Machining A New Back Plate

[kd4gij]

Mine is metric also picked some up at the local hardwear store.

 

[george wilson]

Cast iron is very hard on HSS tooling. Use very low RPM's when cutting it,even with carbide. To boot,imported back plate blanks can have crud in the iron that can be very bad on tooling. Hard spots,sand,etc.. If the cast iron wasn't poured correctly,it can have very hard spots.

 

[Smithdoor]

See upload for detail on back plate

Dave

 

[Jimsehr]

I don't think its that important to have a near press fit on a 4 jaw chuck. If it was a 3 jaw I would want it as close as possible.
jimsehr

 

[Smithdoor]

You need a press fit on any chuck or could move as you machine

Dave

 

[T Bredehoft]

You need a press fit on any chuck or could move as you machine

Dave

Thanks, Dave, for that. I wasn't sure.

 

[Smithdoor]

If look close at photo you will a 7 1/2
This from a weight set my son left me to use
I found a good use for weight set and low cost

Good luck
Dave

 

[Kroll]

A little information goes along ways,OMGoodness what a difference.Guys I slowed down the rpms and what a difference,wish I would have ask first before I burned up two new tips.But that will help me remember next time.Thanks so much for the help,heading in to work now had to let you guys know

 

[kingmt01]

If it screams back it down. Good rule of thumb.

 

[emasbury]

Good morning guys,well I thought that while I'm home along I would start on machining my back plate for my 4 jaw chuck to fit my Sears/Atlas lathe.Long story short,I have never really use my lathe other than just playing around so I don't know what I'm doing.I started with turning the OD for the resists that will fit inside the chuck and thats as far as I can go cause I done burned up two of my Arthur Warner tips.Guys me not knowing, but I think the back plate is made out of iron not steel cause of the chips.Anyway I am taking small cuts to work my way to the point of facing the back plate that the chuck will seat on.Guys I have my lathe set at 625 and hand feeding the HSS cutter slowly.Giving the poor information here,can someone see what I'm doing wrong,maybe this is a job for carbide instead of HSS.But I thought taking small passes and slow hand feed all would be good.I was wrong,thanks for suggestions----kroll

Here is a good video by Mr. Pete, it shows about all you need to know.