New Leigh hold-down clamps: Workholding made easy

[Al Navas]

.

Christopher Schwarz made a terrific presentation at the Berea Hand Tool Conference in November: Forgotten Workbenches and Workholding.

During his presentation Chris covered workholding. As a result of this presentation, I started doing some serious thinking about my European style workbench, and how I could improve clamping of work pieces when hand cutting dovetails, clamping jigs in place, etc.

The existing setup was slow and cumbersome:

http://sandal-woodsblog.com/wp-content/uploads/2008/12/leigh-clamps-5.png

One option was to use holdfasts; but this meant drilling holes through the 3-1/2-inch thick bench top. And during The Schwarz's presentation, a little light went on in my brain. I remembered Leigh Industries had announced a new product not long before the conference in Berea: Their hold-down clamps (http://www.leighjigs.com/hold-down_clamp.php), available in two models.

You can read a terrific review of these clamps by Dean Bielanowski, at OnlineToolReviews.com (http://www.onlinetoolreviews.com/reviews/leighholddown.htm). I am not writing this to do another review; but rather, to share some uses I quickly found for these new clamps since I received them, 20 hours ago. In my opinion, these clamps solve many workholding problems at the workbench; they are terrific! Well, I did manage to include a quick review.

The two versions of the hold-down clamps:

Bench mount: This version allows use of existing bench dog holes and, therefore, would allow use close to the front edge of the bench. The bench mount is a quick, easy way to hold down even small work pieces:

http://sandal-woodsblog.com/wp-content/uploads/2008/12/leigh-clamps-2.png

A huge plus: The bench mount version is also used on the drill press! I have not tried it, but will dedicate one as soon as another clamp arrives.

Surface mount: The surface hold-down clamp provides another way of cutting dovetails at the bench:

http://sandal-woodsblog.com/wp-content/uploads/2008/12/leigh-clamps-1.png

Sometimes, clamping jigs can be cumbersome; it depends on the style of the workbench. My European-style bench, with the bank of cabinets below the stretcher under the top slab, created a challenge to use clamps. But holding down the FMT is no longer a challenge:

1. On the left side, the bench clamp:

http://sandal-woodsblog.com/wp-content/uploads/2008/12/leigh-clamps-3.png

2. And on the right, the surface mount clamp:

http://sandal-woodsblog.com/wp-content/uploads/2008/12/leigh-clamps-4.png

3. The FMT with both sides clamped - easy:

http://sandal-woodsblog.com/wp-content/uploads/2008/12/leigh-clamps-6.png

I now envision installing several anchors, to hold surface mount clamps along the front face of the bench. Think crochet (pronounced crow-shay) the easy way; but now you can have one crochet on the left, and one on the right-hand side. Great for edge-jointing, and a terrific way to hold a board on edge on the front face of the bench, in addition to using the face vise. I invite you to read several references to the crochet and its use in workbenches at the Woodworking Magazine blog (http://blog.woodworking-magazine.com/blog/SearchView.aspx?q=crochet).

I will not sell my D4: I have been asked several times if I want to sell my Leigh D4 dovetail jig, since I am improving my skill at hand-cutting dovetails. My reply is still that I cannot, and will not sell the D4; it is my workhorse when I make multiple drawers and large dovetails carcases. I am reserving hand-cutting dovetails for very small drawers, impossible to cut with the D4.


.

[Doug Shepard]

Al
Thanks for posting. I hadn't seen these before and need a couple more clamping anchor points on the back edge of my bench for hanging a Woodrat mounting box when in use. These look like they might be another option. I couldn't get your link to the Tool Review to work though (comes out with an extra "http://sawmillcreek.org/url=" in front of it) and found it here http://www.onlinetoolreviews.com/reviews/leighholddown.htm
then checked out the Leigh info http://www.leighjigs.com/hold-down_clamp.php

I was curious to see how it compared to the LV surface clamp
http://www.leevalley.com/wood/page.aspx?c=2&p=57059&cat=1,43838
I've got one of these on the front edge of my bench for holding the non-vise end of longer boards and it works great but the price on the Leigh is quite a bit nicer. The only down-side I see is that you cant use the Leigh in blind holes like the LV unless you go with the keyhole anchor version. The upside is that the angled clamp on the Leigh looks like it might be more out of the way for some work than the straight vertical post on the LV. It's darn nice to have another cool choice though.

[Al Navas]

Doug,

Sorry about the problem with the link. I corrected it, and it is now working fine.

You are right. It is great to have other choices. In the end, I believe the Leigh clamps have what I believe is the best (i.e., highest) clamping power of any alternative. Two of my machines, the Leigh D4 dovetail jig, and the Leigh FMT, have these clamps (by design). It is truly amazing how well they clamp down on the work piece.

But, as you noted, they cannot be installed in a blind hole. The nice thing about the bench mount version is that it will use just about any size bench dog hole, as they provide the fenders, etc. And one must drill the recess for the surface anchor itself. The benefits of drilling into the surface certainly outweigh any "disfigurement" to the bench itself :eek: . Plus, because the anchors are recessed, they won't interfere with any work on the surfaces.


.

[John Keeton]

Jorgenson makes a lighter weight version that seems to work well.
http://www.adjustableclamp.com/hd-1652.htm $16/pr. at Peachtree.

I am sure that the metal versions are higher quality, but depends on the need.

