replacing the wing parts).

I've just taken an inventory of the parts in my kit. I can easily replace the wing parts needed but after further examination, I noticed that all of the PLYWOOD parts are warped (e.g. fuselage sides and top, firewall, spar/joiners, etc).

Quesiton: I think that I should probably scrap the kit because of the warped parts. Or, can you use them? (I'd imagine not but I have only ever built 1 model before).

What should I do with this?

gadix

My Feedback: (2)

well it depends how bad is it
i mean if u try to put some force with your hand or finger will the wood/ply can take it?

you can reinforce the weak parts that you have with some 2nd layer of ply or fiberglass and epoxy for reinforcment

chipmonk is a great model try to do the max

bigtim

My Feedback: (13)

it really doesn't take much to reproduce parts if you have the pieces to use for templates, a good scroll saw really comes in handy for cutting plywood parts out

gadix

My Feedback: (2)

is pepole still up in SF?
here in israel it's 0913 morning

yep
this kind of sawing machine will help for sure....i wish i had one too

bigtim

My Feedback: (13)

sure its only 12:00 midnight

outdoorhunting

If the parts you are using for templates are warped,how are you going to get a straight plane?? The "Chippy" is a great flying plane. However,as with any plane, I think it could be a major handfull if you build it "crooked". You can still find the kits on the Bay & RCU. Do yourself a favor & replace the defective materials. You'll be glad you did. Good Luck!!

cd_webb

My Feedback: (6)

Warped ply fuse sides are NOT good. I've just had some recent experience here. I suggest you take the warped parts, trace a pattern (just to be safe) and dampen and straighten as you build. I can promise you it'll be a handful, but what have you got to loose? You'll be able to tell if the built fuse is straight when you're done. If not, get your tracings and plywood and cut some pieces that are straight. I make it sound simple, don't I?

MinnFlyer

My Feedback: (4)

If this is the Goldberg Chippy, don't worry about the warped plywood parts. The palne is designed so that when the parts interlock, they will hold each other straight.

jim.thornton

Hmmm... It seems as though there are some mixed feelings here.

If I replace just my wing parts that were crushed it will cost me about $32. The plywood parts will cost me about $36 (assuming I haven't missed anything.

Maybe I should try the scroll saw thing. I think a friend of mine has some.

Does anyone know of any place that I can buy just the wood sheets that I need so that I can cut the parts myself?

bigtim

My Feedback: (13)

Sig and Bud Noosen are providers of model aircraft plywood,not sure about a local supplier, but any good quality ply in the thickness needed will work in a pinch, I have used both brands there pretty high quality.

NM2K

My Feedback: (14)

Psssst!

Replace the "lite ply" with veneer/door skins that you can buy at Lowes/Home Depot. No one will notice until you take off the wing and let folks see your finished interior. <G>

Ask for seconds and you'll get by spending even less money.


Ed Cregger

jim.thornton

Are veneer/door skins heavier than "Lite Ply"?

bigtim

My Feedback: (13)

Ed is right about door skins as a inexpensive replacement for light ply, the only problem I had using it was that it doesn't like CA that well for glueing the edges, and really needs Tite Bond glues to get a good bond.

even when I used alot of glue the door skins didn't hold that well using CA,it just added more weight, after I decided to try using carpenters wood glue it made a huge difference in the strength of the joint and was alot less likely to break,not too sure what the deal was with it but it seems the core material soaked up the CA quite fast and there was not enough glue to give it proper holding power on the edge .

when glueing the skins together in a sandwich(2 or more layers) to build up thickness the CA was fine since the glue was applied to the solid wood skin, otherwise it worked out great and saved a bit of $$ as well

outdoorhunting

Try Hobby Lobby.

NM2K

My Feedback: (14)

Sometimes yes and sometimes no. You have to shop wisely. I can't do better than that for an answer since there is quite a bit of variability in door skins.


Ed Cregger

multicasting

But that's just me.

Bob

sensei

I am with Mike on this, I don't think you have a real problem, but if you want new wood, then I would go on line to Aircraft Spruce & Specialty's and take a look at the Bass plywood. It is almost as strong as Birch and almost as light as light ply.

Bob

Campy

My Feedback: (1)

For a supplier for the plywood, I suggest Lonestar balsa (yes they are back in business from the fire) http://www.lonestar-balsa.com/

For NON_STRESS plywood parts, such as fuselage formers, make your own "plywood" from balsa sheets. Just glue them together and weight them down until dry. You WILL SAVE on weight.

You do not want to use the "balsa ply" for things such as the firewall, but for fuselage formers it is great and will save weight in the tail of the plane.

As others have suggested, make patterns of the parts you need, THEN you can try straightening them by wetting them and weighting them down until dry (typically about 48 hours).

If you decide on straightening them remember to shim them so they will dry "warped" in the opposite direction. When dry, the wood will spring back some, so if they are "warped" in the opposite direction, they should spring back straight.

Jose Machado

Shop for a NEW kit

rcnutstoo

My Feedback: (13)

I'm with campy straighten by spraying with diluted amonia and weight it if you need use shims.
Sig, Bud Nosen, Balsa USA, are good. every time I've ordered from lone star the wood is warped But they're cheaper        That's my expert opinion