Lee Valley Twin Screw Vise--Followup *LINK*

Re: The "Rule of Doubling" applies...

William Duffield, on the Cohansey

>...AFTER taking into account the "Rule of Doubling."

Great article. How long have you been using the new vise? I still think I would have chosen a harder wood for the blocking above the screws, because Sequoia sempervirens is really soft, and I would not expect it to wear very well. Well, if you notice any increased sag in the future, it should be easy to replace.

Leather lined jaws...

David Barnett

>...for less wear and strain on the vise hardware and for a very secure non-marring grip. To keep things from sliding about on a hardwood benchtop when not using vises or dogs, I've used a sheet of leather, a 1/4" panel of masonite with glued sandpaper, rubber shelf liner (works great), and holdfasts.

Re: Lee Valley Twin Screw Vise--Followup

Wiley Horne

>Hi Wendell,

The Nicholson bench, p. 4 in The Workshop Book, did grab me. Also, two German benches, a 1500's model (p. 9) and an 18th century one (p. 22). Maybe that's how we all get started--some germ of inspiration. Beyond that, no research other than reading and thumbing through that book about 40 times, trying to mix and match features, and getting confused.

Finally woke up to the fact that the 'features' approach was gonna go round and round like a merry-go-round and never get to a stopping place. I needed to list every operation to be done at that bench, and figure out how to do it. In other words, work from the function toward the features, rather than the other way around.

On face planing, usually I catch the board between end vise and another dog, and plane back into the vise (left handed). If the stock is bowed, I shim it so it'll hold still in the vertical plane. On thin stock, I usually plane into a piece of wood (stop) held by the end vise.

On the tools....it's my hobby. Doesn't need to pay for itself.

Wiley

Re: Another question

Greg Betit, Crown Point NY

>The jaws on the leg vise on my 19th century bench are faced with 1/4" of leather. They work great. I have a hard time finding leather thick enough to face them (shoe sole leather would do fine, but just try to find a cobbler around here!), they are currently faced with a double layer of ~1/8" stuff.

I faced the patternmaker's vise on the other bench with 3/8" thick pieces of poplar- another pretty soft wood. They are held in place with 2 magnets for each face. I drilled holes with a forstner bit and glued the magnets into the holes. I think softer wood does give you an advantage, and when they get too chomped up, they're easy to replace.

Greg

Re: Lee Valley Twin Screw Vise--Followup

Wiley Horne

>Hi Bob,

I'm thinking a little differently about your situation than mine. Remember, I had to make those skinny holes for bearing because I had located the screw nuts so far back off the rear jaw face. I got myself into that fix.

You probably don't need to do that. Is your rear jaw something like 1-3/4" to 2" thick maple? If so, then I would suggest you consider mortising the screw nuts into the rear jaw (the 'Hank Knight' approach), so that you have bearing from the screw nuts right up to within 1/4" of the rear jaw exit. That beats anything else for support. And drawings are in LV's own twin-screw instructions. You can look them up on line, and download them if you have a printer--link to them from the twin-screw vise page. Couple that with the zero-clearance blocking, right up against the inner face of the rear jaw, and that's about the max. bearing you can get.

On the front (travelling) jaw, I don't know that you need to drill it for tight fit, or inset anything. You'll be able to judge that best yourself. What will be most important, I think, is to get the taper on the front face of the jaw right, so that the taper absorbs the play in the garter. I mention this because that garter is a little different than the one on the twin-screw--it doesn't seem to have as long a connection to the screw body. So the play in it may be different than with the twin-screw garter, and you may need to do some trial and error to get the taper right. I'd start with 3/32" of taper, and increase it if necessary. If you have a lunchbox planer, putting that taper on the vise face is real quick and easy, and it is explained in LV's instructions for the twin screw.

Hope this helps. Wiley

Re: Lee Valley Twin Screw Vise--Followup

Wiley Horne

>Hi Pam,

Rob has it exactly right--thanks Rob-- but I'll add a couple of things.

The main thing I am recommending is zero-clearance blocking above the screws, for the full length of the screw, and flush up against the inner face of the rear jaw. The reason is to have positive bearing on the screw at all times, so that it never has a chance to think about sagging. LV's standard details are to leave 1/16" clearance between the main screws and the blocking; the vise will surely work that way, but I don't want however much sag 1/16" of clearance will allow.

The rest is what Rob explained. I got myself into a fix by placing the screw nuts too far from the rear jaw outer face. Too much lumber in between. The equation in my mind was 'mass is good; more mass is better'. But that's not always right--the leverage of the situation says that you want the screw nuts as close to the rear jaw exit as practical. LV's instructions for mortising the screw nut into the rear jaw do precisely this. But this presumes you're following the 'standard installation' and have no other lumber in the way.

In other words, what Rob said.

Wiley

Re: The "Rule of Doubling" applies...

Wiley Horne

>Sir Wm,

Your words remind me of the other great rule of estimating......90% of the time is spent on the first 90% of the work; the last 10% of the work is what uses up the other 90% of the time. Or something like that.

Been using the bench and vise for two years. My thinking at the time on the redwood was that I might be overconstraining the main screws, and causing metal-on-metal binding in the screw nuts, because I was tapping the blocking in with hammer taps, and the screw threads were scratching the wood. I figured the redwood would be soft enough to let the screws 'find a level' that would minimize friction inside the nuts.

