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View Full Version : Leg Vise, chain or crisscross



Mike Holbrook
03-12-2013, 10:47 AM
So right after I bought my Benchcrafted Leg Vise they came out with their crisscross attachment that I believe improves the action in the jaws. I have also seen posts by Derek Cohen and Jim Ritter regarding a chain mechanism for improving leg vise jaws. I think I read a brief discussion of the advantagws of each in some post but can not find it now. I am wondering if anyone is using Benchcrafted's crisscross that can comment on how well it works? I know Derek liked his chain devise but I can not find whether they ever became available for purchase or not? I think the old Glide Leg vise kit I have can be retrofitted to the crisscross, although I suppose I will have parts left over (the glide wheels).

I will call Benchcrafted about their new devise and my existing vise but would like to hear from fellow Neanders. I am about to start building my bench and want to sort out this last construction detail first.

Erik Christensen
03-12-2013, 12:11 PM
just finished a crisscross benchrafted leg vise bench - the action is sweet - a good spin of the handwheel will have the vise travel a couple of inches on momentum alone and the action is the same with jaws wide open or almost closed. If you haven't cut any parts you would be OK but the crisscross takes longer leg vise parts than the plans for the glide wheels and I think some parts are thicker to maintain a minimum thickness under the mortise for the crisscross

Jim Ritter
03-12-2013, 9:46 PM
The chain kits are available. Don't know if I can link it directly because I am the one selling them, but if you search "chain leg vise" on goole it will turn up links to several discussions about the pros and cons. To install the chain as a retrofit takes about 2 hours and the hardest part is drilling a 5/8" hole through the leg and the chop. Ask me anything you want to know, I'll tell you all I know.
Jim

Edit: John Donofrio installed it on his bench here http://www.sawmillcreek.org/showthread.php?196969-Post-production-roubo-build-thread

Mike Holbrook
03-13-2013, 7:34 PM
Thanks for posting Jim. Glad to see chain kits are available.

I have the original Benchcrafted Glide leg vise hardware but I have not started building the bench or vise yet. I was a little confused by what I imagine were the original posts Derek made about the chain devise. I think he was trying not to give away too much info. at that point. I have seen videos of the devise working on Benchcrafted leg vises so I know it works. I believe I saw three different kits available. I am wondering which is appropriate for my situation? Are there instructions for installation that would apply to the vise I will be making? Maybe installation is the same for all new installs? I thought I read somewhere that the chain does not work with the roller system that came with the older Benchcrafted Glide kit I have? Maybe I am thinking about the Crisscross, as it is larger, occupies more space...

I will try to call the company that I believe carries the chain devise. I'm just not sure if there is anyone there who can answer questions?

Jim Ritter
03-13-2013, 8:16 PM
Hi Mike, the chain is independent of the screw so it will work with whatever you are using. As to the glide setup you will not need the upper roller that is on the inside. The lower roller is still a good idea. My roller is on the inside of the leg, out of sight and works just as well. I have a long chop so there wasn't room on the outside.
There are three kits. The basic has you mortise the upper sprocket and make your own bracket for the lower roller. I placed my beam alongside the stretcher and it supports half the sprocket.
The intermediate kit includes stainless steel angle iron to hold the lower sprocket. You still need to mortise for the upper sprocket. That is not hard on a new build. The third kit includes stainless steel brackets for the upper sprocket also and is mostly for the retrofit on an existing bench where it would be difficult to crawl under to mortise the sprocket.
The wheels are not used with the crisscross because there is no beam. All the instructions are on the website.
I think I answered all your questions.
Jim

Edit: Mike I tried to send you a PM but your folder is full and will not accept new messages.

Jim Matthews
03-13-2013, 9:08 PM
Do you have the standard set up installed, or is this a new build?

I'm using the pinboard on the bottom, riding on a skate wheel.
It's beautifully smooth, and for the price of a cup of coffee.

ryan carlino
03-14-2013, 5:07 PM
I am making a split top Roubo and am trying out the 30mm steel rod and linear bearing. I consider this a solid third alternative to the traditional pin-in-the-guide method. There was an article on the Wood Whisperer's site about someone who tried it, so I thought I would give it a go. For $50 shipped, I got a 500mm long 30mm diameter steel rod and a linear bearing (from misumiusa.com). I just got it installed as a dry fit and it looks promising. The rod does not deflect in the bearing at all. I still need to glue or ?? the rod to the chop - still trying to decide what to use.

256962256963

http://www.thewoodwhisperer.com/articles/roubo-workbench-leg-vise-alternative-linear-bearings/

Jim Ritter
03-14-2013, 5:34 PM
Ryan, I've seen that before but I don't understand how it grips when it is sliding in a linear bearing? I would think the chop would have to be way out before it would jam. I'd love to hear you take on it.
Jim

ryan carlino
03-14-2013, 6:00 PM
Provided everything is mounted parallel/perpendicular (not super easy to achieve...), the linear bearing only allows the rod to move in one direction: one and out. When clamping, the chop wants to rack (top goes out and bottom goes in). In order for this to happen, the steel rod would HAVE to get out of parallel. The bearing prevents this from happening and the rod cannot bend.

