need help with stainless

[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