Veritas twin-screw or ?

Re: Veritas twin-screw or ?

R.J.Whelan

>Bob ... as long as the movable sections of the two vises aren't tied together it isn't a big deal to tighten two independent vises - I had such an arrangement for dovetailing wide boards and it worked fine ... rj

Re: Veritas twin-screw or ?

Denny

>Bob,

I'm planning on doing the same. You might want to take a look at the latest FWW article "A Benchtop Bench", using veneer screws. You can see this setup in action at the FWW website. I'm going to give it a shot with regular screws, two are on their way now from LV.

Denny

Re: Veritas twin-screw or ?

Bob Fawcett

>Thats just what I was thinking. I plan to use 2 of the screws that LV sells for tail vises. (70G01.52)

If I can I will adapt them for chain or belt drive. Otherwise I will just have to turn both screws. This may skew the front jaw some if I don't turn them equally, but I don't think it will be a problem. The old hand screw clamps work that way.

Re: Veritas twin-screw or ? *LINK*

Wiley Horne

>Bob,

I've attached a link to a thread over at Roger Nixon's site, where a fellow has built a bench with the uncoupled twin screw design. You might want to email him to check out his experience with it. If the link doesn't open, Roger may have to come by with the key.

Having the two screws independent of each other is a good thing in many situations. In fact, LV designed their twin-screw so that it would uncouple, as needed, and this is an essential feature.

One thing I would suggest you think about is whether it is important to put blocking under the vise screws to prevent jaw sag. I have my regular LV twin-screw vises installed with blocking all the way from the screw threads to the underside of the bench, and would recommend that others do the same. Another fellow--was it Hank Knight?--posted photos not long ago on this site showing an installation of blocking. You might find this kind of blocking useful in your design, too.

Wiley


Benches; including independent twin screw vise

Re: Veritas twin-screw or ?

Denny

>I ordered those same screws, they won't get here until the end of the week. I expect some significant droop, so I'll probably end up using some UHMW blocks to keep things in place.

Wiley,

Frank Mutchler in Colorado Springs

>thanks for a great link. It really helps me understand how a bench can be used. I've never been fortunate enough to watch someone using a bench and every photo from that link was eye opening for me.

Re: Veritas twin-screw or ?

Bob Fawcett

>Wiley,

When you say block, I assume you, mean a block between the bottom of the bench top and the top of the screw threads. Is that correct?

Thanks for the great linkl.

Re: Veritas twin-screw or ?

Wiley Horne

>Bob,

Yes, that's right. When you get the vise installed, close the jaws and set the jaw level exactly where you want it. Then install the blocks to lock the system in place. Must have been about a month ago, Hank Knight posted a photo of the installation on his bench. He used UHM-whatever. I used redwood blocks, which is probably not as good, but it may not be too critical. I started a bit oversized and then planed the blocks down until until I could lightly tap them in between the screws and the underside of the benchtop. Then screw them into place. If you use wood, the screw threads will cut a track across the wood surface, and then follow the same track every time thereafter, and won't shred the blocking. And it doesn't introduce too much friction.

Something to think about, in addition to overcoming jaw sag, is that you'd like the screw to pass level through the nut to minimize long-term metal on metal wear between screw and nut.

Wiley

Talking you out of it

Adam Cherubini

>It seems like a good idea doesn't it. It was my idea too, and the first vise I built. Trouble is, it doesn't work worth a darn.

You mentioned clamping work vertically. That it will do, as long as the apron its in is very very stiff and the work passes between the screw centers.

Here's the problem; Vises like this including the vertias twin screw rely on garters to stop the jaw from rotating. If those garters were perfect, so that no rotation was possible, the competing screws would bind. I thnk the veritas garters are made tight such that the chain is necessary. The two I played with were certainly tighter than the german screws i bought from H-H.

