Wilton early 744 materials question

[rdenney]

Posted elsewhere but that thread coughed up a catalog page that in my beginner ignorance has attracted my curiosity.

The vise in question is a Wilton, but not exactly like any regular 744. The jaws are narrower at 3" with 2" jaw-screw spacing, pipe jaws are not provided, and the swivel lockdowns were plain nuts in the two examples that are otherwise similar. The casting numbers match the first iteration of the 744 4" Mechanics Vise. One notable difference is the thrust collar for the lead screw, which is a steel thrust plate against which the handle boss bears. The lead screw is retained in this thrust plate using a snap ring. More on that later.









Here is the catalog page that aroused my curiosity:

Note the use of steel for the guide bar around the lead screw. Also notice the "semi-steel" description of the main casting.

I watched some YouTube of a guy destroying a collection of vises by testing them to destruction, which I'm sure has been discussed here before. In all cases, the most common and earliest overtightening failure was when the steel guide bar yielded. You could tell this because the stress increased (more tightening) but the clamping force did not (because the steel was yielding). So, I count the use of a square steel tube guide bar on the above vise as a weakness--that's what will fail first--but also a feature--it will fail gently rather than projecting a piece of shattered iron across the room and dropping the workpiece on your toe.

The long threaded lead-screw nut on the Mechanics Vise is a feature--those did not see any thread failure in the testing. The other major failure point for lead screws was any hole therein for a lock pin or collar set screw or whatever. The Mechanic's Vise does not have that--on mine, the lead screw is retained to the thrust plate (which is screwed to the moveable jaw) by a snap ring that runs in a groove in the wider section. So, there is nothing in the lead screw than presents less cross-sectional area than the thread root. I don't know the strength of the steel used in Wilton lead screws, but if equivalent to a Grade 5 bolt (meaning: middle of the range), the lead screw strength should be 15-20 kips. The vise is only demonstrated to 8000 pounds (8 kips, and described on the next page of that catalog whence the above page came), but I think the guide bar will fail through yielding long before the lead screw breaks.

So, what's the opinion on "semi-steel", used to describe the main casting? It seems that it could mean anything within the general description of iron with scrap steel mixed in during the melt. This has the effect of reducing the carbon content, reducing the flake graphite/carbon but not too much, increasing the compressive and tensile strength, reducing the damping properties, and possibly improving ductility and toughness. Read: It's somewhere between plain gray iron and ductile iron. In terms of strength, it could mean anything, but then we generalize that gray iron has a strength of 30 KSI and ductile iron is twice that, when there are gray iron formulations with 60 KSI strength and a few ductile irons that are less. My guess is that "semi-steel" is mostly marketing-speak for "the good-stuff gray iron compared to the run-of-the-mill gray iron **** used by those compromisers over at Columbian." I note that "semi-steel" does not seem to appear in later catalogs, and certainly not in catalogs published since the departure of Mechanic's Vise production from these shores. Lately, they describe these vises as being made from gray iron, which is not necessarily a bad thing if appropriately designed.

What does this all mean? Beats me--mostly just a new guy who didn't see this discussion in a search about these vises and perhaps naively thought it was interesting. I think the bottom line is that the earlier Mechanic's Vises were intended to be thoroughly competent vises that would be more affordable than ductile-iron bullet models. They should not fail in spectacular ways, and should allow fearless tightening using the supplied handle and perhaps judicious use of a cheater for those not as capable of cranking down on the handle as some are.

Rick "much ado about nothing" Denney

 

[Roberts210]

Thanks for the interesting post Rick Denney.

 

[paulsomlo]

Had to look at your profile to confirm my suspicions - an engineer (takes one to know one). Keep posting, Rick - nice to see a new member contributing in a meaningful way.

By the way, I own that same vise w/5" jaws and really like it; I've added a thrust bearing, replaced the bent handle with a piece of 1144 Stressproof, done the "Parker handle mod", and replaced the warped jaws with aluminum soft jaws.

 

[Fierljeppen]

rdenney...Proceed at your own risk, you're entering the vise zone.

 

[rdenney]

rdenney...Proceed at your own risk, you're entering the vise zone.

Been there a while, but starting to get stern looks from the Redhead.

The inventory so far:

3” Wilton 74”3” Mechanic’s Vise, pre ‘75.

6” Columbian D58, like this one, except “Made in USA” is cast into the moveable jaw. Bought new for about a C-note at a tool flea market, but I don’t remember when—I think after I moved to Virginia in ‘98. The box said “Wilton” on it, so mid 90’s at the earliest. Durable enough, I suppose, and I’ve used it as a bending brake for 3/8 flatbar, helped with a engineer’s hammer, which is a non-trivial test. But it’s sloppy and the swivel locks have to be hammered to make them tight enough. The moveable jaw has at least 3/16” of lateral play and did so straight out of the box.

7” Brink and Cotton No. 178 woodworker’s vise. A cheapie back in the day, and probably made for the B&C label by one of the biggies (who probably made the same vise for a dozen other brands).



