Anyone ever cut the outer steel shell off a bulk milk tank?

[claystroup]

I brought home a 180 gallon Delaval milk tank last night. It had been sitting outside for over 20 years and has serious rust holes on the bottom of the outer steel shell. The stainless steel inner tank and lid are perfect. I want to cut the steel shell off to make the weight manageable as it took a backhoe to lift it on my trailer. I can make a light weight stand for it to sit on once the heavy steel shell is gone. I have an air cut off wheel that I could use to cut where the regular steel is welded to the stainless. Just open to looking at other ways to do the job that may be easier. Thanks, Clay

[lmathews]

Unless you have a set of torches.When I worked construction in the cheese plants we would have to demo old steel shell silos and would use a small orifice torch tip.Cut right where the two metals come together.

[lpakiz]

Your air compressor will work pretty hard to supply enough air for that job.
You might consider a cut-off wheel on a 4 inch ELECTRIC right-angle grinder. Our local Menards had them (Black and Decker) for around $20, so I bought 4 of them. Now I don't even have to change wheels from grind to cut to masonry, etc.

[Sugarmaker]

Delval tanks are different style than the four dari-kool units I have done. Dari-Kool tanks are rectangular and lower profile. They were ice bank machines and were triple walled. Sure makes a much lighter usable sap tank. If your tank is round bottom, maybe make a cradle from wood or steel to position it. As mentioned I would recommend a 4-1/2 dia thin cut off wheel on a good Dewalt or equivalent grinder. I had all the moves down and could strip one in less than a hour. I used all the stainless from the skins for other maple projects too.
Depending on the size (gallons) two folks may be able to move it after you just have the inside liner.
Regards,
Chris

Regards,
Chris

[claystroup]

Thanks for all the ideas. I did a test cut tonight with my air cut off wheel using a 3" OD x 1/16" cut off wheel and cut a 4" section pretty quickly with my small home compressor. My brother has a big 5hp compressor that will make it go a lot quicker as I left the tank on my small trailer so I could move it easily. Thanks, Clay

[MaxJ]

Just a few ideas from cleaning metals(separating)and what works the best. Plasma cutter was the go to machine for many jobs, then came the grinder with the 4"x1/8" weld cutters and going to a cheap wheel isn't worth the time and expense. All major equipment supply shops that handle quality products will have the good ones, I use to pay $3.50-$6. for a single blade as a micro 1/8" thick blade will cut a weld like butter and last for a longtime. Go to a thicker cheaper blade and one better get a case price on the wheels because it'll be a cut and replace often.

[claystroup]

Bought (2) 4" cut off wheels for my Dewalt grinder today and in about 20 minutes tonight I cut about 1/3 of the parameter welds holding the outer steel shell on. Went way faster than my air cut off wheel. I think about 4 or 5 more cut off wheels for the Dewalt and that should finish off cutting off the steel shell. Can't wait to see what it looks like with the outer shell gone. Clay

[Sugarmaker]

Nice work Clay!
Regards,
Chris

[Tapper705]

I just picked up a 500 gallon milk tank that had a rotten bottom on the steel shell. Brought it to a sheet metal shop, they cut the outer shell off and removed it for $120. Well worth it. The best news is there was 120 lbs of copper tubing inside that I brought to the scrap yard and got $250 for. They cut the outer shell off with a grinder.:lol:

[claystroup]

I just picked up a 500 gallon milk tank that had a rotten bottom on the steel shell. Brought it to a sheet metal shop, they cut the outer shell off and removed it for $120. Well worth it. The best news is there was 120 lbs of copper tubing inside that I brought to the scrap yard and got $250 for. They cut the outer shell off with a grinder.:lol:

I wasn't as lucky as there was only about 10' of 1/2" copper tubing in my tank. Took me about 3 hours, 15 or so 4" cut off wheels and a little cutting torch work to get my outer steel shell off. Now I can lift the inner steel tank off myself. I left a small section of the steel shell on where the top lid pivot arms mount so that the opening lid would stay functional. I am going to make a cradle out of treated lumber for it to sit in with skids on the bottom so I can pull it around with my lawn tractor if needed. All in all I am very happy with my $50 purchase and will put it to work next spring. Clay