need help with stainless

[ihuntbear]

Hey people..I bought a used maple syrup evaporator...Problem is i only noticed when I got it home its soldered together with 50/50 lead solder...What can I do to get this solder out and either resolder with lead free solder or tig weld it...Cant make or sell maple syrup with lead in pans and 1000.00 to 1500.00 for new ones

 

[k0ua]

Hey people..I bought a used maple syrup evaporator...Problem is i only noticed when I got it home its soldered together with 50/50 lead solder...What can I do to get this solder out and either resolder with lead free solder or tig weld it...Cant make or sell maple syrup with lead in pans and 1000.00 to 1500.00 for new ones

Please temper my advice with knowing I am just a home/hobby welder, but this is what I would do:

take a rosebud or maybe even a good big propane torch and heat the seams of the solder joints until you can seperate the pieces. Then melt and wipe off as much of the solder as you can with a damp rag. Lightly grind with a fine grit flap disk in an angle grinder to remove all traces of the solder. Inspect carefully, then TIG it up or MIG it. Check for leaks:thumbsup:

Or another idea, cut it apart, and discard the seams and reassemble with TIG or MIG, you wind up with a smaller pan.. just and idea.

James K0UA

 

[cowski]

could it be silver soldered? heat it with a torch ,that should melt it out.then tig it .

 

[Gary Fowler]

Did you do some kind of test that said it was lead solder because I dont think lead solder of any variety will stick to stainless steel. It is most likely silver solder which should not be a problem.

 

[Baby Grand]

You can get a lead test "crayon" at the hardware store - maybe even in your grocery store. You just wipe it over the surface to be tested and if it turns pink, then there's lead in it. If not, you can enjoy your new gear and get busy cutting wood for next year's sugaring.

 

[ihuntbear]

i called the manufacture in quebec.They told me it was lead and needs to come out or buy another pan..The unit was made in 1989 and they switched over to silver or tig in 1991.A new pan is 1000.00 to 1500.00 plus shipping so i think im going to try to fix this one

 

[Shield Arc]

A new pan is 1000.00 to 1500.00 plus shipping so i think im going to try to fix this one

Well there is a perfect excuse to buy a new Tig machine, or at least a Tig rig for your SMAW machine. :thumbsup:

 

[Brad_Blazer]

If you can remove the solder, it might be a good idea to test for lead before you weld on it - you don't want to generate lead fumes.

SS will stick weld pretty good too.

 

[varmint]

In the 60's, I silver brazed a kid's bike carrier from some small diameter (1/2" OD?) SS tubing I got, and believe me, I was a rank amateur, but it went together very well, was quite strong, and never, no matter how much abuse, did a joint crack or give me trouble. I'd just disassemble and wipe the leaded solder joints, clean things up, and using an appropriate flux and brazing sticks, redo it. A simple acetylene torch should do the job.

 

[deereman75]

I have never worked with ss, but for getting off the lead, heat it up with a torch, pull it apart, then reheat the edges, and wipe it off. Just try not to burn/boil off the lead, that is not healthy. (a lead filter cartrage for a respirator might be worth it)

 

[dstig1]

Yeah you will want a properly fitted respirator with P100 filters for any serious work with lead, a well-ventilated area and keep people far away - especially kids. In vapor form like will inevitably happen from heating it to get it out, it is very toxic.

It would be far safer to cut out the joints with lead and discard them (NOT with a torch!!), then reweld/braze the unit.

 

[yomax4]

I used to sell a product that was ground up 56% silver solder in a paste. You could heat and melt out the lead and brush in the paste. Heat and it will flow and stick to the joint. Cool stuff. Or if you use a flux coated silver rod, It will push out the lead and take over the seam. You will still have some lead no matter what you do. Tig option is good as well.

 

[Jorville]

I would assume your pans are 16 gauge at the thickest, if not thinner. Stainless will warp like crazy with too much heat. Keep it as cool a possible when melting off the old solder. I would suggest silver solder. Without seeing your project I would bet a ss electrode would be too hot. And without seeing the joint tig welding could be impractical. You would need to remove all the old solder, I don't think soft solder and silver solder will mix.

