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Looking for top shaft diemnsions

Posted: Fri Feb 12, 2021 10:45 am
by adam lancia
Would one of you kind souls measure the dimensions of a slipper or Hydradrive top shaft that has the top gear keyed to a roll pin, please and thank you...?! It's for a secret project that may or may not include mutting up a Lethal Weapon for an even more mutted up Ultima Pro XL :mrgreen: 8)

I'm really curious about the distance from the roll pin to the end of the shaft, how far from that end of the shaft the slipper hub flats are. Also, I think there's a circlip groove, that would be good to know too.

Thanks in advance!!!

Re: Looking for top shaft diemnsions

Posted: Mon Feb 15, 2021 2:27 pm
by matt1ptkn
Is this for the LRM transmission or XX/retrofit transmission?

Re: Looking for top shaft diemnsions

Posted: Tue Feb 16, 2021 5:52 am
by adam lancia
matt1ptkn wrote: Mon Feb 15, 2021 2:27 pm Is this for the LRM transmission or XX/retrofit transmission?
Both would be nice actually if possible.

Re: Looking for top shaft diemnsions

Posted: Tue Feb 16, 2021 6:34 pm
by mikesofunny
This is a XXT CR Hydradrive shaft

Edge of pin to outer end of shaft
20210216_172400.jpg
End of shaft to flat
20210216_172453.jpg
Inner end of shaft to flat
20210216_172540.jpg
Edge of E-clip groove to flat
20210216_172702.jpg
Hope this helps

Re: Looking for top shaft diemnsions

Posted: Wed Feb 17, 2021 6:01 am
by adam lancia
That's a big help, thanks!

Re: Looking for top shaft diemnsions

Posted: Wed Feb 17, 2021 8:38 am
by Johanp
Even measured in millimeters! 8)
Can you also please measure across the D section?
Thanks!

Re: Looking for top shaft diemnsions

Posted: Wed Feb 17, 2021 1:55 pm
by mikesofunny
Johanp wrote: Wed Feb 17, 2021 8:38 am Even measured in millimeters! 8)
Can you also please measure across the D section?
Thanks!
Even though the old stuff is standard, we all know it's easier in metric. :mrgreen:

You want to know the diameter of the flats? (It is flat on both sides of the shaft, not just one)

Re: Looking for top shaft diemnsions

Posted: Wed Feb 17, 2021 8:34 pm
by mikesofunny
Wasn't sure if you were looking for length of the flat section, or diameter of the flats, so here's both.
20210217_192638.jpg
20210217_192734.jpg
And of course the shaft is 3/16"

Re: Looking for top shaft diemnsions

Posted: Wed Feb 17, 2021 11:15 pm
by Johanp
My bad. Forgot it was flat on both sides and not D shaped.
It was the 3,2 measurement i was loking for. 1/8" i guess... :wink:

I have most parts for a XX slipper as spares in my old box of rc stuff. Would like to fit it to a LRM transmission but is missing the top shaft. Thinking of having one made. So this thread is very helpful.

Thanks!

Re: Looking for top shaft diemnsions

Posted: Wed Feb 17, 2021 11:57 pm
by mikesofunny
Johanp wrote: Wed Feb 17, 2021 11:15 pm My bad. Forgot it was flat on both sides and not D shaped.
It was the 3,2 measurement i was loking for. 1/8" i guess... :wink:

I have most parts for a XX slipper as spares in my old box of rc stuff. Would like to fit it to a LRM transmission but is missing the top shaft. Thinking of having one made. So this thread is very helpful.

Thanks!
I installed a XX Double-disc slipper (could also do single disc/hydradrive, whatever) on one of my LRMs, no mod needed, just used XX stuff I had laying around. Now I know the early ones weren't slipper at all, but the later ones (like this one) were made for the slipper. You just need a Losi A3120 top shaft... if you can find one.
20210217_224658.jpg

Re: Looking for top shaft diemnsions

Posted: Thu Feb 18, 2021 12:37 am
by Johanp
mikesofunny wrote: Wed Feb 17, 2021 11:57 pm
You just need a Losi A3120 top shaft... if you can find one.
Yes... :D

Both my LRM:s are non slipper.
The idea is to use your measurements in combination with measurements taken from my non slipper shaft and see if I can get one of my machinist friends to make one. It might cost me a couple of beers. :wink:

Thanks for your help!

Re: Looking for top shaft diemnsions

Posted: Thu Feb 18, 2021 12:43 am
by Johanp
adam lancia wrote: Fri Feb 12, 2021 10:45 am It's for a secret project that may or may not include mutting up a Lethal Weapon for an even more mutted up Ultima Pro XL :mrgreen: 8)
Sorry adam lancia for stealing your thread!

It sounds very interesting using a Lethal Weapon in an Ultima with a Losi slipper. 8)
Keep us updated!

Re: Looking for top shaft diemnsions

Posted: Thu Feb 18, 2021 5:37 am
by adam lancia
No apology necessary! Good luck with your project.

mikesofunny, thanks for the extra measurements!

Re: Looking for top shaft diemnsions

Posted: Thu Feb 18, 2021 6:35 am
by matt1ptkn
Here are the dimensions for the LRM Hydradrive/slipper top shaft.

Re: Looking for top shaft diemnsions

Posted: Thu Feb 18, 2021 9:21 am
by Johanp
Thank you both for taking the time to take measurements!

Now in my CAD:
shaft.JPG