Mounting the veritas twin-screw as an end vise

[Zach England]

I am ALMOST ready to start on my new bench. I finally got my veritas twin screw in the mail. I am waiting for my wooden screw and shopping around for a good price on ash lumber.

I am using the Veritas as an end-vise. My bench top will be 24 inches wide and I am planning on making it three inches thick with no skirt. I want to space the screws 18 inches apart, which does not leave much room on the ends.

My question is:

How should I join the jaws for the twin-screw to the bench top? In many of the pictures I see of large full-width end vises the just bolt onto the bench end and hang below the bench top by quite a bit. I don't see this as an acceptable method--it is just too crude and leaves the bottom of the jaw unsupported. I want to avoid using mechanical fasteners in this bench.

I figure my jaws will probably be 5-6 inches wide, so I am considering two basic ideas.

The first is to put a full-length tenon (tongue?) or a sliding DT in the end-grain of the bench top to join the jaw and putting some "cleat" type things below it to support the bottom half of the jaw and anchor it to the bench top.

The other thing I am considering is placing the legs of the bench at the very end and using some dowels or other joinery to attach the bottom half of the jaw to the legs and using another method (like sliding DT) to attach the top of the jaw.

Thoughts? Do these ideas make sense or do I need to make illustrations?

I'd love to hear from people who have mounted a wide vise on the end of a bench.

Thanks, as always.

[Mark Ketelsen]

Here are photos of my bench build from a few years ago. They show how I mounted the twin screw as face wise.

http://s287.photobucket.com/albums/ll125/mketelsen/Holtzapffel%20Workbench/

[Bart Nadeau]

The end is where it's intended to go. You can download complete installation instructions for the Veritas TS vise from the LV site.

[Zach England]

I have those instructions. My question has more to do with the construction of the bench. Maybe I am over-thinking it.

[Mike Allen1010]

Zack, the challenge you have here is a function of accommodating long grain versus cross grain wood expansion when using the veritas twin screw in a tail vice position.

Most tail vices are intended to be be bolted to the underside of the benchtop and have slots in the vice attachment points that allow the bolts to move within those slots as the benchtop expands/contracts. In contrast, the veritas twin screw can't be bolted directly to the bottom of the benchtop. It has through fittings for the threaded vice screws that can only be mounted to a skirt, end cap or vice chop that extends below the bottom surface of the benchtop.

The concept you mentioned of Incorporating some kind of end cap attached to the benchtop via sliding dovetail/breadboard tenon is probably the way to go as attaching the vice rod fittings through this piece will ensure the distance between the vice screws won't change over time as this dimension is independent of any expansion/contraction of the benchtop.

You will probably have to route some channels in the bottom of your benchtop to house threaded rods that will allow you to bolt the end cap to the benchtop. If you make these slightly oversize it will allow the end cap to move with the expansion/contraction of the benchtop, without changing the spacing between the vice screws.

This sounds kind of complicated but if you look through the T.S. vice parts it should make more sense.

Mike

[Greg Portland]

How should I join the jaws for the twin-screw to the bench top?
Zach, I've got one on my bench and used 8/4 maple for the jaw faces. One of the faces will be the end cap on your bench and the threaded rod goes through this face. On the backside, you'll have large mounting nuts that get screwed into the wood. With a 2-3" solid top you can undermount the screws. With a thicker top you'll need to route or drill holes for the rod through the bench + allow room for the mounting nuts such that they still have wood to screw into. Plan on adding some wood scraps between the screws and table bottom if sag bothers you.

The table-side jaw will want to get pulled off the table when you're using bench dogs & not just the vise faces. I would recommend using a sliding dovetail or dovetail the end to the front and rear bench aprons. On my bench I used mechanical fasteners (top was a torsion box & not solid wood).

I would strongly recommend cutting some pieces of MDF or cheap wood and do a mock up with the vise hardware. LV is not joking when they tell you to -really- read the directions (a few times!).

[Zach England]

Zach, I've got one on my bench and used 8/4 maple for the jaw faces. One of the faces will be the end cap on your bench and the threaded rod goes through this face. On the backside, you'll have large mounting nuts that get screwed into the wood. With a 2-3" solid top you can undermount the screws. With a thicker top you'll need to route or drill holes for the rod through the bench + allow room for the mounting nuts such that they still have wood to screw into. Plan on adding some wood scraps between the screws and table bottom if sag bothers you.

The table-side jaw will want to get pulled off the table when you're using bench dogs & not just the vise faces. I would recommend using a sliding dovetail or dovetail the end to the front and rear bench aprons. On my bench I used mechanical fasteners (top was a torsion box & not solid wood).

I would strongly recommend cutting some pieces of MDF or cheap wood and do a mock up with the vise hardware. LV is not joking when they tell you to -really- read the directions (a few times!).

OK, thanks. I think I will dovetail the ends. I don't know if I can pull off the big of a sliding dovetail.

[Jim Neeley]

+1 on really reading. Sine the rear nut mounts into the rear jaw, if you have any question on your ability to do it *precisely* as described or want to mitigate the probability of problems, I'd suggest assembling the vise in it's entirety prior to mounting the rear jaw to the bench, then unscrewing the front jaw and rod, mount the rear jaw and re-start the thread. The LV twin-screw design requires much tighter construction tolerances than the L-N to perform correctly due to the LV nut nounting to the rear jaw and the L-N mounting to the underside of the table.

...or so I found when installing the LV as an end vise and the L-N as a face vice, both 24"OC, on my bench.

[Gary Muto]

+1 on really reading. Sine the rear nut mounts into the rear jaw, if you have any question on your ability to do it *precisely* as described or want to mitigate the probability of problems, I'd suggest assembling the vise in it's entirety prior to mounting the rear jaw to the bench, then unscrewing the front jaw and rod, mount the rear jaw and re-start the thread. The LV twin-screw design requires much tighter construction tolerances than the L-N to perform correctly due to the LV nut nounting to the rear jaw and the L-N mounting to the underside of the table.

...or so I found when installing the LV as an end vise and the L-N as a face vice, both 24"OC, on my bench.

Jim,
I'm planning to mount 2 twin screw vises (24" OC as well). I understand the installation of both vises from reading the manuals. I see LN aslo offers a jig that can be borrowed. Either design looks do-able. The LN outside chop is a little complex, or expensive if you buy it. If you were to buy one brand, which would it be?

I got the LV vises. I like that they can be adjusted to rack as needed and the price is really good for waht you get. The only downside I see is the potential to sag and that can mostly be addressed with rob strips between the bottom of the bench top and the top of the screws. I suppose that you could also mount another set of nuts but that would reduce the maximum opening.

I have to make 4 chairs for a kid's table before I can start my bench so the vises are not yet installed.