Thread: Drilling a hardened steel vice

My vise is slightly different, but the clamps I made for it would work with yours with a minor mod, instead of the pin just mill a step.

https://www.woodworkforums.com/f65/sc...9/#post1358128

Originally Posted by jack620

I bought a new vice to mount on my recently acquired Hercus milling attachment. I intend drilling 4 holes through the vice to allow 8mm socket head screws to pass through and into 2 long t-nuts. The holes will be stepped to allow the heads of the screws to sit below the surface of the vice's base.

Today I started marking out for the holes and discovered that the vice is made from VERY hard steel. My scriber barely scratches the surface. Likewise a file. There is the added complication of the rebates along the sides of the vice potentially causing a twist drill to be pushed off line (assuming a twist drill will even do the job).

Due to the narrow width of the two 'rails' of the base, the holes will be partially in these rebates (i.e. the screws will be exposed). That doesn't bother me as long as I can drill the holes straight.

Should I consider a solid carbide drill bit or maybe a slotting mill? Or will a cobalt twist drill will do the job? I want to get this right, so I'm not keen on just jumping in and stuffing up a good vice.

Chris

try sharpening a masonary drill like an end mill find a drill that will drill a hole in a ball bearing

Chris,

I've been thinking about this and being an exponent of doing the least when you can get away with it, here's a lazy way of mounting the vice along the lines of Michael G's drawing. No milling involved. A strip of flat bar threaded M6 or a 1/4" can replace the tee nuts in the Hercus slide table. I say this because it is all I ever used to secure my little home made vice to both the vertical milling attachment and the No.O mill table. I never shook the thing loose.

The photos should explain the rest. This mickey mouse setup should suffice until you can mill the clamps you require. The Waldown vice is a stand in. I don't have a grinding vice. The first photo show's the robust hold down clamp supplied with that vice.

BT

Originally Posted by Anorak Bob

A hand held 1 1/2 horse Makita. Instant destruction with the flick of a switch.

Yep, I have a Makita in my router table. And being a Makita, it has the horrendous noise that seems to afflict all power tools made by that manufacturer. That and crappy little switches and cords that are too short. Still are they are solidly built.

Thanks again for the replies. As I don't have any 3/16 x 5/8 bar I'll turn up some t-nuts are per Michael's suggestion. I think I'll use Bob's 2 piece clamping arrangement to hold the vice to the adaptor plate. Then I'll be in a position to make 'proper' hold-down clamps like Big Shed's and some t-bars.

Chris

One down, three to go.

Michael

Thought I'd better provide an update on my progress after all the input you guys gave me. I've got the vice mounted on the milling attachment using the adaptor plate method. It's currently held down by 4 temporary clamps. I'll make proper ones out of 25x25 MS if I ever receive the ER40 collet spanner I ordered on eBay nearly a month ago.

Because I can only hand tighten the collet nut I've been milling soft stuff like Delrin and aluminium. I can do MS if I take very light cuts.

The milling attachment is a great addition to the lathe.

Chris

Thought I was just about the only one who knew about drilling hardened steel with masonary bits, ha ha.

Anyway I'll just throw in how I was told to do it. It may not be the best but it has worked a lot for me. I didn't sharpen the bit and I used the fastest speed my drill press would do. I flooded the bit with coolant so the brazing would not melt, but the high rpm and the pressure causes the hardened steel to heat up and soften at the point of contact. Nothing happens for a few seconds then all of a sudden it starts drilling through.

Mitre 10 have some Bosch multi-purpose "masonary" bits in blue packs. Basically seem like a sharp masonary drill bit as a few have mentioned here. I've used these with success on hardened steel too.