Bo****ks- engineering help wanted

[Pladdatoo]

I have gone and broken a stainless bolt being too heavy handed trying to extract it.

It is on a ram and any further extraction will need to be done in situ.

As you can see (from the picture of the one I was able to remove) the bolt has sheared with about 1 1/2 turns to go (it only threads in the lower section).

So, how do I get the rest of it out? As you can see it has broken off below the surface so I cant get a grip on the top of it- I suppose drilling is the only way,. What would be the most effective way?

Gripping the threaded section in the jaws of the ram might be possible but the bolt is well and truly tight in there...........

Suggestions for the stupid one!

Thanks you in anticipation.

PladdaView attachment 40189

View attachment 40190

 

[Noahsdad]

Stainless is fairly soft and quite easy to drill out with a hand held electric drill and a tap set easy to come by.
I recently had 3 bolts shear on my windlass case (SS into aluminium alloy) and was surprised how easy it was to drill them out and tap new (next size up) thread.
If you can get behind the sheared bolt it my be easier to drill from there after a nice whack with a dot punch.
Alternatively there are stud removing tools which may work in conjunction with a bit of heat.
And helicoiling is not difficult either.
A bit of Tef-gel on the threads will make extraction less painful next time!
Good luck!

 

[jerrytug]

Assuming you can carry the ram,it looks like it's on your drive so yes..
Carry it to your local welding shop and get him to TIG a handle on the broken stub. Cost £5.00.
Step away from the mole wrench!

 

[Pladdatoo]

Assuming you can carry the ram,it looks like it's on your drive so yes..
Carry it to your local welding shop and get him to TIG a handle on the broken stub. Cost £5.00.
Step away from the mole wrench!

Fixed to the gates, so no I can't carry it underarm to the welders unfortunately.
Yes mole wrench safely placed out of reach

Helicoiling- time for a Google search on whatever that is!

I'm interested to learn that stainless is fairly soft and easy to drill - that is encouraging to know.

Stud removal tools - will google those also.

Thanks for your thoughts

 

[Lakesailor]

Can you not drill the remains out and replace with a bolt and nut right through the jaws, possibly enlarging the hole so a plain shank bolt can pass through?

 

[theoldsalt]

I think this is the first time I have heard/read anyone suggesting that Stainless Steel is soft and easy to drill. It certainly does not have that reputation.

 

[Pladdatoo]

Can you not drill the remains out and replace with a bolt and nut right through the jaws, possibly enlarging the hole so a plain shank bolt can pass through?

Yes, that is what I am now considering doing. My initial reluctance/uncertainty was a belief that stainless was not "fairly soft ans easy to drill".

In the interim, I have been googling away, and was getting hopeful that an extractor might work - but knowing how flipping tight the bolt is in there I'm not so sure. The use of some penetrating oiol sounds essential. - Is that just 3 in 1 or something else?

 

[Lakesailor]

Plus Gas. 3 in 1 is just light lubricating oil. You could use paraffin or diesel. But I think if both components are stainless they can become bonded and you are knackered. There is a term for it. Galling , I think.

 

[MM5AHO]

Drill a hole in it and use an "eazi-out". (like a reverse coarse threaded thread tap)

 

[philwebb]

Stainless is not normally easy to drill. If you do manage to drill the stud fairly centrally to use a stud extractor, after trying penetrating oil
(WD40 etc) try heating the part (blow torch) before you use force on the extractor. Heat often helps loosen seized parts by expansion.
Best of luck, Phil

 

[KellysEye]

Drill a hole with a Cobalt drill bit (stainless isn't soft) to the size of one of these that has a slightly smaller diameter than the bolt.

http://www.ebay.com/bhp/broken-bolt-remover - scroll down to V5Pc Screw Extractor Easy Out drill and guide set Broken Screws Bolts Remover

It screws in the opposite way of the bolt cutting a thread so you can unscrew the bolt easily. I've done that a few times and it works well.

