Monarch 225 Bench Vise

[Maui]

I just picked up this very large Monarch 225 bench vise yesterday, and as you can see it's still in the trunk of my car. It has jaws that measure about 6 1/2" in width, and is very heavy. My guess is the weight is around 135 lbs. Some yahoo repeatedly used the top of slide as an anvil decades back, and cracked it at the tail end. But the crack is tight and can be repaired. Otherwise it is in beautiful condition. I plan on restoring it soon. Does anyone know what the original color is supposed to be?

 

[tool_scrounge]

As you know, Monarch was a brand of Prentiss made vises. After seeing so many Prentiss vises with the same crack, I can only conclude they had a mold design problem which led to a nit line defect in that location. I have seen those vises with no hammer marks and the same crack.

 

[Maui]

I have several Prentiss vises with no cracks at all in the slide. The top of the slide on these vises were designed to be thinner than the comparable vises from other manufacturers, which made them more prone to cracking if abused. And the slide on this one clearly was abused because it was used as an anvil. The materials from which these vises were cast may have played a part in this too.

 

[1982fxr]

I've read that the crack on those was from improper cooling at the foundry.

 

[Maui]

I've read that the crack on those was from improper cooling at the foundry.

That's one theory. But if they cracked before leaving the foundry, they probably would never have been shipped out - the workers would have seen them. And a customer certainly would not have bought one with a cracked slide.

 

[neophyte]

That's one theory. But if they cracked before leaving the foundry, they probably would never have been shipped out - the workers would have seen them. And a customer certainly would not have bought one with a cracked slide.

Improper cooling could cause high stresses in the casting.
Those stresses could eventually lead to a crack once the vises started being heavily used or tightened.
This is like glass that has been improperly annealed after forming and cooling.
The glass can later just explode when it heats up from sunlight.

 

[1982fxr]

That's one theory. But if they cracked before leaving the foundry, they probably would never have been shipped out - the workers would have seen them. And a customer certainly would not have bought one with a cracked slide.

If they still worked fine they could have just discounted them. No different than buying any other factory seconds, dented soup, etc.

There are so many examples with no witness marks back there...

 

[drivesitfar]

I think Monarch vises left the factory with a shiny black that was sort of a Japanning style finish. there were a few vises on the vise repair 101 thread that talk about Japanning if you want to try it. I think it's involving a black tar like substance if memory serves me.

I've got more than a few Prentiss vises without cracked slides, but yes they seemed to crack more than other brands. I can't say I've ever seen a cracked slide on a Rock Island or old Reed.

good luck with the crack repair and lots of those mentioned on the vise repair 101 thread too if you need any ideas or help. I think the best one I saw was KMScott cutting a V into the slide after drilling a hole at the end of the crack. then filling with weld and machining it flat.

 

[Maui]

Improper cooling could cause high stresses in the casting.
Those stresses could eventually lead to a crack once the vises started being heavily used or tightened.
This is like glass that has been improperly annealed after forming and cooling.
The glass can later just explode when it heats up from sunlight.

I am a metallurgist. I understand the casting process. The top of the slide does not undergo any significant amount of loading during normal use.

 

[neophyte]

I am a metallurgist. I understand the casting process. The top of the slide does not undergo any significant amount of loading during normal use.

Wouldn’t the top of the slide be under tensile forces, were the bottom of the slide would be under compression?
Isn’t the major issue with grey iron that it has high compression strength, but significantly less tensile strength, which is the reason early cast iron structural beams were actually an inverted T beam?
Could the forces on the cast iron slide cause the center of the inverted U shaped to experience extra tensile forces in the center of the U, particularly if there were residual stresses left over from the casting process, that could cause that center to crack?

