How to stick PVC letters to Alumacore

[gus]

Any proven methods to fix letters and parts made of Sintra to Alumacore for exterior use in Northern Minnesota? The signs will be on the east and west ends of a building so they will bake in the summer and get REAL cold in the winter.
Thanks,
Ted Gustafson

[bleeth]

This sound like a job for superglue (Cyanoacrylate). I have used it for sealing rubber hosing to ceramic tile for a seal in a steam room and it worked great. Stay away from the mini-tubes at the corner store and look for a rubber gasket company or other industrial supplier. There are quite a few varieties and you want to verify the right one.
See the link below for some info from one manufacturer:

http://www.chemmer.com/p10.htm

Dave

[jseiler]

I wonder about this. CA has about zero shear strength, but lots of tensile strength. Given the sign will be hanging with the CA glue in shear and all difference in coefficient of expansion will be shear, they *may* come unglued after some time. Low temperatures also make CA brittle.

Maybe 3m 5200 marine adhesive? Flexible, made to take water abuse....it does take some time to fully cure though.

John

[Brady Watson]

I just did a job laminating 2 sheets of 1" Komacel together...and the results were less than desirable. (4 sheets total ~ 2 sets of 2pcs 1" X 4 X 10') I called Kommerling and asked what they recommended. They did not know & told me to call IPS (WeldOn)...IPS really didn't know, but suggested that I use the 1001 Weld-On product because it had a 15min open time. I laminted the pieces, vacuum bagged together and let it sit for about 6 hrs...The customer called me to tell me that after they ran it thru the paint booth/oven, the adhesive failed...Not something that I wanted to hear, but he knew it was an 'experimental' job. I'll never glue this stuff again! Next time, it'll get pre-glued and I will just cut it. FYI - Epoxy was a joke on this stuff...I did several tests and put each glue-up in the vice and smacked with a rubber mallet. Only the PVC cement worked.

Plumbing cement worked well on smaller pieces, but not larger ones since it was still wet after several days on the inside. 5200 might work...but you are not going to get a thin glue line, which was a concern because these panels were v-carved...not sure if you can paint 5200 and if the paint will look different at the glue line. My guess is it might not be such a good idea if you have to paint where the 5200 would be exposed...the surface sheen would surely be different.

Next time, I am going to strongly recommend Trupan. You can get it up to 50mm and while it requires several epoxy coats to totally weather-proof it, it responds well to all standard woodworking adhesives & methods.

-B

[btk]

I Have used Bond & Fill PVC adhesive extensively and it works great.
http://www.komatrimboards.com/companion/bondandfill.htm
I have mainly used for PVC to PVC applications, hwoever it says in the specs that it is good for wood, metal, etc. Comes in two part tube, that requires special caulking gun.
I have not tried in a oven.

Brian

[Brady Watson]

Brian,
That burns me up that Kommerling didn't bother to mention that they even had the product you mention...Doesn't anybody know how to do their job anymore beside ShopBotters ???

-B

[btk]

Brady,

The Bond & Fill is a seperate company that several of the Cellular PVC companies after-market, so it really is not a Koma product.
I buy it directly at the lumber yard as Bond&Fill.

From the Bond&Fill website:
Bond&Fill™ STRUCTURAL™, a two-part acrylic structural adhesive/filler that is exceptionally strong and durable. It's 100% waterproof, has shear strength of up to 3,412 psi, is solvent free and has a high UV resistance. It is also sandable and paintable.

Brian

[sam_harbold]

Bond & Fill will handle the heat. We use it all the time to laminate PVC togeather. We then run it through a molder, heat it to 300deg then form it around a template. When we are finished the glue line is just as tight as when we started.

Sam Harbold

[Brady Watson]

Thanks for the tip Sam. Wish I knew 3 weeks ago!!! (would have helped if I actually asked...)

-B

[tim_whitcher]

Since you are attaching two disimilar substrates to each other, I would use clear silicone adhesive, tabbing the letters first with double faced tape to hold them in place until the silicone sets.

[gus]

Tim, That was the same advice Joe C. gave me I have gone that route. I have just been watching here to see if anyone was going to come up with a direct recomendation on what works. You win.

[superior]

Ted, we have bonded dis-similar materials together for the last 20 years with 3M's VHB. It is a double stick tape, with different adhesive qualities. Your dealer can explain them to you, or check out their website. I can document one job in particular we installed 18 years ago in May. We assembled some enter/exit signs with VHB. We have experienced no failures on them. They are as tight as the day we installed them. Also, Sundowner Trailers, one of the country's biggest manufacturer of stock trailers, is about 45 miles from us. They assemble almost ALL parts of the trailers with VHB. Welding is kept to a minimum, as they are all aluminum. That is quite a testimony, in my opinion.
We keep two styles in the shop, one is very thin, the other has a foam pad with it, about .0625" thick. We use the thicker one to bond objects together than are not smooth on the faces.
Hope this helps. By the way, we keep a couple of cases of 100% Silicone around too. It does every thing well, but sometimes is a bit slow to dry, especially when hanging something on a vertical surface.
Doug

[gus]

Thanks for the info Doug. Makes me feel better about the way I did it.

I used a bit of silicone and some 3M 9473 VHB tape to hold things in place till the silicone dryed. Between the two I figure it should do it. Time will tell. They use 3M VHB tape to hold some of the wing parts on airliners so it should be able to take Minnesota weather just holding letter on a sign that isn't going 500 MPH.