Dummy Layshaft

[alan.barker]

In the title Dummy Layshaft.
Does anyone make or supply one.
Not the sort of thing you need often but a nice thing to have in the tool kit/gadgets.
Alan

[alanr]

Over the years I have just shortened an old layshaft which I guess is what most people use.
Alternatively when doing other manufacturer 'boxes that I haven't done before and will probably not be rebuilding again I have made them out of wooden dowel rod of almost the same size. It doesn't have to be absolutely perfect size.
Easy enough to make, just make sure it is long enough to just cover the rollers at each end but not too long because you need the thrust washers to stay in place when you refit the layshaft.
When refitting either just turn the box upside down to refit the layshaft or alternatively lift into position with a piece of string and then push the layshaft back in whichever you find the easiest.

Alan.

[alan.barker]

Thanks Alan,
I'll just wait for the delivery from TTR which includes new Layshaft. Before i cut the old Layshaft to use as Dummy. The old Layshaft looks in good condition but while it's apart fit new. Bearings, Seals, Thrusts, Tailshaft Bush.
Alan

[alanr]

Ahh..Thats easy then, just cut your old one down. You will have to grind through the case hardening first though before you can cut it with a hacksaw. Be careful though to wear eye protection when cutting, that case hardening can be dangerous as I know only too well!
I have a piece of Mk1 Cortina gearbox layshaft in my left eyelid that has been there dormant for the last 50years, thankfully though it didn't go through to the eyeball and my eyesight is still ok!

Alan

[SENC]

I've just used a wooden or brass dowel. Take a quick measurement of the (skinny end of the) layshaft. I don't remember that offhand, but you should be able to find a wooden or nylon or delrin dowel the same size or a shade under. Though I haven't used the cut-down layshaft method, I think having a longer dummy with a touch looser fit makes the job easier.

[promotor]

In the title Dummy Layshaft.
Does anyone make or supply one.
Not the sort of thing you need often but a nice thing to have in the tool kit/gadgets.
Alan

Alan,

Use an old layshaft cut down. You will need to take the O/D of the dummy shaft down so that the dummy shaft can come through the front of the gearbox when installing the new layshaft - if you leave it the same O/D as the original it will be too tight when passing through the gearbox casing at the front as this is usually interference fit. Also, don't forget that there is a small portion of the layshaft at the rear that is a few thou larger than the majority of the shaft to give interference fit at the back aswell - this should be part of the shaft you definitely don't want to leave at that size.

[alan.barker]

Cheers boys,
Looks like i've got a job to do tomorrow wearing my saftey goggles.
Alan

[2cams70]

The method of using grease to stick the thrust washers and rollers in place and lifting the laygear using a piece of string at either end or turning the box upside down works well I’ve found. I use it in preference to a dummy shaft

[seniorchristo]

I've used a 5/8" wooden dowel purchased locally. It is very slightly undersize but works fine.

[alan.barker]

Many thanks for the ideas boys,
i've found a bit of steel tube a little smaller in dia than the Layshaft. Looks like it will do the job nicely.
Just waiting for parts to arrive.
Alan