In practice, I've noticed a deficiency in the technique when the steel rod is just press fit into the chop (I haven't had a change to glue or secure it). When I clamp something, the rod goes out of perpendicular from the chop (it's still perpendicular to the leg, thanks to the bearing). So, the rod is basically deforming the 30mm hole in the chop. At first I thought this whole thing would never work. In thinking about it, it makes sense that the rod should be fixed to the chop...I was jumping the gun by trying it during my dry fit (how could you not? :) ).

My plan is to epoxy the rod to the chop to stop this from happening. I'll clamp it so it is perpendicular and use plenty of epoxy on a scuffed up rod end. If that doesn't hold, a flange bushing would do the trick. I will admit my 30mm hole in the chop isn't perfect. It could be deeper and needs to hold the rod securely. Stay tuned if you want to hear more...I hope to get some free time this weekend.

Jim Ritter
03-14-2013, 7:15 PM
Yes Ryan, keep us up to date. I would think in the perfect world the rod should be a few off from perpendicular so it starts to jam just when the jaw comes parallel. There is a lot of pressure on that joint as you have see. Depending on the distance from the screw I measured 600 pounds at just over 12" distance. The further from the screw the lower the force.
http://i1135.photobucket.com/albums/m628/boatman53/33462096.jpg
Jim

Matt ONeill
03-14-2013, 11:30 PM
Mike,

I recently retrofitted my split-top roubo with the criss-cross. I already like it much better than the original glide. It was a fairly easy retrofit as well.

Here's my write-up: http://brokenfingerswoodworking.tumblr.com/post/44123722804/criss-cross

The only thing I don't love is how much longer the chop is. I saw an install on another forum (about vintage machinery) where the gentlemen had installed the criss-cross as close to the screw as possible; so close that he had actually removed a bit of the acetal bushing. This allowed his chop to be a bit shorter. No difference in functionality, I just thought it looked pretty nice.

- Matt

256997

Jim Belair
03-17-2013, 7:55 AM
Ryan, looks like there is a slider using a linear bearing commercially available in the UK. Schwarz blogged about it from Australia.

http://www.theenglishwoodworker.com/shop/index.php?main_page=product_info&cPath=65_71&products_id=264&zenid=2imoh1kji9ec520o9i6vja6fu6

Mike Holbrook
04-03-2013, 9:15 AM
I called Jim at Ancora Yacht and after talking to him I decided to order his chain kit.

My reasons for going with the chain instead of the Crisscross:
1) the chain is a smaller devise, less that may be in the way
2) easier to install, offering multiple install options
3) most of the hardware for the chain system is on the back of the leg rather than between the leg and jaw
4) great support materials from Jim, Derek has posted a great deal on the chain on these pages, Jim offered his personal support should questions arise
5) Jim is very easy to work with, offering super service and support
6) I like to support those who work to solve issues that posters here find challenging
7) LV and LN have used chains successfully in bench vise designs before
8) the chain installation does not require the large mortises in the leg and leg jaw

Curt Putnam
04-03-2013, 1:54 PM
Good move! Why is it a good move? Because I did the same thing (which of course makes it a good move.) :D

Jim Matthews
04-03-2013, 6:14 PM
Good move! Why is it a good move? Because I did the same thing (which of course makes it a good move.) :D

I find the smartest people in agreement with me.
Why are so many idiots lined up in opposition?

Problem is, there are fewer of the former and ever more of the latter.
It's baffling, really. Maybe my guidance counselor was right, after all.

Kurt Cady
04-03-2013, 6:45 PM
Mike your inbox is full...


I called Jim at Ancora Yacht and after talking to him I decided to order his chain kit.

Interested in selling the components for the rollers and pin that came with your kit?

Mike Holbrook
04-07-2013, 1:34 PM
Sorry Kurt, not sure why, I removed a bunch recently. I went in and removed most of them this time so I should be good for a while.

Kurt Cady
04-08-2013, 9:06 AM
Sorry Kurt, not sure why, I removed a bunch recently. I went in and removed most of them this time so I should be good for a while.

Still says its full? Weird.

Since you ordered the chain kit, are you interested in selling some of the components you don't need, Like the roller hardware and the adjustment pin hardware they send with their kits?

Terrie Noll
09-04-2013, 2:23 PM
On gluing a steel rod into the chop, they make them with a threaded end so you can bolt the rod through the chop. Think it might hold better.

Tom Millington
09-05-2013, 9:43 PM
I'm very happy with my chain leg vise. I never have to think about it, the vise just works which is he best thing I could say about any tool!

Jim Ritter
09-05-2013, 11:31 PM
Thanks Tom, yes one does just forget that it is there, and you can concentrate on the job at hand.
Jim