Making reamers?

[deltaenterprizes]

That is better quality bearings than a Dremel! I may have to give it a try.

[trevj]

The bearings in a Dremel tool are not suitable for close tolerance work.

Home made radius tools in general, are not suitable either. So that's kind of not really much of a point.
If a fella is making his own radius tool, he's gonna have to live with a few gaps in the capability, ain't he.
Otherwise, he'd just buy the tool and get down to making money with it.

We're not talking about guys making rocket parts for NASA, either.

Cheap gets cheap, but cheap can be made to work if the nut holding the handles has the capability to recognize cause and effect, while working.

But I'd be willing to wager that the average fella making a radius tool along the lines of the one with the Rotozip on it, will have more play in his pivot, than there is play in the Dremel's bearings.

Cheers
Trev

[scrapcan]

teddyblu,

thanks for sharing once again. You have lots of good info to pass along on swaging and die making. I for one thank you for everything you share.

[teddyblu]

TREV.
You could be right on the pivot precision, my mike and finished product tells me if it is a usable product.

Please show us what you do ?

Teddyblu

[deltaenterprizes]

The reason I prefer the Rotozip over the Dremel is a more rigid housing and a more powerful motor.
I made a bracket to mount a HF air grinder to my lathe tool post to do a small job, not precision, the bearings are mounted in plastic, but it did the job.

[teddyblu]

The rotorzip can run to 30000 rpm, so the wheel should be rated for your max rpm and well dressed and balanced. This wheel Is 1.5 dia or close to it.

They mabe some vibration but repeatable ojive and better than a file,emory cloth and eyeballing the ojive.

[MarkP]

Older method used in bullet industry to make dies: 1. Transfer 10X hand drawing of bullet profile to template (plastic or aluminum) 2. Use 1:10 pantograph to make 1X steel template. 3. Use steel template in lathe with tracer attachment. 4. Cut EDM electrodes with bullet profile. 5. Die sink EDM swage die. (die mat'l usually carbide 94% WC , 6 % Co)
The next progression the 1:10X pantograph was replaced by using a wire EDM to generate the tracer templates from a CAD file of the bullet.
The electrodes were then made with a CNC lathe rather than on the tracer lathe directely from a CAD file.

[Reload3006]

Older method used in bullet industry to make dies: 1. Transfer 10X hand drawing of bullet profile to template (plastic or aluminum) 2. Use 1:10 pantograph to make 1X steel template. 3. Use steel template in lathe with tracer attachment. 4. Cut EDM electrodes with bullet profile. 5. Die sink EDM swage die. (die mat'l usually carbide 94% WC , 6 % Co)
The next progression the 1:10X pantograph was replaced by using a wire EDM to generate the tracer templates from a CAD file of the bullet.
The electrodes were then made with a CNC lathe rather than on the tracer lathe directely from a CAD file.

That is the way we do it today. But they were making bullets long before there was a computer. If you have a lathe and are short on funds hand grind a form tool and you can get very close that way then sand and file to finish. IF your making a reamer to make a swage point form die. That reamer will make several dies unless you break it. Cut out a template and use it to hand grind your form cutting bit. It really does work.