[MattsAwesomeStuff]

For couplers, most big cities have at least one transmission/driveshaft shop that has everything you can imagine. If your first guess is wrong, ask them who you should call.

Give them the precise measurements and they'll flip through their inventory and see what's available.

Option 2 is to try tractor supply places. Generally larger stuff.

 

[Duncan]

Re - female splines

My motor (s) have a brake drum on the front of the motor - used as a handbrake I believe in the forklift

That has a nice internal spline to match the external spline and four studs for the brake drum
It's very easy to modify to adapt to a driveshaft

It may be worth contacting forklift repair shops and trying to get one

 

[tomrock]

Thank you for your replies. I have taken a gamble on a splined driveshaft coupling online (£9) that measures correctly as far as I can tell. I will report back once it arrives.

I think both of you are right - for the coupling I will be best taking it to someone knowledgeable with lots of parts to hand. There are plenty of agricultural companies near me that would be worth giving a go.

 

[skweeks_n_leeks]

I am in a similar situation. I plan on having the splines machined and a yoke/coupling of some sort with a bearing added. Figured I’d have the same shop turn and clean up everything else as well.

 

[tomrock]

TLDR: Land Rover flange fits Caterpillar motor

Great news! The drive flange I bought fits! It is a drive flange used on many Land Rover cars (Defender, Disco, Range) and so there are loads of varieties with the same spline meaning many options for a starting point to machine my coupling.

The fit is clearly not a coincidence, and must follow a common spline standard. The spline profiles mesh well and there is only very small amount of backlash, as you would expect for compatible splines.

This is the exact flange I have tested, although a quick search has brought up at least 5 similar components with the same spline:

https://www.ebay.co.uk/itm/24-Spline-Drive-Flange-for-Land-Rover-Defender-FTC859R-RUC105200-Bearmach/232625320648?epid=1642542757&hash=item36298cb2c8:g:bY0AAOSwjytaVSR4

This is very useful for me and I am sure could be useful information for other DIYers.

Re: skweeks_n_leeks

Taking it to a machine shop sounds like a good idea. A bearing support would be particularly valuable if the gearbox (?) you are going using requires end support. Edit: I have just read your thread "Motor A or B?". Looks like a good motor.

 

[MattsAwesomeStuff]

Hurray! A success.

You're way ahead of me now, with my unobtanium spline profile.