Ultra Precision 1/2” keyless chuck R8 shank

This chuck is brand new and has never been used and has not been inserted into a machine. I am selling it because I ended up not getting a milling machine with an R8 spindle. I chose this chuck because the R8 taper is an integral part of the chuck and because the runout is the lowest available from any manufacturer. This is not a sales pitch. Look at Jacobs, Albrecht, Accupro, Sowa, Glacern, Maritool. The runout on those chuck will be 0.002 to 0.004. That would be actual runout that you would measure in your shop. They can report what they want, but with precision ground stock that is what you will get. I researched extensively before purchasing this chuck and bought it because it has the lowest reported as well as actual runout. I would buy another from them if they had keyless chucks for a CAT40 taper.

*Exceptionally HIGH QUALITY, built to perform
*0-1/2″ Capacity
*Ultra High Precision, Maximum of +/-.00078″ Runout!
*R-8 Shank to fit most Bridgeport style milling machines
*One Piece Shank, no tapers to come apart
*Includes Spanner Wrench
*Knurled Grip for easier operation by hand
*Comes in original box

This will be delivered to you in the original box, padded with packing material and in a another larger box to ensure that you receive the chuck in perfect condition.

Price is $120 shipped.

$120 is exactly the internet price, and your ad text and photographs are right out of their online ad:

https://www.precisionmatthews.com/shop/0-12-ultra-high-precision-keyless-drill-chuck/

That makes me wonder about your "This is not a sales pitch." Are you in fact just a home shop guy who wants to get 100% of his money back after buying the wrong chuck?

Also, I was curious as to where this chuck was made. Precision Matthews, with a sales operation in Pennsylvania, says "Please check each item for country of origin, it varies." Checking their website for country of origin of this particular chuck provides no indication of country of origin. For some of us that still matters.

-Marty-

These are made in Taiwan, according to the "item specifics" see here:
BRAND NEW 1/32" - 1/2" ULTRA HIGH PRECISION KEYLESS DRILL CHUCK R8 R-8 SHANK | eBay

Marty Feldman said:

$120 is exactly the internet price, and your ad text and photographs are right out of their online ad:

https://www.precisionmatthews.com/shop/0-12-ultra-high-precision-keyless-drill-chuck/

That makes me wonder about your "This is not a sales pitch." Are you in fact just a home shop guy who wants to get 100% of his money back after buying the wrong chuck?

Also, I was curious as to where this chuck was made. Precision Matthews, with a sales operation in Pennsylvania, says "Please check each item for country of origin, it varies." Checking their website for country of origin of this particular chuck provides no indication of country of origin. For some of us that still matters.

-Marty-

Click to expand...

Marty. These chucks are made by Vertex. I can take other photos but they will be the same.

A few other photos.

This is a professional machining forum.

The lowest runouts on commodity machining stuff are things like heat shrink stuff from kennametal etc.,
hydraulic grips from various,
regofix holders from switzerland, or say schaublin,
maybe big kaiser and similar,
maybe 2-contact mounts from various.

ALL above would typically deliver about 2 microns or 0.002 mm, maybe 5" == 120 mm OUT from the spindle nose.
(When using a test bar or perfect tool).

Accuracy is length cubed, and 120 mm out at 0.002 mm is about 40-80-200x better than 0.02-0.04 mm at chuck.

More or less every basic entry level modern machine tool has 0.002 mm TIR at spindle nose,
and more or less every premium tool/chuck/grip is around 0.002 mm or better out the spindle by some distance.

Multiple brands demonstrate CUTs with interpolated cuts with endmills to 0.0007 mm or 0.7 microns, at workpiece.
GMC - DCG for one, US Moore Nanotech for another.
This is about 500x better.

Your chuck is fine, so is the price, but it is vastly less than "best" or "good" for modern machinists using modern tools.
Imo.

Maybe 80-90%+ of the people on this site could/would easily surpass 2 microns in TIR on a solid-carbide tool by fiddling the ends at need, to make very accurate fidgits on something worthwhile.
And charge accordingly.

Chuck is sold.