sapwood
Aluminum
- Joined
- Dec 7, 2013
- Location
- sunderland
Hello, im jonpaul from County Durham, N.E UK. I have a small amount of experience with metalworking lathes, used to use a Barker. Recently bought an imperial chippy and ive messed around for a few days to farmiliarise myself with it. One project I recently just began was to start making faceplates for various woodworking lathes, mainly my own Harrison Jubilee which doesn't have a bowl turning faceplate. This plate is an internal left hand 1" 10TPI BSF thread. So ive made up my 60degree cutting tools from HSS and ive practised on some scrap bar beforehand. This practice brought forward a whole host of problems that have really knocked my confidence in any part of this thread cutting process. Before I began I figured I had it all worked out, until I began cutting and realised the following.
1) What I though I understood the TPI and gear charts just doesn't seem to figure out right as the actual thread being cut doesn't correspond at all to the chart. I had selected gear selector number 4 of 9, and the ABC selector gave me an option of either A or C as both on the chart produce a 10tpi, but in practice both cut a 9tpi, just short of 10tpi.
2) Also working out when to engage so that the cut drops in at the exact, precise point at each pass is proving problematic, despite understanding how the saddle is moved up and down the bed by using the thread dial. The problem to me seems to be that the chuck to me doesnt seem to be synced with the leadscrew? Im making this presumption upon limit knowledge by the way. The only thing I can think of resolving this is by setting up the whole machine ready to make a first pass and marking the chuck, leadscrew and saddle positionupon the bed and making references after each pass when setting up again? I know this will resolve my problems, but at the same time I know that this machine doesn't have to be used in this manual way, but working out the correct procedure of this process for this chipmaster is going over my head at present and im needing some help.
Also having to cut this left hand internal thread without this lathe having a reverse isn't the easiest of first projects, as firstly I have to cut from left to right and from within the workpiece, which you cant really see, or is indeed limited even if you leave a small gap between the piece and the chuck.
The way that I was having to cut this practice thread just didn't seem to work right at all.
I would benefit an awfull lot if to fully understand all the controls, the charts and the chippy way of cutting threads if you could help me out here. Their seems to be little on the net that explains and no tutorials on youtube. Ive read the manual which has left me with only a very basic knowledge, but not a great understanding of the controls and the process. The crazy thing is the manual explains the basic functions of the controls and then goes into crazy expert theory on multistart threads and some advice on gears etc for metric threads on an imperial machine?
I would be a very happy guy if I am not resorted to having to throw in the towel and shell out a small fortune on taps to do these weird and wonderfull threads just because I don't understand the tool already at my disposal that can invariably allow me to do the job.
Thanks very much and look forward to hearing from you sometime soon.. JonPaul
1) What I though I understood the TPI and gear charts just doesn't seem to figure out right as the actual thread being cut doesn't correspond at all to the chart. I had selected gear selector number 4 of 9, and the ABC selector gave me an option of either A or C as both on the chart produce a 10tpi, but in practice both cut a 9tpi, just short of 10tpi.
2) Also working out when to engage so that the cut drops in at the exact, precise point at each pass is proving problematic, despite understanding how the saddle is moved up and down the bed by using the thread dial. The problem to me seems to be that the chuck to me doesnt seem to be synced with the leadscrew? Im making this presumption upon limit knowledge by the way. The only thing I can think of resolving this is by setting up the whole machine ready to make a first pass and marking the chuck, leadscrew and saddle positionupon the bed and making references after each pass when setting up again? I know this will resolve my problems, but at the same time I know that this machine doesn't have to be used in this manual way, but working out the correct procedure of this process for this chipmaster is going over my head at present and im needing some help.
Also having to cut this left hand internal thread without this lathe having a reverse isn't the easiest of first projects, as firstly I have to cut from left to right and from within the workpiece, which you cant really see, or is indeed limited even if you leave a small gap between the piece and the chuck.
The way that I was having to cut this practice thread just didn't seem to work right at all.
I would benefit an awfull lot if to fully understand all the controls, the charts and the chippy way of cutting threads if you could help me out here. Their seems to be little on the net that explains and no tutorials on youtube. Ive read the manual which has left me with only a very basic knowledge, but not a great understanding of the controls and the process. The crazy thing is the manual explains the basic functions of the controls and then goes into crazy expert theory on multistart threads and some advice on gears etc for metric threads on an imperial machine?
I would be a very happy guy if I am not resorted to having to throw in the towel and shell out a small fortune on taps to do these weird and wonderfull threads just because I don't understand the tool already at my disposal that can invariably allow me to do the job.
Thanks very much and look forward to hearing from you sometime soon.. JonPaul