Roger Q.

My Feedback: (1)

Hi Guys, I used to do a lot of cutting of wings from styrofoam, and then doing a quick and dirty fiberglass cloth with resin for short life span slope soaring planes. The problem I now face is how to cut out templates. I had a whole bunch of instructions for the whole process of making foam/fiberglass wings, and now seem to have lost the part about the best way to lay out and cut out the templates. Any help would be appreciated. rww

vicman

My Feedback: (10)

I cut mine out from a plan, use spray 77 on a thin piece of aluminium or formica, bandsaw to shape and voila! You may be able to go to lowe's or home d and get a broken piece of formica for nothing.

Roger Q.

My Feedback: (1)

thanks for the info: however, what I am looking for is what size is the blank: I used to start with a rectangle of Formica longer than the paper outline of the wing, and the thickness of my foam block, and then cut top and bottom patterns out from that. is that correct????? Thanks again. What a great way to communicate is RCU. Roger

vicman

My Feedback: (10)

Yep! Thats how I do it. I usually leave a 1/4 wide by 1/2 long tang on the leading and trailing edge just to rest the wire on before I start into the actual wing. The guy who taught me had numbers written on the side of his templates so he knew where he was at on both ends, if he was even or not. If you use a dowel rod for the LE you can cut your templates on the LE to shape and burn that shape in also. It makes a nice straight cove for the rod to glue into but changes your template for burning the wing. There are a myriad of tricks for cutting foam with wire none of them wrong. Take a look at this month's Model Airplane News, there are some great ideas in there for a small electric SE5. When you trim the ends and dihedral get two cheap combination squares, set the foam on blocks above the protactor heads and run your wire down the scales, real easy.

Have fun!

JHarris-RCU

My Feedback: (4)

I want to copy a wing that is made from the traditional balsa and monokote. I have the template from the original kit. Do I just trace it and then make an aluminum template? Then cut? I am a bit lost...I understand that there are companies that will do this for you if you send them plans and a template.

Anyone know who and how to contact them?
Jim

jester1a

My Feedback: (1)

The answer is MAYBE. If it is the outline of the wing then yes, if it needs balsa over the ribs, ie capstrips or D tube sheeting, then you must add that in to make a true copy. You shouldn't have to send it out, it's not that hard to make templates- just start and it should be rather easy to get through it.

GOod Luck,

JESTER

vicman

My Feedback: (10)

Trace the rib or make a copy in a copier and glue it to the template material. Don't pay someone, try it yourself it is super easy! Check your pm.[sm=tongue.gif]

Stratotanker

My Feedback: (3)

I can do custom cuts with my CNC cutter if you are interested, it is extremely accurate and can cut spars,servo wiring tunnels, washout, sweep from a huge airfoil database.

Chris

thumbsup

Hello, everyone!

I always have spend a LOT of time polishing the templates so the wire will run smoothly. Is there a way to avoid this? - I mean, formica is better than aluminum? Or zinc sheets? or? What about having the templates laser cut out of lite ply or even formica itself? Would it work as templates? What if I glue a piece of music wire to the contour of the laser cut wood - so the wire would run over it? Laser cutting is reasonably priced in Brazil.

Anyway, a friend told me about this page the other day... check it out: www.cenece.com - it's a CNC sort of equipment for cutting foam you can build yourself - if you're into programming, etc. Neat stuff.

I found this place in Brazil that cuts foam on a CNC, but it is rather expensive. Chris, does it take too much time to program the machine or something? It's probably less than what it takes me sanding the templates, I'm sure... is it expensive there, anyway?

Best regards, my friends.
Thumbsup.

Ed Smith

It takes less than a couple of hours to trace the templates onto some 1/8 ply, cut them out and sand the edges smooth, seal with cyano. What is the problem? All of my templates are made from 1/8 ply.

Ed S

dreadnaut

My Feedback: (5)

I use 1/16 aircraft plywood. I run a bead of medium CA along the profile edge, snad it down with 400, repeat the CA then finish it down with 600. I think lite ply would be to soft, and you could actualy cut into the template.

I also space the template 1/16 inch away from the core when cutting. This keeps the template cleaner, and helps prevent *cupping* of the foam where it contacts the template.

soholingo

Ed, how long do these templates last? I thought the reason you went with the formica or phenolyic templates is because they last longer...

jay

thumbsup

Hah!
I had been cutting them out of tin sheets with big scissors![:'(][&:]
My friends are more built-up inclined, you know, so I guess I should have not reinvented the wheel.
I will try the ply+CA templates on my next project - building will start next week, most likely.

Thanks a lot!
Thumbsup.

Stratotanker

My Feedback: (3)

Thumbsup,

The price of CNC cutting depends on what you want, I base my price off of the time the machine is running. The run time will vary based on how much sweep, washout, major camber changes, spars etc The people there may just be greedy with their machine??? If you can e-mail me the wing design of what you want cut I can tell you what it would cost for me to do so you have something to compare. Drop me an e-mail if you are interested and I will tell you the measurements that I need to put your wing design into the computer, I can laser cut templates as well!

Chris

Ed Smith

I have never used anything else but plywood for my templates. I have never worn any out and I cut a lot of cores.

Ed S

soholingo

That's the answer I was looking for....

thumbsup

Chris,

Airfoil: Eppler 423 (root and tip)
Span: 71.66in (two pieces of 35.83?)
Root: 21.65in
Tip: 14.17in
Sweep: Leading edge, 6°
Washout: some 3°
Dihedro: Whateverit takes to make top flat (highest points of root and tip airfoils in line)
No spars or ailerons cut for now

By the way, I put together an excel little program to calculate basic wing planform values like area, aspect ratio, sweep, cma, given root, tip, span and longitudinal distance from root le to tip le. Just don´t know how to upload it. Anyone interested? How do I do it?

Thumbsup.

Stratotanker

My Feedback: (3)

If this is the design that you are looking for I can do it(12.5 % thick, 10% camber), I sent you a personal message with a price qoute for you to compare. I can cut the spars and wiring cutouts to your specs but ailerons will have to be cut and added by you., I can also offset the leading edge so that it is flat for a balsa leading edge(need thickness of wood used) I would need to know the sheeting thickness as well so the machine can offset the proper amount.

Chris