Mainspring Vise

[seaguy]

Might just be that the gun makers had another pricey gadget to sell as a “had to have” item since there were no visegrips for sale back then Hey? Seems like I read once that the turn screw vise was used just to keep some compression on an “ in use “ spring while removed from the lock. Old springs could begin to develop micro cracks at the bend when left fully relaxed since they normally have some compression on them at all times while installed. So..It might also make your spring last longer. Makes sense to me but hey...I’m just an old retired maintence guy so what could I know?

 

[Rifleman1776]

springs could begin to develop micro cracks at the bend when left fully relaxed

I don't know anything about springs except there are more myths about them than WD-40. Frankly, that statement just strikes me as illogical.

 

[M. De Land]

I don't know anything about springs except there are more myths about them than WD-40. Frankly, that statement just strikes me as illogical.

The highest stress point in a V spring and where most of the breaks occur (turn back), gets bent less and thus stressed less when being compressed with the vice grips, which make contact farther away from the turn back on the lower leaf. The VG's allow more of the lower leaf to flex than does the vice and the contact points are padded with leather which removes any stress riser.
Also the VG's are adjustable and lock so the spring is flexed no more than is necessary for removal, just as the vice is with it's screw jack.

 

[M. De Land]

Might just be that the gun makers had another pricey gadget to sell as a “had to have” item since there were no visegrips for sale back then Hey? Seems like I read once that the turn screw vise was used just to keep some compression on an “ in use “ spring while removed from the lock. Old springs could begin to develop micro cracks at the bend when left fully relaxed since they normally have some compression on them at all times while installed. So..It might also make your spring last longer. Makes sense to me but hey...I’m just an old retired maintence guy so what could I know?

In my opinion most spring breakage has several main causes , poor spring stock, poor dress out (before and after forming and heat treating) , improper heat treating and poor installation.
The turn back needs to have all the corners dressed smooth and radius-ed before and after heat treating, along with any cross leaf file marks or scratches removed. It is common for small cracks to occur in the turn back when heat forged. It helps to radius and smooth all four corners in this area before and after forming and heat treating.
The turn back is the one place where cast springs may have an advantage in that they are not pre-stressed from the bending forge but as a general rule I prefer "spring stock" springs.
One other point in spring making is that micro cracks can occur on the inside bend of a turn back as well as out side bend and is the reason to have those corners radius-ed and smoothed as well.

 

[Rifleman1776]

I don't know anything about springs except there are more myths about them than WD-40. Frankly, that statement just strikes me as illogical.

Sorry guys, I'm still bumfuzzled as to how a relaxed spring can break from not being stressed. I'll back out of this discussion as I have no knowledge on the subject to contribute.

 

[M. De Land]

Sorry guys, I'm still bumfuzzled as to how a relaxed spring can break from not being stressed. I'll back out of this discussion as I have no knowledge on the subject to contribute.

I appreciated your discussion and it is an interesting subject to which there is always something new to be gained and learned by chewing on it with other interested parties. I always like to say that no one knows everything about anything but God himself.

 

[PluggedNickel]

Mine is an antique, it used to belong to my great uncle. He was a tool and die maker in Columbus, Ohio prior to WWI. Edie Rickenbacker was his apprentice prior to the war. I've got a lot of tooled steel hammers and other tools he made. Antiques all, and still working and going strong! I polished the feet on it and radius-ed the edges, but I still use a piece of .003" brass shim between the main spring and the vise to keep from scratching my polish jobs on the springs.

 

[WRustyLane]

Where might I obtain a thumb screw for the mainspring vise? I seem to have broken the thumb screw using a pair of pliers on it. I found a screw to replace it but it has a phillips head and it's not PC/HC.

 

[Grenadier1758]

You should be able to find a thumbscrew at a local hardware store that has those drawers of screws and bolts. Take the old bolt to the store with you. I prefer ACE Hardware as they seem to have a larger selection.

 

[WRustyLane]

Thanks. I think there's an Ace Hardware just across from the Kroger my wife visits. I shall take my screw and perhaps my vise with me and I shall inquire within.

 

[Tanglefoot]

If your local ACE can't help you, Amazon has thumbscrews also. I don't know how you'd go about making sure you were getting the correct thread size and diameter though. I believe Dixie Gun Works has them, but my catalog wandered off with somebody and hasn't come home yet. I know they have mainspring vises, for sure.