no experience of three phase but i also had severe vibration when using the highest speeds on my S7.
i changed my V type drive belts to the link type and the vibration all but totally dissapeared.
£50 is a hell of a lot cheaper than paying 100s of pounds for 3 phase simply to get rid of vibration

z

Edited By Ziggar on 01/10/2014 23:18:14

Hi Brian, are you thinking of the complete kit or a DIY set up? The DIY route is not difficult and can be cheaper. Whichever you go they are worth the effort, it will quite transform your lathe.

Re vibration possibly due to belts, are you using "cogged" belts and do you release the tension when not in use to reduce the risk of putting a set in them.

chriStephens

I have found that if the belts are left under tension when the lathe is not in use they take up a "set" which causes vibration until the machine settles down again. I always relax the belts after use to avoid this problem and so far it works.

I too have a S7 which I fitted with a 3ph 1HP motor. The change is a huge step in performance in the speed control, power and smooth running. I very rarely change the belt position because with the power and speed control, even thread cutting can be undertaken without back gear but at low speeds, the motor temperature has to be watched

Before buying an expensive package, consider buying separate items. Motors are readily available, but check that it is the type with six terminals, other wise is can be a bit tricky to locate the star point which requires a motor to be dismantled( motor rewind people will fix it at a price, easy if you know how). Inverters are available on the net from the Far East and ebay at a good price and there appears to be lots of helpers around if you get stuck with the set up. Should you need a remote control package, they are easy to make up and the bits area available from Maplins.Three phase motors are inherently smoother in operation 12 pulses a rev as apposed to 4. Also 3 phase motors are simpler than single phase, no switch, capacitor or start winding to go wrong. Regarding the belts have a trip to your local bearing factors, they will have a range of belts suitable for Myford lathes and I have found half the price of the lathe dealers.Ted

I suggest you talk to Transwave whose ad should be just to the right and up a bit from here—>

If you mean Rotagrip near Hockley flyover in Brum, Transwave are pretty nearby in Tyseley.

Neil

Edited By Neil Wyatt on 02/10/2014 13:50:50

Hi Brian,

The cheepest 1HP 1400 rpm 3 phase motor I could find was item number 110912538780 on eBay It was £82.00 I have just looked and there are 4 left It works fine with Teco inverter also bought on eBay for £55.00

Les

( Sent from my Nexus7 sitting on a beach in Rhodes Greeece))

Edited By Les Jones 1 on 03/10/2014 09:31:59

.

True, Neil … but thankfully the mounting plate arrangement is very simple.

Most significant points will probably be (a) the shaft diameter and (b) the fact that the original Myford fit motors are vibration isolated [this I doubt will be any problem if changing to 3-Phase & Inverter, which is much smoother]

MichaelG.

I have a Super seven and a fobco drill both purchased new over 40 years ago,both have the original motors and drive belts,neither of them vibrate and both have had a lot of use earning me a living,I have never required or desired to make changes to the Myford, On the other hand 1/2 inch capacity bench drills usually have a bottom speed of 450 to 500 rpm which can be a pain when reaming or straining the drill with over capacity drills, I had a need for larger capacity drilling so bought a used1 inch capacity Meddings ,with low sped of 100rpm which gave reamers an easier life and allowed the use of a tapping attachment. A while back out of curiosity after reading lots about electronic speed control on this forum I looked up the cost of a speed control on the fobco,it was a lot more money than what I paid for the Meddings.

Is the vibration being experienced due to modern motors being imported and not being so good as the old uk built motors,as there were never any moans about single phase motors in the dim and distant past,a solution could be find a good used uk built motor. My father bought a brook gryphon motor in 1950 to drive saw bench and has been used since to power lathes (wood and Metal) and now drives my power hacksaw daily,a very good motor.

The 1/2 hp kit I used should suit a Myford, but I suggest asking Transwave for advice.

Neil