Darryl Keil Last Activity 2025-09-09 11:09 AM
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Keith Simmons

Posts: 6

Joined: 2009-06-19
Location: Big Lake, AK

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Subject : Veneering ABS pipe ----- Update ----
Posted : 2009-06-22 10:20 PM
Post #35555
I finally got my hands on some West Systems epoxy glue.I got the slow dry hardener to be sure I had enough time to assemble everything.Mixed according to directions and applied to scuffed up pipe.I then put the veneer and mesh over pipe and put in vacuum bag.After two hours,the leftover 2 oz. of glue was solid as a rock,so I figured I'd open up the bag and take a look.The glue looked as though it hadn't begun to set yet.Whats up with that!It's about 65 degrees in the shop. Is that too cool for it to set or maybe just slow it down a bit. Will it eventually set?Any ideas out there?
On another note,I did a couple samples with the Titebond cold press glue that several people said would not bond to ABS.I took a sharp knife and tried to work it up under the edge.I had to destroy the veneer to get it to let go.I don't know how it could have bonded any better.FYI

Thanks
Keith


 
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Paul Kierstead

Posts: 39

Joined: 2008-01-24
Location: Ottawa, ON

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Subject : RE: Veneering ABS pipe ----- Update ----
Posted : 2009-06-23 8:33 AM
Post #35556 - In reply to #35555
Looking at the West Systems guide to Vacuum bagging

http://www.westsystem.com/ss/use-guides/

Using the slow hardener @ room temp (70 odd), the open time can be as high as 110 minutes and the cure-to-solid time is 10-15 *hours*. You opened far too soon.

Epoxy, in mass, generates a *lot* of heat as it cures. I suspect your left-over 2oz set much faster then the bagged stuff because it was a blob and the heat it generated sped up the cure time.



 
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Darryl Keil

Posts: 1455

Joined: 2003-05-22
Location: Maine

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Subject : RE: Veneering ABS pipe ----- Update ----
Posted : 2009-06-23 8:58 AM
Post #35557 - In reply to #35555
Keith,

I've never seen West System set in two hours, at least not at the glue line. I think Paul's assessment is whats going on.

Once, many years ago before I knew better I mixed up 5 gallons of epoxy all at once. While I was stirring it with an electric I noticed the drill laboring to turn, I looked down into the epoxy and to my horror it was beginning to smoke. I ran for the door to get it outside, the drill now sticking rigidly out of the epoxy. Just as I got outside there was a loud bang and the epoxy split the pail in half, smoke pouring out.

Lesson learned, dont mix epoxy in large batches.

As far as the titebond glue sticking to the ABS. Everything I know about how PVA glues bond says plastic is not a surface this glue bonds properly to. I bet if you called Franklin Chemical Co. they would even suggest against it, but hey, if its really stuck then the ultimate test would be to let it sit for a year through a summer and winter and then see what it looks like.

I still say the epoxy is the better, safer bet.

Darryl Keil


 
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Don Stephan

Posts: 825

Joined: 2003-07-18
Location: Cincinnati, Ohio

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Subject : RE: Veneering ABS pipe ----- Update ----
Posted : 2009-06-24 6:10 PM
Post #35565 - In reply to #35557
Nosy nelly in Cincinnati has to ask - WHAT was going to need 5 gallons of mixed epoxy?


 
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Darryl Keil

Posts: 1455

Joined: 2003-05-22
Location: Maine

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Subject : RE: Veneering ABS pipe ----- Update ----
Posted : 2009-06-28 4:53 PM
Post #35581 - In reply to #35565
Nosy Nelly,

I used to run a shop in Miami years ago and we had a job in Sebring, Fl making a very large bar. The bar top, believe it or not, was diamond tread plate, like on some truck beds. We were pouring the epoxy on top of the tread plate to make a smooth, slick surface. In fact, we mixed metal flake that they use in auto finishes into the epoxy to give it a more automotive look. This was a bar associated with the Sebring race track, hence the automotive look. All a bit too glitzy for my tastes.

Darryl Keil


 
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Gerry

Posts: 8

Joined: 2008-08-10

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Subject : RE: Veneering ABS pipe ----- Update ----
Posted : 2009-06-27 9:56 PM
Post #35579 - In reply to #35555
At 65°, you should have used fast hardener. And even with the fast hardener, I'd still wait at least 8 hours. Brush a little epoxy on a scrap board and use that to know when it's cured. When the test piece seems cured, I'd still wait another hour or two. When I've vacuumed epoxy, I leave it overnight.
You really want at least 75° when using epoxy, or be prepared to wait a long time for cure.

Whatever is in a cup will cure rapidly, as the thicker quantities generate heat which speeds the cure. If you want or need a longer working time, mix in a cup, and then pour into a large tray, where the depth doesn't exceed 1/4". If you have to, you can mix in multiple smaller batches. Doing it this way, you can get an hour or two of working time no problem.

But next time, allow 12 hours in the bag. If over 80°, you may be able to get away with 6-8 hours, but it may take some trial and error to find out.

Gerry
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