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Permabond 825 and 790…
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Author:  meddlingfool [ Mon Feb 12, 2024 4:29 pm ]
Post subject:  Permabond 825 and 790…
Discovered a high melting point CA. The low viscosity 825 has a melting point of 385f and the 790 high viscosity 350f.

So, this means if you had a cracky or high risk set of say Brazilian or ziricote or WHY, you could do your crack repair and flooding before bending and the glue would not melt during the bending process. In theory.

I haven’t tried it yet but I’m bringing some in as I happen to have a fair amount of Brazilian crackwood that is worth salvaging.

This may be of utility to others as well. Expensive yes, but potentially a game changer…will post results at some point.

If anyone has used this before let us know!
Author:  meddlingfool [ Tue Sep 24, 2024 1:48 pm ]
Post subject:  Re: Permabond 825 and 790…
Here’s a few pics of the glue in use. The braz had hairline fissures and cracks throughout much of it, as you can see by how much glue I used. It bent fine and all the cracks stayed filled and closed. The paper didn’t even stick to the wood after bending.

So this stuff works as advertised. Not only can you do side crack repair while the wood is flat prebending, it also opens up creative avenues for the creative types. Expensive to get into Canada but not so bad for you US people. Image
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Author:  J De Rocher [ Tue Sep 24, 2024 2:53 pm ]
Post subject:  Re: Permabond 825 and 790…
This is pretty cool. I've thought about doing wood or possibly crushed reconstituted stone inlays on the sides before bending but figured they wouldn't survive the bending. This might make that possible.
Author:  meddlingfool [ Tue Sep 24, 2024 2:56 pm ]
Post subject:  Re: Permabond 825 and 790…
It should, in theory. I thinks there’s some reason for confidence…or at least cautious optimism.
Author:  TimAllen [ Wed Sep 25, 2024 1:26 pm ]
Post subject:  Re: Permabond 825 and 790…
Thanks so much for this information, and the results of your test!

I checked into both of these adhesives on line. The low viscosity 825 is given by Permabond's site when I search on high-heat cyanocrylate. I am finding different info on Permabond 790. Maybe I've got the wrong data sheet or I'm not reading it correctly, but it doesn't show a high heat resistance. This is the data sheet on Permabond 790 I found: https://www.permabond.com/wp-content/up ... 90_TDS.pdf

Were you using 790 or perhaps a different adhesive with similar number? Or maybe the "brief" interval they mention is long enough to bend a side? That seems possible...

I'm not trying to nitpick, just wanting to verify I've understood correctly. I have some wacky-cracky BRW and I'd like to use a low-viscosity heat resistant glue before trying to bend it.
Author:  meddlingfool [ Wed Sep 25, 2024 5:47 pm ]
Post subject:  Re: Permabond 825 and 790…
That’s interesting as I had a different recollection of the data sheet. Or possibly only read the 825 sheet, as it was the sales associate that suggested the 790. I haven’t tried the 790 so maybe it’s bum info about that. I’d test it but I’ve no time. The 825 worked great though…
Author:  meddlingfool [ Sat Oct 05, 2024 6:43 pm ]
Post subject:  Re: Permabond 825 and 790…
Ok, just another little update from my frazzled mind, lol. I did in fact use the low viscosity 790 on the sides, and they held. I was pretty careful not to let the temp go above 280 and only run the heat for 15 minutes. YMMV…
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