how to make it stay in ?

here is my bike and a close up of the front wheel .. i want to make a couple of alloy spikes that sit inside the axle holes one is round and the other is a hex ( hex on the right and round on the left ) .. see the drawing .. the problem is they are easy to make but i can't work out how to make them stay in ? i know i could make them a tight fit and tap them in but that's no good for a few reasons so is there a way to keep them in the holes ? nothing sticks out they will be sitting flush .. thanks guys ...

Edited By BASS 666 on 29/03/2022 16:24:45

Counterbore the spigot and bond in a strong magnet

Drill and tap the inside ends on both plugs and connect through the hollow axle with a piece of threaded rod.

Cross drill the round-side spike to take a small tommy bar to enable everything to be tightened down.

Edited By Bill Phinn on 29/03/2022 16:45:34

eyes on spike and spring thru spindle

internally thread spikes and have threaded rod thru spindle, sorry beaten to it

Edited By bernard towers on 29/03/2022 16:45:51

Anaerobics do not work as well on aluminium alloys as on steel, because of the oxygen in the oxide film, but ought to be worth a try, with an appropriate grade of Loctite..

If you wish to tap a fie thread in the bore, and a matching one on the bits, the increased area subject to the anaerobic would result in an increase the shear force required to move one relative to the other

Bearing in mind the different expansion rates for Aluminium compared to steel, you could try making the OD of the steel fitting an interference fit in the ally hub, probably 0.0005" .

Put the bits in the freezer for at least 24 hours, and then fit them immediately after removal.

If need be, as Plan B, make up a "puller" with a fine thread and use that to squeeze the bits into position.

If you adopt this, you could possibly increase the interference to 0.001" since that will increase the grip once the steel warms back ambient temperature.

The hope has to be that the heat generated by heavy braking does not soak through to the hub and release the new bits.

Howard

couple of really good ideas there .. thanks guys ...

A mechanical way of doing it is with sprung fingers:

The part that plugs in is turned slightly bigger than the axle socket, say +0.2mm, and the end chamfered for an easy start. The other end is of the plug is grooved down to under axle socket diameter.

The inner is bored out to thin down the gripping part so the fingers can give slightly when pushed into the axle. Finally, the fingers are made by slotting the plug part with a saw or angle grinder.

No need for special metal - most have enough inherent spring to grip the sides. How far oversize the diameter is and the wall thickness decide how tight the fit will be. Riding the bike will detach the thingy if made too slack. But don't make it so tight it has to be bashed in with a big hammer - it risks damaging the bike!

As corroded mechanical grips can be difficult to get off, probably worth providing a good grip for getting it off again! Perhaps slots for a pry-bar or a few holes for a hook.

Dave

If you put a cone on the inside and a screw to draw it in that should clamp them in well.

Hi All

Is the purpose of this to stop dirt getting in the hole? If so why not 3D print a plug that fits tigthly, also easy to replace if one gets lost.

I would be happy to do it if there is a good drawing

Regards, Martin

Also yacht grade 5200 sticks like the proverbial and should take any heat?

Might want to make them removable for MOT test, as sharp protrusions may not go down to well, bit like radiator mascots.

thanks Duffer for the trouble you went to .. Martin it is for looks only mate just to tidy up the look of the axles ....

Then put an alloy tube in the blunt end of each ‘spike’ … with a button magnet bonded-in.

Assuming you get the polarity right, they will be attracted

… if not, the spikes will self-eject

MichaelG.

Not at all, I'm luring you into the wonderful things you can do with your lovely lathe! Hooked on making this kind of work, you'll soon be selling the bike to pay for a milling machine...

Edited By SillyOldDuffer on 29/03/2022 20:47:58

Assuming the axle is hollow (has a hole all the way through) and the end caps or whatever are purely decorative then my suggestion would be to have an internal tension spring stretched between the (loose fit) caps to hold them in place.

To remove or install just ensure the spring has enough stretch so you can pull one cap out to access its hook.

Ian P

thanks again guys for the ideas i will post what iv done as soon as i get onto it ...

Unsprung weight is the enemy, so keep it lightweight!

Make some bungs from rubber.

Martin.