 

[Shiftless]

I’m with Maui on this. In normal use, I can’t imagine much stress on the end of the slide. If the jaws were opened up all the way to clamp something big and then some gorilla with a BFH started pounding on the object near the point where the dynamic jaw is holding on, there would be a lot of stress on the end of the slide. (And other parts of the vise as well)

Years ago I sold a Reed 4C to a guy who owned and operated a custom diesel exhaust shop. He told me that the 4 gorillas (his words) that worked for him had broken a lot of vises recently and he was tired of buying new ones. I told him that the 4C was probably up to whatever those guys would throw at it. He just smiled, handed me a wad of cash and drove off in his diesel Excursion.

 

[1982fxr]

I think Monarch vises left the factory with a shiny black that was sort of a Japanning style finish. there were a few vises on the vise repair 101 thread that talk about Japanning if you want to try it. I think it's involving a black tar like substance if memory serves me.

I've got more than a few Prentiss vises without cracked slides, but yes they seemed to crack more than other brands. I can't say I've ever seen a cracked slide on a Rock Island or old Reed.

good luck with the crack repair and lots of those mentioned on the vise repair 101 thread too if you need any ideas or help. I think the best one I saw was KMScott cutting a V into the slide after drilling a hole at the end of the crack. then filling with weld and machining it flat.

I think you're right about that shiny black factory finish.

 

[neophyte]

I’m with Maui on this. In normal use, I can’t imagine much stress on the end of the slide. If the jaws were opened up all the way to clamp something big and then some gorilla with a BFH started pounding on the object near the point where the dynamic jaw is holding on, there would be a lot of stress on the end of the slide. (And other parts of the vise as well)

Years ago I sold a Reed 4C to a guy who owned and operated a custom diesel exhaust shop. He told me that the 4 gorillas (his words) that worked for him had broken a lot of vises recently and he was tired of buying new ones. I told him that the 4C was probably up to whatever those guys would throw at it. He just smiled, handed me a wad of cash and drove off in his diesel Excursion.

The slide is an inverted U profile.
Under high clamping pressure, especially with the jaw opened wide, I would expect the forces to cause the lower ends of the inverted U to spread slightly, creating a tensile stress zone in the center of the Inverted U.

 

[American Locomotive]

That's one theory. But if they cracked before leaving the foundry, they probably would never have been shipped out - the workers would have seen them. And a customer certainly would not have bought one with a cracked slide.

That's wishful thinking, IMO. QA/QC was known for being bad industry wide back then. Cars, machinery, equipment. Lots of good 'ol American iron was actually very crude. Many of those old American machine tools you've seen with beautifully smooth castings? All body filler hiding lumpy, porous castings. Lots of people restoring Bridgeports Milling Machines have unfortunately found this out when taking them down to metal for refinishing.

While I have no proof they did, it wouldn't surprise me one bit if they shipped cracked vises to customers - provided they deemed the crack "cosmetic" and whatever finish they applied would sufficiently cover it.

 

[BlackVersa2]

There are plenty of examples of prentiss vises without cracked slides that exist. I own a few myself.

Usually when a slide cracks, it will make the slide slightly wider and will give resistance when opening/closing. I just can't see workers squeezing cracked slides into vise bodies when new.

 

[Shiftless]

I have 6 Prentiss vises (one is a Monarch) and none of them have cracked slides. But I realize that this doesn’t PROVE anything,
But when I got them, they had all been used but evidently not abused.

 

[Maui]

That's wishful thinking, IMO. QA/QC was known for being bad industry wide back then. Cars, machinery, equipment. Lots of good 'ol American iron was actually very crude. Many of those old American machine tools you've seen with beautifully smooth castings? All body filler hiding lumpy, porous castings. Lots of people restoring Bridgeports Milling Machines have unfortunately found this out when taking them down to metal for refinishing.

While I have no proof they did, it wouldn't surprise me one bit if they shipped cracked vises to customers - provided they deemed the crack "cosmetic" and whatever finish they applied would sufficiently cover it.

