Myford ML7, New lathe and I have questions.

[lordedmond]

Hi don-tucker,

Valuable tip!
I might rethink the belt issue, as removing the spindle also would give me a possibility to evaluate the bearings etc.
Ill ponder on it a bit, thanks for the tip.

Orjan

i will say one word poly belt opps that was two ;D

 

[Orjan72]

i will say one word poly belt opps that was two ;D

Oh no, now you've done it..... :noidea:

I'm trying to be sensible here people, taking it one step at a time, getting the dear old girl up and running, making chips and most of all avoiding giving in to spending far too much money on something I bought on a whim (read: without permission from missus...) *club*:big:

Seriously though, I think you are right, but it involves a bit more machining then I'm up for right now. The great thing is that even if I get linked belts now, in a year or two I can still convert to poly.

Orjan

 

[lordedmond]

the reason for my cryptic post is that I had a old ML7 , it use to eat belts due to the oil ,I too have tried the twist loc belt and to had the slippage problem
( others have had more luck)

since I shelled out for one of the new ones over a year ago the poly belt look like new no slipping silent running , couple the poly belt mod with a 3 phase motor with VFD inverter you are golden

do not use RPM over the 600 or so that it is now because the babbits will not like it , the new machines rev to 3000rpm in two ranges with back gear on the lower range only


Stuart

 

[Niels Abildgaard]

If You use Power twist belt You have to observe the very small arrows that indicates normal running direction.
There is a small difference and how do i know?Apart from that I think they must be work of a genious.

 

[Ned Ludd]

Hi Orjan,
You can keep the motor and use an inverter, you just have to modify the internal wiring. I suspect your motor is too old to be dual voltage, but a couple of hours of fun with a soldering iron, some heat shrink sleeving, a goodly length of thread and some insulating varnish will see you up and running, oh and add an inverter to the list.

An inverter is usually cheaper than a converter and is certainly quieter. If you are going to use an inverter for speed control, go for an 'advanced vector control' type.
If you a only going to use it to supply three phase and use the original belt swapping to give different turning speeds then the cheaper type would do. The cheaper ones work fine in the 40-60 hertz upwards range, but they lack power low down.

I made the mistake of getting an entry level inverter for my Myford Super7B, but with that experience I got a better one for my other lathe. Having said that, I would not be without my inverter powered Myford for all the tea in China, especially as I only drink Coffee. ;D Once you have had variable speed you will be reluctant to give it up.
Going back to the quieter bit I mentioned above, one of my two converters used to drive me mad (only a short journey that one) with the noisy "Kerchunk" every time I started the motor. . the other one used to Hum noisily, which was a constant irritation. My inverters are much quieter and the lathe motors seem to run more sweetly too.
Ned

 

[njl]

Hi Orjan,

I use a transwave rotary convertor for my three phase machines. You just connect one side to the mains and it makes 415V three phase at the outlet. Just wire it in and your good to go. It does make a noise as it has a running motor. But it can work several three phase machines at the same time which I was told some of the electronic jobbies can't. I have three phases of mains coming into my premises but with each phase terminating in different buildings, the cost the electricity company wanted to terminate the missing two phase to the work shop was extortionate, (for what was effectively two bits of wire through a wall and two extra electricity meters.) which is why I went the convertor route. I've been very happy with transwave kit.

Nick

 

[Orjan72]

Hi Ned and njl, I got an inverter from a friend, capable of variable speed. I'll post specs and image shortly. I never connected something like this and I'm clueless when it comes to 3 fase ( or electricity in general, its all magic to me ;D). wish me luck! (I'll consult someone mastering the dark art of electricity before plugging anything into the mains)

Orjan

 

[Orjan72]

Had a look at the cross slide. It had too much play due to worn out bushing. I made a new one (Ø12mmx2mm) out of brass, cleaned,lubed and mounted. Tight like a tiger
The original bushing was a nylon something or other and completely mashed.
Maybe later I will remake it in teflon as I'm making a part for a boat that involves a teflon bushing.

I will try the linked belt, It will allow me to get the lathe up and running and then later decide if I will convert to poly. Me and my girl are thinking of building a workshop next year with separate metal and wood workrooms (she is an arts and crafts teacher). Then I will probably get more of a system going as well as some heat in the winter. A good incentive to make the poly conversion :big:

I have not got any further on the 3 fase motor other then it is an Euromoto and is capable of 220-380V. The inverter I got is a fairly serious bit of kit and I think it will do nicely (until my mate wants it back ) By then the new workshop is hopefully complete with 3 fase outlet.