Wtb tp 4070cm

[donhuff]

I'm needing a rotor for a TP CM 4070. 2 or 4 pole doesn't matter. I just need the rotor but I will buy complete motors also. Either good ones or burned up ones. If Burned, It still needs to turn over to prove that the rotor isn't blown up.

[HTVboats]

I'll check my hoarders box I probably have something.
Mic

[HTVboats]

Don I move my workshop into a 6X12 trailer and had a box of burnt motors I just can't find in the trailer or my garage. It will turn up someday as I never throw anything away. (hoarder)
Mic

[photohoward1]

Hey Don... Ever had any luck or try rewinding Lehners? I have a couple of those. Would love to get a 3060 rewound. I burnt it up by Mistake.

[donhuff]

Thanks Mic.

I usually save "trash" for a year or 5, and if it doesn't move during that time, then I might throw it away.

[donhuff]

Howard,

Tyler sent be a box full of burned Lehners for me to tinker with. I took several apart, looking at how they go about doing their winds. I got it figured out but can't come up with a way of making the coils and getting them in the back iron and still have a correct hole for the stator. If I could see their process, I might could devise some fort of tooling to make it work.

I've recently purchased a 3d printer, and Lamar is getting pretty good at his CAD work. So I'm thinking of getting him to print me a very thin plastic stator, to use as a guide for the winding process. I've done that before with a 36mm ironless motor. It ran fine, but got smoking hot in about 2 seconds.

About the Lehners. I was very surprised to find such crappy wire inside of such an expensive motor! And when I say crappy, I mean the varnish insulation on the wire. It is thin and very low temp stuff.

[RaceMechaniX]

Don,

Regarding the Lehner's using low temp enamel, it is not the weakest link in their construction. Since the stator windings are bound by epoxy or varnish which will fail at 180DegC, there is no need to have a higher spec wire if the epoxy holding the wire fails first. The thinner enamel also allows more copper cross section and hence better current carrying capability and more copper instead of insulation. It's a trade-off.

Forming the windings on the Lehner is tricky, but it comes down to several key molds and tools plus some skill.

-Tyler

[jingalls007]

Hey Don, I have a 4070. I think I ran it 8-10 times in my RSX380. I’ll get a few pics when I get home.

[donhuff]

That about the epoxy, wire/enamel, makes good sense Tyler.

Is the slotless type actually "better"?

[donhuff]

jingalls, not just a tp 4070, but a 4070CM. They have different rotors in them that allows more RPM.

[jingalls007]

jingalls, not just a tp 4070, but a 4070CM. They have different rotors in them that allows more RPM.

I just realized you’re looking for the cm. Sorry about that. Mine is a regular 4070.