Vise locating blocks

[redvan22]

Hi everyone.
I have a vise that is modeled off a Kurt vise and it came with two small blocks that mount in a groove under the base with two screws. There's actually two grooves that form a cross. I do not fully understand the purpose of these blocks and the grooves other than they seem to offer some alignment aspect of the vise to the bed but there's still plenty of play. I thought perhaps their purpose was to align the vise without the need for dialing in the vise but since there's play, that doesn't make sense.

What is their true purpose?
Michael

 

[mattthemuppet2]

That's the idea. Plop the vise on the mill, push those blocks against one edge of the t slot (unless they're a tight fit) and the vise should be trammed in. Saves time compared to using an indicator

 

[Eddyde]

Yep that's what there're for, easy alignment. Kurt sells "Step Fixture Keys" of various widths to accommodate different table slot sizes. The size of the slot on the bottom is 11/16" (0.6875") for the 6" vises (I think the larger vises have a different slot size). If your vise has the same slot size you can probably use the Kurt Step Keys, or you can easily make your own. I use them and find my vise repeatedly registers within .001", accurate enough for most of the work I do. If I want .0001" then I tram it with an indicator.

 

[RJSakowski]

On my Tormach mill, the front edge is the reference surface. I pull the vise tight to that surface to align. Actually, I use a piece of 2x4 against the column to hold the vise tight to that edge while clamping it down to prevent the vise from shifting.

 

[epanzella]

I don't use the blocks that came with my 6 inch vice. The vice is so heavy I can barely get in place on the mill let alone place it with the blocks perfectly aligned. I'm afraid the blocks will groove the table. It only takes a cupla minutes to dial in the vice.

 

[Eddyde]

I don't use the blocks that came with my 6 inch vice. The vice is so heavy I can barely get in place on the mill let alone place it with the blocks perfectly aligned. I'm afraid the blocks will groove the table. It only takes a cupla minutes to dial in the vice.

I set the vise down on a piece of plywood, align the blocks to the slot and then slide the vise off the wood onto the table.

 

[G-ManBart]

Just know that if you're using the blocks it's probably only going to be close, not necessarily perfect. For most stuff it probably won't matter, but if you're going to do something precise, it's time to break out the indicator and check.

 

[Larry$]

I set the vise down on a piece of plywood,

I do the same except with 1/4" Masonite. I machined the blocks with a slight taper so they easily drop in to the slot but go snug when at full depth. Vice lands close enough for what I do. There is no noticeable play. I've done the same for my 8" rotary table and for my indexing head & their foot stocks. Makes for much faster setups. I store them on wood bases with a sloppy groove for the blocks. I'd like to claim to be a tenths machinist but it ain't true. My DRO shows ,0002 but will flicker off that pretty easily. I'm lazy so I use the DRO for almost all positioning.

 

[Illinoyance]

My vise is keyed to the table. Tram of the fixed jaw is balls on. If I need to tram the head, I can slide the vise to one end of the table and tram directly to the table. When I slide the vise back into position, the tram of the jaw remains true. I am a big fan of fixture keys.

 

[keeena]

If you use keys: you might also want to make simple base with a groove in it to store the vise. That way you can store on a shelf w/o tearing up the shelf or keys.