On Sun, Sep 12, 2021 at 01:14 PM, OldToolmaker wrote:
Keith,
I did not buy this unit. It was given to me by my brother who had no use for it. I have nothing invested in it.
Do you still feel it is a waste of my time and money?
Dick
Free is good. Also bird in hand V birds in bushes, etc.
You will need to look for a 90 V motor, either permanent magnet (two wire) or with separate field and armature connections (four wires). I have no idea how easy or difficult this might be. There are some technicalities in section 7.2 regarding supply voltage and motor voltage that you might need to pay attention to. The 1 ohm braking resistor could be any ceramic bodied high wattage one that will fit in the available space. I don't think its going to do much work - the time spent braking compared to running or stopped will be short, so not much energy gong into the resistor. It's not clear from the manual how the resistor fits.
Just avoid going to a high power motor. 130 W is plenty for these little machines, so about 1/5 or 1/6 HP. Too much power just means more damage when things go wrong. The big thing is to find a motor that fits in the available space and is convenient for the pulley.
It looks like you can connect a remote pot, so you could put the control knob nearer the lathe, if there is a suitable space. I think that having it handy makes a big difference.
The only hopeful one I can see searching on 90V DC motor is Ebay item 124453615832. All the rest are industrial motors that will be bigger than the lathe, typically rated at ? HP..
Data sheet here, see page 9/19:
It looks like it's 80 mm diameter, with a 90 mm square flange, so I don't know how easily that will fit. The length is not too bad at 142 mm, but the shaft is a helical cut gear, so it will need adapting. The rated speed is only 2800 rpm, so it's a bit slow. You could then make alternative pulleys to get the speed up. The maximum speed on the controller can be set to 110%, so you might gain a bit there.
Judging from Ebay it will not be so easy to find a suitable motor. Nearly everything I see is high power, high price and too big.
Ebay 262563151794 might be worth considering. Compact, high speed, right voltage and cheap, but it would need a housing to keep swarf out of the motor, and something to limit the maximum speed, unless you really want in excess of 10000 rpm.
Ebay 271445592760 is something similar available from within the USA, and cheap enough to be worth a try. Only rated at about 100 W but capable of taking a short term overload, allowed by the controller.
