Lathe Speeds

[wcndave]

The instructions on my lathe seem to indicate that the larger the diameter of the piece, the faster I should run the lathe...

surely that's wrong?

what is a good speed for spindle turning abut 6cm diameter? I am trying now at 2000 and it's much much faster, however catches feel much more dangerous.

 

[Vic Perrin]

Hi, A Golden rule - The bigger the piece the slower the speed. With large pieces always start of on the slowest speed and gradually increase when you get the piece in balance.

Regards

Vic

 

[wcndave]

Hi, A Golden rule - The bigger the piece the slower the speed. With large pieces always start of on the slowest speed and gradually increase when you get the piece in balance.

yes, that's what i thought. only sensible way really.

I am nearly always turning small pieces, eg the bird houses, and spinning tops from other posts. They are all about 6cm diameter, so i assume 2000 is ok, although catches do give one quite a start at that speed!

 

[Woodchips2]

If you feel nervous at 2000rpm then turn at 1000rpm initially and finish off at 2000 when you're less likely to get catches.

Regards Keith

 

[chipmunk]

Dave,
I agree with your reading of the advice label on your lathe - it's completely A about F !

Given the litigation society we live in now then Scheppach should get ready for some claims :wink:

Jon

 

[CHJ]

That lathe chart is certainly incorrect, the lower diameter figures should be reversed.
A guide to turning speeds can be found here

 

[wcndave]

Unusual for the Germans to get it wrong. Must be made in China. 2000 feels great,I have been turning at 1000 and this is so much smoother, except when I get a catch ;-)

Sent from my GT-I9100 using Tapatalk 4

 

[paulm]

What are you doing when you get the catches Dave and what tool are you using ?

Regardless of speeds it would be good to see if we can iron out some of the causes for you and then you'll be able to relax and enjoy the turning a bit more, be safer too

Cheers, Paul

 

[wcndave]

I mostly get catches when doing convex curves, either with skew or spindle gauge, it's not that often, although it only has to be once per piece to have zero output!

just need to keep practicing.

 

[Random Orbital Bob]

So......when coming downhill on the side of a bead sounds like its your problem? I must say that's where I get most of my catches too when doing beads.

Two things spring to mind:
1/ Are you rolling the spindle gouge in the same direction as the destination as you do downhill on the side of the bead? In other words if you start at top dead centre of the bead and then come down its left slope as you look at it....the gouges flute should rotate in the direction of the headstock at the same time as you move downhill. This keeps the bevel rubbing as it follows the radius and keeps the catching edge away from trouble.

2/ Its worse with a skew...much worse in fact. Its critical to roll the skew around the radius as you go downhill or the corner catches and boom...ruined.

For me I found watching Richard Raffan vids and you tube etc invaluable as a tutorial for technique and then just mindless practice with a skew. My kindling has to be the most beautiful around here...all beaded spindles

 

[Random Orbital Bob]

But I will say one thing that's important. The skew is a bitch at first but I'm really getting the hang of it now and it's an absolute joy when it comes together because it cuts the wood so cleanly and your starting points get really accurate. You get the satisfaction of those really crisp edges on spindles with minimal breakout. I was very frustrated at first but I'm glad I persisted through that stage and I would really encourage you to put the time in to the practice because its the key to the world of the skew really. Apart from TC tipped scraper tips which don't leave as cut a finish...there is no short cut.

 

[paulm]

The problem with the spindle gouge is probably the easier of the two to address, the skew takes a bit more practice as Rob says !

As well as the thoughts above I would be interested to just check on the grind and shape of the spindle gouge end ? If it is sharpened to a very pointy and acute angle it may be difficult for you to keep the bevel engaged and rubbing on the wood and lead you to using the tip in an unsupported manner occasionally which will lead to catches.

Similarly you should only be cutting "downhill" on the curve, if you try and cut "uphill" you are going against the grain of the timber and catches are more likely.

A few things to think about anyway Dave, I'm sure others will have a few thoughts too.

Cheers, Paul

 

[wcndave]

Thanks. I do roll in right direction etc, and I am fairly sure it's just a practice thing. I often get the spindle ones when i make the first incision, rubbing away, then lift, perhaps a little to aggressively, impatiently, and boom...