Homebrew PCBs

> On Monday, May 8, 2006  4:10 am, Stefan Trethan said
> 
> Yes, the longer curing epoxy is much better. You only need to look 
> at the  
> mixing proportions, the 5 minute stuff uses 1:1 while the better 
> stuff  
> uses much less hardener. That additional hardener is material that 
> doesn't  
> do any favours to strength and chemical properties i guess.
> 
> It turned yellow first as well. Then brown, and then soft.
> 
> 24h curing is a lot of time though (with my patience ;-) ), so i'll 
> stick  
> to 5-minute epoxy for most stuff. I like the long shelf life of 
> epoxy  
> compared to other glues.
> For example that neutral curing silicone i bought not that long ago 
> for  
> the silicone paper tests - it's dead already. Doesn't cure any more. 
> The  
> acidic silicone just hardens up and you immediately see it is no 
> good any  
> more. But the neutral curing one will not harden, it stays a paste 
> (though  
> thicker and less shiny), but will not harden any more at all. So 
> that's no  
> fun at all, noticing a day after that the work was for nothing and 
> you  
> have to remove the gunk again. Learned my lesson - if it appears not 
> as  
> sticky as it used to try if it will still cure before using it!
> 
> ST


I used Goop glue to build an etching tray for my FeCl3 tank, and have 
also used it to glue handles to holding trays in both FeCl3 and HCl + 
H202 tanks. Never had any failure or leakage. Stuff will glue pretty 
much anything permanently.