Luckily, the screws don't chew up the wood, but rather follow the same track and burnish it. But if I had it to do over, I would go with hard maple, because it turns out that what I originally feared was not a problem. So go with the better wood.

Thanks, Wiley

Thanks, Rob, deobfuscation complete. :)

Pam Niedermayer - Austin, TX

>

Re: Lee Valley Twin Screw Vise--Followup

Pam Niedermayer - Austin, TX

>Thanks, Wiley. In your article you say:

This is a good place to discuss a key point: In a standard LV installation, there is no framing behind the rear jaw. So the screw nut is let into the rear jaw, and in fact LV provides drawings for an option where the nut is mortised deeply into the rear jaw.

But the LV instructions show mortising the nut up to 1" into the skirt, if it exists. Seems to me the solution would be longer nuts, perhaps optional.

Pam

Thanks, Dean

Pam Niedermayer - Austin, TX

>

Re: leather

Pam Niedermayer - Austin, TX

>Thanks, David & Greg, sounds like a generally good thing to do.

Pam

Re: softwood vice jaws

Angus Barclay, in New Zealand

>Hello Pam,

I used softwood for my entire bench - because it is what is affordable and widely available here. The Record 52.5 face vice works just fine with softwood jaws for the type opf work I do and the way I do it.

regards

Angus Barclay

Re: Another question

Kevin French, Antrim NH

>I read that when I was building my bench. I used a piece of 3" pine for the face. I have Oak faces in my bench at work and it does feel like I have to tighten that vise more.

Re: Another question

Pam Niedermayer - Austin, TX

>Interesting, so there's a truth to it. Kind of a bummer, though. I've got this huge load of qs white oak just waiting to make up a bench, guess I'll have to devote it to furniture. Maybe some Port Orford would be nice.

Pam

Re: softwood vice jaws

Pam Niedermayer - Austin, TX

>Thanks, Angus. I noticed that my planing beam, made from 2 2x4 50 year old red pine (or whatever, maybe red cedar, took it from the house when remodelling), sticks a lot better than my official bench. But I'd thought that was probably due to the finish on the bench. Maybe I'll scrape off that finish, see what happens.

Pam

Re: softwood vice jaws

Warren in PA

>Back in the seventies I used an iron vise lined with white pine. As I recall it held the work rather well- it compressed a bit when screwed tight. It did get beat up and I reversed the liners once. Small pieces would dent the pine. Toward the end I had trouble holding narrow work at the very top of the vise. I haven't thought about it for over 25 years.

Soft wood would be alright for some purposes like resawing or holding only large boards but I wouldn't recommend it for general work.

Re: Lee Valley Twin Screw Vise--Followup

Joe Rogers, Northern Virginia

>I would consider using the UHMW for the blocking. Dense,low friction. Sizing may be a problem.JR

Re: softwood vice jaws

Steve Knight

>myself I prefeer leather. it grips better.

Re: Lee Valley Twin Screw Vise--Followup

Wiley Horne

>Hi Pam,

Good thought about extending the barrels of the screw nuts, and indeed that would save having to make the mortise. But. Things are as they are.

I am trying to put a spotlight on the LV mortising option because I didn't get the significance of it at the time I was making the install decisions. I got it in my head that the mortising was to allow another inch of jaw opening--which wasn't important to me. So I blew it off.

But now I see that the main thing the mortising does is give you bearing all the way to the rear jaw exit--and that's worth the time and effort.

Added benefits of the mortising are (1) a little wider jaw opening, and (2) it lets you get the blocking flush up against the inner face of the rear jaw, which is good in the zero-clearance option approach to blocking.

Wiley

P.S. I haven't forgotten your question below about the C&W plane--still trying to get to it.

Thanks, Warren.

Pam Niedermayer - Austin, TX

>

Re: Lee Valley Twin Screw Vise--Followup

Pam Niedermayer - Austin, TX

>Thanks, again, this has been a good learning experience for me.

I don't set deadlines for replies, take your time. :)

Pam

Re: Lee Valley Twin Screw Vise--Followup

Pam Niedermayer - Austin, TX

>You'd just need a thin layer, so most of the blocker could be wood.

Pam

Re: Lee Valley Twin Screw Vise--Followup

Joe Rogers, Northern Virginia

>Excellent thought Pam. Hadn't considered that.JR

Re: Another question

Todd Stock

>The leather available from Hand American is billed as 1/8", but is closer to 3/16". Enough leather to do a bench runs about $15. Elmer's Glue-All works fine for attaching the leather, and makes it easy to replace in 15-20 years. The conditioned leather makes a nice vise lining.

The link is:

http://www.handamerican.com/honeleather.html

Another option is a new leather weight belt, which runs a bit more ($25) for slightly thicker leather.

Re: Lee Valley Twin Screw Vise--Followup

Hank Knight in SC

>I glued 1/2" UHMW to a maple backing with West Epoxy annd then cut it to size and planed it to the necessary thickness for the zero clearance blocking. The epoxy works well, I can't separate the UHMW from the maple. Using this method, you can use any thicknbess UHMW you want.

Here's a photo of a cutoff I had left over.