Gary Blum's workbench design at IWF

[Mr__Bill]

An on line Popular Woodworking article describes his Baltic Birch ply workbench. I am wondering if any one here has seen it in person and....

How or what holds the pipe clamps in the bench? If it is the standard movable tail of the clamp how far in is it and is there a hand hold to reach it?

What are the brass bushings for?

I assume it's a torsion box but, is that top layer of ply replaceable?

And, of coures, your thoughts on the bench.

The flexibility of the vices makes the bench very interesting to me and I can't help but wonder if there are any holes through the bench top sized for the pipe clamp to clamp something down to the bench?

Bill

[annunaki]

Two Bits of information-

1. http://www.wikihow.com/Build-a-Torsi...-Workbench-Top

2. October 1996 Woodwork Magazine
"Workbench in a Weekend".

- Tom Casper presents plans for a torsion box workbench made of 2x4
construction lumber and plywood (I know, but its inexpensive). The
design includes an interesting tail vise made with a handscrew clamp.
Total cost less a front vise (subject of another thread) around $150.
Later in the magazine, in an article about the 4th street guild in
Minneapolis it notes that Mr. Casper is writing a book called _The
Unplugged Workshop_.

[annunaki]

Build your own TBWB

http://www.diynetwork.com/diy/cda/episode_print/0,1983,DIY_14350_26946_EPISODE-DETAIL-PRINT-NEW,00.html

[Mr__Bill]

Well building the torsion box is not the hard part. Keeping the pipe clamps from ripping the guts out of it is what concerns me.

Bill, on the Sunny and Warm Oregon Coast

[JR]

I'll be the opposite end of the pipe clamp is directly on the other side of the board on which it is mounted. The pipe needs to be only as long as the distance between dog holes. So that would define the size of the grid.

I assume the box is open on the bottom in order to provide access to the clamps. (I guess there could be a piece of ply covering the center of the bottom, offering some stiffness). If so, the top would be fixed in place - probably little cleats on the underside of the top, fixed to to the top and the case. Alternatively the box could be closed on the underside, with the pipe clamp going all the way through, but this could be awkward to operate.

The bushings are probably just to keep the pipe from wearing away the holes in the case. Look at the "pop-up" dog on the end vise. It has a bushing inserted to help keep the hole's shape.

[LarryG]

I think JR is right about the bushings: they're intended to keep the holes in the plywood from wallowing out, and possibly make the pipe clamps a little easier to slide in and out.

Regarding that, note that the paragraph immediately under the second photo concludes, "You might be wondering if pipe clamps have enough throw to be useful as a woodworking vise. They don’t. If you need to clamp really thick work, the pipe clamps can be slid out and locked in position to hold thick stock."

My best guess on what this means is that the pipes extend the full depth of the torsion box top (24") and can be slid out halfway or so (12", give or take: enough would have to remain within the TB to hold the pipes straight). They could be locked into the chosen position using the clutch on the other half of the pipe clamp fixture. This would mean that the TB cell in which the clutch is located would have to be open for access, but the entire bottom of the TB could be open as well.

It's an interesting design.

[LarryG]

Hey, I just noticed something. Look closely at the first photo of the bench, just to the left and right of the leg nearest the camera. There are what appear to be two chains hanging down with pull rings attached to the ends; these appear to be in line with the two pipes in the face vise. And there's a third chain visible down at the tail vise end of the bench.

I'll bet these are what operates the clutches on the face vise's pipe clamps. Bend down and pull the chain, slide the pipe out to the desired position, release the chain.

[JR]

There are what appear to be two chains hanging down with pull rings attached to the ends; these appear to be in line with the two pipes in the face vise. And there's a third chain visible down at the tail vise end of the bench.

I'll bet these are what operates the clutches on the face vise's pipe clamps.

Good catch, Larry. It's a bit difficult to get the proper perspective, but it looks like the chains are probably one grid length away from the side?

JR

[LarryG]

It's a bit difficult to get the proper perspective, but it looks like the chains are probably one grid length away from the side?

Yeah, I was wondering about that myself. The perspective does make it tough to tell. If they're hanging straight down, one grid back is probably right.