Its only fair to mention we've had this discussion before, and many, many people disagree with me. My argument comes down to this: These twin screws don't allow you to clamp stock on top of the screws (so using this is an end vise is out) because the garters are sloppy (or will be soon- its a very close couple), but they are too tight to allow you to clamp angled stock.

I posted pictures of my twn screw doing both exceedingly well. I suggest you ask someone, maybe the guy that posted those nice pics on Roger Nixon's site, to take some pictures for you. Place a 1X4 on top the screws and clamp it. Take a picture of the side view (showing the jaw tilting). Then take a top downpicture showing the vises ability to clamp angled stock.

Maybe I'm totally wrong. Maybe I don't understand simple physics. But this was a good lesson early in my woodworking life that you don't need too repeat. So don't take my word for it: Take a look at how each vise, any vise, handles racking and off center clamping etc. You may well find (as I did with great frustrtation) that the vises everybody uses and loves, just don't work with hand tools.

Good luck,

Adam

Re: Talking you out of it

Bob Fawcett

>Adam,

Thanks for the reply. A couple of questions.

First, What exactly are "garters"? I don't know the word in this context.

Second, Wiley mentions "blocking" the vise in a post above. He installed blocks between the top of the screws and the bottom of the benchtop to prevent the screws from allowing the top to rack down. This sounds like a good idea and could maybe be taken a step farther by installing a couple of UHMW blocks bored to the size of the screw. This would help stop movement in both the vertical and horizontal directions.

You said "I posted pictures of my twn screw doing both exceedingly well." Is that a Veritas or one of your own construction?

Thanks again.

Re: Talking you out of it

Dean J in MN

>I'll chime in, seeing as I have the Veritas on my bench... Note, I'm refering to the vise setup as a face vise, not an end vise. It wasn't clear to me what Bob had planned on?

Here's the problem; Vises like this including the vertias twin screw rely on garters to stop the jaw from rotating. If those garters were perfect, so that no rotation was possible, the competing screws would bind. I thnk the veritas garters are made tight such that the chain is necessary. The two I played with were certainly tighter than the german screws i bought from H-H.

I have had the chain off of my Veritas -- It is workable, however you have to keep your screws within about 2 full turns of each other. Not ideal, and nowhere nearly as well as a garterless setup.

Its only fair to mention we've had this discussion before, and many, many people disagree with me. My argument comes down to this: These twin screws don't allow you to clamp stock on top of the screws (so using this is an end vise is out) because the garters are sloppy (or will be soon- its a very close couple), but they are too tight to allow you to clamp angled stock.

I'd reword that a bit... :) You can clamp slightly angled stock with the Veritas. No where nearly as angled as your wooden screw vise however. Also, if you keep the screws close to the top of the bench you can clamp things on top of the screws. Again, I'll qualify that with not nearly as well as a wooden screw garterless twin screw. It will rack, the above setup just tries to minimize the situation. As you said we can't beat physics. Using the Veritas as a tail vise with dog holes on top of the jaw as shown in the catalog is questionable, it makes a bad situation worse. I can't see it lasting very long to be honest.

My twin screw isn't perfect, and when it bugs me enough I can pull it off, drop out the nuts, slide in wooden nuts, find someone who will turn me nice wooded screws with large heads. I wonder how long it will be before I do just that.... I went in knowing it wasn't the perfect solution and designed things in hopes that I can change over when/if needed.

-Dean

Dean or Adam or anyone

Bob Fawcett

>Can someone explain what garters are in this context. I can't find it in a dictionary or on the net.

Dean is your twin-screw blocked?

Thanks

Re: Dean or Adam or anyone

Dean J in MN

>

Can someone explain what garters are in this context. I can't find it in a dictionary or on the net.

On the veritas the garter is the black "dohickys" which you attach your jaw (front jaw) to. The jaw moves with the screws. You unscrew and the jaw moves out with it, it is attached.

In garterless vise the jaw is floating on the screws. The jaw does not move out when you unscrew the screws.

