Motor upgrade?

[Munty Scruntfundle]

Hi folks.

Now the weather is warming up a bit I've been out turning a few large bowls. Well, as large as my lathe will allow, around 300mm. They're coming out well, very chuffed. Apart from the time it's taking.

While the Axminster 305 is a capable lathe, it's crap when you get to the larger diameters, it just doesn't have the power needed. I don't need more RPM, I need more torque. Axminster of course say nothing can be upgraded or changed.

I would upgrade the lathe, but I've done a fair bit making this one wheelchair friendly and the dimensions fit me well.

So... Are there any electrickery people here that could help advise a new motor, or how to choose a unit? Currently fitted is a 230v, 550w, ac 50hz, max rpm 1400. 750w would probably suffice, an extra .3 hp is actually quite a lot.

I have a reasonable electrical knowledge, but mostly with dc stuff and not this size. Any help gratefully recevied.

Many thanks.

 

[minilathe22]

I wasn't able to find that exact lathe online to compare, but if you find a motor with similar dimensions it is plausible.

You could also consider fitting different diameter pulleys to reduce the rpm and increase the torque at the headstock. How much room is there round the existing motor?

 

[sploo]

I take it it's not this one https://www.axminster.co.uk/axminster-c ... the-105119 (as it has a DC motor)?

If it's using an induction motor then they usually have frame sizes; such that getting the details of the current motor may allow you to find a similarly sized unit with a bit more power.

That said, the belt(s), spindle and bearings of the machine may only be designed to handle the stock power, and even that extra 0.3hp would be a ~50% increase in power. It might be OK if you don't push things hard too often though.

 

[topchippyles]

Be nice to fit a speed control switch just in case it gets to powerful ? Just thinking out loud

 

[Ttrees]

What type and size of shaft is on the motor?

You could always look around for a used 3 phase motor (one that is dual voltage) meaning it can be run by an inverter/VFD...look for 220 or 240v volts on the motor nameplate, or a TRIANGLE SYMBOL.
Often something like 220/380v
(Delta 240v household voltage, and Star 380v high voltage)

I believe it should be a 4 pole motor running at 1750 RPM or thereabouts, not double that figure.
You get easily adjustable soft start, adjustable speed with a potentiometer (a speed dial), reverse function, a jog function if that is any use, and motor de-rating on some, meaning you can get away with a bigger motor.

It would involve making a bracket or base for the lathe, and involve making a sheet metal box for the
VFD/inverter, but apart from making this, its as simple as wiring a plug.
You just have to do a bit of reading to make sense of the parameters (motor commands)
A small used three phase motor shouldn't set you back too much on fleabay.

Just giving an option
Tom

 

[Lazurus]

Sounds a lot of faffage when the bearings, shaft, frame etc may not be up the job. Will the lathe actually handle larger diameter and out of balance blanks? After 20 years of turning I now have a VB36 big green monster, this does tick all my boxes and will handle anything I can hang off it - BUT it was built to do this, not sure if I would invest the time and money to upgrade I waited and purchased the real deal. just my pennyworth.