Weldon Gurus...

[BioFarmer93]

Does anyone know if Weldon sticks to EPDM? I can test when I get home, but got an idea for something & had to ask....

[myoldyourgold]

Gus that is a loaded question not knowing where it will be used. It does stick a little if the EPDM is cleaned with acetone but because EPDM is flexible and Weldon is not any flex and it cracks or releases and peals off. I have seen both take place. Contained between to things that are not stressed by heat expansion and contraction I think it would be OK but can not be sure. To glue EPDM to EPDM there is a very good product that is a supper Glue used by gasket makers and is flexible and will never let loos without tearing the EPDM. No Gurus here. LOL

[koya1893]

Does anyone know if Weldon sticks to EPDM? I can test when I get home, but got an idea for something & had to ask....

I've stopped using the Weld On, it does not last that long and it will induce problem. I discovered this during my winterization re-built.

[myoldyourgold]

I've stopped using the Weld On, it does not last that long and it will induce problem. I discovered this during my winterization re-built.

Very interesting I have more than one reactor that has hundreds hours of run time and are open and the Weld-on is still solid as the day it was put on. I think if the media blasting is not done right then there could be a problem. It requires a very rough surface to stay put but has in my case. You can not get the stuff off easily if it is on the proper prepared surface. I have it on fairly large flat areas also and none of it has come off. The reactors have been over driven and over heated and abused in so many ways to see what problems would arise when put into someone hands that is not careful. No damage to weldon at all. Ben were your plates media blasted? None of the reactors that are open that have been running for over a year 24/7 with just minor short stops to do some tests have a problem with Weld-on.

[whear]

Hi,

Since you guys were talking about Weld-On 16, I have two questions.


Will Weld-On really not stick if the plates are sanded by hand ?

Does Weld-On need to be applied on the interior of the hole, as well as on the exterior ? By how much do you go off the hole's radius on the exterior ?

[myoldyourgold]

When I was using a different product used by dentists and had sanded plates I had a problem of it not sticking and had to sand blast the area around the ports to make it stick. When Weldon 16 was discovered by Larry I switched but was already blasting around the ports so never tried it any other way. I suspect that it needs a more aggressive rough surface than you can get with sanding. Koya has stopped using it because it came off for him so he might be a better person to answer this. I do not know if he media blasts his plates. I have not had any problem but actually I use Weld-on 1802. It is just easier to use but basically the same product. Liquid acrylic. The surface must be rough and cleaned with acetone or it will not stay on.

[BioFarmer93]

Which number is it that is the real thin stuff- not just solvent, but still has some resin in it? I'll explain the reason for my question; I'm going to build a ~3V unipolar splitter reactor that uses thin wafers of ceramic as the separator membrane thereby ducking the bleed-over problem all together. The only drawback to ceramic is that the edges weep electrolyte when they become saturated. What I want to do is pre-saturate the outer .50" perimeter of the ceramic wafers with the thin Weldon. When it's time for assembly, I would then use the thick Weldon-16 between the wafer and gasket as a micro gap filler and adhesive. I will try to find the EPDM cement also as the gas vent's integrity is dependent upon gasket sealing rather than nylon fittings.

[myoldyourgold]

Gus, the 1802 is thinner than the 16 but do not know if it is thin enough for your use. I like it because it is thinner and easier to apply then 16. Gets the job done neater and easier for me anyway. I did use 3 to clean the area but found that acetone works just as good. 1802 is thinner than PVC glue/solvent by just a bit. Hope that helps. I have a working 3 LPM splitter and it is 12% less efficient than my normal HHO reactor but there is no bleed over. I gave up efficiency for no bleed over. I would only use it to store hydrogen for other uses not in a vehicle.

[BioFarmer93]

Yes, low pressure storage is my goal also for use around the farm.. I've almost given up trying to find an affordable (12-24V) pump for compressing H2 at anything above 45psi, and it's looking like one more thing I'll have to build for myself. The plan is to route the methane from the digester and the H2 to a common low pressure reservoir then compress both together into a bank of LP tanks.

[Darrell]

Weld- on will fail if you do not sandblast the plates. I always fill in the holes on the plates and redrill to the desired size ports for the application. This leaves a ridge of Weld On the inside edge of the ports and will not peal off. If you try to paint it on then it will fail due to how thin it is applied in curtain areas of the plates. When done correctly it takes a razor blade to scrape it off and is tough as nails. D