Old Open Armatures

[eap9]

Hello Monty!

I have some new old stock hand wound open armatures from Bob Green and John Cukkras. They are c-can length with .513 stack diameter.

Were they set-up in a c-can with ceramic magnets before? Will they perform much faster than a grp 12 motor? The Bob Green arm is a single 26 and the Cukkras arm is a 26/28 double.

Thanks.

Enrico

[Monty @ B.O.W.]

Enrico,
Yes, the old pro motors from the early 70's and late 60's were ceramic magnets, and yes, those arms should offer more brute power (although maybe not as much RPM - lower timing!) than a Gr.12. The only reason they don't blow up almost immediately is that lower timing!

[Phil I.]

:) Those guys were screamers in their day! Remember the OLD days were weak magnet and lousy comm days that would throw apart when they got hot! Find a setup that had LOTS of arm clearence and weak mags. They mite live this way but be carefull and check for heat! I had an old Cukkras double 29 that I ran on power pack tracks in the late 60's.It was in a Mura setup and ran good for what it was. I put it in a Slotworks setup with Mura Red Dots and it got so hot it started to slow down.:)
Good Luck,
PHIL I.

[Slotracer152]

you guys are old :D

[eap9]

I tried it on a proslot topgun set-up and the arm fit perfectly well. Should I use medium tension springs and what was the normal gearing then 10/39?

[Foamy]

8/43 with 13/16 tires used then.

[eap9]

Wow do they really scream! I tried it using 8/39 gears and .740 diameter tires and was surprised at the rate of acceleration. It was a brute likw a 427 AC Cobra - very hard to control. Nothing smooth here just raw power.

[MarcusPHagen]

but I remember using 7:35 (48-pitch) with 7/8" rear tires in 1970.

mph