Bridgeport Clamping Recommendations

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Rick_B

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I need to get vise keys for a 6" Kurt vise and t-nuts to clamp it to the table. Any sugestions for a good source? Should I be considering a complete clamping lit as well?

Thanks
Rick
 
depending on the sort of projects you intend on doing. will you be clamping things to the table/fixtures/etc? if so, a clamping kit is in your cards, if not, you can probably get away with a couple of studs and nuts. you can make the t nuts on your mill (drill hole, then bolt to table with substrate, and mill the t-nuts to shape)
 
You could buy a complete hold down kit if you need one, and don't already have one. The T-slot keys will come with a hold down kit. The keys for the Kurt can be made up fairly easy. Other wise, you can just turn down some round stock to fit yor table slots, and drill to fit the bottom of your Kurt. I used to go through the trouble to machine the keys for all my different vises. But over the yrs, Ive found the round keys work just as well. The round keys have one added bonus too. You can rotate them to get the vise to near zero with out tapping the vise around. I just drop the vise on, push it forward, snug it down and its good to 0.002 or less.
 
You don't need the alignment keys, in fact some people will tell you never to use them because they can be off (or the table slots can be off). I would recommend a clamping kit, regardless. Buy two extra T-nuts, 2 extra nuts, and 2 extra studs to hold the vice in.

Not sure if there is a brand of clamping kit that comes with keys, but mine did not (it is a Gibraltar IIRC). My vice came with the keys installed.
 
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At work we have nine 6" Kurt vises and one 8". None have alignment keys in them. If you want to have alignment keys, just make them yourself.

As far as clamping kits, if you come across one with a rack, it does help keep things organized.
 
Let me ask one more question to demonstrate my inexperience :) - the bridgeport t-slot is 5/8 and the kurt vise clamping hole is also 5/8. The recommended t-nuts/clamping kits use a 1/2 stud. Does this present a problem with vise stability with an 1/8 slop between the vise clamping hole and the t-slot?

Rick
 
Rick_B said:
Let me ask one more question to demonstrate my inexperience :) - the bridgeport t-slot is 5/8 and the kurt vise clamping hole is also 5/8. The recommended t-nuts/clamping kits use a 1/2 stud. Does this present a problem with vise stability with an 1/8 slop between the vise clamping hole and the t-slot?

Rick
Click to expand...

No, that allows you to perfectly line it up. Just use a washer so the nut doesn't move the vise when you tighten it.
 
thanks Jeff - BTW - I'm going to re-trm the head basd on your suggestion for tightening up the vsrous locks.

Rick
 
When it comes to clamping a Kurt vise to the table using the keyways and keys, you may want to make your own keys. Kurt's are made with tight tolerances. But there is a difference in mill table slots. What fits one mill snug, may fit another mill with a little slop. Before I retired, I ran a Bridgeport, an Alliant, and also a Trak QuickCell 3 axis mill. One vise, with keys, fit each mill differently. I would have figured that the Kurt keys would have fit a Bridgeport rather snug, seeing that the Bridgeport is one of the most or more popular mills. It actually had a small amount of slop on the Bridgeport. Maybe .002-.004 in movement across the stationary jaw checking it with an indicator. Using the same vise and keys together, it had a very decent fit on an Alliant mill and had .0005 movement across the 6" jaw checked with the indicator. On the Trak QuickCell, I had to remove the keys because they were size for size or let me rephrase that......I checked the table slots with a .625 gage pin that are .0002 undersize, and the gage pin was snug.

So for the money, I would check the mill that you are going to put it on as to the size of the table slots, then make your own keys out of 0-1 Tool steel and harden them. Once you get a dedicated set made, make sure they stay with that mill and vise unless you plan on moving that vise to another mill. If you do that, and the keys appear to fit, drop the vise on the table and bolt it down. Check the vise out to see if it is tight. If it has any slop, or is too tight, then make a dedicated set of keys to stay with that mill and table.
 
Rick_B said:
Let me ask one more question to demonstrate my inexperience :) - the bridgeport t-slot is 5/8 and the kurt vise clamping hole is also 5/8. The recommended t-nuts/clamping kits use a 1/2 stud. Does this present a problem with vise stability with an 1/8 slop between the vise clamping hole and the t-slot?

Rick
Click to expand...

I use 5/8 T bolts, thick flat washers and washered nuts, all from Gibralter. There is still PLENTY of room to adjust my Kurt 6 inch vise on my Bridgeport. I never liked the idea of a tiny bolt in a large hole or slot. There's a reason why the slot is 5/8 wide, plus clearance.
 
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