03-14-2015, 01:34 PM
I've got a fair number of hammers myself, but most like the 2nd one from the right. I won't ever see ones like mine for sale...my grandfather made them!
Got this in today's post/mail, another eBay find that I wasn't particularly looking for:
![[Image: IMG_20150314_140622713_HDR_zpsqklqiyws.jpg]](http://img.photobucket.com/albums/v466/kenm10759/Dads%20shop/IMG_20150314_140622713_HDR_zpsqklqiyws.jpg)
It's the SIR 0750 P22 shown in the catalog just above the tool itself. Among the internal threading bars, this is the smallest diameter (Ø 3/4") one that accepts the larger 22IR size inserts. When I was making the 1-1/4-5ACME threads for Darren's machine, the elevation screw and nut set, this would have been nice to have. The smallest bore it can get into is Ø 0.900", the bore on the 1-1/4-5ACME thread is Ø 1.050".
Coincidentally it came with two inserts, both 22IR-5ACME, which is the exact insert I would have used for the that internal thread on his part! One edge of one insert has had more relief angle ground on its leading edge, which forces me to think whoever used it was trying to thread a higher helix angle thread than what it was designed to do.
$70.00 shipped for the bar and two inserts. The reason I used HSS for Darren's project at that time is because the bar new would have been over $150 and inserts over $30 each. This setup probably wouldn't have chattered on the last "spring pass" as my flat-topped HSS tool and steel bar did. Oh well, ready for the next one!
Got this in today's post/mail, another eBay find that I wasn't particularly looking for:
It's the SIR 0750 P22 shown in the catalog just above the tool itself. Among the internal threading bars, this is the smallest diameter (Ø 3/4") one that accepts the larger 22IR size inserts. When I was making the 1-1/4-5ACME threads for Darren's machine, the elevation screw and nut set, this would have been nice to have. The smallest bore it can get into is Ø 0.900", the bore on the 1-1/4-5ACME thread is Ø 1.050".
Coincidentally it came with two inserts, both 22IR-5ACME, which is the exact insert I would have used for the that internal thread on his part! One edge of one insert has had more relief angle ground on its leading edge, which forces me to think whoever used it was trying to thread a higher helix angle thread than what it was designed to do.
$70.00 shipped for the bar and two inserts. The reason I used HSS for Darren's project at that time is because the bar new would have been over $150 and inserts over $30 each. This setup probably wouldn't have chattered on the last "spring pass" as my flat-topped HSS tool and steel bar did. Oh well, ready for the next one!