Dean is your twin-screw blocked?

No. I buried the screws (and nuts) in the top. My top is 4-1/4" thick, the screw's centerline is about 2 inches below the top of the vise. My front jaw is the same size as my top, 4-1/4". (Go

-Dean

Re: Dean or Adam or anyone

Bob Fawcett

>Thanks.

Since I am thinking about adapting 2 tail-vise screws to create a twin screw type vise, I could make the front jaw free floating like that. I plan to use it as a front vise. Most of my work would be dimensional parts. I can't think of any common parts I would do that are odd shapes. I am not sure I see an advantage to making mine garterless. It seems like that would also make it difficult to clamp only above the screws, or try to use dogs in the jaw.

I will probably build it with the garters.

Thanks again

What's correct and what isn't

Wiley Horne

>To Adam and All, with nothing but good will:

I think Adam's twin screw vise is excellent, and would not reenter this thread but for one statement that he makes in advancing his design over LV's:

_____________

"My argument comes down to this: These twin screws don't allow you to clamp stock on top of the screws (so using this is an end vise is out) because the garters are sloppy (or will be soon- its a very close couple), but they are too tight to allow you to clamp angled stock."

___________

My everyday experience in using an LV twin-screw for an end vise is that you certainly can clamp stock above the screws, and the work will be held squarely and very firmly. The vise will not gap open at the top because there is a 2-degree slant built into the face of the moveable vise jaw (nothing to do with the garter holding the jaw rigid). Within the week I will show this forum a picture of this, as Adam requests (my camera sat down in a pool of shellac, and I'm fixing it).

Adam's statement that the LV twin screw can't be used effectively as an end vise is not so, and this is easily demonstrated. Again, there is a slight opening of the jaw under load, but this is accommodated by the 2-degree angled jaw face. It works well.

Adam and Dean are absolutely correct that there is a tight limit on clamping angled stock, and a chair leg (for example) would be too much angle in my estimation.

As a philosophical comment, I don't know why it is important to knock other people's tools and methods in order to advance one's own ideas and methods and ego. Especially if arguments have to be stretched beyond their elasticity limits to do so.

Wiley

HEY! Play nice Wiley!

Adam Cherubini, NJ

>Play nice or we'll make you use the LV micro adjust marking gauge!

You raise a lot of good points. Like I said, you can't argue with physics, but you certainly can (and I'm glad you did) argue with the extent to which they effect function.

I'm looking forward to your photos. It may well be that the 2 vises I saw were worn, defective, or improperly installed. Or it could be that I was just plain wrong. Despite my collosal, hollywood-sized ego, it does happen occasionally (though as you know I usually ignore it, then focus all attention back on me).

Seriously, I'd really prefer to change my mind on the subject since not everyone (like Dean) has access to wooden screws. And giving others the opportunity to work more like me is an important community service, as you and others have recently noted. Afterall, I'm an egomaniacal freak bent on destroying all metal planes and pizza cutter marking gauges. I won't rest until Veritas' tool catalog looks exactly like the Benjamin Seaton toolchest book (oooh-that's a little too close for comfort there- that's taking me places I want to go)

The only other serious point I think is worth addressing is how stiff the vise is to push on vertically. Maybe, open, say...4" or so. See I begin every planing operation with a good bit of toe pressure (and I think that's typical). With a conventional tail vise, you've got pretty good vertical support, but the twin screw (regardless of its design or material) can only take that toe pressure load in screw bending. How does that feel to you? Does the front of the board ever lift up? Again, of course it deflects. That much is simple mechanics. I didn't like the feel of the vises I played with and that was a few years back now. That could have been a function of the apron stiffness, or blocking.

