Found New motor Is it any good?

[hyp7]

I got a Leeson Washguard design 90vdc motor.the tag states it is 90volts, 5amps, 2500rpm, will this work for a jennie mill? If im thinking right the rpm is to high. So is there a max rpm to not go over when looking for a motor?

thanks Hyp

[LarryDalooza]

I usually look for rpm/volts and look for the closest thing to 10... nothing over 25 for me... I have a 3000 rpm 130v (at 13 amps) which gets me to the number 23. which is 13v at 300 rpm... Still trying to better that.

Lar.

[kurt]

if its 90v motor and you want it for 12v charging you are looking for a 1750 to 1800 rpm motor to figure this out take the nameplate rpm divide that by the nameplate voltage then multiply by the voltage you want to cut in at like 12 or 24 volts you are looking for a number between 200 and 300 for most reasonable prop sizes for a 4' prop you could go as high as 350 if you make a fast prop for it but don't count on some crappy pvc blades doing the trick. larger the prop slower the cut in speed has to be.  

[hyp7]

thanks for the replys. I was going to make my own blades out of pvc. My Math says It will be around 361 rpms. Is that possible with certin blades?

thanks for the help

[ghurd]

Quite possible.  Not great, but possible.

Some of the Ameteks don't cut in until over 400RPMs, and there are a lot of guys fairly happy with the setup using 4' dia PVC.

I would try something more like 3' dia.

G-