Drilling steel.

[tuolumne]

I need to create four 1-1/4" diameter holes in a scrap propane tank. The walls appear to be about 3/8" thick. What are my options? I have no tool suited to the job unless a holesaw would work with cutting oil.

 

[shvl73]

A bi-metal hole saw should work fine with slow speed and oil. Do a search on propane tanks, I've no experience in drilling one and there was alot of discussion on how to do it and if it was even safe to do at all.

 

[ultrarunner]

For what it's worth, I seen people fill the tank with water.

In the machine shop, we would purge tanks with Nitrogen prior to welding,

 

[tuolumne]

For what it's worth, I seen people fill the tank with water.

In the machine shop, we would purge tanks with Nitrogen prior to welding,

I'll try the holesaw then...these tanks have been sitting outdoors for several years. The 6 holes in the top (1" to 1-1/2" have been open, as well as the 3/4" drain hole in the bottom. Is residual gas an issue? I will be welding a bushing around the holes to accept threaded pipe. I can partially fill with water, but two of the holes would be near the bottom, so I cannot fill very deep.

Edit: These are 500 gallon tanks, so not very maneuverable!

 

[NFA Fun]

Look at renting a "mag drill" basically a small drill press with a strong electromagnetic base. Using a hole saw in a hand drill...you will be there forever. Not to mention risking damage to the hole saw.

Is torching an option as long as you are welding an insert?

 

[CATMAN]

I used to read a lot of Smokey Yunick stuff (highly regarded professional mechanic/inventor). He tells of a test with a old,empty 55 gallon gasoline barrel, that has set outside open (2 holes) for 3-5 years(if memory is correct) and he put a spark plug down into it with a long spark cable attached and iqnited it with a magneto. It BLEW up. This was to show the power of vapor. I always think of vapor when it comes to these kinds of projects. I have heard of people who pump tractor or automobile exhaust into gas tanks before they weld on them to try and remove any vapors and oxygen out of that internal space/cavity.

 

[rich_ncal]

A couple of years ago, I met someone that made and sold yard art out of discarded propane tanks, mostly the smaller 5 or 10 gallon types.

He had a special process for cleaning the tanks. I think he also partially filled the tanks with water while working on them.

He said even if the tank was empty for some time there was still propane that was embedded in the metal that came back out to the surface.

I don't know if this is true, but be careful.

 

[tuolumne]

Thanks for the quick responses.

 

[sandman2234]

I had a 350 gallon tank at my Grandmothers place when I bought it from the estate. I hooked up a heat pump, so the propane tank was dragged to the back 40 and opened at the small valve, and then I REMOVED the regulator, leaving a 2.75" hole in the tank. Fast forward 3 years, I needed to clean up some, so I grabbed a hose and filled it up with water and then proceeded to torch it into pieces. It still popped at me like there was gas still in it.
Be carefull!
David from jax

 

[john_bud]

Drop in a pound or two of dry ice. Let it evap for a while then drop in another pound It will displace all the oxygen.

jb

 

[biggerten]

Drop in a pound or two of dry ice. Let it evap for a while then drop in another pound It will displace all the oxygen.

jb

Technically, it will sublimate, going from a solid to a vapor. Evaporate is going from a liquid to a vapor.

Yawn, I must be bored to correct such a penny-enny thing.

 

[cityfarma]

Technically, it will sublimate, going from a solid to a vapor. Evaporate is going from a liquid to a vapor.

Yawn, I must be bored to correct such a penny-enny thing.

Pedants of the world unite! Our job is to educate.

Cityfarma

 

[biggerten]

G'day, mate. Tie me kangaroo down, sport.

 

[SPYDERLK]

Drop in a pound or two of dry ice. Let it evap for a while then drop in another pound It will displace all the oxygen.

jb

Cool idea. Continuous air purge works well too by preventing a buildup to ignitable concentration. Normally, correctly done drilling does not reach ignition temperature tho.
larry

 

[tuolumne]

Cool idea. Continuous air purge works well too by preventing a buildup to ignitable concentration. Normally, correctly done drilling does not reach ignition temperature tho.
larry

Are you suggesting that I could hook up the dust collector to an outlet while welding? It will move about 1400 cfm through an 8" hole. The 2" outlet would slow that down a bit.

 

[ray66v]

The whole blowing up thing aside, 2 alternate methods to a 1 1/4" drill would be:
1. A cutting torch or plasma cutter followed by a die grinder with a carbide bur.
2. Mark a circle and make a series of progressive small holes, (low speed drill with cutting oil), along the line followed by the die grinder with a carbide bur.
Both methods will be time consuming.

 

[sandman2234]

Using the dust collector might be ok, as long as your not talking shop vac.
Make sure the path of dust doesn't go thru the motor to cool it, as that is a point of ignition.
David from jax