New toy: Setting up Colchester Student lathe

[Web Goblin]

Jonathan,
I hpe your are havng more fun with your new toy than I am with mine. My "new" Blomqvist is cutting at a taper. I spent a while last night setting up the tool holder ang cross slide with a dti guage so that it is at 90 degress to the chuck and it is still cutting a bit off. I have bored out a hole with the apron stationary while using the cross slide compound rest. Still not sure why it is tapering. It could be that the headstock is slightly off centre. I will need to check this later.

Ian

[Jonathan]

Jonathan,
I hpe your are havng more fun with your new toy than I am with mine.

I've not actually made anything wit it yet - I'm trying to think of something!

My "new" Blomqvist is cutting at a taper. I spent a while last night setting up the tool holder ang cross slide with a dti ... It could be that the headstock is slightly off centre.

When cutting parallel I always use the apron handle for the final pass. If you use the apron does it cut parallel, if not it must be the headstock.

Where are you putting the dti to test the top slide since the side of it might not actually be exactly parallel to the direction of motion? How far off is it? If it's only a very slight taper using the apron handle it could be that the bed is twisted.

I've not checked the headstock on mine yet.

[M250cnc]

When cutting parallel I always use the apron handle for the final pass. If you use the apron does it cut parallel, if not it must be the headstock.

Where are you putting the dti to test the top slide since the side of it might not actually be exactly parallel to the direction of motion? How far off is it? If it's only a very slight taper using the apron handle it could be that the bed is twisted.

I've not checked the headstock on mine yet.

The compound slide should only be used FOR cutting tapers, everything else you should use the saddle/apron

The only way to test is with a test bar that fits in the spindle taper and use a dti any other method you will be bringing other factors into the equation by making test cuts "Tool Deflection, Materiel Deflection ETC"

The only part that needs to run true is the cross slide to the spindle axis.

Phil

[Jonathan]

The only way to test is with a test bar that fits in the spindle taper and use a dti any other method you will be bringing other factors into the equation by making test cuts "Tool Deflection, Materiel Deflection ETC"

That's interesting, and seems logical, however in the manual for my lathe it says to test it by cutting.