My Toyo ML1

Pete,

I got the reply from Axminster about the T-slot nut for SIEG C0. From your earlier posting, this seems to be just a waste, isn't it? Perhaps better to get it made.

the parts number 110.

Cheers

Just re-read that and wanted to say that I have no way, at the moment, to cut threads on this lathe, so I'll have to thread my propeller adapter collets manually with a die.

Hmm , no. Actually I will be forming the body of the collet and drill/reaming the centre bore, but not parting it off to the correct length immediately, so that I can turn it around and use the per-pated large diameter to hold on while die cutting the thread with the die holder backed up against the tool post for stability.

This is a prop adpter collet, the thread is M6 on this one. The 'top hat' thing has the matching 'female' taper to compress the collet and the split part of the collet will have a reamed internal bore to fit whatever motor shaft.

Sorry, just thinking out loud there.

That's the right part Oliver, but yes, it's pretty basic and will only take a few minutes to turn up from a short piece of 16mm bar.

If I was going to make a spare for my tool post, it would go like this.

Clamp bar in chuck.

Face off end,

Center drill to suit thread (M5)

Drill 4.2mm to approx 16mm deep

Start the M5 tap a few turns in by holding it in the drill chuck and gently turning the chucked workpiece by hand. (you have to leave the tailstock free to slide and apply light pressure towards the work) Use tapping grease.

Then release the tap from the drill chuck without disturbing it in the work. Slip a tap handle onto the tap and add a few more turns to the thread so that it can be finished later and will self align.

Remove the tap.

Turn the 10mm diameter

Form the 7mm 'waist'

Start the part off

Withdraw the part off tool and deburr sharp edges. BEWARE OF GETTING TOO CLOSE TO THE LATHE CHUCK WITH A HAND TOOL!!! IT WIIIIIIIILLLLLL BITE !!!!!!

Part off.

Form flats to clear inside your T slot..

.

Pete,

If I follow you correctly:

Rough it out, oversize, and cut the thread with your die.

Now put a bit of scrap in the chuck, and drill & tap M6 ... Don't remove it.

Run a nut up the M6 male thread; then screw it into the piece in the chuck, and use the nut to lock it.

Proceed to turn the part to size.

It won't be perfect, but it should be pretty darned good.

MichaelG.

Yes, the thread is not so important, because it doesn't specifically align the prop.

The critical areas of the prop adapter are the reamed bore for the motor shaft, the taper and the plain section and step before the thread. Those absolutely must be machined at the same time to maintain concentricity between the motor and alignment the propeller's own central bore.

It will be preferable for me to get the final saw slit prety central too. I may have to make up a similarly M6 threaded chunk of scrap to mount on the toolpost and run a fine circular saw in the lathe chuck.

Also, if I am forced to make my own female taper section, that will be critical too. Mind you, I'm using plastic propellers that are mostly injection molded. So I do have to pre-balance check them off the plane as well, then see if there's any vibration once mounted.

It's all fun in the end. If it's wrong, I launch the plane, the prop vibrates like all hell and then either the motor burns out, the speed controller fails, or the prop shatters.

Hehe! But seriously, it's never nromally that bad.

I recently had to knock up a different type of adapter at work due to my cheap Chinese one being visibly wobbly, and all is well now, with a vibration free flight .

Pete,

Thanks again for the detailed instruction. I guess I'll just show your message to him .

Well, when he's done that threading of course. I'm stil waiting..

At the moment just looking at other people shining object (propeller adapter collet).

Mind me asking again later when I need to.

Cheers