Since MMC has been out of business for some time now.

Is there anyone who service the power checkering head and cable ? I don't believe Ullman does.

Craftsman, did you try the below?:

https://www.sightsinc.com/prod...wer-checkering-tool/

In the past I had trouble contacting this company. Maybe they are back in operation now. I will see if I can contact them next week. Thanks

Had one of mine rebuit about a year ago...no issues

Duane, did you use the guy in Burleson, TX ?

Sorry I missed this..Yes, I believe so..sounds right

I contacted Sights Inc in Burleson about MMC repairs last year. Months after I sent them my tool, I had to have a lawyer send a letter of demand to get my tool returned but it was rebuilt. The repair lasted for 2 panels of cutting. They now will not answer emails or calls. Never Again!

Thanks fellows for your experience on this matter. I was a little bit leery on the MMC service in Burleson even though he is withing driving distance.

It is sobering to realize that one has witnessed the introduction of a great product (the MMC checkering system) and lived long enough to see its demise. Bill

My MMC head went down last week.
The drive is out. I assume it's a worm drive.

The plan: Get it apart and make new parts for it. Made plenty of other things, to include M98 actions from scratch.

Is there anyone on this forum who has taken one apart? All the way down.

If so, procedure tips and pointers would be appreciated.

quote:

Is there anyone on this forum who has taken one apart? All the way down.

If so, procedure tips and pointers would be appreciated.

quote:

Originally posted by Craftsman:

quote:

Is there anyone on this forum who has taken one apart? All the way down.

If so, procedure tips and pointers would be appreciated.

Back together and purring like a kitten.

Hard crud and grease in the bevel gears, cleaned that up so the gears would mesh, re-seated the cross shaft and bearings, new grease on the bevel gears.

Timan, can you give us some pointers on disassembly and assembly?

I'm thinking that's all my MMC tool needs as well.

quote:

Originally posted by Timan:

quote:

Originally posted by Craftsman:

quote:

Is there anyone on this forum who has taken one apart? All the way down.

If so, procedure tips and pointers would be appreciated.

Back together and purring like a kitten.

Hard crud and grease in the bevel gears, cleaned that up so the gears would mesh, re-seated the cross shaft and bearings, new grease on the bevel gears.

Remove the LPI guide and spring.
Remove the cutter wheel, the cutter wheel is a left hand thread.
Remove the guide assy. by unscrewing the brass adjustment knob, there's a detent plunger watch for it upon removal of the guide assy.
Remove the set screw back on the handle.
Remove the set screw on the bottom of the head.
Unscrew the handle from the head. (right at the knurl).

The beveled drive gear and all is connected to the hand piece it just screws out, inspect the drive gear and clean it.
Remove the small cap screw of the left side, it's there to hold the brass bearing support in, you don't actually have to take it out but I did.
Remove the slotted hollow brass screw on the right side of the cutter shaft, there's a bearing inside this screw, the screw is hollow to hold that bearing.

The right side bearing may or may not come out with the brass screw, mine came out with the screw.
There's a small .048 diameter on the right side of the cutter shaft, use caution, don't bend or break it or you're done.
With that in mind tap or push the cutter shaft out the left side of the housing.
In retrospect, a custom hollow punch 1/16 hole it should be used to push the cutter shaft out the left side to mitigate damage to the .048 dia. on the end of the cutter shaft.

The head is stripped now and cutter shaft is out.

clean the gear, grease it and re-insert into the housing, let it go all the way in so its beyond the brass bearing support on the left side.

Roll burnish a burr on the left side brass bearing support it doesn't take much of a burr to hold the cutter shaft back against the drive gear for mesh.

Re-install the right side bearing over the .048 diameter on the cutter shaft, this can be done either with or without the hollow brass screw/bearing support.
Turn the hollow brass bearing support screw in on the left side, ensure the .048 diameter is in fact inside the bearing race and inside the hollow brass bearing support screw, some fiddling required but it does go.

Prior, inspect the .048 dia. on the right side of the cutter shaft to ensure there is not a burr on it. Mine had a burr which was part of my problem. ("right side not fully supported.")

Screw the right side hollow bearing support screw in so there's no end play in the cutter shaft but not so much as to over come the roll burnished upset on the left side brass bearing support, you can tell when it's there as it will get really hard to turn the brass bearing support on the right.

Install the drive and hand piece far enough to install the guide assy. and detent assy. for the guide, screw the rest of the way down.
Feel for mesh on the gears, wiggle it, make sure its meshing, you can feel around by turning the handle part without the top screw in 4 or so inches back, all should be connected and meshing, you can feel if it is or is not meshing.

Install the set screw on the bottom of the head.
install the set screw up on the hand piece.

Overall,
In working with this head it would seem MMC could have done better with a different king of bushing bearing support on the left side of this head, a bushing with a better shoulder on it for a better thrust bearing setup to control end play in the cutter shaft. A mod. is possible here with a better bushing design. I just went back to the roll burnished edge on the left side to hold cutter shaft in mesh with the drive.
I think what happens is the gear set gets filled with crud and the crud over comes the roll burnish on the left and it doesn't take much and it's out of mesh and won't work.

Another point of interest:
I bought my MMC off ebay 25 years ago.
When it came in, it was out of mesh and didn't work. I sent it in to MMC, they sent it back in mesh and working, however, I always though it ran rough and inconsistent, just not really right.

Part of working on this head was the discovery of a coil spring installed on the cutter shaft pushing on the right side bearing to the left side bearing, having this coil spring in there made very little sense to me as it was actually working to disengage gear mesh and trying to push the cutter shaft out the left side of the head.

I decided that coil spring on the cutter shaft was not necessary and was working against what is trying to be achieved, which is gear mesh not gear un-mesh.
With that coil spring out of there and the bearings and all properly assembled this head runs better than it ever has, super smooth, tight and normal in sound.
before it was snapping and popping doing all kind of stupid things, fought it for years, just got used to it kind of being a POS, but still made decent checkering with it
in spite of that.

Could it be that MMC was in such dire straits that they would do about anything to one of these heads to get it back out the door? I don't really know, but it would seem that way.

Looking at this tool really makes one wonder how MMC could make the thing with any margin whatsoever, even at old world dollars, still way underpriced for a very small and very obscure market.
As far as tool and time expenses go, you can always get more money as it's next to worthless anyway, it's just the necessary grease to make things go. But time, once it's gone, never to return.

Even though I have my MMC going for now I still see it as a weak link in the chain and will likely get a titan at some point but would like to know more about the titan, is it truly superior. Is it supported, or again made to cheaply and on the verge of going extinct as well. $1,500 ish really is not out of line for one of these done right.

Timan, your instructions are much appreciated. When Bill Mowrey , who manufactured Mowrey black powder rifles, retired over 30 years ago I bought his shop and equipment which included an MMC tool and Foredom drive. It had not been used much nor abused. I've used it for all these years. It is a little noisy and it surely needs cleaning and lubing. I've considered the Titan which is about $ 2400.00 now for the complete electric set up. Michael Ulman is good to deal with, very knowledgeable and as long as he is in business I would think one of his tools would be a good investment. Thanks for your help.