I own several Prentiss vises. None of them (with the exception of this Monarch 225) have cracked slides. For example,

 

[American Locomotive]

I own several Prentiss vises. None of them (with the exception of this Monarch 225) have cracked slides. For example,

I mean obviously they're not going to be in the business of purposely cracking and shipping out vises, but they also wouldn't have been in the business of scrapping usable parts that might only have superficial defects. As others mentioned, selling defects at cut-rate prices was a common thing back then, too.

The fact that it's common enough where cracked Prentiss slides is apparently a "known thing" makes me think more than a couple may have left the factory cracked, or at the very least an issue with their casting process or design.

Lots and lots of Bridgeports out there with cracked and flaking off casting filler....

 

[Shiftless]

Since we‘re talking about Lion Heads, here is mine. It’s an old through the bench mount swivel model.
I‘ll include some other Prentiss non split tails.

 

[Maui]

These aren't Bridgeports. And you have no proof whatsoever to back up the opinion you expressed that Prentiss sold their vises with cracked slides. Word gets out pretty quickly when manufactuers distribute defective products, and people usually avoid them as a result. Prentiss was one of the leading vise companies in the United States for nearly a century. And several people here, including myself, own multiple Prentiss vises, some of which are over 100 years old, that have uncracked slides. The Monarch 225 vise that I own does have a cracked slide, and that can be reliably explained by abuse.

 

[American Locomotive]

Look man, I'm not trying to offend you or disparage your favorite vise brand.

I have researched late 19th and early 20th century manufacturing extensively. In the late 1800s and through the early 1900s, manufacturing in general was a very laborious and expensive. Casting technology and metallurgy wasn't like it is today. Manufacturers (of all kinds) would go through great effort to save castings and try and keep scrap-rates low because of the immense cost involved.

Often sub-standard products would go through if they could be cleaned up enough to work. I've taken apart so many things from the late 1800s and early 1900s that had all kinds of manufacturing defects covered up or blatantly just ignored by the manufacturer. You can find lots of photos of seemingly un-abused Prentiss vises with cracked tails. As it sits, Monarch vises in the Prentiss catalog were significantly cheaper than the equivalent size "Bulldog" vise. There's probably reason for that.

I'm not saying for sure that Prentiss shipped vises with cracked tails, just that it wouldn't surprise me if they did - as many manufacturers did just that. It also wouldn't surprise me if they knowingly shipped vises with marginal castings. There have been users on this very forum who have found significant holes and voids in the tails of Prentiss vises.

Manufacturing was very crude in 1900. It's just how it was.

 

[Maui]

There were some industrial manufacturers back in the late 1800s/early 1900s that produced inconsistent/poor quality products, it's true. Machinist bench vise manufacturers, for the most part, were not among them. In fact, they generally made a product of superior quality that was so over engineered it literally put some of them out of business - their products lasted so long people never had to go back and purchase another. I have vises that are well over 100 years old that are, even by today's standards, still in excellent working condition. And I use them. So lumping Prentiss in with every other manufacturing company from that era in terms of quality really is not a fair comparison.

 

[Maui]

I just finished applying the final coat of gloss black appliance expoxy to the Monarch 225. The inability to clearly make the lion head stand out well is the one downside to using black, so I've been thinking about using another color on top of the appliance expoxy to make it stand out better. And I'd like some ideas from the experts here on how best to do it. Should I just paint the lion head alone, or paint the entire rectangular panel that it appears on? Or would a nice two tone paint job be in order here? For the other color I am thinking of using Rustoleum bright gold. Here's a Franklin vise I am painting that color.

 

[1982fxr]

Fact is, none of us actually know what the deal is with cracked Prentiss slides and we never will.

I only mentioned the inappropriate cooling because I think it came from Carla.

 

[Maui]

Fact is, none of us actually know what the deal is with cracked Prentiss slides and we never will.

I only mentioned the inappropriate cooling because I think it came from Carla.

No problem in mentioning it 1982fxr. I do know the reason for my particular vise - abuse.

 

[1982fxr]

Personally, not a huge fan of gold for the lion. I don't have any better ideas though. That head is a tough one.