Leg vise Parallel Guide Adjuster by Ancora Yacht Service

[Derek Cohen]

For the past few months I have been discussing a parallel guide adjuster designed by Jim Ritter. My input has largely been devil's advocate while Jim sharpened up the design for production. I have no interest in this venture other than wanting to see a good product made available for others to use.


The leg vise parallel guide adjuster is an alternative to the St Peter's Cross, both of which enable a leg vise to function without the pin adjuster. No more stooping and setting the parallel guide for a specific width. Instead there is a single setting for all work pieces. In theory there should also be more pressure as the chop is more upright.


Yesterday I completed assembling the pre-production kit, and here are a few pics with my impressions.


From the front you will not notice any change to my leg vise ..





Close up you may note that I have replaced the steel screws with brass ..





From the side you will see a solid parallel guide and, above it, a chain ..





Solid paralel guide?!


Yeah .. in for a penny, in for a pound ... off came the parallel guide of my 6-month old leg vise ..





.. and replaced with this new, hole-less version ..





Inside the bench the chain mechanism can be seen ...





Outside ..





In all, including building a new parallel guide (which I do not expect others to do), the installation took a day.


So how does it work?


It grips ...





... and grips ...





.. and continues to grip ..





.. no matter how little there is to grip ..





Downside? The mechanism requires that the internal wheel guide is removed .. this one ..





As a result, there is a little more resistance in the parallel guide moving back-and-forth compared to before. The chop still moves smoothly, and the effort is similar to that of the Record #52 1/2 I had on my old bench. Of course, this may just reflect the need for a little fine tuning since the parallel guide is new. As it stands, this is a rejuvenated vise, one that promises to work with a much greater range and considerably less effort.


Once Jim gives the OK I will post a pictorial of how I installed the kit.


Regards from Perth


Derek

[Jim Koepke]

Once Jim gives the OK I will post a pictorial of how I installed the kit.


Regards from Perth


Derek

Looking forward to that and maybe even a little explanation of the inner workings. It looks like it could work with a cable and pulley set up as well as a chain.

jtk

[Derek Cohen]

Hi Jim

We discussed the use of a chain and pulley, since that was my idea as well. Jim had solid reasons why it would not work well - keep in mind that he spends his life dealing with the stuff. Hopefully, Jim will be along to explain.

Regards from Perth

Derek

[Jessica Pierce-LaRose]

Not knowing how everything is put together exactly, I may be wrong, but it looks like if you still wanted the wheel on the back, you might be able to mortise something in place behind the plate mounting the lower gear?

The photos make Jim's design make a lot more sense - it definitely "clicks" for me now - I was having a hard time wrapping my head around was going on before. I can see what was said about needing to make new gears - I haven't seen anything off-the-shelf that small before.

[Jim Ritter]

Thanks Derek great job as always. As to the cable... I thought about that but the ends would have to be swaged, that is expensive, it also creates a fixed length with a long turnbuckle that is harder to accommodate. After talking to many people about their vise arraignment, screw length, distance between screw and beam every one was different. Custom adjustability was important. The chain can be cut or added to if you make a mistake and cut it too short. Chain also has less stretch than cable.
I actually placed my lower wheel on the inside of the leg and the action is very smooth, until it is extended past about 9" but it still isn't bad. I also considered a slot down the middle of the beam with a smaller wheel inserted. But for me the wheel behind the leg works just fine.

[Sam Takeuchi]

That looks like a very promising system, yet very simple. Chain in tension keeps the vise upright? Does it stretch a bit when you are closing the vise? Does the vise face tilt at all? Any slack/slop at all?

[Jim Ritter]

That looks like a very promising system, yet very simple. Chain in tension keeps the vise upright? Does it stretch a bit when you are closing the vise? Does the vise face tilt at all? Any slack/slop at all?

The chain length is adjusted so that it always closes toe in so to speak. As full clamping pressure is applied the jaw comes parallel. Not much of what I would call slop.

[Sam Takeuchi]

The chain length is adjusted so that it always closes toe in so to speak. As full clamping pressure is applied the jaw comes parallel. Not much of what I would call slop.

This is really, really, really nice. Self aligning and all. Are there any issues and kinks to work out still?

I think it's the first time I felt excited about a vise of any kind.

[Todd Burch]

I may have to finally build a bench and put one of these puppies on it.

Jim, what cute name are you going to call this "Leg vise Parallel Guide Adjuster"? I think PGA is taken...

[Jim Ritter]

This is really, really, really nice. Self aligning and all. Are there any issues and kinks to work out still?

I think it's the first time I felt excited about a vise of any kind.

Thanks for all the excitement,that is exactly how I felt and my wife was wondering what was wrong. The last thing I did was standardize the sprockets for production,to try and rein in the cost of manufacture. What Derek installed is what I would call the easy install kit. I will offer it without the metal brackets to lower the cost. The upper sprocket would then be mortised into the leg as I did on my bench. Derek has the first with mounting brackets for the sprockets.

Haven't thought up a good name yet. Just been calling it the chain leg vise. Maybe a naming contest is in order. What do you think?

[Chris Vandiver]

Thanks for all the excitement,that is exactly how I felt and my wife was wondering what was wrong. The last thing I did was standardize the sprockets for production,to try and rein in the cost of manufacture. What Derek installed is what I would call the easy install kit. I will offer it without the metal brackets to lower the cost. The upper sprocket would then be mortised into the leg as I did on my bench. Derek has the first with mounting brackets for the sprockets.


Haven't thought up a good name yet. Just been calling it the chain leg vise. Maybe a naming contest is in order. What do you think?

"Missing Link"?
"Chain of Command"?

[Rob Fisher]

Any idea when we could see this on the market and at what cost?

And how about "Chain Stayed Leg Vise"?

[Jessica Pierce-LaRose]

I suppose another option to move the wheel further out would be to form some sort of U-shaped bracket after the lower sprocket holder, attached to the stretcher, and going over the parallel guide, sort of "pulling" down on that end of it rather than "pushing" from above.

[Bryan Schwerer]

Let me just beg you to give us a chance to order this before Schwartz writes an article about it and everybody goes crazy. Please, Please, Please!!!!

[Jim Ritter]

Let me just beg you to give us a chance to order this before Schwartz writes an article about it and everybody goes crazy. Please, Please, Please!!!!

Thank you for everyone's enthusiasm. It is very encouraging since I've never tried to produce anything like this before. Once I get the bids back from the machinists I can set a price and start taking orders to be delivered when the parts come in.