Odd furrow like finish when taper turning?

I picked up a compound slide for the little C1 lathe to enable me to turn tapers last week but I've come across a weird problem when using it. When I turn a taper the surface of the taper has a furrow like finish? It is not the wavy finish you sometimes see from judder but more like the cutter is being drawn into the work and then deflected as the hand wheel is rotated. I've tried adjusting the gibs to take out the play but that didn't help, in fact it made things worse?

Any ideas guys?

Edited By Hollowpoint on 26/03/2019 11:36:31

make sure you turn the handwheel with both hands, don't crank it with the handle as that can lift and then lower the tool if there is any play. Failing that is the screw straight?

Poor finish on the gib strips on these things is not unheard of. Or the gib screws might just need adjusting?

If the gibs are loose it could be the tool tipping, ie rocking back and forth so altering tool depth. Make sure everything is tight but still movable. If you still get rocking r twisting then some remedial work is required to the slide and cross slide.

Stick some kind of smooth reference bar in the chuck (bit of silver steel perhaps or a bit of 1/2" bright bar) stick a clock on the tool post and wind your slide, do it with the clock horizontal (on the side of the bar) and vertical (on top of the bar) that will show you what if any movement you have. Rough and ready way of checking it before you look further at tool geometry / height.

Paul.

I tried tightening the gibs that didn't make any difference, Ill try the other suggestions see what happens.

Apron tight?

Just finished stripping the compound slide. There was a lot of old dried up grease on the slides so I cleaned all that off and like Hopper said the gib strip was quite poorly finished with lots of small burrs so I gave each side a rub on the wet stone to smooth it out. Reassembled with a dab of oil and it seems to have done the trick!

Thanks guys.