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Polie
1st Feb 2010, 10:57 AM
Hi,

I just got myself a small lathe for the wife and myself (okay, she can use it if I don't need it right now :))

Tow questions.
1. I am about to build a bench to sit the lathe on. What are the rule of thumb for setting the height of the lathe?

2. The lathe has 6 Speeds - 360 to 3,250rpm. Is there a speed table, similar to the drill bit speed chart I use, to show what each speed is used for?

Thanks,
Chris

Ozkaban
1st Feb 2010, 11:45 AM
Welcome to the madhouse!

Both questions have lots of variables, and even more opinions. So what the heck, here are mine :D

Height of the lathe should be whatever is comfortable, but as a general rule, if touch your shoulder with your opposite hand, the point of the elbow should be at about spindle height. But as I said, whatever you feel comfortable with.

Second question is more like if the lathe is wobbling a lot, slow down. If it's not and isn't cutting as cleanly as you like, speed up :D Sanding is usually done at a slower speed as there is less heat build-up.

Pens would be max RPM, big wobbly bowl blanks the slowest. Maybe somebody else has something more accurate :rolleyes:

Cheers,
Dave

artme
1st Feb 2010, 11:45 AM
Another turner!! Good stuphph!!!

General rule of thumb for height is to have the spindle centre at about elbow height.

Speeds: generally the smaller the diametre the faster the speed. Lots of people like to turn pens at The highest available speed but some turn ut speeds about 1800 to 2200 rpms.

Once larger blanks have been balanced then choose your own speed within your capabilities.

With sanding you need to slow the lathe down as the heat build up can cause problems with surface cracking, or worse.

Allen Neighbors
1st Feb 2010, 01:22 PM
Good advice from all. Welcome, too!
The only difference is height. I'm 5'10" tall, and I have the spindle height on my large lathe at just over 49". I just helps me out, because my back was giving me fits at lower height. I now sit down at my small lathe.
Build it, try it, and if you don't like it, add or subtract some height using shims... when you get it the way you want it, make it permanent. Luck to you.

Polie
1st Feb 2010, 01:40 PM
Thanks guys,

I guess the lathe height will need to be a compromise because I stand at 180cm (about 5 11) and the wife at 160cm (20cm shorter than 5 11 :)
She is easily spooked by machines so I hope to start her on pens as she will have less fear of a pen flying out rather than a monster lump of jarrah.

I would have thought there would have been an optimum speed for wood against the cutting tool and therefore recommended speeds for different diameters of wood.
The max diameter I could possibly put on the lathe is 600mm and a pen is likely to be the smallest. I suppose if I made my own table/chart with 600mm at 360rpm and 10mm at 3250rpm and figure out the 4 other speed settings and diameter ranges then adjust as the school of hard knocks dictates.

Most of my turning will be either hard woods (jarrah and the break your chainsaw type woods we have in mid west WA) or soft woods (pine). Is there a rule of thumb on the speed you turn each at?

Thanks,
Chris

RETIRED
1st Feb 2010, 02:46 PM
There are too many variables to give an accurate "this diameter turns at this speed" kind of answer.

How heavy is the lathe?
How well is the lathe mounted?
Is the timber dry or wet?
Is the timber machined or log?
How big is the timber?
How quick can you get it round?
Etc, Etc as the King of Siam said.

Rule of thumb is let common sense and experience dictate the speed. Start on lowest speed, if it doesn't vibrate go up to the next speed.

When it vibrates, go back one speed.

hughie
1st Feb 2010, 05:09 PM
Thanks guys,

[QUOTE] I guess the lathe height will need to be a compromise because I stand at 180cm (about 5 11) and the wife at 160cm (20cm shorter than 5 11 :)
She is easily spooked by machines so I hope to start her on pens as she will have less fear of a pen flying out rather than a monster lump of jarrah.

Make a set of floor boards or similar to match her height requirements and set the lathe to suit you. :2tsup:


I would have thought there would have been an optimum speed for wood against the cutting tool and therefore recommended speeds for different diameters of wood.
The max diameter I could possibly put on the lathe is 600mm and a pen is likely to be the smallest. I suppose if I made my own table/chart with 600mm at 360rpm and 10mm at 3250rpm and figure out the 4 other speed settings and diameter ranges then adjust as the school of hard knocks dictates.

well it kinda depends on a whole bunch of variables and pretty well summed it up. Best thing is to get involved with local club or chapter on turning, here you will get all the advise and mentoring at first hand. :2tsup:





Most of my turning will be either hard woods (jarrah and the break your chainsaw type woods we have in mid west WA) or soft woods (pine). Is there a rule of thumb on the speed you turn each at?


yeah, if it keeps coming out of the chuck, slow it down :U

issatree
2nd Feb 2010, 12:00 PM
Hi Polie,
My piece of advice is 1st., make a Duc Board to stand on. Strips of wood 50mm. wide , x 1220mm.long, from a Refrigerators Packing Boards,(Retrovision store etc. )
Sit them on 4 or 5, 100mm. x 50mm. 920 long, 30mm. apart, glue & screw, NOW you measure, from your Duc Board to 25mm. above your elbow, which is the height of Lathe Centre.
By Standing on your D/B. you will not be standing Shavings & rubbish, from the Lathe.
A lot better on the Legs, & more Comfortable, as it will be a bit Springy as well.
My other comment is to put your Lathe on RAILS not a bench, then all you shavings fall to the floor. I actually have 2 rubbish cans under the Lathe, & this catches a fair amount of the Shavings, so, not much to clean up afterwards. Hope the explanation is OK.
Regards,
issatree.
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Polie
3rd Feb 2010, 11:14 AM
Thanks Issatree,

I ended up grabbing a small height adjustable desk from my office and mounting it on that, wound all the way up suits me and the wife can adjust it down for her. The desk seems to weigh 30kg and is surprisingly stable.

I forgot all about having something soft to stand on, I have it for all my other machines and bench but I guess my brain was going to wait until my feet got sore before reminding me to do something about the lathe.

The lathe is mounted right on the front of the desk so currently I just collect all of the wood chips in my socks then empty them out inside the house. I may need a different approach if I wish to remain married http://cdn.woodworkforums.com/images/smilies/smile.gif

Chris