Desoldering old pan

[sugardan]

Embarrassing story, put in 100 buckets this year. First boil on a tiny 3x3 arch and pan we had kicking around, went well but I ended up boiling all night around 14hrs. At 5 in the morning on my last 5 gal bucket of sap with some nice medium syrup in the last flue I squatted Down next to the wall and fell asleep like that for 20 mins. Woke up to a burnt pan.

Lesson learned sucks but moving on.

Burnt syrup came out easy with some hot water and vinegar pan is shiny new looking. Only problem is the led solder melted out of two of the dividers.

Any tips on what to do? Cold snap so no sap is running so I have a day or so to figure it out.

I'm pretty suprised all the solder melted like it did because there was still syrup in the pan, the bottom didn't warp and the burnt patches were not that bad at all. Very low temprature melting point I guess.

I was thinking of trying to de solder it somehow then re soldering it with non lead silver solder.

Will a solder pump work on a big pile of solder?

I hve been workin for large scale sugar makers for a few years and this year is the starter year for setting up the home bush here on the farm. 8000 tap potential, with an old sugar shack to boot. Planning on 2000 next year on line. Going to pick up a 5x12 grimm evaporator in a few weeks from a neighbor but that is way to large to use with my 100 taps this year.




Thanks

[harrison6jd]

i will tell you my experience. ...i had a nice used pan i bought and when i was done for the season, a friend asked to borrow it to speed up his process. he burnt it and melted the soldered joints. i tried for many hours to repair and failed. tried welding and it failed. very very frustrating. ended up junking it and getting a welded pan. welds dont melt and i dont lend out my pan. lesson learned.

[maple flats]

I think the biggest issue will be getting the joints clean to get solder to work. There will be burnt sugar in all joints and that will be super hard to get clean, if not impossible. I think you should look for another used pan or sell your sap this season and wait for the big unit on lots more taps next year.

[Joe Hillmann]

It is quite easy to solder stainless. I use lead free plumbing solder and oatey #95 lead free solder flux. You can buy it at any hardware store that sells plumbing parts.

The trick to making it stick it to very tight and very clean joints. The other trick is to use as little heat as possible. I do it with a propane torch but have been told it is much easier to not over heat the joint if you use one of the old fashioned copper bar soldering irons than you heat with a torch. When you are heating the joint the flux will start to boil and begin to brown, If it gets beyond a chocolate color, stop clean it up and start over with less heat. It would be best to practice on something other than the pan to get the hang of it.

To clean the flux you use hot water and baking soda.

[stoneslabs]

just as you and many maple-er have done, I too have had this happen to me... there was approx 1/16th of an inch from the divider to the pan along +/- 24 inches long on two of three dividers in my 30X 48" pan. end result is they ( dividers ) still work just fine!! try to add solder to the worst of it and sugar sand and crud will take care of the rest, trying to get them clean enough to re-solder is a loosing battle. good luck!

[Marc Duclos]

That is exactly what I did as of Saturday 4/4/2017. I lost my 4'x 60" syrup pan at the end of the 2016 season. Being a brick layer I figured to fix in time for the next season. Okay I told the wife I have some leaks. She asked how many? I said as many as there are stars in the sky. I am trading sap for syrup from the old gy that's got it going. www.duclosmasonry.com

[sugardan]

Thanks for the reply guys. I ended up using a torch to melt the puddles of solder the swiping it up in a rag. Removed all the excess then tried to resolder but didn't have much luck getting it to stick in the big gaps so I boiled some junky sap in it dumped that and washed it.

Boiled with it once before the freeze up made a gallon aND a half. Still functions ok doesn't flow as good but it still makes syrup so that's all that counts!

[Joe Hillmann]

If you are having problems it is much easier to solder copper to stainless than stainless to stainless. Take a piece of solid wire, stretch it just short of breaking so it straightens out. Put a lot of flux on the joint after you sand the area. Lay the wire tight in the gap so it also gets coated in flux. Then solder it. Keep the heat at least 1/2 inch away from the joint and heat it just enough so the solder starts to melt. To get the solder to start to melt you may have to use it to "scratch" the metal below the melted flux. Once you have some solder that sticks just keep touching the melted solder to the unmelted and it should melt as you go after that.

[Sugarmaker]

The trick with the copper is a good one and might work to resolder that wide joint. Good suggestion. Hope I never have to repair another soldered pan. They are a pain!
Regards,
Chris

[Joe Hillmann]

Another trick when it comes to soldering thin stainless is to heat the metal maybe an inch away from the joint till it glows red, the heat will travel to the joint without burning the flux in the joint.

It is also best to practice on a scrap piece first. At first you will swear it is impossible to make it work but once you figure it out it's pretty easy.