[Jim Becker]

Since my bench is covered with round holes, I much prefer the Gramarcy hold-fasts that I own for this purpose, but for someone with a square dog bench and a couple hold-down holes, this clamp method can be quite useful. The Leigh design you picture seems to bring some additional convenience from the traditional screw type clamp. Thanks for the pictorial!

[Al Navas]

You are welcome, Jim!

You have the *perfect* situation with your bench top, with so many round holes in it :cool:. I was considering the Gramercy holdfasts, too, as they have such good reputation and work in just about all circumstances to a maximum bench top thickness of around 4 inches, IIRC. I hated to drill so many in the thick bench top, but I still have to drill down about 5/16-inch to install the anchors. The benefit of having these clamps outweighted the cons of drilling into the bench; after all, it IS a bench...


.

[Jim Becker]

Don't rule out the holdfasts, Al. You can still place a few strategically located 3/4" round holes to take advantage of them...and they are as fast or faster to use than the cam-clamps since you set and release them with your mallet.

[Al Navas]

I just ordered some holdfasts, Jim. I held off long enough - and now I must drill the holes.


.

[Al Navas]

Jorgenson makes a lighter weight version that seems to work well.
http://www.adjustableclamp.com/hd-1652.htm $16/pr. at Peachtree.

I am sure that the metal versions are higher quality, but depends on the need.

John,

Great point!

I do have one question: Is it possible to install these clamps on a vertical surface, like the front apron of a workbench? There is no mention at all in their web site. And their stated load limit is 50 lbs. - I don't have a good feel for what this means as I work on the bench.

In my case, I have to use the surface mount version, as the bench top is 3-1/2 inches thick, and the apron is 4 inches wide. Thus, no place for a hole in which to install the bench mount version on the front apron.

Another reason I like the Leigh clamps so much, after using them for several years on the D4 dovetail jig, and later also on the FMT, is their enormous holding power. I don't know of a system that can do the workholding as well as these, short of a really good vise. The holding power is stated to be greater than bench clamps.



.

[Neal Clayton]

my only complaint with those leigh clamps is i really wish the handles were metal, rather than plastic. if you even slightly over-torque them, they just pop loose.

if there were an identical metal clamp available, they'd be worth upgrading to (if leigh is listening).

[Al Navas]

Neal:

I suggest you call the Leigh Customer Support folks, as it sounds like something might be wrong. I am certain they will recommend what to do to correct this problem.

I have used these clamps on the Leigh D4 dovetail jig, and on the FMT for years. Never had any problems with them. Your comment makes me wonder if the step washer is missing from the clamps. These are the square-ish pieces just under the cam lever.

The step washer is critical, in that it essentially holds the clamp together. I have never experienced the problem you mention, even when exerting significant torque, but never over-torquing the clamps.

Please let us know the outcome. Thanks!


.

[Neal Clayton]

i actually sold my FMT to another person here so he'll be getting it in a couple of days, i'll point him to this thread though.

and yes, the clamps on mine if they are over torqued simply pop loose. i never thought they might have a part missing, i just assumed a poor material on their part for the design.

[Al Navas]

Neal,

Thanks for your quick reply. How will you do your mortises and tenons now? Just curious, as this machine is a keeper.

I hope the buyer won't have any problems. If he does, I am certain he will call Leigh, especially after reading this thread.

Over-torquing definitely will cause problems. But I have never had a case where I had to try to tighten something so much that I actually over-torqued the clamps to the point of failure.

I actually cranked down so much that I was unable to turn the handle, and they did not fail. I did it as a test, to make sure I did not damage something at a critical stage in cutting dovetails with the D4.



.

[John Keeton]

Al, the Peachtree clamps have a simple plastic spin on nut that mounts from the underside, so if you could get to the rear of the 3/4" hole - no problem. However, I would caution that they are lightweight. I got them to do some simple holddown on the surface of my bench to surface plane or work on a piece of stock. Not sure I would want to depend on them with a power tool involved such as a router.

[Greg Hines, MD]

What I have in my benchtop are 4 different style hold downs. I have some larger diameter holes (about 1 1/8" as I recall) and screwed to the underside of the benchtop are 4 pipe flanges. A short nipple (I think I ended up with 9 or 12") screwed into this, and a deep reach pipe clamp can be used to hold things very securely to the top. Generally, I have used them for holding boards for routing edges, and my portable planer to the benchtop.

The biggest trick that I found is that the flanges need to be properly aligned, so what I did was routed a pretty severe roundover on the underside of the benchtop, so that it can be screwed in right-side up, which looks unnatural, but works fine.

Sorry, no photos, can make some this weekend for those interested.

Doc

[Neal Clayton]

Neal,

Thanks for your quick reply. How will you do your mortises and tenons now? Just curious, as this machine is a keeper.

I hope the buyer won't have any problems. If he does, I am certain he will call Leigh, especially after reading this thread.

Over-torquing definitely will cause problems. But I have never had a case where I had to try to tighten something so much that I actually over-torqued the clamps to the point of failure.

I actually cranked down so much that I was unable to turn the handle, and they did not fail. I did it as a test, to make sure I did not damage something at a critical stage in cutting dovetails with the D4.



.

i'm primarily making windows and doors these days, so it's much easier for me to cut tenons with my cope bits, and therefore i need a square mortise too (or more chisel work than i'd like).

i found a general 75-075 for sale used when i was in new orleans for thanksgiving so that made the decision to switch a lot easier ;).

i never had a problem with the FMT, and if i were making furniture i would have kept it. just not the most efficient way to do what i'm doing.