And if I can say one more thing, and then I promise to shut it:

I started with a metal twin screw. That was my first vise. I thought it was a great idea. I tried the angled jaw thing and the blocking and it just didn't work. Being an egomaniac, I was shocked that my superior intellect, not to mention my 2 engineering degrees, had produced such crap and I began to wonder if there was a better design (couldn't be) or if all vises had similar problems. I found that many vises, and in some cases, the vises people rave about, really didn't work all that well. Certainly not better than the low tech alternatives (especially the leg vise, which in my opinion handily out performs the standard record vise.)

So I must say I was quite pleased to hear the exceedingly mannerly Mack Headley quietly complain about his vise. When you look at those vises (Nicholson bench vises), it seems a preposterous design, frought with all the inadequacies that we have discussed here. So I felt so validated and superior when I saw him fussing with it.

So bottom line: its really not everything 18th century that's superior, just my version of 18th century stuff. And if you don't believe it, I'm just going to have to make you wear the funny hat until you do!

Adam

-boy that was fun writing that.

Re: What's correct and what isn't

Todd Stock

>The elastic limit of a WC 'discussion'? Checked MIL-HDBK-5H and found nothing, which is to say, no statistically based limit to any argument.

I'm certain that at one time or another, most of the curmudgeons here have been acused of "...not planing well with others..." Nothing new, then, eh?

But seriously, it seems like the argument for dual screw end vises revolves around clamping oval panels and such. Is it really such a great idea to joint across the width of the bench, versus along the length?

Now that I've been advised that I've likely never used a well-tuned saw, it's one short step to having never used a decent bench. I guess I need a refresher on twin screw end vises.

Re: HEY! Play nice Wiley!--LMAO!

Wiley Horne

>Adam!

OH NO, anything but the LV microadjust pizza cutter thingy! LMAO at Pythonesque punishment by Adam (but no comfy chair).

Well, I'm down for what you say. Let's just measure the various deflections and find out what's what. What I have is the LV twin. I'll get photos and measurements that you can see of (a) how much angle correction is permitted, (b) how much (if any) gap opens at the top of the jaws when clamping a 1x6, (c) how much deflection downward of the front jaw (outer edge) is there when it's 5" or 6" open, with and without load, and under load, with a heavy weight sitting on it, simulating planing force, (d) when clamping boards vertically in the space outside the screws--and I do this a lot--how much horizontal deflection is there, and does the vise maintain grip all the way to the edge? (e) anything else anybody wants to see.

It'll take about a week.

Wiley......hoping Adam's not gonna get after me for using feeler gauges and Starrett stuff to measure these deflections (<:).

Re: HEY! Play nice Wiley!--LMAO!

Alan Bierbaum

>In keeping with 18c measurements:

You may only use a folding ruler ( but not more that 2' of it) and a calibrated hemp rope (do NOT smoke the rope).

Adam does not like my bench either.

Alan, ducking and running in Denver

Re: HEY! Play nice Wiley!

Bob Fawcett

>WOW! Now you have done it.

I guess I'll have to try using a twin screw I build myself as a combination face and end vise anyway, you talked me into it ... or was that out of it.

Oh well, I guess I'm just out of it anyway.

Re: HEY! Play nice Wiley!

William Duffield, on the Cohansey

>Two degrees? To what precision? I'll agree that if the top of the jaws meets first, it will hold flat wood better tha if it doesn't, but�

If you aren't sure of the optimum angle, just get an Emmert. It has a lever and an auxiliary jaw that will allow you to dial in whatever angles you think you might need. It does NOT come with a vernier, however, and you still have to try it out and fiddle with the adjustments to be sure of a firm grip on the stock.

The other issue discussed, with the use of the VTSV as an end vise, also has a viable workaround. If the jaw wants to deflect downward, lifting the aft end of the planed stock upwards, just put a block of wood between the dog in the vise and the back end of the stock being jointed. It has to be long enough to span the opening of the vise jaws. All the deflection from horizontal will then be taken up by this block of wood and the dog. The back end of the board is then fully supported by the top of the bench. If it still wants to lift, just add a little bit of bevel to the bottom of the face of the spacer block.