Homebrew PCBs

I've made a lot of tanks over the years for my circuit board fabrication company . The materials used were PVC, PE (polyethylene), and PP (polypropylene). The easiest tanks to fabricate were those made from PVC since it can be welded using a hot air welder. 

When welding PE and PP I always use nitrogen as the welding gas. My welder has a valve that allows it to idle on compressed air or switched to nitrogen while welding. I made a 750 gallon acid copper tank with PP using this method. That tank lasted more than twenty years with heavy use and never had a leak.

My plastic welder is made by Seelye Electric Company and was rather expensive but the Harbor Freight welder looks like a direct knock off for a fraction of what I paid. Buy a welder, get some scrap PVC and try it out. It's not difficult to make some very nice tanks that will last for years.  Tom


--- In Homebrew_PCBs@yahoogroups.com, Simao Cardoso <simaocardoso@...> wrote:
>
> Hi all,
> 
> The welding process was discussed before but i am unsure about plastic
> to buy. I was to buy PVC sheets and weld, is common and suitable but
> expensive. I even made myself speed welding nozzles. I always thought PE
> or PP was more expensive than PVC but actually they are less than half
> the price by square meter, being PE the cheaper. But i never had either
> those sheets side by side to test their hardness.
> 
> PE is most suitable to chemicals, lighter and stronger than PVC it only
> as a lower melting temperature but is way superior than the maximum
> needed temperature. The problem is where i am to buy it, they only stock
> PVC and PP weld. PE weld needs to be paid and wait for deliver which i
> find silly, and the minimum order is 5 times more than i need...
> 
> I am to buy 5mm HDPE sheets they are a good deal, but PP is almost the
> same price and easier to get the weld. Any advice?
> 
> BTW anyone in Europe with excess or need of PE weld?
> 
> Simão
>