Mounting A Forster 3-in-1 Case Mouth Cutter on A RCBS Trim Pro

[Fire4Effect]

Has anyone incorporated a Forster 3-in-1 Case Mouth Cutter on the RCBS Trim Pro? I see the Forster 3-in-1 Case Mouth Cutter is designed for a.490" shaft diameter, but my RCBS Trim Pro shaft is 0.494” Any chance someone is offering a modified RCBS Trim Pro shaft to allow the attachment of the Forster 3-in-1 Case Mouth Cutter?

 

[mousegunner]

I've been wanting the same. I had thought of chucking the shaft and using some wet or dry to take off the .004 but there was something else that stopped me but don't remember what.

 

[cwebster]

Ream the Forster part out with a .492 Use it in a hand drill if needed.

 

[Fire4Effect]

I have never used a reamer before. I suspect the reamer would have to be larger than 0.494”. How do start the cut and keep the bore in line?

 

[RickyK]

I just finished that project . Had a friend to chuck in a lathe and take a few thousands off the shaft with sand paper and slid it on.

 

[kerjo]

RickyK and Fire4Effect, as I reloaded for more rifles, I added more RCBS plates and trim cutters and motorized my RCBS trim cutter unit. Curious as to why you chose the Lyman motor instead of the RCBS motor? The only thing different between the RCBS Trim Pro when I bought it about 10 years ago and Trim Pro 2 is the universal shell holder that I can add for about $50. But I've got all the shell holder plates that I need without getting it. I like the fact that I don't have to change my cutter adjustments when changing calibers.

 

[mousegunner]

I just finished that project . Had a friend to chuck in a lathe and take a few thousands off the shaft with sand paper and slid it on.View attachment 1302485View attachment 1302486

I'm interested in seeing more views and or plans for that sliding platform.

What rpm does that Lyman run at?

 

[Fire4Effect]

I just finished that project . Had a friend to chuck in a lathe and take a few thousands off the shaft with sand paper and slid it on.

I don’t have a lathe, but I do have a drill press with a chuck that will take a 1/2” shaft. I am guessing I only need to take off 0.003” to reduce the diameter by 0.006”. What grit sandpaper should I use? Would 220 wet sandpaper with a lubricant be a good choice?

 

[mousegunner]

I don’t have a lathe, but I do have a drill press with a chuck that will take a 1/2” shaft. I am guessing I only need to take off 0.003” to reduce the diameter by 0.006”. What grit sandpaper should I use? Would 220 wet sandpaper with a lubricant be a good choice?

I'm the same with a drill press, 220 seems too much to me, I'd try something finer, might take a little longer but you don't take off too much too fast but that's just me.

 

[cwebster]

I have never used a reamer before. I suspect the reamer would have to be larger than 0.494”. How do start the cut and keep the bore in line?

My Forster trimmer shaft is .490. That means the cutter assy has about a .492 or so dia. for clearance. A .496 reamer is going to follow the existing hole in the cutter, so no lathe needed. A hand drill or drill press will work too if you have a vise to hold the cutter. If you can get the shaft of yours in the drill chuck you can sand enough off for the new cutter to fit and would cost nothing. Yea I should have said .496 reamer originally

 

[RickyK]

RickyK and Fire4Effect, as I reloaded for more rifles, I added more RCBS plates and trim cutters and motorized my RCBS trim cutter unit. Curious as to why you chose the Lyman motor instead of the RCBS motor? Was price a factor in using the Lyman motor rather than the RCBS motor? The only thing different between the RCBS Trim Pro when I bought it about 10 years ago and Trim Pro 2 is the universal shell holder that I can add for about $50. But I've got all the shell holder plates that I need without getting it. I like the fact that I don't have to change my adjustments when changing calibers.

Already had the Lyman. !!!

 

[RickyK]

I don’t have a lathe, but I do have a drill press with a chuck that will take a 1/2” shaft. I am guessing I only need to take off 0.003” to reduce the diameter by 0.006”. What grit sandpaper should I use? Would 220 wet sandpaper with a lubricant be a good choice?

Don't use a reamer ! Chuck it up and use sand paper and it will stay concentric .

 

[RickyK]

I'm interested in seeing more views and or plans for that sliding platform.

What rpm does that Lyman run at?

Don't know the rpm's . Way faster than you need !!!

 

[cwebster]

Don't use a reamer ! Chuck it up and use sand paper and it will stay concentric .

A reamer will float itself into the existing hole and stay concentric but if he can spin up the existing cutter shaft I agree with sandpaper and alot cheaper too....

 

[Fire4Effect]

OK, I confirmed that my drill press chuck will take a 1/2” shaft. Any tips on how to keep even pressure with the sandpaper on the shaft so I don’t end up with a taper?

 

[mousegunner]

OK, I confirmed that my drill press chuck will take a 1/2” shaft. Any tips on how to keep even pressure with the sandpaper on the shaft so I don’t end up with a taper?

Flat piece of wood or a ruler but just the end where the cutter goes in, don't need to reduce the whole shaft.

 

[tac284]

PM sent with offer.

 

[209jones]

Was wondering about doing this the other nite, didn't measure shaft yet, doing the shaft makes more sense to me, as I have a Forster trimmer as well, then the cutter will fit both, and ir won't hurt anything on the RCBS unit.