Unable to remove screw from table insert

[SpecialV4213]

I have a Mark VII and the front screw for the table insert is completely jammed. I’ve tried heating it up, and that didn’t work. The head is nearly stripped out and I’m out of ideas. Any help would be greatly appreciated! TIA.

[br549]

I have successfully drilled thru screws (including set screws) with stripped out heads before. Select a bit small enough to remove SOME or PART of the screw body, without risking damaging the threads in the table itself. You may not have to drill completely thru, but enough to be able to pry the remaining part of the body of the screw loose with a dental pick or something similar. The screw is going to be pretty hard metal, so pick a good, strong, sharp bit. You may need to run a tap thru the hole afterwards to clean it up. If you accidentally damage the threads in the table too much, then you may have to go up in size and tap a new hole.

[DLB]

Some additional thoughts and suggestions:
A 4 MM hex key is usually slightly larger than a 5/32" one and might give a better 'bite.' Try every hex key you own to find the best fit.
Use penetrating oil and let it soak.
Make sure the socket is clean and free of compacted sawdust so the key goes in all the way. Sometimes a pick tool and compressed air helps.
An impact tool might help free the threads. Also might strip the head the rest of the way so don't rush into this. There is a type of hand impact that is driven with a hammer and gives more control. I think Lowe's still carries these under the Craftsman brand. You'll need adapters to get it to 5/32" or 4 MM.
There are screw extractor tools that engage the head of a screw, unlike easy-outs that require drilling first. I've never tried these but would consider them in this case.
If you must drill, consider a left-hand drill bit.
It makes little difference but I'm curious, is this a 60's version Mark VII or a 21st century Mark 7? Good luck!

- David

[edma194]

If you are going to drill, and if these are through holes, start drilling from the bottom and you may twist the screw out as you go.

[SpecialV4213]

Thanks for all the advice. Sorry yes it’s a new Mark 7.

[Hobbyman2]

You can get screw extractors that look like drill bits however they work in a ccl rotation and the screw will usually come right out . https://www.homedepot.com/p/RYOBI-Spira ... /205469301

[DLB]

This is the extractor type I mentioned that engages only the head of the screw: https://www.homedepot.com/p/Ontel-Speed ... /207096720 Again, not an endorsement as I've never used them. But I'd try it for this.

I mentioned using a left hand drill if you must drill, and edma194 (Ed) mentioned drilling it from the bottom. But not both. Either idea is intended to put CCW (as seem from above) torque on the screw, potentially loosening it. They are through holes on the new style Mark 7. Some disassembly required.

Penetrating oil can also go in from the bottom with the table turned over, and will probably be more effective this way. I don't think you'll have to disassemble it.

- David

[RFGuy]

Full disclosure - I am not a machinist, but I am fairly mechanically inclined. In my brief experience of using extractors, I did NOT have good luck with the type similar to the Ontel brand (mentioned by David). However, I had a great experience with the style like the Ryobi ones (mentioned by Hobbyman2). I have both types now, but the Ryobi type would be the first ones I would grab the next time I need to extract a screw/bolt. Of course, each case is unique so maybe my stuck fasteners were too difficult for one versus the other. Also possible that I didn't use the correct technique with the Ontel type of extractors. Just my own experience...

[JPG]

Guess Everit is not watching. Heat a sacrificial allen wrench red hot an insert into the head socket. Leave it there so the heat will transfer to the screw.

After it cools try removing with a "new" allen wrench.

[SpecialV4213]

I do thank everyone for their valuable information. Tapping a 4mm hex head wrench into the screw worked like a champ.
Now I just need to replace the screw but the old one is still usable until I get it.