 

[MrB]

I think this is the first time I have heard/read anyone suggesting that Stainless Steel is soft and easy to drill. It certainly does not have that reputation.

+1 :ambivalence:

 

[Hoolie]

I think this is the first time I have heard/read anyone suggesting that Stainless Steel is soft and easy to drill. It certainly does not have that reputation.

If you use a slow high torque drill with a cobalt bit and lots of lubrication it is fairly easy to drill. Run the drill too fast and/or let it get hot, it work hardens and THEN you're in trouble ... ...

 

[nigelmercier]

Stainless is fairly soft and quite easy to drill out ...

Have you got your nonsense hat on?

 

[Scotty_Tradewind]

Reminds me a bit of this thread...

http://www.ybw.com/forums/showthrea...p-an-inaccessible-hole-in-10mm-s-s&highlight=

S.

 

[Noahsdad]

I can only speak from my personal experience!
The SS bolts I drilled out were easy!
There are various levels of hardness for SS, 1/4 hard, 1/2 hard,etc, so I guess I got lucky.
Sorry for any of you that have had trouble drilling it I am afraid I can't empathise!
For general info 316 stainless is austenitic and cannot be hardened by heat treatment, only by cold rolling.

 

[bignick]

I would disagree that stainless is easy to drill, even using new cobalt bits at a slow speed.

There looks to be a reasonable stub of the bolt left, so I would be inclined to cut a slot in the end of it with a hacksaw, then use a flat bladed screwdriver to turn it. Heat and then cold and plus gas (or wd40 if you cant get hold of plus gas) to penetrate and it should come out with a bit of persistence and time.

Nick

 

[PabloPicasso]

Yes, that is what I am now considering doing. My initial reluctance/uncertainty was a belief that stainless was not "fairly soft ans easy to drill".

In the interim, I have been googling away, and was getting hopeful that an extractor might work - but knowing how flipping tight the bolt is in there I'm not so sure. The use of some penetrating oiol sounds essential. - Is that just 3 in 1 or something else?

Pour on boiling water in copious amounts. This will remove any salt corrosion binding it all up and make removal much easier

 

[TQA]

Buy 3 titanium or cobalt drill bits of the size you need.

Find a high torque low speed drill. Ideally one with a big chuck that only exposes a small part of the drill bit.

Centre punch to start.

Plenty of pressure and keep the drill cutting at all costs.

If you get a hole in the stud you can try an easy out but if it was seized to the point that the head twisted off you are unlikely to have much success. Some heat is always worth trying though.

Best of luck.

 

[oldbilbo]

Buy 3 titanium or cobalt drill bits of the size you need.....Find a high torque low speed drill. Ideally one with a big chuck that only exposes a small part of the drill bit....Centre punch to start.....Plenty of pressure and keep the drill cutting at all costs.....If you get a hole in the stud you can try an easy out but if it was seized to the point that the head twisted off you are unlikely to have much success. Some heat is always worth trying though.

I appreciate that you expect to 'do the job in situ', however it will be more than helpful to secure the job/end of the ram firmly in some sort of vice-structure, for otherwise the drill-bit AND the job will wander and you will be unable to apply enough pressure for long enough, in exactly the right spot. That's the principle of the pillar drill....

I would use one of these 'Triton Jaws' thingys....

.... but a 'grunty' mains, not a 'weebly' cordless, hand-drill.

Once I had a small through-hole, I would increase the diameter of the drilled hole incrementally by using larger-diameter drill bits. Quite soon, there will only be shards of stud material left in there, and your latest and greatest cobalt drillbit will probably 'wheech' those remnants out. From the experience of the several competent 'pro' engineers I've consulted, brittle 'EasyOuts' and their like break off in service as often as they do the needful. That compounds the problem considerably, and is best avoided.

Once the 'ole is re-established, you are counseled to check the integrity of the internal threads, which may well be damaged. Then you will need to 'tap' them clean again to avoid a repetition of the original problem. Oh, and use some of the gunk mentioned above to ease future removal.