Replacing outrunner shaft

[flanders]

Would it be possible to replace an 8mm 5065 outrunner shaft with a steel threaded bar? the sprocket I have has a D shape hole and I was thinking I could just grind a little off to bolt the sprocket on?

or maybe use a part threaded bolt? would I need to cut a ring for a cir-clip to hold it in place, or is there a better way?

I know the easiest way would be to buy a sprocket with set screws? only trouble is I want to keep the 1/4" chain and rear sprocket, and I am having no luck sourcing a 1/4" sprocket in the UK.

 

[gwhy!1]

Would it be possible to replace an 8mm 5065 outrunner shaft with a steel threaded bar? the sprocket I have has a D shape hole and I was thinking I could just grind a little off to bolt the sprocket on?

or maybe use a part threaded bolt? would I need to cut a ring for a cir-clip to hold it in place, or is there a better way?

I know the easiest way would be to buy a sprocket with set screws? only trouble is I want to keep the 1/4" chain and rear sprocket, and I am having no luck sourcing a 1/4" sprocket in the UK.

You can get them from 1/4 sprockets from technobots

 

[flanders]

technobots don't do 1/4" (6.35) sprockets, they do 6mm but don't think these will work with a 1/4" (6.35) chain?

 

[gwhy!1]

sorry I assumed that you were referring to standard bicycle chain sizes

 

[bandaro]

In my experience, don't even bother. Places like electricscooterparts.com, surpluscentre.com and others are all over the web, so you should be able to find a type b (with hub and screws) locally. I think modifying the motor is a bad idea, the 63-74 motor that I had had the shaft press fitted and set screwed into the can, so removing it destroyed the press fit, so my new shaft never sat straight.

Also, the shaft is not hardened on the motors (turnigy/leader rc ones) so if that is the motor you have, then the D will rotate around relatively quickly. It may be cheaper in the short run to try to fit the sprocket you have, but I would strongly recommend getting a type b hub. With set screws, you can easily replace the sprockets or take them on/off.

Lastly, be aware that the smaller the sprocket the noisier it will be, especially at high speeds, so if it a 11 tooth, it will be rather noisy at motor speed.

 

[spinningmagnets]

Start scrolling through the non-hub resources thread (link included below). Wood routers use bits that have an 8mm shaft and also a 10mm shaft. Local router suppliers (and web-stores) have bushings that snugly slide over an 8mm shaft to make it 10mm, which would increase your pulley/sprocket options.

Its been my experience that these RC shafts are easy to work, so you could file a flat onto its side, then drill a dimple for a grub-screw?

http://www.endless-sphere.com/forums/viewtopic.php?f=28&t=7192&start=30#p311888

 

[flanders]

well I have filed down the shaft and fitted the the sprocket with the D shape hole, although as you say bandaro the shaft is not hardened so not sure how long it will last but will give it a try

I have managed to find some #25 sprockets at surplus center that will ship to the UK, at a reasonable cost, only trouble is they are not hardened? is it worth trying a 11t or will it not last 5 mins?

 

[gwhy!1]

#25 small sprockets 11/12/13t can be got from here 'D' but Im pretty sure they are for a 10mm shaft tho. http://www.osetbikes.com/en/parts/drivetrain

 

[flanders]

thanks gwhy, but I am after the type with the set screw, I think these D ones are not going to last long on a soft outrunner shaft?

 

[gwhy!1]

thanks gwhy, but I am after the type with the set screw, I think these D ones are not going to last long on a soft outrunner shaft?

personally I dont think there will any problem with a 'D' on the 8mm shaft, I have used 'D' on the 10mm shafts and these have been fine as long as there is no rocking movement (play).

 

[RWP]

I have no experience with D ring shaft attachments.
But can say from experience that expecting grub screws to work on a flat shaft surface is doomed to fail. What was suggested is to dimple the flat to allow the grub screw to have a nesting place works.
What I have been doing successfully is to forget the flat and go right to the dimple. Works like a charm.
I use two grub/set screws at 90 degrees.
Just drill out the flat in the sprocket or pulley to make it fit the shaft and add the dimples.