Benched dog/vice question

[Mike Allen1010]

I'm in the planning stages for new workbench and have a couple questions I'm hoping the forum can help me with.

I'm planning on a Ruebo style bench with a 4" thick benchtop. I prefer two rows of benched dog holes, on both long edges of the bench so I can use the tail vice to "4 point clamp" wide panels flat to the benchtop and plane them diagonally when needed.

Just finished Chris Schwarz book on workbenches and he recommends round bench dogs. My question is how do you get the round dogs to stay at the appropriate height? Is it just a tight friction fit between the dog and the dog hole (seems like over time as the dog/dog hole wears this friction would be lost?), or it's some kind of "spring" mechanism that provides the necessary friction?

My other related question is could I use a quick release large metal bench vise (Jorgensen, record?), As the tail vice? I'm wondering if the guide rods are far enough apart to prevent racking when I'm only using a single row of bench dogs?

I like the idea of the quick release to be able to rapidly adjust for different size workpieces without having to thread the vice screw in an out, but don't know if racking will be a problem. I don't really use a lot of pressure in this situation, just enough to hold the stock solid.

I'm planning a twin screw face vice. I currently have the Veritas twin screw which works well, however the dual handles get in the way occasionally. I'm leaning towards the Lie Nielsen twin screw, chain drive for a face vice. Does anyone have any experience or knowledge about that device?

Thanks, Mike

[Simon Frez-Albrecht]

You can use round dogs with a spring in them, like these:
http://www.leevalley.com/US/wood/pag...637,41645&ap=1

[Dale Cruea]

When using a single row of dogs on my bench I will put something in the side opposite side of the vice to stop racking.

[Joel Goodman]

+1 on the need to put an appropriately sized piece of wood in the vice (opposite side to the dog in use) to prevent racking. The guide rods in my vice don't do that -- they just keep the vice chop (if that's the right word) running fairly smoothly when its not under load. I have often thought that a recessed threaded screw with a wooden pad (sort of like the screw of a c clamp) in the moveable part of the vice (to one side) would be a good addition to prevent racking, both with dogs and in general use where only one side of the vice is grabbing the wood. I assume that the twin screw vices are designed to avoid the racking issue as one screw is more or less in line with the dog (or the work).

[Federico Mena Quintero]

About the dogs - check out this design: http://www.galoototron.com/2010/07/0...le-bench-dogs/

I think they are pretty cool.

[Jake Rothermel]

If you had a lathe you could take something like an 1" or bigger hardwood dowel and turn a portion of it down to 3/4". Then the dog just sits in your dogholes but rests on your benchtop. Flatten on face with a block plane for stronger registration of your work against the dog. This has always seemed like a brilliantly simple idea to me, though I don't have access to a lathe myself.

[Jim McGee]

I think Chris Schwarz had a blog a while back about using ball catches to hold round bench dogs in place. He drilled the appropriate sized hole in the side of the bench dog and inserted the ball catch.

[Jim Koepke]

I have drilled a 3/4" hole in small pieces of scrap and glued them to a 3/4" dowel to make dogs. One or more sides of the scrap can be planed at an angle to help hold the wood.

I tend to avoid even light holding in a vise for pieces being planed to avoid any bowing caused by the vise.

I find it is better to have dogs holding the piece at one end and along the side opposite from the direction of where it is being worked.

Holding pieces without distorting them is part of the challenge of woodworking.

jtk

[Jessica Pierce-LaRose]

How much of an issue is racking when using a vise with bench dogs? Glen Huey's "Shaker Bench" (originally from PW, I believe, and seen in chapter 7 of "The Workbench Design Book" [The red covered workbench book by Schwarz]) actually has the bench dogs in the wooden chop outside of the iron vise casting itself, and I've seen it in pictures holding stock with just one bench dog. (Like the picture on page 114 of the aforementinoned workbench book) Sure, the vise will rack, but since it's holding the work between just two points, particularly if you're using round bench dogs, won't it still hold the work fine? I have little experience with this, as I'm still constructing my bench, but my limited experience seems like it's not the huge issue that racking when holding stock on one side of the vise for say, cutting a tenon is

[Jim Koepke]

How much of an issue is racking when using a vise with bench dogs?

This depends on the user. For my use, it isn't an issue. There are piles of scrap close at hand to insert into the unused end of the vise chop to counter any racking.

If the vise is allowed to rack, the work piece may be able to slip out of the vise's hold.

jtk

[Joel Goodman]

How much of an issue is racking when using a vise with bench dogs?

I would be afraid not to put scrap in the vice to prevent racking --- I think it could damage the vice.

[Jim Matthews]

These are excellent.

I recommend waxing dogs like these, my "Dowel dogs" are forever getting jammed.
With no access from underneath my bench - removal eats into my shop time.

I use the Veritas bench top clamping gizmos - they all fit in the same 3/4" sized hole.
If you have an unusual piece to hold and can't reach - drill, Baby DRILL!

The only thing I would really add to the discussion of bench building is to leave sufficient overhang all the way around, for clamping.