Lathe Speed gauge

[henton49er]

Does anyone know of a simple (and inexpensive) device that I can sit on top of my headstock that will give me a readout of the rpm that my lathe is turning? I have electronic speed control on 5 different pulley settings, but no speed readout. It would be nice (but not actually essential) to have some idea of the speed of the lathe.

 

[DTR]

Use a bicycle computer. I picked one up on e**y for a few pounds. The one I bought had an rpm function, but some only have a speed function which is dependant on the bicycle wheel diameter. By doing a bit of maths and entering a certain "false" diameter it will give you an rpm reading instead of speed.

Hope this helps

 

[cambournepete]

That's a neat idea. I also have a lathe with that set up but just guess the speed or adjust to what feels comfortable and safe.

 

[nev]

is 12.49 cheap enough? and its in Wales!
http://www.ebay.co.uk/itm/New-Digital-L ... 3372f68f8c

I have no idea how or if it works but it does specifically say 'accurately measure the speed of a lathe'

 

[CHJ]

Make yourself some strobe discs and mark up a simple scale to place around your speed adjustment knob.
more than accurate enough until you get used to the machine, once you have used it for a while you will be able to select a given speed range by ear without even looking at the settings.
Printable calibration discs HERE

 

[henton49er]

Thanks all for the feedback.

Dave - that's an interesting idea - but I would have to get my brain around putting in a false wheel diameter to give an rpm readout!!

Nev - this looks like a hand held device, rather than something that can sit on top of the headstock and give me a continuous reading of the lathe speed

Chas - a good idea, except that I cannot see my speed control knob without crouching down (the inverter with on/off and speed control sits sideways on a shelf beneath the lathe bed - the on/off buttons are at the front, the speed control on the side). I also have five different pulley positions so would need 5 different bands on the paper speed guide!!

Some food for thought!!

 

[Jonzjob]

This loos the same. It works with the light reflected from the 'reflective tape you stick onto the drive shaft/chuck or whatever you stick it on.

http://www.ebay.co.uk/itm/Digital-Laser ... 0661987166

 

[henton49er]

This loos the same. It works with the light reflected from the 'reflective tape you stick onto the drive shaft/chuck or whatever you stick it on.

John,

I think this is a similar device to the one that Nev directed me to - the problem is that it is hand held and therefore only gives readout if you pick it up and point it at the lathe. I was ideally looking for something that would give a readout all the time without any action on my part, once it was set up on the lathe.

 

[CHJ]

I doubt that there is anything 'off the shelf' that will do what you want to do.
If you look at the link I referenced above you will see the need for some form of spindle RPM counter as a reference for any remote meter or display to work with.

 

[Mike Wingate]

The hand held device is a great idea. You could easily incorporate it by the lathe to give you a readout. Foot switch, mirrors etc

 

[nev]

This loos the same. It works with the light reflected from the 'reflective tape you stick onto the drive shaft/chuck or whatever you stick it on.

John,

I think this is a similar device to the one that Nev directed me to - the problem is that it is hand held and therefore only gives readout if you pick it up and point it at the lathe. I was ideally looking for something that would give a readout all the time without any action on my part, once it was set up on the lathe.

Surely what double sided tape was invented for :mrgreen:

You could pm aled and see if he had any success with a similar project? .... diy-rpm-meter-t58231.html

 

[dennisk]

I repowered my old BL150 with variable drive and was wondering what my speeds would be. One of my friends run a truck repair shop and he has a dial type indicator that is held on the shaft and gives a readout. I did that on each speed at full power and half power, and recorded these. Wrote it down on a piece of paper and it sits on the wall by the lathe. Easy peasy to get a fairly close idea of speeds just by looking at the dial on the drive.

As an aside, has anyone rebearinged one of the these? Thanks DK

 

[graduate_owner]

Hi,
nothing to do with this topic, but I was just wondering:-
do people find their 3ph motors have very little torque when the inverter is set to really low speeds?

Also, a question for Nev, where about at the greener and wetter end of the M4 are you? I'm 30 miles West of the end of the M4 - foot of the Cambrian mountains!! (and yes, it's quite wet here too)
K

 

[12345Peter]

Hi,
nothing to do with this topic, but I was just wondering:-
do people find their 3ph motors have very little torque when the inverter is set to really low speeds?
K

I think you have options in the parameters to change the torque.

Regards
Peter