How do you level a bent side plate? This plate, outside up, has a "rock" of about 1/16".

Model 31 3".

Im thinking a picture of this will assist with repair ideas

I will take a couple of pictures. While I take them, please read the following. Senior moment. I posted this in the main S&W forum.
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I have in front of me a good condition M31. When I first saw the revolver, the crane retention screw was loose. The revolver functioned OK, albeit the normal very stiff trigger.

After removing the side plate, I polishied most surfaces lightly. Rinsed everything in a cleaner and compressed air blow dryed. Reduced power springs were installed. Functioned very well. Small dabs of TW125 in appropriate places.

Installed the side plate and discovered the trigger would function until it almost reset. The lightest of touch would reset the trigger. I examined all parts, removed all parts, fully flushed revolver and parts, and re-assembled. Same problem. Started to dis-ssemble the revolver and happened to lay the side plate on flat box. The plate is slightly bowed. With the outside up, you can lightly rock the plate. I did not try to straighten. I have very fine files so dressed some of the side, not touching the "races" for the pins.

Take the plate off, it will cycle. Remove the transfer bar, replace the plate, and the glitch goes away.

The loose screw, apparently, camoflauged the bent plate.

Past all that, I am puzzled that the transfer bar causes the glitch when the side plate is on.

I did take a .001 or so off the back/side of the transfer bar with no luck.

I am sure I can put the factory trigger reset spring back and the revolver will function. However; the idea it is still "catching" on somethimg bugs me.

You may need to enlarge or use a magnifying glass. The front screw only is in and snug. Other two are not in.



I can lay the side plate on a plate of glass and it rocks. I would guess someone pried it off.

Sounds like the rebound spring has been messed with or replaced with an aftermarket. The fact is that J frames have heavy triggers. Not much you can do and keep the gun 100%. Polishing "most surfaces" leaves much to the imagination... I have seen many side plates that are not completely flat and never caused an issue. I would suggest making everything tight with proper springs and see how it functions. Could be a high pin on hammer or trigger and that will cause a semi circle mark on the inside of the plate.

Ken158, There are reduced power springs, both main/hammer and rebound slide/block in the revolver now.
I have a M60, a M10 (chambered for 357), a couple of M19s, and some Smith semis. And a lotmore.
The M60 has been set up for PCCA competition and runs like a champ. With clipped springs, the 60 ignites Federal primers all day.
When I opened the 31, it did not occur to me that the loose front screw hid the bent plate. After polishing, deburring, and working the springs, I applied TW125. One of the best lubes around for my money. Before I put the plate on, everything cycled great. Placed the side plate on, screwed everything down, but the reset glitch showed up. Through some trial and error, it was obviously the hammer pin block. Take it out, tighten down the plate and it runs fine.
Then I discovered the bent plate.

There are no (nor was) circular wear rings. The rebound block was sanded with 1000 grit on a glass plate. Sides and bottom. Lightly. Fits great.
As I stated, a new rebound spring is coming but the plate is still bent and unless I straighten the plate, I will not know what is catching. Seems halfway to replace the spring without straightening the plate.
At this time, the cycling is super and will ignite factory rounds. Without the hammer pin block.

Red Cent: I have a 'parts kit' for a three screw J-Frame that includes a sideplate that is flat. Make me an offer for just the sideplate or the whole kit that includes everything except the grips and the cylinder assembly. ............ Big Cholla

http://i289.photobucket.com/albums/l...DSC_0005-1.jpg

IMO you've found the problem, if you tighten down the sideplate it's binding up the hammer block.

The solution will require a very careful trial and error approach. One factor that you'll have to cope with is that the steel will have a tendancy to "spring back". I would approach correcting this using a small Arbor Press, they are available from Harbor Freight and pretty low prices.

Step one would be to try and "map" the present surface and find out where and how it's bent. If it was pried off, most likely it has a bit of a diagonal "crease" in it. Take a block of hardwood such as Oak or Maple and shape to an anvil that you can use to exert even pressure across that "crease". Then lay that sideplate of a piece of the softest pine you can find on top of a plate of 1/2 inch to thicker steel. Put this in the saddle of the arbor press and use that hardwood anvil to apply pressure. The goal is to slowly exert more force in repeated stages until you find the force that will just take that bend out of the "crease". Once that's done, put it on your glass plate and map the high spots again. With enough repeated trials you should be able to get that sideplate straight enough to restore function, if you have a very good "eye" you may even be able to get it near perfect. Just be aware that it's going to take patience and you'll have to resist the urge to rush it.

Now one tip concerning using an Arbor Press. Watch the position of the handle and use that position as a reference for the force applied. Quite simply, apply a load, look where the handle is and if a bit more force is needed, turn that handle a smidge further. You'll find the coft pine does compress and take a bit more turn as it does but with practice and time you'll get a feel for the effect of the compression of your support versus the work you are actually doing to the sideplate.

Big Cholla, I will definitely keep the offer in mind.

Scooter123, thanks for the detailed instructions. I will give this a try. Sounds more intelligent than my three pieces of wood.

Scooter123.
I used a vise to play arbor press. The plate is as flat as it gets. It did relieve the action some but just a tad of touch remains. I dropped a #7 lead shot in first, replaced the rebound spring and it runs very well, thank you.