Can I put a front vise on this workbench?

[BAlex]

Hi,

I just built a workbench. The table top is 3/4" MDF on top of 3/4" plywood on top of a frame of 2x4 pine studs. My question is, can I reasonably put a front vise on this?

I'm worried that screwing the vise into plywood and MDF won't hold. I'm also worried that the pine 2x4 isn't a good back jaw. I suppose I could add a back jaw of maple or oak, but then the back jaw won't be flush with the edge of the worktop. Is that a problem?

This is not an uncommon workbench design. How do people put a front vise on it?

Thank you,
   Bob

[Admiral]

You are right to be worried, not much of a foundation. I'd expand the 2x4 frame in the mounting area, and use carriage bolts to secure the vice through the top. Not optimal, as bolt heads will show, but that's all I got. You could layer another piece of ply on the top to hide the bolts.

[ez-duzit]

You must be referring to a woodworking vise. You can countersink the top for flathead machine screws or counterbore for cap screws. If the fixed jaw requires lags into the bench make certain there is a piece of hardwood let into and epoxied to the bench to hold the threads.

[Mike in kc]

I built my benches as my third and fourth projects about 20 years ago using solid core fire doors, edged with Oak and mounted the vise using carriage bolts recessed into the top of the bench.   

As you can see, it's been well used.

[robert146]

Mount with through bolts. Don't even consider screws!

Rear jaw needs to be flush with edge of bench. I would just add a front edge to make it even with the rear jaw after I had the vise mounted and the false jaw installed. I would not alter the original bench (since it was someone else's plan), and may,or may not, have been designed for a vise.

The pictures in Mike's post are pretty representative of the vise will be used for.

R.

[fredhargis]

Yep, counterbore for hex (or carriage) bolts. Then fill the holes with whatever you want.

[lincmercguy]

As others have said, use through-bolts.  My bench has two layers of 23/32" ply with a layer of hardboard on top.  I just have a 7" vise and am not terribly hard on it.  I used some soft maple to space it down to make the top of the jaws slightly slower than the top.  I then used soft maple as jaw faces flush with the top of the bench.  So far, so good.  I wanted to find some reclaimed bowling lane for the top originally, but everyone wants to use it for countertops, so it's expensive.

[handi]

You can certainly build up the underside of the bench to make it flush with the top.

Will your bench be an heirloom that gets passed through generations? No. But it will function for you for now. If you continue woodworking, and build a better bench someday, then the vise can be moved and will give even better service.

Do the best you can now, with what you have now, and grow as your skills do. If you wait until you have everything perfect, NOTHING will get done.