12-10-2013, 07:17 PM
12-10-2013, 07:41 PM
Hawk, I was a bit curious about the circular "spacer" between the cross slide and the compound. could it be modified or changed in order to lower your compound enough to accommodate a proper sized (for the lathe) QCTP?
Of course that strange, yet seemingly very robust, expanding toolpost anchor would have to be eliminated.
Maybe you could make a new compound to accommodate a QCTP?
Or maybe I could just shut up.
Of course that strange, yet seemingly very robust, expanding toolpost anchor would have to be eliminated.
Maybe you could make a new compound to accommodate a QCTP?
Or maybe I could just shut up.
12-10-2013, 11:12 PM
Steve, that 'spacer' is actually part of the top half of the crossfeed casting. They really didn't use any extra parts. It seems to be one very solid machine.
As a collector of classic motorcycles, I have a strong aversion to modifying original equipment. If I wanted to make a QCTP, I think I would make a new top slide for the compound. It comes off quite easily, so changing back and forth would be a snap.
The carriage screws both have 3mm pitch. Lead screw, on the other hand, is 4 tpi.
As a collector of classic motorcycles, I have a strong aversion to modifying original equipment. If I wanted to make a QCTP, I think I would make a new top slide for the compound. It comes off quite easily, so changing back and forth would be a snap.
The carriage screws both have 3mm pitch. Lead screw, on the other hand, is 4 tpi.
12-25-2013, 12:58 AM
A couple of weeks ago, I made a replacement handle for the back gears, with the intention of prettying it up when I got the chance. I used the ball turner on the Hercus lathe to turn the ball on the end, then transferred to the big lathe to turn the taper. I set the compound to 2* and used the new tangential toolholder to cut most of the taper.
[attachment=7489]
The finished taper.
[attachment=7490]
Before.
[attachment=7491]
After.
[attachment=7492]
[attachment=7489]
The finished taper.
[attachment=7490]
Before.
[attachment=7491]
After.
[attachment=7492]
12-27-2013, 12:04 PM
I sent Tony Griffiths an email last night with a write-up and a few pictures. This morning, he already had it added to his site.
http://www.lathes.co.uk/ornmaskiner/page2.html
I burned over 40 photos to a disk this morning to mail to him. I may not get any additional information about this lathe, but at least I can add to what's available.
In the info he has on the 185-GK, it shows a massive QCTP, which would appear to fit on the same style of compound. I may have to make one of those.
http://www.lathes.co.uk/ornmaskiner/page2.html
I burned over 40 photos to a disk this morning to mail to him. I may not get any additional information about this lathe, but at least I can add to what's available.
In the info he has on the 185-GK, it shows a massive QCTP, which would appear to fit on the same style of compound. I may have to make one of those.
12-27-2013, 10:03 PM
Breakthrough! I was researching using various change gears to convert to metric, hoping I could reverse the process with gears I have to cut standard threads. I went down to look at the QCGB charts again and it occurred to me that the lower chart actually referred to standard threads.
[attachment=7514]
The headings that mention the 40- and 45-tooth gears have the same wording as the ones in the top chart (that covers metric threads) for the first and last gears. After I changed the 80-tooth to 40 and the 127 to 45, every test I ran produced the thread shown on the chart.
[attachment=7515]
It can cut 32 standard threads, from 3 to 44 tpi, some with half-values, like 9 1/2 tpi.
[attachment=7514]
The headings that mention the 40- and 45-tooth gears have the same wording as the ones in the top chart (that covers metric threads) for the first and last gears. After I changed the 80-tooth to 40 and the 127 to 45, every test I ran produced the thread shown on the chart.
[attachment=7515]
It can cut 32 standard threads, from 3 to 44 tpi, some with half-values, like 9 1/2 tpi.
12-28-2013, 05:55 AM
That's great you got the thread cutting capabilities sorted out and very cool your lathe is now on Tonys site. I didn't realize is was that rare, to not even be listed in the ultimate online lathe compilation! Makes you a bit of a celebrity in these parts
Shawn
Shawn
12-28-2013, 11:02 AM
Aw, shucks.
12-28-2013, 12:10 PM
the right gear combinations you can cut a lot more threads then whats on the chart.
12-29-2013, 12:36 AM
David, I'm aware of that, and I do have all of the gears listed, so I should be good to go. For right now, though, I'm just glad to have the standard threads worked out.