What Did You Buy Today?

GreatOldOne said:
eBay listing pics, as I literally just pounced on this. 5 1/4” six jaw set true chuck. Listing just said ‘English, precision’ and looking at other similar vintage chucks I believe it’s a Pratt - Burnerd. Which if it is I just stole it. :cool:
Ill have to make a back plate but that’s no big deal… but ya, new chuck. And lesser yay - cast iron dust everywhere again. :)
Click to expand...

Nice buy.

I don't see the set true features that I expected (4 setscrews to bear on the pilot diameter). Please clarify what makes it other than a plain back chuck.

Also, I'm curious about the 3 socket head fasteners counterbored into the OD. What do those do? Teach me something. :)
 
As far as I’m aware it these allen / cap heads that shift the chuck about the axis of rotation to dial it in. I will be checking out how it all works when it arrives… it’ll be a voyage of discovery! 25E7DE39-7B95-4C37-ACDB-7C3089BDE4C6.jpegBDF078D8-34AC-4222-BA57-5178464B06C9.jpeg73124366-9278-4E55-AB9B-EEBB77B2C8E8.jpeg
 
@GreatOldOne

Thanks so much for the detail. I didn't read it 100% but read enough to get the gist of it.

It looks like the 3 socket head screws bear on, and adjust the eccentricity of, the 3 lobed piece in the center of the chuck. I assume that piece locates the scroll and, therefore, the jaws. There must be more to it, I think, but I'll be able to sleep tonight.

One of the shortcomings of scroll chucks is that the scroll gets worn more where it's used more, so different diameter workpieces runout different amounts. Your chuck will let you easily reset concentricity at any workpiece diameter. Very neat and thank you for posting.
 
My Halo light came, I think it gives out a pretty good amount of light, it is brighter than my previous one. My Quasar goose neck LED is still brighter, but you have to deal with glare, and shadows. 126 LEDs if you started counting.


 
I think this qualifies as a tool. 83" x 55"x13", about 7200 lbs of granite surface plate. It's actually the base from a former CMM.

IMG_4152.JPG
I really need to sell this trailer to stop myself from picking up these large random finds ;)
 
You must log in or register to reply here.
Back
Top