4” Doyle mechanic’s-type from HF. Supposedly 60 KSI ductile iron. Nicely finished for the price, and very little slop. Jaws align perfectly. I cleaned it up. I do not live in an area where one can find steals on vintage vises on Craigslist very often. Round, keyed guide bar.

5” Doyle multipurpose vise. As above, but a useful configuration.

11” No-name end vise for a woodworking bench. When my Armor bench top arrives, I’ll install this on one end. The B&C will go on the other end.

100mm no-name bench vise. Bought new, maybe at Sears, at least 40 years ago. An import cheapie for sure. Needs new jaw screws and the lead screw is stiff for one reason or another.

Chinesium cross-slide drill-press vise—perfect for my craptastic Clarke drill press with its 60 thousandths of runout (grrrr!).

The Columbian and the 100mm no-name are bolted to a bench in the old garage where I do my bicycle mechanics. They will stay there. The two Doyles will go on a “dirt bench”, where I will work on greasy car stuff. The Wilton 744 will go on the clean bench where I do clean work. The two woodworking vises will go on my carpenter’s bench.

Quantity over quality, in general. But they all will get used.

Rick “knowing HF gets little respect, but so far impressed by the Doyles” Denney

 

[rdenney]

The thrust mechanism on this Wilton "744" may or may not be typical. It does not look like other examples I've seen, but my experience is limited to photos others have shown that are not necessarily clear.

Here is a photo of the thrust plate and how the lead screw is attached to it:



The thrust plate is a quarter-inch thick punched plate, and it may even be a forging. The outside is machined flat, and the inside (the side sort-of showing in the photo) is mill finish. The plate is held onto the moveable jaw with two 10-24 machine screws.

The vise handle for the lead screw is machined down to a bit less than 1-1/8" in the part that goes through the thrust plate. A snap-ring is used to retain the vise handle and lead screw into the thrust plate so that it will pull the moveable jaw out when unscrewed.

So, primary tightening thrust is between the vise handle and the thrust plate. This is inadequate, and mine shows considerable wear on that interface. There is about 0.12" of gap between the vise handle and the thrust plate, so there is room for something else.

I therefore have gone shopping at McMaster-Carr. One thing I found was a "high-load oil-embedded iron-copper thrust bearing" which is oilite lubed with 90-wt oil and which is rated for well over 9000 pounds of thrust at low rotation. This will be Plan A. This one is 1/16" thick and will fit right in there with no modifications, to be worn into the currently worn parts in the fullness of time. But it would prevent further wear on the original parts and also allow easier tightening. These are just large enough to overlap part of the heads of the thrust-plate machine screws, so I'll notch the washer to fit around those heads, which will help retain it in position, trapped as it will be between the handle and the thrust plate. If I need to **** up a bit more space to ensure reliable retainage, I'll use one of the washers below, which brings me to Alternate Plan B.

I got sort-of on a McMaster roll, which happens to me pretty often. I found a needle thrust bearing rated for 4000 pounds "dynamic" (which I gather is rotation, which isn't that relevant to vises, or shock loading, which is also not particularly relevant as long as it is tight before hammering on something) and 16,000 pounds "static." It's designed for a 1-1/8" shaft and is 5/64" thick. Of course, they are expected to run on hardened and ground surfaces, so I added a couple of washers to go on either side, which are designed for this bearing and are 0.032" thick. The stack would end up 0.142" thick, so I'd need to do a bit of shaving on something, probably the thrust plate. I lack either a mill or a lathe, but I'll think of something if it looks promising when I get it. This bearing is strong enough, but not as strong as tapered bearings would be, and the jury is out as to whether the alignment is good enough that the needles won't just skid from not being squarely loaded. We'll see.

All this stuff was cheap enough to buy on a lark.

Rick "easy improvements without making drastic changes" Denney

 

[paulsomlo]

https://www.garagejournal.com/forum/threads/the-vises-of-garage-journal.44782/post-8426003

 

[rdenney]

https://www.garagejournal.com/forum/threads/the-vises-of-garage-journal.44782/post-8426003

Yeah, like that.

Rick “doin’ it without a lathe” Denney

 

[rdenney]

It’s done and this vise is installed.

The needle bearing was a perfect fit. I ground down the thrust plate on the side of my biggest grinding wheel to get rid of the previous galling, and that also made room for the bearing stack with very little lash. I need to lube it with heavier oil, but that’s in the old garage and I’ll do it later. Exposed as it is it will get gritty, but it’s also easy to blow out with an aerosol can and re-oil it. We’ll see how it does.

My clean bench has an MDF top so I used bolts with heavy washers underneath. It’s mounted with half-inch bolts—just a wee tad overkill but it looks right. I had to mount the back left bolt nut-end up because I got too close to the leg assembly, but the bolt was the right length to avoid a bunch of exposed threads.

I installed Wilton replacement swivel locks to get the handles, and slipped o-rings over the handle ends. No paint, but I did wire-brush everything that wasn’t painted.

Nice vise, and fun to bring back.









Rick “the oilite washers were too big” Denney