 

[crazyal]

I think if it was me I would just use a .040 cut off wheel in a 4 1/2" grinder and cut the corners off (everything with any lead on it). Say like an inch in. A sheet metal shop could bend up a piece of stainless (say 1 1/2" by 1 1/2" so you have overlap) and then you could just weld in new corners. I would weld it on the inside so there's no seams to help make cleaning easier.

 

[LD1]

I think if it was me I would just use a .040 cut off wheel in a 4 1/2" grinder and cut the corners off (everything with any lead on it). Say like an inch in. A sheet metal shop could bend up a piece of stainless (say 1 1/2" by 1 1/2" so you have overlap) and then you could just weld in new corners. I would weld it on the inside so there's no seams to help make cleaning easier.

Without seeing the pan...I cannot imagine it would cost that much to get a sheet metal shop to fab you one up.

Any pics??

 

[yomax4]

After reading all these posts, I agree that you should cut the lead part out, Pay a small fee to re-bend, Weld or solder up the corners and know all is well. :thumbsup:

 

[ihuntbear]

i talked to all our sheeet metal and welding shops today..They told me to remove most of the solder. solder with lead free over the the joints..One shop told me to make new pans .they would make the pans for 5500.00 wow.I found a shop that will mig the joints today but i have to remove all the solder..so this week end i will be removing solder

 

[LD1]

I guess its my ignorance, but I dont know jack about these pans.

Any pics?? How darn big are they to be $5500 to have a shop make??

A pic is worth a thousand words ya know:thumbsup:

 

[MIKE R]

I am not a welder, but a maple syrup producer.

If you are interested here is a exert from the Ontario Maple Syrup Producers Reference Manual...

D.3.2.6 Evaporator Sap (Flue) Pan
Food Safety Hazard - Chemical lead
Most evaporators constructed before 1995 contain lead soldered seams, even those made of stainless steel. Since 1996, lead-free solder, TIG, or MIG welding has been used in stainless steel evaporator fabrication (300 series e.g. 302, 304, 316).
Because lead soldered flue pans have a larger seam area, they add more lead than lead soldered syrup pans. As the sap boils, chemical reactions occur. By the time the sap reaches the syrup pan, lead begins to precipitate out. A significant portion of this precipitated lead binds to sugar sand.The ideal solution is replacement of all lead soldered evaporators with new stainless steel models that are TIG or MIG welded. Their seams are lead-free. Smooth seams also minimize the opportunity for microbial growth. From a practical standpoint, immediate replacement of equipment may not be possible. Alternative solutions are required.
The key to reducing lead contamination from lead containing evaporators is to reduce the length of time the sap spends in them. This can be accomplished in two ways.
Boil the sap vigorously so that it moves through the evaporator in the shortest possible time. Not only will this shorten exposure to lead contamination but it may also result in lighter coloured maple syrup.
At the end of the boil, drain all sap from the flue pan into a clean food grade container.
Do not leave it in the pan overnight. Leaving partially processed sap in the evaporator allows an extended period of time for it to absorb lead. To be effective in reducing lead,food grade containers must be used for storage. Store it in a cool place.
Section D.3.2 - SUGARHOUSE PREPARATION 44
Care must be taken to avoid the pans running dry during boiling or during shutdown.Excessive heat may melt lead solder resulting in the release of more lead. It may also damage the pans.When repairs to the evaporator are needed, use only lead-free solder.Plastic or brass tubing or connectors may become overheated during processing and release contaminates into the hot sap or syrup. Only stainless steel connectors should be used at or near the evaporator.

 

[ihuntbear]

my computer wont upload pics...sorry..he told me 5500.00 for two pans..there not even fluted..rip off....I'm trying to get most of the solder out of the bottom and we'll weld 1 inch strips over the seams where the solder was..Then flip it over and do the inside with lead free...Why they used solder for these pans I'll never know..all the joints on the bottom leaks ....,well the good theing about it i got the whole unit for 1000.00.plus shipping 350.00..so I guess i can spend another 500.00 to fix it..going to make a hood and preheater while i'm at it