Veritas Twin-Screw Installation Question

[Ben Beckham]

Question: How tall can the jaws be on the Veritas TS vise be? Is there a point where it's too tall?

Backup:

The first and only bench I've ever had just had to go. I was a sheet of 3/4" OSB screwed to a frame of 2x4s with a machinist/mechanic iron vise on top of it. It was totally falling apart. Looking back, I almost get a bit nostalgic thinking about all the furniture that I've somehow managed to construct with it.

Almost. So I demolished it.

Then I ran into the old problem of needing a bench on which to build a bench. So I decided to build something cheap and good enough for now. The legs are 3 layers of 2x6 SYP, the stretchers are 2x6s sandwiched through the layers in a sort-of-MT joint, and the top is 6 layers of 2' wide by 7' long MDF. There's a whole gallon of glue and a lot of nails hidden in there. It won't win any beauty contests (not by a looooong shot) but its ridiculously heavy with a flat top that is flush to the legs.

So my bench top is 4.5" thick, and after reading the instructions for installing the TS, it looks like I'll have 5.5" of jaw above the screws. I'm concerned about top to bottom racking. Will it be fine this way or should I look at hogging out an inch of the underside with the router first?

Thanks!

[Greg Portland]

OK, so if I'm understanding your description you are incapable of installing the TS -in- the bench (due to metal inclusions, etc.) and HAVE to under-mount the vise. I can tell you that I have 4" of jaw height above my TS vise screws and have not experienced any racking (2" maple faces). Call Lee Valley, they will give you their official recommendations for jaw height (it will vary based on face thickness and material). If it's less than 5.5" then yes, you'll need to hog out the underside. However, you've already said that there are nails in there (which you will hit with your router bit).

[Ben Beckham]

Most of the nails are in the legs. I didn't put that many nails in the top and I purposely avoided areas I knew I would be installing a vise in later, so I'm not worried about that. The installation instructions seem to indicate that an under-mount would be typical. I'm not even sure how I would go about boring the holes for the vise screws installed IN the bench anyway. I don't think I've ever seen that done, but then I haven't really been looking.

[Greg Portland]

I ran holes through my bench but I planned my entire bench design around the vise. It was a 5" thick torsion box design. Doing it after the fact is probably going to be a mess. Anyway, ping LV, they will tell you exactly what the limits are for face height.