Narrowing Axles

[reliantman]

I saw your post about narrowing axles on the 100%Biker forum, and must say that you covered it very well.
I posted the drawing below on the Yahoo swedish trikes group a few years back after someone mentioned it. It is done the same way as you described, but with the added step of boring a small diametre hole in the centre of your shaft, and using a dowel to locate it while it is being welded.
Also, if you use a good piece of thick angle iron, 1 1/2 to 2 inches on a side to keep your shaft straight, fastened in with good g-clamps.

[Manky Monkey]

Hiya.
Yeah, if I have to butt weld two lengths of tube I usually lay them in a piece of angle iron to keep them more or less staright & true, (with a solid slug welded between them). Lots of variations on the sleeved joint aren't there. Comes down to which you have the facilities to produce & how confident you are of the results I guess.
Don't suppose you'd like to write a few paraagraphs on shortening a prop to go with that diagram?!
At some point I've got to offset the diff' on Rainbow's Suzuki trike to align the propshaft with the engine. I'll reword what I wrote on 100% & take some new photos. Narrowing just one side will be a good opportunity to show the standard & shortened versions.

[reliantman]

To be honest I only know about that trick because I did a bit of machineing while I was teaching kids to weld.

[Manky Monkey]

Sold Rainbow's trike as an unfinished project, (see the Motors, 3 wheels section), so here's what I posted on the 100% Biker forum about narrowing Reliant axles:

Step 1: Measure up your axle & decide how much you need to take out.
Step 2: If you've got any sense, forget it & bugger off to the pub. The propshaft's got 2 universal joints so will run at an angle of 30 degrees or so in any direction quite happily, though be careful if you're using suspension -all my trikes are hardtails. Makes life so much easier!
Step 3: Pull the drivehsaft out of the axle tube -easiest way is to leave the hub on & give the back of it a sharp crack with a lump of wood & a big ol' 'ammer.
Step 4: Drill out the 3 rivets holding the axle tube into the ally diff casing. The steel tubes are a sweated in fit, but it is possible to drive the tube out of the casing with a similar sized tubular drift & that hammer again. You risk cracking the casing though so much easier to take it to any competent car repair shop -is there such a thing? & give 'em a fiver to push the tube out with their hydraulic bench press, (like a glorified bottle jack in an upright framework).
Step 5: Note how far the tube goes into the casing, hacksaw off the required amount, (measure twice, offer it up, measure again, then go back & do it again just to make sure).
I think Reliant made their axles out of any old bit of scrap tube they found lying about cos very few of them are actually round. I was lucky with the Yam & it pushed straight back into the casing, but when I tried one last year I split the casing. Had to get a mate to put the cut-down tube in his lathe & spin it true for me -& find another casing. Replace the rivets with new bolts or rivets. If you use nuts & bolts make sure they're done up very tight. Use locking washers, threadlock & anything else you can think of cos you don't want a nut vibrating loose & bouncing around inside your axle!
Step 6: Cut the same amount out of the centre of the drive shaft -it's splined on the diff end & tapered on the wheel end so cut it in the middle. It's hardened steel so your B & Q hacksaw will just bounce off it. Use an angle grinder. Accuracy is nice but you've got a little bit of room for error cos the splined end which pushes into the diff gears can be moved in or out a little to compensate. Persuade someone with a lathe to machine you a mild steel sleeve, 2 if you're narrowing both sides -tubes of 4 or 5mm wall thickness that are a snug fit over the cut shaft, at least 2 or 3 inches long -the longer it is the greater your chances of the drive shaft running true afterwards.
Step 7: Slide the sleeve an equal distance over the cut ends & butt them together inside it. Get a competent welder to weld around the ends of the sleeves. When it's cooled down -hot welded steel STINGS! roll it along a surface you know is flat to check it's running true. If not, exchange words with your welder.
Some people leave it at that, but for extra peace of mind I drill both ends of the sleeve, all the way through sleeve & shaft & out the other side, drive in a steel pin, cut it off flush & weld over the ends.
Or forget it & go down the pub. 
Obviously the sleeves have to be a small enough diameter to clear the inside of the axle tube & obviously you need to check the direction of rotation of your propshaft if you're only narrowing one side, but XS750 Yams definitely need you to flip the axle over before you start. Not difficult, just take your time, think about what you're doing & double check all your measurements. If you're not sure of your welding capabilities get a qualified guy to do it for you & ask a responsible adult to do the cutting.
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[BikerGran]

Obviously this works, as you've done it before - but if you're only shortening one side, why doesn't that make it horribly unbalanced?

[Manky Monkey]

Good question Mrs B. No idea. Can't say I've ever noticed it if it is, but then I'm usually too busy hanging on for grim death!

[BikerGran]

Mine. as you know, is shortened one side, but it's butt-welded.

[Manky Monkey]

Ooh, you don't want to go welding your butt. I've welded my fingers a couple of times & that's painful enough.

[BikerGran]

I'm definitely going to learn to weld when I retire from my full-time job!  Always wanted to!

[Manky Monkey]

I'd recommend evening classes at your local tech' college.
Flap & I did a course of about a dozen lessons a couple of years ago. I'd owned a MIG welder before but just played with it till I thought I'd got it right. Was good to be shown where I was going wrong & to know that I'd got most of it right. 

[BikerGran]

There's a local agricultural college that does a selection of welding courses - from a opne day one for farmers, through various short ones right up to a full course with qualifications.

I reckon I'd do the one day to start with, to see if I wanted to do any more.

[reliantman]

Thats a good idea.
If you do a longer course, you might be able to take something in to make, like a frame maybe?

[Manky Monkey]

The guy who taught Flap & I was actually working as a Postie at the time so spent the whole course taking the mickey out of us -as most people do.
There was a girl who wanted to make garden sculptures, several renovating cars & one building a kit car. And us. We were told we were welcome to go back when future courses were being held to use the college's workshop facilities if we needed to. I'd imagine the lecturers would be pleased to have something a little unusual to work on.

[klogan45]

Hi Guys, butt welding, not plugging.....now theres a thought!!!!! Can't persuade the wife to play that though!!!!!!!
The bloke thats welding the trikes for me is also helping me to get things right. I weld a few bits of scrap ( I seem to have a lot of this) and he looks, laughs (a lot) and puts me right, I weld a few more butts...Eh BITS and he checks them out for me.
Good bloke, over thirty years experience. He sometimes works in the dockyard at Plymouth, welding boron etc. Is That good?
Take care, ride safe have fun.
Keith

[Manky Monkey]

Hiya Keith.
Getting your hands dirty's the best way to learn ain't it -welding, not butt plugging.
There's no substitute for experience -welding.