cutting open an old air tank

[md21722]

Hi I've got an old air tank that I bought used and it had a pin hole leak. I want to cut it open to look inside. I don't have a plasma cutter. What's the best way to do it? 4.5" angle grinder with a cutting wheel? Drill a starting hole and use a sawmill?

I don't yet have a 4.5" angle grinder.. but am planning on getting one so this may push me over the edge.

 

[JohnX]

Plasma is clearly the way to go, but short of that I would drill a couple holes side by side, punch them together with a chisel, and use a Sawzall from there.

 

[old_man]

If you were up north, we could do it with my plasma. Otherwise, I would use the thin cut off wheels on a 4.5" grinder, but it is going to take a few.

I'm having a meet and greet this Saturday at my place, Drag it along and we can slice and dice it and have some brats.

 

[md21722]

Thanks! I may be able to come up. With a plasma cutter, do you still use cutoff tools and reciprocating saws for metal work? Or does the plasma fill in all those needs? Like, if you were going to cut a pipe in half, or shorten a bolt, do you use the plasma? I'd figure you'd still use the die grinders for finishing work.

 

[old_man]

I rarely use the plasma cutter. I have a lot of different tools to do metal working. I even have a water cooled hydraulic feed horizontal band saw. For shortening a bolt, I may just chuck it in the lathe. I have a vertical mill I use for a ton of stuff.

 

[xcm]

Angle grinders are the work horse of any metal shop. So much so, that you couldve cut it open in the time it took to create this thread.

 

[md21722]

I don't think angle grinders work quite that fast ;-)

One thing I don't understand is why most metal shops use electric die grinders. Is it because at 4.5" and up there there is no longer a size/weight advantage and they would simply use too much air to be cost effective?

 

[xcm]

You would be surprised, definately before you got a reply. =)
Whats wrong with electric grinders? In a shop setting i use both electric for the bigger stuff, and a smaller die grinder in like 1.5"-2" rolocks for the small detail.


Electric grinders work great, and yeah, im sure a air grinder big enough to spin a 4.5" disc is both loud and cfm hungry.

 

[old_man]

I love the roloc's and flap disks for finish work.

 

[md21722]

Thanks all. I am not experienced with this type of work. I'm sure I could do it but I appreciate the advice from more experienced folks here!

 

[Hypoid]

I don't think angle grinders work quite that fast ;-)

One thing I don't understand is why most metal shops use electric die grinders. Is it because at 4.5" and up there there is no longer a size/weight advantage and they would simply use too much air to be cost effective?

A die grinder is typically smaller, and more versatile than an angle grinder.

If you are able to make the trek to Loveland on Saturday, bring your tank and stop in Golden. I'll give you a primer on some rude and crude methods of cutting metal. If you have a favorite pair of safety glasses, bring them. If you don't have a pair of safety glasses, I have loaners, along with the basic P.P.E. for the other cutting methods mentioned in this thread.

 

[old_man]

A die grinder is typically smaller, and more versatile than an angle grinder.

If you are able to make the trek to Loveland on Saturday, bring your tank and stop in Golden. I'll give you a primer on some rude and crude methods of cutting metal. If you have a favorite pair of safety glasses, bring them. If you don't have a pair of safety glasses, I have loaners, along with the basic P.P.E. for the other cutting methods mentioned in this thread.

You're not going to do the primer cord bit are you?

 

[md21722]

I can bring an axle housing too, if anyone wants to demonstrate removing spring perches & shock mounts.

 

[Hypoid]

Better get here a few hours before you want to drive up to Loveland.

 

[md21722]

I bought a Makita 4.5" angle grinder (thanks Hypoid Mike for the referral - my buddy in Flag said to get the same!) and some 1/16" cutoff wheels. The Makita cut a huge horizontal piece out of the tank plus one entire side out of the tank off in little time. I am on cutoff wheel #2 with plenty remaining and already removed the pump base & some of the motor base. Respirator & eye protection mandatory. Good thing I put those on when I started. I could not believe the amount of dust & grit on the garage floor when I was done.