Thread: Waldown 8SN VFD conversion

Very nice drill press. I got the bench top workman version, same motor.

I followed BobL's guide that you can find here in this forum and converted it into 1ph , I had to take motor apart and traced the wires then extended them. It was not hard to do.

Hoey

That motor is a star or "Y" connected motor and will need to be converted internally to delta (∆) run at full power on a 240V 3Phase VFD.

This is a job best done by a motor rewinder.

I'd start by having a read of the PDF link on this page
VFDs for Newbies

Then ask more specific questions from there.

Originally Posted by jonsey850

The motor plate doesn’t say whether the wiring is star or delta but the full load amps states 2Y?

Also there are only 3 wires coming from the motor so likely have to get the other 3 brought out?

actually the Y is upside down compared to the 2, so the motor plate did actually tell you the answer
Looks to be a nice quality motor and looks still in good nick overall

Thanks guys I had a read of the guide seems pretty straight forward. Will take the motor off tonight and take it to the motor reminders.

Hi Poundy it was from a school, the kids have given it a little treatment but it’s not too bad everything seems tight still. The pin for the depth stop it a little loose I imagine from them letting the handle go rather than easing it back.

Also the original handles are missing I’m guessing the cool kids [emoji41] stole them, looks like the teacher might have made the replacements.

Rang the local rewinders (Capricorn rewind) - they wanted $600 to bring the wires out [emoji15].

Rang another place in Gladstone (150km away) and the guy said it’s easy on that motor just disassemble and bring it in and he will show me what to do for nothing or do it for a reasonable fee. I travel there for work occasionally so easy done.

Originally Posted by jonsey850

Rang the local rewinders (Capricorn rewind) - they wanted $600 to bring the wires out [emoji15]. .

That means they don't want to do it. The most I have ever heard of anyone paying was $150 and I reckoned that was steep. Typical prices are round 1/2 to 2/3rd that.

Rang another place in Gladstone (150km away) and the guy said it’s easy on that motor just disassemble and bring it in and he will show me what to do for nothing or do it for a reasonable fee. I travel there for work occasionally so easy done.

That's better

Yeah they are all too well fed from the mining industry around here.

Any recommendations on VFD?
I know you like the Powertran items Bob .

Ok some great success tonight, I have dismantled the motor quite easily.





No idea what to look for from here on but I’m guessing the star point is wrapped up somewhere up the top of the windings there. Anyway will try get it to a rewinder tomorrow.

Cheers

The common or star point will be inside one of those yellow sleeves.
The cotton thread will need to be cut way and then a plastic spatula will be need to pry the junctions off the resin
The star point can be distinguished by the fact that it will have 3 wire brazed together with a solid little ball of copper.

This thread will give you some idea of the trickiness involved.

Tricky Y common point excavation

If you slip and break one of the wires off inside the coils - well then, the excreta has really hit the fan.

Thanks Bob

I think your right about taking to a rewinder. I do like to do things for myself but I’m not willing to risk breaking any of the wires on this motor.

Got new parts for the table lift from Waldown. Very good service overnight express posted, A+.




The school kids had completely destroyed the original worm drive and wheel. Most likely done by winding the handle while the table is clamped.




Motor still at the rewinder, apparently will be complete next week.

Cheers

Motor returned from the rewinder. It was a long turn around but I have to say he has done an impressive job. The windings were varnished and placed in an oven overnight.

He said this motor should handle the VFD well as it has thick insulation. He also offered a decent price on an Invertek drive so I obliged, it will be here early next week.

The Invertek drive showed up today.
I made a mounting plate for it thisarv.







I got the version with the built in controls to save having to have to place it in a box and use an external pot, fed/rev switch & isolator.

This may have been a mistake as the switches don’t feel very nice to use. Fingers don’t really fit between the dial and the edge of the recessed face. My fingers are not large, so those with big hands would likely have a problem.

The isolator switch requires a lot of force to turn and the plastic switch is pretty flimsy. I feel like with extended use it may fail.

But anyway hopefully it works better than the first impressions.