Using blue foam for Ribs??? Help with some pics

[torquen]

Hey everyone, I am wanting to start researching building wings and stabs using blue foam for the ribs. I have seen a few shots over the years and have actually flown a plane using this method and it was awesome. If you have any knowlege of construction, photos, companies using this method please chime in. "Hey it will only help you out" because I'm researching this construction to bring into our models.

Also what is the actuall name for Blue foam? is it "blue foam" or is it called something else? And if you find a manufacture or place that it can be bought please add the link. Thanks for all the help!!
Garrett Morrison

[wizard]

The name of the foam is Blucore. It is hard to find now. They have started using a new type of blue fanfold that only has the plastic skin on one side. It is not as rigid as the old Blucore.

[carrid02]

Actually you can make the wing out of 1/2 in DOW foam (blue foam) that you can get from Lowes in a 4'/8' sheet. I think you are wanting to build a wing like Bob Godfrey used to built em'... except fully sheeted, not sheeted ribs?.. right?

Craig Rideout

[Xipp]

Garrett, For you needs i think this product would do better and is easy to obtain....

http://www.owenscorning.com/around/i...opinkrigid.asp

[rdgood]

Garrett,

If you are talking about designing a foamy built-up or a Giant scale built up? Their are several different kinds of foam available. Rohacell comes in blue and alot of folks use this kind of foam for the inside of glider composite wings. There is also gray cell dense foam which is even stronger than the blue Rohacell. Tim Lawlor from APEX composites was building race planes for race planes for Chip Hyde is a really good source of knowledge for the different kinds of foam and there application. I assuming that you are considering the foam use for large scale.
Hope this helps!

Ronster

[torquen]

Well what I'm wanting to do is use a foam rib in the wings instead of using ply ribs. I will be sheeting the entire wing I believe as well to get the full strength. I dont think it needs to be bagged but will be put into the jib and straped down so the bonding of the sheeting to the ribs will be there. Also I will be running full length spars and inbetween the spars will be the webbing. I think the foam will need to be about a 1/2" thick to make the ribs.

Only reason I said blue foam is I remember building some race planes using this foam because it was very dence but was still very light. You would not want to use this type of foam to make a core because its way to dence for that. Ill start looking into this stuff, and I really will look forward to everyones responces. Thanks for the help so far guys!!!
Garrett

[dmichael]

Garrett,

I designed and built a 33pct Staudacher about 8 years ago and used 1/2" blue foam for ribs. I happened to just go to Home Depot and picked up an 8X4 sheet of 1/2" blue foam insulation. The wing was very strong and straight- it still flies today (3rd owner) and he beats the crap out of it so I know it's strong.

I got the idea orginially from Wayne Ulery- his 1/3 scale laser- the original- used foam ribs and his instructions that came with the plans lay it out in an easy to understand manner.

About two years ago I built a 40pct Extra 260 and tried to use the blue foam ribs again. My very primitive and home-made foam cutting tool wasn't up to the task (the line was sagging and not giving me a straight cut) so I ended up having flyingfoam.com cut regular white foam cores instead.

The blue foam is more forgiving to cut- it doesn't seem to melt as fast- and gives a very nice smooth surface. You'll need to build some sort of jig to hold the blue foam blanks in place vertically while you cut the top of the wing- you then cut out the notches for spars, install and glue everything you can that goes on the top of the wing including the wing skins, aileron horn blocks, etc.. You'll need to cut out the holes in each rib for the phenolic and glue it into place before sheeting including any short sheer webbing from the top spar to the wing tube. Then you cut the bottom of the wing- everything is still in the jig up to this point- and repeat on bottom- cut notches for spars, glue in shear webbing, sheet the wing, etc.. Cut out and face the ailerons. Sheet the wingtip (if you want- you could skip and save weight if you are really fanatical about saving every ounce) and glue on the wood on the root- You'll use "the jig" as your cradle to keep the wings straight whil sheeting. I used light ply and made sure to tie it into the wing spars to take the force of the wing tube on the root of the wing.

Hope that makes sense.

I'll try to find some pictures and if I can find them, I'll scan the instruction sheet and pictures that Wayne Ulery included in his original plans.

Dave Michael

[dmichael]

Pictures

[torquen]

Guys just wanted to say thanks for the pics. I cant wait to start trying this method out. If you have any more shots just keep sending them because all the more is better.
Another question. What are you using for glue in order to hold the socket, leading, trailing edges and spars in place? Also the shear webbing? I think probond would work but what was used before the probond? Actually I think probond is called Gorilla glue? Thanks
Garrett Morrison

[sprice50]

Garret, I think a far easier and still light method is to foam cut the entire core and then just cut out lightening holes. A friend of mine did this with great success. You attach a thin ply template for the holes (the holes are rectangular in shape with rounded corners) on the top and bottom surface of the foam cores, and cut out the shape with a small hack-saw like hot wire cutter. This way the rest of the wing is still built as if it was a foam core wing, you can still sheet it, and a lot of the foam is removed.

I hope this helps,
Shaun