How to make a cut in this roller?

[jimbo84]

I have a rolling mill with various rolls. There is one with U shapes in it but the largest U isn’t big enough.

I have a flat roller that I could potentially cut the right shape in.

Question is how would I go about it because I’m guessing it is hardened to some degree?

Is it doable on my lathe or is it something only a machine shop with a grinder could do?

Existing roller


Flat roller that could be machined

 

[Maker]

Hardened steel turns just fine with carbide tooling and a suitably stout lathe - A Harrison will do it but I wouldn't expect much from a Drummond for example.

 

[gaz1]

do you mean the tube roller ?

 

[Erie Fred]

The rolls at work for rolling copper are very hardened D-2......

 

[jimbo84]

I’ve just had a look on the supplier’s website and it says they’re EN31 hardened to 50-55HRC.

They are a reputable supplier (cooksongold) but it is made in china so could well be chinese hardness and not quite the same as anyone else’s hardness.

 

[jimbo84]

Hardened steel turns just fine with carbide tooling and a suitably stout lathe - A Harrison will do it but I wouldn't expect much from a Drummond for example.

I have a bench mounted Boxford CSB so doubt it’s up to the job by the sounds of it.

 

[6ply]

How about make a tool post mount for an angle grinder? Then grind the channel under power. It would certainly cut a groove, but I'm not sure whether it would meet your needs for required profile.

Or...

Do you have access to a surface grinder? I've used a spin indexer to grind a roller before. It's easy enough to profile the grinding wheel to the correct profile.

 

[Maker]

I have a bench mounted Boxford CSB so doubt it’s up to the job by the sounds of it.

It might manage. Worst case, it leaves a crap finish and you're back to figuring out a grinding solution.

 

[E T]

I have a bench mounted Boxford CSB so doubt it’s up to the job by the sounds of it.

Every time I'm amazed at what my little South Bend 9A is capable of in hard stuff.
Your Boxford should do as well I guess.
I have several old LandRover halfshafts which are something like EN19 I believe.
Don't know what the hardness is of the outside layer, but the South Bend has no problems with it. Even leaves a bloody nice finish.

 

[MattF]

How big is the roller, & what size groove are you wanting to cut/grind in it?

 

[masleeve]

Following this one with interest as my Mrs has the same rolling mill .

 

[jimbo84]

How big is the roller, & what size groove are you wanting to cut/grind in it?

And this is what I’d ideally like to cut into it. A half round groove 6mm wide and 2mm deep.

 

[jimbo84]

How about make a tool post mount for an angle grinder? Then grind the channel under power. It would certainly cut a groove, but I'm not sure whether it would meet your needs for required profile.

Or...

Do you have access to a surface grinder? I've used a spin indexer to grind a roller before. It's easy enough to profile the grinding wheel to the correct profile.

No I’ve no access to a surface grinder. Just a mill and a bench lathe.

 

[Beanwood]

Wow - it wouldn't even have ocurred to me that I might NOT be able to do that job on my old Boxford. I still have a lot to learn.

 

[Erie Fred]

View attachment 476752

View attachment 476753

And this is what I’d ideally like to cut into it. A half round groove 6mm wide and 2mm deep.
View attachment 476754

I see that half round wanting to chatter.

 

[E T]

I see that half round wanting to chatter.

Yes, making that cut with a form tool or button insert in one go in 55HRC on the Boxford will be a problem.
I would rough most of ik out with a DCMT insert and then the finishing with a 4mm button insert.
Small bites. Get in, get out before the chatter can start.

 

[Seadog]

It may chatter, but I've parted off toughened steel on my AUD with few problems, using both 2mm and 3mm inserts. As suggested, make a groove undersize and finish to shape to reduce chatter.

 

[MattF]

Popping a groove in with a parting tool first will help on the chatter front. Less for the tool to remove.

 

[Agroshield]

It probably goes without saying that the right hand end of your drawing should be the chucked end and the left hand end supported by the tailstock centre. You could also add the fixed steady.

Technically, it is not going to be half round if it is 6mm wide and 2mm deep. If the groove is 3mm radius and 2mm deep, it would be 5.66mm wide.

 

[jimbo84]

Thanks all. I’ll mull it over. I may end up just buying some ready rolled wire, rather than try to cut this out, I’d need to buy some tooling (good excuse) and there’s still no guarantee of me being able to do it.

The idea was to melt down some silver (to start with) and roll into a couple of rings then try it with gold.

Given some other issues along the way with other aspects of getting it to the rolling stage I may just go for the ready rolled wire.