gi8u2racing

My Feedback: (11)

I'm trying to make some foam core wings here with a wing tube, and I know there has to be some trick to get the hole straight and the right diameter.

as722

My Feedback: (1)

You'll need two templates, one for the outside at the root and one for the inside where the phenolic ends. Cut a hole through the foam where the inner phenolic support will be and place the template. Remember that both templates must have a slot in them for the hot wire to enter. The templates can be made from lite ply as long as they are smooth so the hot wire can slide without getting caught.
Now here comes the tricki part, the template has to be slightly smaller than the phenolic or the hole will be too big. The only way to determine how much smaller is by trial and error on some scrap foam. Another tip is to use constant speed while cutting the foam or you'll get grooves.

To be honest If you've never done it or don't have the equipment you're better off getting a set of cores from them.


Albert

DMichael

My Feedback: (5)

Hey Jonathon- I couldn't tell you anything that Albert hasn't mentioned- is this a work related question? How's India?

I've done this before on stabs and on a foam ribbed wing I did on a 33% Staudacher about 8-10 years ago- it wasn't difficult.

Dave

gi8u2racing

My Feedback: (11)

For the inner template, what size is it usually? Is it like 40% of the chord in length? How thick is it? And how do you dip the bow inside the wing? The bow ends I've seen are usually 1/4" rod that's bowed to keep the wire tight, which I would think would hit the rest of the wing, unless the inner rib is very thick.

India is alright, it's a crappy place to live, but I'm trying to make the most of it. I'm ordering a 2.6m C-ARF through work, getting an apartment, and it's slowly getting better. Send an email to [email protected] and I'll put you on my list of people I am talking to in the US.

Yes, this is a work question, haha.

as722

My Feedback: (1)

Jonathan,

I'm building a carden 40% 300 right now so I'll take a picture of the wing and will measure the ply plate that supports the phenolic.


Albert

gi8u2racing

My Feedback: (11)

First off, good choice of planes, that's what I wanted to get. Second, that would be wonderful to show me all the dimensions for the wing tube stuff, thanks

gi8u2racing

My Feedback: (11)

I found these pictures in Kelly's thread:



That slot looks awfully tight to get a bow into. So now that I see how the inner foam cutting hole is, my next question is this...

What foam cutter are you guys using (or would recommend) to cut these tight areas? This will be for an industrial setup, so it's ok if it's not the cheapest solution

BTW, I'm not trying to steal from Carden, I'm working on UAV's, and just admire Carden craftsmanship

as722

My Feedback: (1)

I got hand made bows in different lengths, basically a piece of wood with two metal rods about 1/2" in diameter with the nicrome wire about a foot or so from the wood handle. Nothing fancy, I use a craftsman car battery charger to power it.


Albert

as722

My Feedback: (1)

Here's a picture of me cuting some foam ( not a very good picture ) it shows the templates and you can see the wire attached to the metal rods. Also here's a link to a company that sells a 48" bow and power supply.

http://hotwirefoamfactory.com/home.php?cat=103


Albert