Slow Monster rebuild

utopia · 23-03-2017, 12:56 PM

I've done a bit of turning ... shout up if you need any advice.

I wouldn't have thought you'd need a fixed centre ("pointed taper") at all on 25mm bar if the part you're making is only 25mm long .. as long as you do them one at a time.
It should be rigid enough without, particularly as its only soft ally you're cutting.
Also, paraffin is the best lubricant/cutting fluid for ally, and will stop swarf welding itself to the tool point. (and incidentally, is also useful to stop files clogging if you're doing any of that on ally). Apply it with a kids paintbrush, during the cut.
Try to cultivate the habit of turning the chuck one revolution by hand before starting up, to check for clearance.
I assume you know all about eliminating the effect of backlash in the slide threads by always winding out and then back to your chosen mark.
And finally for now, NEVER leave the chuck key in the chuck ... std workshop safety practice to avoid it being slug at your teeth when you switch on.
Oh, and also beware of "parting off" operations. Shouldn't be a problem on soft ally but on tougher materials the tool can easily drag itself into the workpiece and cause a foul-up, particularly if the tool height is set a tad low. For parting off, the tool should be set dead on centre height or even slightly above, to reduce thus tendency. Or do as I do and get out the hacksaw ... its often quicker than setting a tool to part off just one or two pieces.

Hope some of that is helpful, without being patronising.

Oh, and a useful way to check your tool height setting is to trap your thin, 6 inch rule between the tool point and workpiece and then view it from the tailstock end. It will be dead vertical if the tool is spot on centre height, but slanting if not.
Slightly below centre height, or spot on, is what you want .. never above or obviously the tool will rub rather than cut (unless for parting off, as mentioned above).

23-03-2017, 12:56 PM	#11
utopia No turn left unstoned Join Date: Jun 2010 Location: leicester Bike: M750 Posts: 4,546	I've done a bit of turning ... shout up if you need any advice. I wouldn't have thought you'd need a fixed centre ("pointed taper") at all on 25mm bar if the part you're making is only 25mm long .. as long as you do them one at a time. It should be rigid enough without, particularly as its only soft ally you're cutting. Also, paraffin is the best lubricant/cutting fluid for ally, and will stop swarf welding itself to the tool point. (and incidentally, is also useful to stop files clogging if you're doing any of that on ally). Apply it with a kids paintbrush, during the cut. Try to cultivate the habit of turning the chuck one revolution by hand before starting up, to check for clearance. I assume you know all about eliminating the effect of backlash in the slide threads by always winding out and then back to your chosen mark. And finally for now, NEVER leave the chuck key in the chuck ... std workshop safety practice to avoid it being slug at your teeth when you switch on. Oh, and also beware of "parting off" operations. Shouldn't be a problem on soft ally but on tougher materials the tool can easily drag itself into the workpiece and cause a foul-up, particularly if the tool height is set a tad low. For parting off, the tool should be set dead on centre height or even slightly above, to reduce thus tendency. Or do as I do and get out the hacksaw ... its often quicker than setting a tool to part off just one or two pieces. Hope some of that is helpful, without being patronising. Oh, and a useful way to check your tool height setting is to trap your thin, 6 inch rule between the tool point and workpiece and then view it from the tailstock end. It will be dead vertical if the tool is spot on centre height, but slanting if not. Slightly below centre height, or spot on, is what you want .. never above or obviously the tool will rub rather than cut (unless for parting off, as mentioned above).