Alupanel and HDU

[GlenP]

Hi guys. Hope everyone is well and busy. I have some 32" high letters to cut for a interior application and wondered if anyone has some opinions or tips for applying Alupanel to Corafoam HDU?? My thoughts are to either use Urathane Glue (Gorilla Glue) or perhaps just silicone them together. Of course I will sand and scuff the backside of the alupanel to give it good tooth adhersion to the hdu. Any thoughts????

[Big-Tex]

Just buy ready made Aluminum Face foam core panel or Ultra foam core.
That panel has sheet of plastic in the back balancing panel well preventing curling up. Easy to cut. You may buy polished alu brushed, chrome, gold etc.
Cheaper than HDU. and no painting edges if you like black or white. Perfect for interior.

[joe]

Glen,

I'm with Thomas about the material choices. You can purchase some very nice foam materials with laminated surfaces much cheaper. Also, Grorila glue isn't the glue to use because it expands. The aluminum products are good in some applications but painting the edges are sometimes dificult.

Gool luck with your product.

Joe

[GlenP]

I did look at that option but these 32" high letters would have ended up with a joint in the alupanel in a unfriendly spot. Gemini only uses 2 x 4 material for there letters. They are 1 1/2" thick as well. Time for some testing i guess.

[toych]

Glenn, if you have to adhere Alupanel to Sign Foam I've had good results with West system 105 with 206 hardener. It's in stock locally at Boater's world or Monaghan Lumber. Make sure to scratch up the Alupanel pretty good.

A better choice, although I haven't used it may be their G Flex, engineered for dissimilar materials and expantion rates including aluminum, wood and plastics.

Watch the video of them sawing a roto-molded kayak in half, repairing it with G Flex then throwing it off of a bridge! Fun Stuff.

D.

[GlenP]

Well I did some tests with epoxy and high grade silicone. Both adhered well but the silicone was easier to work with. I sanded the hdu and vacuumed off any dust and sanded the alupanel in both directions with 100 grit to get maximum adhesion. My test pieces where 4" x 6" in size. The silicone held so well that when I pried under it with a screwdriver it bent the alupanel up slightly at the edge but would not lift off of seperate and the hdu did not seperate either. I was expecting it to come off easier. We have had a cold week here in Ontario so I put it outside at night and brought it back in the shop during day and still passed. My application is interior....in fact it is for a one day only per year award banquet so cold should not be issue for expansion of the materials against each other. I also installed a fastener into the foam for a test. I used a 4" long 1/4-20 nut extender siliconed into the edge of the foam. I was surpised at how strong it was. We tried several times to try and get the foam to split when side stress were placed on it....prying, hammering and even inserted a 12" threaded rod for extra leverage. It never did fail. I have read allot of comments on how HDU is so hard to work with for mounting etc so I was extremely surprised how this test turned out. Please take my results as my observations and if you need to do something similar do some testing first. I usually try to test anything that I am unsure of or read on the internet to prove it to myself as we all have access to different brands of glues, silcones and materials. Just thought it was worth noting for others that may have to use these materials.
Was the first time I had cut 32" high letters as well....

Cheers all.

PS-Joe I have been reading all the posts you have been doing latley and want to say thanks for sharing your knowledge and techniques.

[joe]

Glen,

Good to see you are doing well with the sign.
How about some photo's

Just for you, I'll fabricate a HDU and Alumi panel. Once set up I'll set them outside and we'll see what happens. I'm only interested in helping sign folks not make this mistake. It's ok for interior use ONLY Since Brady suggested applying silicone in bead strings accross the panel, I'll do that also. Side by side we'll see how it comes out. It's best to get advice from someone who's actually doing what they're giving advice on. I post photo's on every process I'm selling. When I have a failure, it also gets posted.

Joe