Weld or silver solder?

I'd go silver braze (or silver hard solder) all the way for food service - particularly if it is more or less a "working prototype" situation.

On Wednesday, March 30, 2016 at 1:30:26 PM UTC-4, snipped-for-privacy@whidbey.com wrote: Any thoughts?

First I would post this in SEJW so Ernie will see it.

There are some fluxes protecting stainless. Ernie says they are not as good as using gas, but they do work. Here is a link to one of them.

I have not used either one. Just know they exist. And if you ever get to Seattle Pottery, you can get the chemicals to make your own. Much cheaper. I know the ingredients, but not the percentages.

Dan

The fluxes are not to be used in food service because they need to be ground or sandblasted away. But thanks anyway. I looked into these a while ago. Eric

If you want some expert technical help on silver-brazing stainless, contact Lucas-Milhaupt (Handy & Harman):

I'd call and talk to a technical expert. They've always been good for me when I was writing articles about materials and brazing.

Regarding sugaring, here's a link to a pretty thorough technical paper on the subject from EPRI:

"Effects of Sugaring on Stainless Steel Weldments"

Dealing with food and pharmaceutical welding subject, I always go straight to the experts. There is just too much half-assed and mistaken "information" out there.

Good luck!

Dan

The food service inspector I have would sh*t if she saw anythiong that didn't look stainless. There would not be any need to confuse her with facts.

Of course the water inspector is even worse. Don't get me started on this subject.

Karl

Silver brazing is frequently used in making joints in custom bicycle frames and joints can have up to about 140,000 psi strength (in torque) however this assumes very close tolerance in joint fit - .001"

- .003" is optimal. Do a google search for The Metallurgy of Brazing, by Mario Emiliani, for more information.

In addition most of the fluxes used in producing these joints are water soluble and can be washed off finished joints easily.

However. Some silver brazing filler metals contain cadmium and/or other substances that is not ideal for use in devices used to process food so a bit of research through the manufacturer's literature is best before purchasing. Harris publishes an informative catalog of their brazing fillers.

Which it sorta is right now.

I'll do exactly that. Thanks Ed. Eric

Greetings Karl, There are silver solders made for food service. Silvaloy 505 is one. So your inspector needs to be educated, or else just won't listen to anything she isn't familiar with? Hmm, maybe I need to speak to the local FDA and see what they say. Eric

That is a very good plan. Right or wrong, the inspector has to give it his/ her blessing or else you're looking at redoing it, possibly paying fines, o r other unpleasant stuff.

It's seldom productive to argue with an inspector.

I was working on a re-design of a medical product to get it CE approved. We had a meeting with my customer, me, another engineering consultant and the inspector to go over our prints before submitting units for test. The insp ector pointed out a few areas that were in need of more spacing to meet the "creepage" specs. While I was making notes, the other engineering guy star ted shouting at the inspector that the specs were bullshit and nobody could or should follow them. I don't know exactly what words were exchanged betw een him and my customer, but the guy did not return after our lunch break.. . You don't argue with the guy who is going to determine whether or not you can sell your product on an entire continent.