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Drilling hardened vice
- Thread starter Cobra
- Start date
It won't be easy. Of course it would be easy if you had access to a plunge EDM machine. But if you had to pay to have it done, it would exceed the value of the vice.
If you wanted to try and drill it, it could be done with a carbide tipped drill. I'm occasionally required to drill hardened (58-60 RC) die plates up to 1" thick. I will detail how I do it. 1)The more ridged and true running the drill press the better. 2)Slower is better.
for a 1/4 inch hole I would use a low RPM, around 100, and no coolant or lubricant. Instead use continuous compressed air and keep it focused right on the hole you're drilling. it doesn't need to be a huge blast, just enough to keep the drill from getting too hot, and to keep the hole clear of the small chips you will be making. use steady, but not too much pressure, just enough to get the drill to cut. Keeping the drill cool is important, because once inside the hole it will get hot, and expand, and the carbide will shatter. I know from experience. The tip of the drill will get dull, and it will need to be touched up a little every so often. You'll know when because it will stop cutting, and you'll have to keep applying more pressure to get it to cut. The drill doesn't have to be perfect, but the cutting edges need to be "edges" Be patient, it might take 20 minutes or more to drill each hole.
Another idea would be maybe you could grind slots in from the sides where you want the screws to go. it wouldn't be as pretty, but it would be a low tech way to get the job done.
If you wanted to try and drill it, it could be done with a carbide tipped drill. I'm occasionally required to drill hardened (58-60 RC) die plates up to 1" thick. I will detail how I do it. 1)The more ridged and true running the drill press the better. 2)Slower is better.
for a 1/4 inch hole I would use a low RPM, around 100, and no coolant or lubricant. Instead use continuous compressed air and keep it focused right on the hole you're drilling. it doesn't need to be a huge blast, just enough to keep the drill from getting too hot, and to keep the hole clear of the small chips you will be making. use steady, but not too much pressure, just enough to get the drill to cut. Keeping the drill cool is important, because once inside the hole it will get hot, and expand, and the carbide will shatter. I know from experience. The tip of the drill will get dull, and it will need to be touched up a little every so often. You'll know when because it will stop cutting, and you'll have to keep applying more pressure to get it to cut. The drill doesn't have to be perfect, but the cutting edges need to be "edges" Be patient, it might take 20 minutes or more to drill each hole.
Another idea would be maybe you could grind slots in from the sides where you want the screws to go. it wouldn't be as pretty, but it would be a low tech way to get the job done.
try a carbide tipped masonry bit, run about 1000-1500 rpm and cool with compressed air.. carbide is made to run fast, not at 150 rpm..
I have never ran a carbide drill bit under 1000rpm, I run alot of 1/2" carbide endmills in heat treated h-13 and viscount and run 1500-2000rpm all day long.
A good center cutting carbide endmill would probably work fine, feed isnt as critical with carbide, just keep the hole blown out and keep compressed air on it constantly...
A carbide spotdrill might work, depending how thick your going through..
I bet once you get into the sine vise you'll find its not that hard, I've seen import vises that were just case hardened, pretty soft after you got through initial .060. or so.
I have never ran a carbide drill bit under 1000rpm, I run alot of 1/2" carbide endmills in heat treated h-13 and viscount and run 1500-2000rpm all day long.
A good center cutting carbide endmill would probably work fine, feed isnt as critical with carbide, just keep the hole blown out and keep compressed air on it constantly...
A carbide spotdrill might work, depending how thick your going through..
I bet once you get into the sine vise you'll find its not that hard, I've seen import vises that were just case hardened, pretty soft after you got through initial .060. or so.
You might try spot annealing the vise using either a oxy-acetylene torch with a fine tip, or a solid copper rod in a stick welder, I've used both tricks to spot anneal 1903A3 receivers that were very hard, so that they could be drilled and tapped for scope mounts.
Solid Carbide Die drills are also extremely hard and will generally cut through hardened steel quite easily. As noted above, they need to be run at high speed, plenty of coolant or compressed air stream to get rid of the chips and excess heat.
Solid Carbide Die drills are also extremely hard and will generally cut through hardened steel quite easily. As noted above, they need to be run at high speed, plenty of coolant or compressed air stream to get rid of the chips and excess heat.
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