I frequently see references to recievers being "surface ground". I assume this means having thier irregularities ground off leaving smooth parallel surfaces. My problem if that I can't imagine how this could be accomplished on the common machine shop surface grinder. Maybe on a very large surface grinder using concave face dressed wheels, but I would think it would be a rare gunshop having a grinder that large. I would guess putting a reciever on a mandrel between centers on a small lathe and useing a tool post grinder would work if the motion of the reciever was controled by hand. So how the heck is this done?

thanks for the photo- do you finish up with filing, or is it necessary?

thanks.

Interesting set up, thanks for the photo, worth a thousand words as they say.

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Originally posted by GSP7:
http://community.webshots.com/inlinePhoto?photoId=10413...4nUqyrW_th.jpg[/URL]

Great set of photo's and comments. Thanks to the original author!.................DJ

LJ

That isn't the only way to surface grind a receiver. Brownells sells a kit that you can use in your drill press to surface grind them.

Surface grinders are made for grinding.
A drill press is for drilling. Lathe for cutting. I wouldnt put a grinding wheel in my mill either.

quote:

Originally posted by gsp:
Surface grinders are made for grinding.
A drill press is for drilling. Lathe for cutting. I wouldnt put a grinding wheel in my mill either.

The owners manual on my Southbend Drill press shows how to surface grind using a cup wheel and collar below the table. You are supposed to swing the table back and forth under the cup wheel. They put class 7 bearings in their drill presses. I'd never do this on mine cause I've got a surface grinder in the shop already. There's plenty of hand work left after surface grinding anyway. If all you had was a GOOD drill press this may be a viable alternative???? Beats a poke in the eye with a sharp stick.

I never said it couldnt be done, just that I wouldnt.
I have 10,000.00 in my lathe and mill. I keep all my grinding and sanding away from them. Keeps the ways cleaner. Although you could cover them.
More than one way to skin a cat (grin)

quote:

Originally posted by gsp:
I never said it couldnt be done, just that I wouldnt.
I have 10,000.00 in my lathe and mill. I keep all my grinding and sanding away from them. Keeps the ways cleaner. Although you could cover them.
More than one way to skin a cat (grin)

My equipment is cheaper, but my sentiment is the same.

All grinding and sawdust is outside the mill and lathe area.

I cover the equipment with old sheets. That keeps the ones in still air from rusting, but the ones that can feel the wind will rust anyway.

Surface grinding is done on a mandrell at very high RPM's. A mandrel with the action on it is on an indexing collet spin indexing head so you can rotate the action in as small as one degree increments. The surface grinder at this high speed will cut through the hard surface and size the action to a very exact dimension.

Mark Stratton's excellent book "Tricks of the Trade, Custom Rifle Metalsmithing" details how to build the fixtures. It can be done on a small surface grinder. Having done enough of them, I would not attempt nor do I feel you would get adequate results on a drill press.

I would not clean the small ridges between the flats up with a file. Gesswein adhesive backed sanding stips on an aluminum sanding block will clean up the surface quickly.

quote:

Originally posted by 22WRF:
LJ

That isn't the only way to surface grind a receiver. Brownells sells a kit that you can use in your drill press to surface grind them.

Oh yeah, you're right, just shows to the world how far a little ignorance can go.

Thank you for a very informative post. I would assume that lacking a surface grinder carefull hand work with the abrasive strips backed by a hard smooth backer could do a creditable job.

Yes.

quote:

Originally posted by Jim Kobe:

quote:

Originally posted by 22WRF:
LJ

That isn't the only way to surface grind a receiver. Brownells sells a kit that you can use in your drill press to surface grind them.

Oh yeah, you're right, just shows to the world how far a little ignorance can go.

Kobe

Your post actually shows how ignorant you are by calling my post ignorant. All I did was point out that somebody sold something in a catolog. Nothing more. If you are ignorant of what is contained in the Brownell's catolog its not my fault. But then you are ignorant of a whole lot of things arent you?

For anyone else who would like to read about the kit or see photos of it, take a look at page 52 of the special edition of Shotgun News devoted to Mausers.

LJ

By the way, generally speaking, if you surface grind you are looking at custom bases or at least customising your existing bases as well if you want them to look like they fit correctly.

LJ,

you can get rid of pits and dings that way, and get a finish suitable for bluing, but that is not all that is accomplished by surface grinding. I think first off if you aren't very very good with hand polishing using abrasives you are going to have a heck of a time getting all surfaces true/flat/symmetrical.

surface grinding is used not just to clean up, but you also can get the outside of the action, especially the ring and bridge areas, as concentric to the bore of the action as possible.

I would go the abrasives and hand work route if just doing minor cleanup or in the higher grits to get a finish for bluing, but wouldn't use it for major removal, just my personal choice. If I wanted any more than that I would send to Stratton or somebody setup for it and pay them to do it.

Red

quote:

surface grinding is used not just to clean up, but you also can get the outside of the action, especially the ring and bridge areas, as concentric to the bore of the action as possible.

does the surface still need hand finishing after that?

HEE HEE, it worked.

The action only needs hand-finishing after surface grinding if you want it to look good. I turn the action 1-degree between passes which leaves very, very small flats. I then use polishing stones and abrasive cloth to smooth those out.

quote:

Originally posted by Jim Kobe:
HEE HEE, it worked.

Don't complain the next time you post and I do the same thing to you.

quote:

The action only needs hand-finishing after surface grinding if you want it to look good. Smiler I turn the action 1-degree between passes which leaves very, very small flats. I then use polishing stones and abrasive cloth to smooth those out.

what do you figure is lost tolerance-wise by the hand finish? enough, if one was to go about it a bit cruder than your method, to make a big diffrenece in quality?

I'm thinking of giving the drillpress method a shot is why I ask.

I'm speaking of practical terms here- I don't mean tolerances, etc, as found in a 5,000 dollar rifle.

I would use a mill before a drill press. You need a smooth motion to get best results.
If the grind wheel is in a drill press, the wheel only moves up and down, not left to right or front to back. Plus most press's have no quill lock to keep the same height. So you would be running the action under the grind wheel by hand, flat on the table with much friction or jump.

quote:

I would use a mill before a drill press. You need a smooth motion to get best results.
If the grind wheel is in a drill press, the wheel only moves up and down, not left to right or front to back. Plus most press's have no quill lock to keep the same height. So you would be running the action under the grind wheel by hand, flat on the table with much friction or jump.

I have a cross slide vise I could mount the whole shebang in, think it would make a difference?

IIRC when I watched a guy do it many years ago the first thing he did was put the receiver in his lathe and he took the absolute lightest cut he could on the front of the ring until he got to the recoil lug. He then worked off of that perfect circle to do he rest of his grinding.

While he had the receiver in the lathe he also made sure that the very front of the receiver ring was square or parrellel or whatever you call it.

This drill press thing sounds like the proverbial garage mechanic thing. It is too slow for a grinding wheel first off and secondly, I think it was intended for use in taking off the ears on an enfield. You just can't argue against using a surface grinder with the right setup.

Kobe

I am not arguing with you, and I agree with what you say. If a guy is doing a lot of mausers or other actions, professionally or otherwise,then certainly a good quality surface grinder is the way to go.

However, for the guy that wants to try his hand at it for whatever reason on a one or two time basis, it appears that the drill press kit from Brownells is a viable alternative.

quote:

Originally posted by 22WRF:
However, for the guy that wants to try his hand at it for whatever reason on a one or two time basis, it appears that the drill press kit from Brownells is a viable alternative.

I'm sure a drillpress would work, but a 10" mill bastard may be a better option.