Removing Slot Gib Screws

Spent a couple of hours with my almost civil war patented horizontal mill yesterday. Somebody has to take it apart, just seems like it is always me that has to do this kind of stuff. The gib screws are .6" X

2" with single slots that are wallowed to the point of looking like snow angle's wings. I got 4 out of 10 out and pounded on them with a 3/16" flat round ended punch counter clock wise.

When I started typing I thought of welding a tire iron slotted end... don't have 6 of them. I really don't want to have welding marks on the machine cause I can never see well enough. Nuts may work, but will be worried that I'll weld the screws to the machine, the way I weld !

I use to have to get allen screws out of crankshafts and am pretty good with drills and easy outs. Never did fail on a crank. But, having trouble foreseeing a drill bit against a slot wallowed bigger on each side than the middle. Couldn't remember if HHS shatters like carbide, that didn't take long. The fast and dirty chisel cut a couple of times till it shattered.

Got some funny dressed drill bit/mill bits from Mr. GD that I'm not sure what they are for. 90 degree step so I guess putting counter sinks with. Couldn't find them just a second ago, but know they are there. Maybe those and then to a real HHS american made step drill? The step bit won't do it alone. Or maybe dressing a chosen drill bit to looking like a large pencil point? I don't own any small metal chisels and don't want to destroy a punch, but that might work, to chisel the remaining sides to drill without total chaos.

I read all the recent posst about auto stuck studs, what else is missing. I can borrow a die grinder, but don't have a sharp bit.

SW

Reply to
Sunworshipper
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Kinda sounds like a job for one of the manual hammer type impact drivers. Soak the problem screws in with Kroil for a few days and then a good whack with the impact driver will probably get them out since they are likely not stuck too bad if you got the others out.

Reply to
Pete C.

I'm not exactly sure how it's set up, but maybe you could pull the knee or saddle off so you can remove the gibs and get access to the backside of the screws that you're trying to remove. If they're near the surface of the dovetail, you might be able to grind a slot with a dremel and screw it out that way. Just a thought.

Reply to
Denis G.

Anyone who has used one of these back when motorcycle case screws were soft *phillips head* can attest to the magic of which those hammer- driven impact drivers are capable.

Dave

Reply to
Dave__67

Are you using left-handed bits? That way if it drills, fine. If the bit grabs and tries to turn the screw, fine. The drill pulls the screw out more often than you might think. If you're worried about staying centered, maybe make a block with an appropriate sized hole to help guide the bit? --Glenn Lyford

Reply to
Glenn Lyford

Never had or tried left-landed.

You know that had crossed my mind, but when I read it, it occurred to me that I could bolt a guide onto the top of the platen/table and have it 90 degrees downward, drill through, and that all the screws should be at the exact same plane.

That's a great idea, thanks. Best start looking for some metal that is 90 degrees on the inside.

SW

Reply to
Sunworshipper

I was going to suggest left hand drills also. They are my GOTO solution for nearly all stuck fasteners. In this case, you'll have to make up some sort of drill bushing/guide to get as near center as possible.

Karl

Reply to
Karl Townsend

Well, that seemed like it would work. Found a large angle iron and drilled and taped a couple of holes and clamped on a piece of aluminum with a hole for a guide and then clamped the angle iron down on the platen. First bit was toast. Then found the smallest chisel and went for it to make wallowed slot closer to the profile of the end of the bit, and this stuff breaks more than cuts, second bit, toast. Now a

1/4" bit can be used readily, and it is toast. Looks like welding is the next option. I wouldn't think they would make these so hard.

I think I'll just make up new ones with square heads.

Oh, looks like the slots in the platen are different from everything else that I have. Guess they never made anything standard.

SW

Reply to
Sunworshipper

That's what did it, got them all out. My dad must have had one years ago, cause I knew what you where talking about. The uncle-in-law has one. Wasn't easy though. Now back to the fun part. But, I think it's missing the main wheel I bet. Found a cool Brown & Sharpe patent list and the one I'm looking for isn't there. Now I need to figure out this trip pin for end of travel reverse switch that is in the way of the control box cover.

Thanks

SW

Reply to
Sunworshipper

Good to hear it worked. I've got one of those impact drivers here somewhere too. I've also got a modern Makita cordless impact driver that works wonders on many things, though it doesn't provide the forward force that the hammer impact drivers do to help keep the bit from slipping.

Reply to
Pete C.

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