NACA profile foam cores
 

I debated putting this here or in race prep, so feel free to move if necessary. Does anyone have good source for 70-72" wing cores? Flying Foam used to be the go-to, but have since sold the business with no explanation of who it was sold to or if its still in operation. I've checked a few other RC plan shops such as Eureka, and they only dealt with sizes up to 36" without offering them as two pieces. I'd prefer to buy vs. the DIY hot wire setup, so any help would be much appreciated.

So sad flying foam disappeared. Glad I was able to order the cores for my wing about a week before they disappeared.

Not what you are asking, but somewhat relevant and possibly interesting.

You could build a CNC router to mill out foam pieces. I've seen it done for massive scale fiberglass boat building when I was in college. I've thought about building a Mostly Printed CNC router to do this task but I don't have room nor the driving skills to utilize it at the moment. The MPCNC is made from 3D printed parts and metal conduit so the dimensions are easy to change. with a Harbor Freight Router, you could probably build on for less than $300. You could theoretically be more precise and make precise adjustments more easily.

Not only would that cost more than double the price of a pair of complete foam cores, but you'd then have to source the foam on top of it. Most of the sellers use a CNC hot wire setup for a much quicker and cleaner finish. But seeing as I'm looking at a one and done application for vacuum bagging, it really defeats the purpose.

What size and shape are you looking for?

I have a S1223 10" chord, 72" length foam core sitting here that I'm never going to use

Does it happen to have spar holes? Let me measure something this weekend and get back to you! I may have a secondary application that can use that.

That's funny, I have one of those too. S1223RTL, blue surfboard foam, 300 chord (12ins), single spar hole ~25mm/1in around 1/3 chord - still in box. I don't think my span is quite that wide though, and it is in two pieces too.

I bought a NASCAR wing so the chances of me building this one are on the wrong side of zero. But OK is much closer that AUS, so you are better dealing with fmc than me lol.

No spar hole and it’s not surfboard. I can’t remember exactly which foam it is.

CNC hot wire is not to hard to set up but I usually use my CNC to cut templates that I attach to blue foam to guide the Hotwire to make cores and forms for vacuum bagging model glider wings. The foam is cut for graphite cores and then bagged. I only do 30” long cores as I flew in a 60” class but they are easy to glue together before bagging. The only thing stopping me from bagging a 90” or 120” wing is I haven’t prepped a flat spot for bagging over 60”.

Here is a 2 meter carbon in blue foam wing from years ago. The paint was sprayed onto the Mylar before bagging so there was no finish work after it came out of the form except for cutting the wing tips and gluing in some wood to make it more durable. This is a 15-45 mph wing for heavy weather slope lift.

https://cimg4.ibsrv.net/gimg/www.mia...3f5d6426c.jpeg

I found my notes and that wing was bagged by my friend Mike and was a rubber band launch 7073 Selig airfoil. The spar is carbon tow and the layup was unidirectional carbon with a very light “finish cloth” of very light glass to make the profile more accurate. (Not that it is relevant here but I didn’t want to take credit for Mike’s work.)

A few years ago my buddy was chasing various DS records. I remember climbing up mountain sides with like 5 or 6 beautiful gliders, only to return a few hours later with 5 or 6 trash bags full of airplane scraps.

That is why I grabbed that wing out of my collection, it was one I had that was undamaged. ;) We got lots of repair practice.

FWIW, I ended up buying a different rear wing (dual element NLR wang), and am making the front using a different method. I had two inner wing mounts and two end plates plasma cut, with a pair of .049 wall spars to run through them. I will be using a two part foam to fill the void before sanding/shaping and bagging. The front is a thinner 30" chord profile, so a traditional foam core was not very practical.