Fitting freewheels to splined freehub drivers

Miles

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Ref: http://www.endless-sphere.com/forums/viewtopic.php?f=28&t=12267&start=146
liveforphysics said:
I'm going to buy the sic bikes eno freewheel, and a regular freewheel, and the dual-drive hub, and make the freewheels fit on the splines by hand with a file. I will make a jig using sprockets clamped to the freewheel's inner portion, and carefully work it with a file until they slide on the splines.
3-spd motor drive, 3-spd pedal drive, no derailer BS, no needle sprauge clutch BS, and completely independant drive isolation.
liveforphysics said:
And if it doesn't seem like there is adquate room for both to fit onto the short splines of the dual-drive (likely), then I will shave down material from the freewheels until they are thin enough to both fit. If they still don't both fit, I will take the dual drive hub spined portion off, and figure out what it will involve to get the required length spline portion mounted. Likely would involve machining some custom shift rod pieces at the very least, but I'm game for a few challenges.
Miles said:
BTW, the 9 speed splined driver is exactly the same length as 2 freewheels, so no problem there.
Miles said:
If the number of engagement points on the freewheel has a factor of 9, you can use the freewheel mech. to register the spline positions for filing. Then, all you need is a guided file slightly wider than the driver splines. :D

moderator edit: here is Thuds freewheel spline ctutting thread:

http://www.endless-sphere.com/forums/viewtopic.php?f=28&t=37640&p=548136&
 
Tracking numbers indicate a Wednesday delivery of the freewheels. It's going to be fun to put the splines in them :) I've got the perfect file for the job.

I've got a pretty good tool to open up that inside over hanging lip the required amount as well, but I can always throw it on the lathe if it doesn't work as well as I hope.

This will open the door for a new level of no-compromise RC builds, and improve simplicity and reliability. The performance with the 3-spd hub coupled with very high power motors should be a shocker :) Unlimited slope effortless hill climbing. 70+mph top speeds. Ultra efficiency, and acceleration that will beat every electric bicycle AND motorcycle on this forum :)
 
I have a spare ENO freewheel, so I might have a go at this, too :)

Although fitting the ENO is more trouble, you end up with a better contact area. There's not much engagement when the splines are cut into a standard thread.....

I'm relying on you to find the torque handling capability of the Dual-Drive hub, Luke :mrgreen:
 
The other possibility, for the outside freewheel, is to lock it using the internal thread on the driver. I'm not sure that would be strong enough, though.....
 
I like splines better than threads when it comes to holding torque.

I'm gona hit that dual-drive hub with a house, and it holds, then we know it's got what it takes :) If it grenades, I'm gonna mail it back and tell them to show the RnD guys where the weak links are, and what they can do about it.
 
as long as you have a lathe, means you likely have a bench grinder.

1. grind a single tooth cutter the dimension of the slot. mount it to the tool post so that it cuts in the "X" axis. that would be like 90 deg to normal with the cutting edge facing you.
2. chuck up the part that you want to cut the splines into.
3. now you can adjust the depth of the cut using the "X" cross-slide.
4. stroke it like a broach using the "z" logitudinal travel.
5. index the splines by rotating the chuck by hand. you can use the teeth of the driving gears/sprocket on the back of the lathe to measure your index angle.

keep the cuts shallow .002 or so. the lathe is not under power during this operation.

rick
 
LFP.
When its time to lace a wheel with the power your talking about, this is the place I get my spokes from.
http://www.buchananspokes.net/products/individual_stainless_steel_spokes.asp
been using them since 78'
 
You could drill a few mounting holes in the handle of the file and mount it
onto a reciprocating saw or sawzall. Now you have a high speed file to broach with.
Maybe too fast.. You also may have to remove the tempering from the
handle to drill it unless you use carbide.

$0.02
 
Actually, there's not all that much material to remove. The inside part of the ENO freewheel isn't particularly hard - it's only the outer part, with the ratchet teeth, that is hardened.
 
Hi,
liveforphysics said:
.... no derailer BS, no needle sprauge clutch BS, and completely independent drive isolation.
I think the ability to use a White FW with #219 is an equally big advantage.