However, the chains might not be hanging straight down. They could be routed through guides, to bring them closer to the front edge so they'll be within easy reach. If so, the clutch fittings could be farther back.

And, on still further review, I now see the pull ring for the tail vise in the second photo.

[Gary Blum]

Hi everyone,

This is my first post here. My wife was surfing and came across this post and brought it to my attention. I do own a Ryobi BT3 saw so I guess I qualify for the forum!

The bench we took to Atlanta was a prototype but will be produced with only minor changes. The bronze bushings are set into the web frame of the torsion box. We use schedule 40 pipe which is more accurate than regular black pipe for the clamps. Along the length of this pipe we drill holes spaced at regular intervals. Between the two bushings in the web frame members is steel tubing which has a spring loaded locating pin welded on. The chain you see below is attached to this spring loaded locating pin. To adjust the pipe in and out rapidly you just pull the chain and move the pipe to the desired location and the pin will snap back in place. The pipe is 18", but could be up to 24" if you really need some capacity. Describing the process takes much longer than actually doing it. The clamp board is removeable so each of the pipes can be used indiviually as well and rotated 90 degrees for side clamping. The rest of the holes will accomodate pipe clamps which are used just like my Bench Horse-the tail piece is removed and the pipe inserted through to the other side and then the tail piece is put back on. This same procedure can be used going down through the top as well, depending on how many holes one wants in the bench top. The bushing you see on the one picture on the dog is actually a rubber o-ring which holds it at the proper height.

Hope this clears it up a little and if there are any other questions I'll be glad to chime back in to answer. Thanks a lot and this looks like a great forum. Glad I found it!

Kind Regards,
Gary Blum

[JR]

Well, Mr Bill, it looks like you've found the right guy to get answers from!

Gary, welcome to the forum! And thanks for being so forthcoming with your design information. I hope you'll stop by from time to time and contribute your ideas.

JSR

[BobSch]

Welcome to one of the best forums on the 'net. What do you do besides designing intriguing benches?

[Mr__Bill]

E-gads, I must have been really spacing out to not have seen the pull chains. Good catch, it does look like the tail end is the other side of the frame in the first cell. I expect that a TB made out of 3/4 BB ply may not need a full bottom skin. That would make it easy to position the clamps anywhere. The clamp holes seem to be 2 1/4" down from the top allowing for 3 layers of 3/4" ply for the top. IF the bottom two are glued the top one could be just screwed on from underneath allowing for replacement. One could even drill clamping holes in some of the center cells and then clamping through the table would be possible.

I bet the bushings are on the back side of the pipe holes, as JR said, they would give a bearing surface for the pipe running through the hole and for the tail piece against the ply. I'll have to look in a real hardware store the next time I'm in a big city to see if I can find something like that.

I think I would have to use pipe clamps that have the cam lever that locks the pipe in place. I can't see how the other type could be released with a pull chain.

Now the question is: How does one build a perfectly flat TB without a perfectly flat surface to work on? I am thinking I'll not be welcome on the kitchen counter for this project.

Here is a link to Blum's earlier version of the workbench.

Bill, on the Sunny Oregon Coast. Forcast is for 80 deg. today, a hot one, have to get out and enjoy the day.

[Mr__Bill]

Gary, thanks for the reply. Such a gentleman, even when I am trying to cheat you out of a sale by building my own using your creative ideas.

I think the steel tubing with the spring loaded locating pin is beyond my abilities to make myself. It is however a very clever way to solve the problems of using the pipe clamp's tail piece. I expect that when I build my bench that it will look more like your portable workbench*.

I am sure that my variations on the design will not make it better, it will however keep me entertained for a while and I hope yield a workbench that is at least usable and within my price range.


* ok, it won't be anywhere near as nice and as I will be using scrap and whatever is available, (Baltic Birch is a 2.5 hour drive away) I can only say, Inspired by and not cloned from.

Bill, on the Sunny Oregon Coast. Who once drove through your neck of the woods on his way to Lincoln from Minneapolis.

[Nilt]

Now the question is: How does one build a perfectly flat TB without a perfectly flat surface to work on? I am thinking I'll not be welcome on the kitchen counter for this project.

Luckily for you I found this link earlier today, huh?

Process for building a level worksurface on which to assemble a torsion box.