Couple of questions. Your thoughts would be appreciated.

[Tomc938]

I have a cheap shell mill with brazed carbide inserts. The inserts look like they really haven't even been sharpened.

I"m wondering if it would be worthwhile trying to grind HSS inserts (I'm not great at it) so it would at least be serviceable. I have end mills and fly cutters, so not sure if I really even need it.

Also, I picked up a 6" three jaw chuck. Looks kind of light weight, but was thinking to mount on my rotary table. There is a stub on the back that sticks out with a hole threaded, as best as I can measure 11/16 - 16.

I'm wondering 1) Is this chuck substantial enough for small jobs on the rotary table? and 2) What would be the best way to mount the chuck on the table?

Thanks!

 

[Dabbler]

Your chuck looks good. You could get fancy and make a new back plate for it, with registration built in so it is always centred.... (evil grin here)

If your table is big enough you could even use outrigger hold downs by allowing for them in the backplate design..

 

[Susquatch]

I have a cheap shell mill with brazed carbide inserts. The inserts look like they really haven't even been sharpened.

I bet it wasn't cheap back when it was first sold.....

I have two like that. I have not used them either. I didn't have an arbour that fit them. It seemed way easier to just buy a new face mill with inserts.

If you have an arbour, why not try sharpen the existing carbide with cbn or diamond? Use a jig to get them all the same and then mount them in the head installed on your mill to get them even.

I'll be interested to see how it goes.

 

[Tomc938]

Your chuck looks good. You could get fancy and make a new back plate for it, with registration built in so it is always centred.... (evil grin here)

If your table is big enough you could even use outrigger hold downs by allowing for them in the backplate design..

Thanks! I was wondering about the chuck. It weighs as much as the 5" chucks for my Craftex, but seems not as heavily made. But I figured for $30 it was worth a try.

I'm thinking of turning the "stub" on the chuck just below the level of the backing plate and mounting another backing plate with a pin to centre the chuck on the table. It's a 10" table, so there is definitely the room for clamps on the out-side.

 

[Tomc938]

I bet it wasn't cheap back when it was first sold.....

I have two like that. I have not used them either. I didn't have an arbour that fit them. It seemed way easier to just buy a new face mill with inserts.

If you have an arbour, why not try sharpen the existing carbide with cbn or diamond? Use a jig to get them all the same and then mount them in the head installed on your mill to get them even.

I'll be interested to see how it goes.

I guess I shouldn't judge the whole shell mill based on my thoughts on the insert quality. Maybe you CAN make a purse out of a pigs ear. ;o)

I don't have access to diamonds, but I never thought about CBN.

I will check into ordering one for one of my belt sanders and keep you posted.

 

[Tomc938]

So the price of CBN sanding belts made my heart skip a beat.

Diamond abrasive wheels for lapidary work are a little more affordable.

What grit would people recommend for sharpening/touching up brazed carbide cutters?

I have a couple for my lathe as well, so I could justify the cost of one to try anyway.

 

[YYCHM]

Have you tried the shell mill as is?

 

[Susquatch]

What grit would people recommend for sharpening/touching up brazed carbide cutters?

You are not gunna shape it, just sharpen it. I'd go for 6 or 800.

 

[Tomc938]

Have you tried the shell mill as is?

I tried it, but just popped it into the mill and tried it just as I got it. Cutters might not have been lined up properly.

In the chunk of aluminum I ran it over, it was quite a mess. There is no edge on the cutters, but a nice radius.