extracting a hole saw slug

[Usernam]

A finished insulated 20 gallon stainless steel tank with welded 1" diameter x 3" nipples contains the slug of a hole saw. Naturally, the slug is bigger than the nipples ID. Naturally, it is non-magnetic. It is so thick and strong that needle nose pliers twist when trying to bend it. However, after many tries it now looks like a spring washer. Grinding with a Dremel chain saw sharpening stone has only scratched the surface. Pinching with diagonal cutters only dents the edges.

The tank is worth a bunch of money.

What is the best way of getting the slug out?

Hellpp! :-)

(I have no idea how it got overlooked unless it was hanging by a "thread" during fabrication and fell off later.) just a guess...:confused::o

[Jim-Tx]

What is the tank used for? Does the slug HAVE to come out? Maybe it can just stay inside and never be a problem.

[Pangea]

Do you have room to hold it with pliers and get your tig torch to it? If so, melt enough of it to get it out.

[caldwellcpl]

I'd plasma cut it in half.

good luck!

[SidecarFlip]

...But will the plasma torch head fit in the bung hole?

Somehow, I think I'd have pre-drilled a hole in the center of the slug (don't the hole saw use a pilot hole to begin with?) and removed the slug with a suitabily bent wire fish tool prior to welding on the boss?

Prior planning beats the heck out of post grief.:rolleyes:

I think the poster is screwed.

Rattle can becomes rattle tank.

[fjk]

How big is the hole through which you have to work?

How big is the slug?

Can you get an O/A torch through the hole?
Hold it with something, heat til very very red,
then remove the torch, put through more pliers
and try to bend it
?

[Hotfoot]

I agree. We have to know how big the hole is...1", 4", etc? It would help a lot to know! :)

[Thomas Harris]

Sounds like quite a puzzle. If the tank is double wall (insulated), how did they weld the inside? I mean you hole saw through two layers of stainless, correct? If they weld a fitting onto the tank, doesn't it need welds on inside and out to fully maintain the tanks integrity. Is there no other access to this tank aside from the welded on fitting. How would one ever clean it? There must be more to the story. If you start to tear it apart through the hole, you may wind up with the whole thing, only not whole. That is, it may break apart and fall forever inside the tank. Non-magnetic, and too small to grab with anything.

[usmcpop]

... We have to know how big the hole is...

Irrelevant. ****, the last time I got a crown, the dentist and his assistant had all four of their hands in my mouth at once, and it's not that danged big.

Heat and bend or use a carbide burr to groove, then bend, depending on available access space. Sometimes you just have to "worry" things out. What's the layout and dimensions?

[SidecarFlip]

Irrelevant. ****, the last time I got a crown, the dentist and his assistant had all four of their hands in my mouth at once, and it's not that danged big.

Heat and bend or use a carbide burr to groove, then bend, depending on available access space. Sometimes you just have to "worry" things out. What's the layout and dimensions?

Sounds like a personal opinion...............

This scenario begs for more facts.... Not your mouth, the tank......;)

[usmcpop]

Yah, well, if you cut out a big plug and welded in a bung that had a 3/8" threaded hole, I'd say you have a big problema. More facts would help, yeah.

[Usernam]

Hotfoot - The bungs are 1" (four 3" nipples) and 3/4" (one NPT socket)

The tank is only 20 gallons and is now nicely wrapped in insulation and THICK vinyl.

Jim-Tx -Perhaps the slug can stay. It is just not to my liking. It is a potable water tank.

SidecarFlip - I have no idea. Funny :)

Pangea - Burning might damage more than the slug so I don't want to try.

fjk - The slug will not fit any of the openings due to the nipples.

usmcpop - The carbide burr seems like the best idea. Does anyone see any problems with trying it? If it was not so hard to hold, two flats would make it fit out of the 3/4" bung. Just don't want to damage the threads with the tool.

Thomas Harris - The steel is so strong it is really hard to bend and grind.

[caldwellcpl]

I still think plasma is the way to go. Bring it up to the hole,cut it up in little pieces, pour it out. The plasma cuts HOT and FAST and should not set insulation on fire like trying to heat and bend. If you place the tip at edge of plug, all the heat will be aimed behind into the tank.

[mcostello]

Could also cut with arc welding rod.

[old blue]

If you can coax a capscrew through the slug's hole and catch the threads with a slide hammer I bet it will come out easily.

[Usernam]

Tried heating, but by the time the tools were changed it had cooled.:mad: The tank stayed warm though for a long time due to the insulation.:)

[Roger]

Seeing as nothing else is working use it as excuse to try induction heating which also wouldn't work.

Acid drip onto slug hung on 316 SS wire to make it rust faster. Saltwater does same only slower.

[Usernam]

Could also cut with arc welding rod.

Hands shake too much to avoid arcing to bung

[Usernam]

If you can coax a capscrew through the slug's hole and catch the threads with a slide hammer I bet it will come out easily.

The steel is so thick it might damage the threads in the bung

[Thomas Harris]

Time to put a big access hole in that potable water tank. Added bonus- tank is nowcleanable. Just don't drop something bigger than the new hole into the tank!

[old blue]

Okay.
This is going to bug the heck outta me until it's solved because I know there has got to be an elegant solution.. something that doesn't involve throwing hot slag or grinding up a mess.

Tell me more about the holes.. placement and I.D.'s (including thread spec's)


I'll crack this yet.

[Usernam]

Okay.
This is going to bug the heck outta me until it's solved because I know there has got to be an elegant solution.. something that doesn't involve throwing hot slag or grinding up a mess.

Tell me more about the holes.. placement and I.D.'s (including thread spec's)


I'll crack this yet.

I'm grinding up a mess now using a Tungsten-carbide tool. There are little flakes of SS going everywhere. One half of the slug is notched half way through. It still won't bend. It is turned around in the 3/4" NPT bung now and ready to grind the other half.

Hands are too shaky now to finish so I'm taking a break to read/write this thread.

The 1' NPT nipple ports are located at 90 degrees on two sides of the tank. The 3/4" NPT port is on the top. Since the nipples are 3" long, the only tool that will work through them is a little light and a retriever, The retriever is getting a lot of use.:)

Got a (or is it some) cool ergo looong needlenose pliers at Lowes and it (or they) is (or are) good for moving the slug. A locking needlenose is holding the slug for grinding.

A slotted 1/2" carbon steel bar with a U bend is used for twisting it.

[Roger]

Your really persistent.

[Thomas Harris]

I hope there is a way to flush it out. I wouldn't want to drink out of a potable water supply with stainless shavings inside it!

[Usernam]

I hope there is a way to flush it out. I wouldn't want to drink out of a potable water supply with stainless shavings inside it!

It will be flushed for several minutes.

Some people are sensitive to the nickel in SS. (www.atsdr.cdc.gov/tfacts15.pdf)

A coffee filter will work well to look for flakes after flushing. If flakes are found, then more flushing is performed until the filter looks clean.

The good thing is that most people know not to drink DHW in old houses.

[Usernam]

Your really persistent.

It paid off. The slug is out. Ground one half part way through and the other all of the way. Then bent it in half and took it out.

Thanks everybody!

[Blacksmith]

Thank you for closing this out for us. I'm glad you got it out. Some people post for help and never come back; we don't know if they were sucessful or not.

[usmcpop]

I had a feeling you could gnaw that out of there.