Shortening a jackshaft

I had a Simca Aronde for a bush basher when I was 15 - it had something like that.

Jarrod.

Been doing a bit of research into driveline angles and uni joint selection into this topic. If I go the way of common Spicer 1310 and 1350 components, can get the centreline to centreline (of uni's) down to either 6.4" or 8.0" length,using the shortest female slip yoke and shortest male stub available in 16 spline. Still has to be balanced though even using two common Spicer parts.
They (Spicer) give the MAX angles of 8* and 20* respectively, but don't tell you if that is actual difference between parallel faces of both yokes, or the inclination of the driveline angle or slope. (Been posted here on this topic that you want at least a bit of angle to ensure long life out of the uni's, going by postings on some forums, at least 3* is ideal, again doesn't say if that is face to face or inclination).
As this has to be set up in the chassis from scratch, can build accordingly, probably 8" maximum length of jackshaft would be ideal to keep away from the chassis crossmember just behind the cab. Rear propeller shaft not a problem as can be shortened at any time and to any length, again I have most of the components here, just need a conversion universal joint, also readily available in different sized caps as well as mixture of internal/external circlips. One thing I am having a bit of grief obtaining is the universal saddlecaps to suit a Dodge 1310 internal circlip joint, the ones that take the 1/4 UNF small headed bolt. Can get away with the bolts using Allen head socket capscrews, but need at least two saddles.
Dave_64

Dave64
Try I Know parts at Guildford military road nsw
Try and speak to Paul ( sometimes hard to get him)
They seem to be able to get those hard to find bits
Cheers Diggerdave

Had a bit of an unexpected win, around at a mates place and he was readying stuff to go for scrap when I noticed an old NP gearbox with the output yoke still on the back. Hastily removed the saddles before he changed his mind. Do have a rare win occasionally!
Dave

A lot of earlier trucks like little Commers,Karriers,Austins had rubber bushed universals in the tailshaft.Often a joint called a "Layrub".They are still available,but expensive.I have shortened many shafts,and never had one balanced.If you restrict yourself to the male spline end,its easy to get it all straight,and to turn the weld to an even profile.The pro shaft shops use balancing to hide runout in the job,and strip you of another $100.

John K,
Can buy from Spicer what they call a short coupling which consists of both the male and female components, so no actual tube involved. Allup length either 6 1/2" or 8". will take standard 1310 and 1350 series or combinations of both with internal and/or circlips. I was hoping to use up a few old, but serviceable components I have here. Uni-joints are not the problem, can get those, probably got enough to do the job.
Have been told that even using a std male/female coupling will still have to be balanced, like you I'm wondering just why. Would think that as long as I have the uni joints and splines (common 16 spline) lined up correctly and don't exceed the published angles unless the stub ends have NOT been pre-balanced.
Dave

Like This, gives two different MAX angles for two different lengths,
Is that measured between the two faces OR the MAXIMUM inclination (or slope)
of the shaft??

Dave

Hi Dave. I would think that the maximum angle is between the face of the flange and the shaft. I would try and set it up so your flange faces are parallel.

I agree with JohnK on balancing, if setup and welded properly than there is not normally a problem. I have done a couple that have turned up near 5000rpm. I am not saying don't balance,
I never have. I have heard the horror stories and all have been on shafts assembled by "professionals".

I have welded blank 16" rims onto used AU centres, stretched by hammer on anvil to fit. I did set the rims up true with dial indicator, then tacked and stitch welded. The tyre fitters said they ran truer and better balanced than commercial Sunraysia copy wheels.

If I was building a short small diameter jack shaft for hobby use age, I probably would not have it balanced.
Paul

paulc20 wrote: Hi Dave. I would think that the maximum angle is between the face of the flange and the shaft. I would try and set it up so your flange faces are parallel.

I agree with JohnK on balancing, if setup and welded properly than there is not normally a problem. I have done a couple that have turned up near 5000rpm. I am not saying don't balance,
I never have. I have heard the horror stories and all have been on shafts assembled by "professionals".

I have welded blank 16" rims onto used AU centres, stretched by hammer on anvil to fit. I did set the rims up true with dial indicator, then tacked and stitch welded. The tyre fitters said they ran truer and better balanced than commercial Sunraysia copy wheels.

If I was building a short small diameter jack shaft for hobby use age, I probably would not have it balanced.
Paul

I have also done a the odd shaft and fair few rims and dont even use a dial indicator on the rims and have never had a problem
The shaft place I mentioned earlier the shafts I got done there never cam back with weights welded on, I watched him doing a shaft for me once and he heated it in spots with a oxy and put water here and there and I guess pulled any minute bends out of the shaft And I have never had a problem with any of the shafts that fella did never done uni or anything yet other shafts from the factory always seem to be getting crook unis
So maybe the person doing it makes a huge difference as well

Paul

Dave_64 wrote: Like This, gives two different MAX angles for two different lengths,
Is that measured between the two faces OR the MAXIMUM inclination (or slope)
of the shaft??

Dave