benchtop vise restoration
Re: benchtop vise restoration
Also fit a spring , keeps preload on the screw.
Re: benchtop vise restoration
Hadn't thought of that.
A coil spring is going to get messed up getting crushed, but a belville spring (or even a split lockwasher with the sharp edges take off) will work to take out the slop.
Was thinking of adding springs to the locking screws so that when you unlock it, it pushes the bar down to free it up. I did the same with my tailstock and it makes it easier to slide. There isn't enough room around the screws to fit a spring, but I could put a flat spring in the middle of the bar and that would have the same effect.
Steve
Re: benchtop vise restoration
Looked up the sizes available on the locking collars and there is 1/2" which is slightly smaller than the shaft diameter of 0.556.
I figure if I can bore it out for part of the depth, I can create a shoulder that will fit into the groove so that it can't slip.
Steve
I figure if I can bore it out for part of the depth, I can create a shoulder that will fit into the groove so that it can't slip.
Steve
Re: benchtop vise restoration
The spring should go where it's only under compression when loosening the vise. It doesn't need to be much. Coupled with a couple washers to allow it to spin on the screw and keep it centered, it should be fine. You'll probably want the washers anyway to keep whatever spring is used centered on the screw since it has to be oversized to fit over it
Re: benchtop vise restoration
Yes, we are talking about the same thing.
If I don't use a spring, I may just use two of the locking collars with a spacer between to take up as much slop as possible.
Steve
If I don't use a spring, I may just use two of the locking collars with a spacer between to take up as much slop as possible.
Steve
Re: benchtop vise restoration
More vise work.
Decided that instead of counterboring the locking bar for bolt heads, just thread the bolts directly in.
Took some grade 8 bolts, turned the heads off, single pointed threads and finished them with a tap (die?).
Then drilled and tapped the locking bar. For tapping, I used a trick my dad taught me:
Drill the hole, and without moving anything, put the tap in the drill. Start the drill, bring the tap close to the hole, turn the drill off and when you think the speed is right, pull down on the lever and stick the tap in the hole. It will thread is a turn or two, but dead straight. Then I used a spring-loaded tap follower that fits in the back of the tap to guide it straight while tapping. Based on the spacing and the bolt diameter, the measurement outside the bolts should be 4.119". It came to 4.1175".
Not bad for marking with a caliper and using punch marks. Here's the old and new locking bars. Steve
Decided that instead of counterboring the locking bar for bolt heads, just thread the bolts directly in.
Took some grade 8 bolts, turned the heads off, single pointed threads and finished them with a tap (die?).
Then drilled and tapped the locking bar. For tapping, I used a trick my dad taught me:
Drill the hole, and without moving anything, put the tap in the drill. Start the drill, bring the tap close to the hole, turn the drill off and when you think the speed is right, pull down on the lever and stick the tap in the hole. It will thread is a turn or two, but dead straight. Then I used a spring-loaded tap follower that fits in the back of the tap to guide it straight while tapping. Based on the spacing and the bolt diameter, the measurement outside the bolts should be 4.119". It came to 4.1175".
Not bad for marking with a caliper and using punch marks. Here's the old and new locking bars. Steve
- liveaboard
- Posts: 1971
- Joined: Sun Dec 08, 2013 1:40 pm
- Location: southern Portugal
- Contact:
Re: benchtop vise restoration
If it's a through hole in mild steel, I just drive the tap right through with the drill.
One time I tapped 110 8mm holes through 6mm steel with a handheld power drill.
The tap made it through the end without breakage, but the drill was toast. And it wasn't a cheap one!
One time I tapped 110 8mm holes through 6mm steel with a handheld power drill.
The tap made it through the end without breakage, but the drill was toast. And it wasn't a cheap one!
Re: benchtop vise restoration
The slowest speed on my South Bend drill press is too fast for that, and probably doesn't provide enough torque.liveaboard wrote: ↑Thu Jul 23, 2020 12:38 pm If it's a through hole in mild steel, I just drive the tap right through with the drill.
One time I tapped 110 8mm holes through 6mm steel with a handheld power drill.
The tap made it through the end without breakage, but the drill was toast. And it wasn't a cheap one!
I have a slow-speed attachment (actually for a Delta), but I haven't installed it yet. That would give me an appropriate speed.
Also, using a spiral point tap so the chips evacuate in front of the tap is key to power tapping a thru hole.
Steve
- liveaboard
- Posts: 1971
- Joined: Sun Dec 08, 2013 1:40 pm
- Location: southern Portugal
- Contact:
Re: benchtop vise restoration
I have a vfd on my [ancient] drill press now; it's wonderful.
Re: benchtop vise restoration
I don't think that would have helped in this case, as the torque needed for tapping would not have been available.liveaboard wrote: ↑Fri Jul 24, 2020 5:28 pm I have a vfd on my [ancient] drill press now; it's wonderful.
I know how much torque it took to turn it by hand.
Steve
Re: benchtop vise restoration
BTW, here's the tool with a scale.
SteveRe: benchtop vise restoration
So here's what we came up with to keep the screw from unscrewing.
Got some 1/2" 2-piece claiming collars, the kind you can install on a shaft in place.
Put some think washers in them to add a little separation to ensure good clamping once they were machined.
Bored the holes out to the dimension of the shaft, leaving a ridge at the end to go into the groove, Found another bronze washer, bored it out. Got a piece of brass and bored it out to make a spacer to take up the rest of the space. Installed it all and it has enough play to not get jammed up and seems to run pretty smooth on the bronze washers.
Got some 1/2" 2-piece claiming collars, the kind you can install on a shaft in place.
Put some think washers in them to add a little separation to ensure good clamping once they were machined.
Bored the holes out to the dimension of the shaft, leaving a ridge at the end to go into the groove, Found another bronze washer, bored it out. Got a piece of brass and bored it out to make a spacer to take up the rest of the space. Installed it all and it has enough play to not get jammed up and seems to run pretty smooth on the bronze washers.