Miles said:
Miles
I'm relying on you to find the torque handling capability of the Dual-Drive hub, Luke :mrgreen:
We're definitely going to learn the abuse tolerance of the Dual-Drive hub. Torque handling capability probably not :p.

Miles said:
Actually, there's not all that much material to remove. The inside part of the ENO freewheel isn't particularly hard - it's only the outer part, with the ratchet teeth, that is case-hardened.
That sounds doable. I was on a video shoot in Bombay and we some locked expensive equipment in two steel lockers. I used a Master Combination lock and my friend used a Keyed padlock made in India. He lost the key and used the Saw Blade on a Swiss Army Knife and cut through the shaft very quickly (teeth designed for cutting wood!). I had him try it on the Master lock and when he gave up there was a barely perceptible scratch. :lol:

Gary said:
If it works, it will definitely beat having to pay for a quantity of 100 to get Doug White to do it. :roll:
If anyone thinks its worthwhile I'd be happy to contact dgcustommachining and ask if he'd modify stock White FW's and if so what he'd charge.

I'd also be happy to contact Sickbikes. I'm not sure there's a big enough market to make it worth their while but if there is they would probably willing to have them made by White. The price to us would be more than going directly through White.

12p3phPMDC said:
You could drill a few mounting holes in the handle of the file and mount it
onto a reciprocating saw or sawzall. Now you have a high speed file to broach with.
Maybe too fast..
Variable speed.
 
MitchJi said:
I'd also be happy to contact Sickbikes. I'm not sure there's a big enough market to make it worth their while but if there is they would probably willing to have them made by White. The price to us would be more than going directly through White.
I don't see any advantage in that. This is our project.
 
I wonder how much a custom broach would cost?

$1000??
 
plus you would need a broach actuator....

I haven't been around large shops with this capability...
but I can see a Z axis CNC plunging the broach
into the bore using a handful of passes.

$2000 is not cheap but it would be cool.
 
I'm not real familiar with machining techniques but could a waterjet cut the slots?

$2000!!!??? Holy Canoli!!! Seems like you could get raw material made into the desired shape for less.

I'm surprised the guys from the motored bike forums haven't jumped on this before us, it seems like the next logical step for more speed and torque. But if someone does come up with an affordable solution, it seems like a dual market for the attachment.

Also, has anybody suggested melting that alumaweld rod around the freewheel and the splines? Maybe practice on a cheap rear hub and freewheel to see if it works? You might have to do multiple passes, but if you pool it around the freewheel indentations it might hold up pretty good. Or would this ruin or warp the dual drive? Telle if this has been discussed. :?
 
12p3phPMDC said:
plus you would need a broach actuator....

I haven't been around large shops with this capability...
but I can see a Z axis CNC plunging the broach
into the bore using a handful of passes.

$2000 is not cheap but it would be cool.

there is little enough material to remove. the broach could be pushed through using an arbor press.

what i was suggesting earlier was to use the lathe as a broach of sorts. wouldn't use it for production, but to make one or two pieces it would be fine. i have used this technique to cut keyways. an aquaintance used it to make a rough gear.

rick
 
rkosiorek said:
there is little enough material to remove.

Too right! I'm not sure it's going to be enough having splines cut solely into a standard thread....

Here are the measurements:

SRAM Dual-Drive freehub driver
Major diameter of splines 34.35mm
Minor diameter of splines 32.2mm

ENO freewheel
Inside diameter of threads 34mm

I milled the "neck" of my ENO freewheel out to 32.5mm
 
etard said:
Also, has anybody suggested melting that alumaweld rod around the freewheel and the splines? Maybe practice on a cheap rear hub and freewheel to see if it works? You might have to do multiple passes, but if you pool it around the freewheel indentations it might hold up pretty good. Or would this ruin or warp the dual drive? Telle if this has been discussed. :?
Might be good to add some metal to the ID... flowing bronze into the threads before cutting the splines might help. I doubt the alloy brazing-rod could bond to the steel.
 
My two cents on how to do this would be to use several old freewheel drivers as EDM tools to machine out a matching bore. Alternatively a cassette cog or two could be made into an OD broach to make an EDM tool out of copper bar. Alternatively if the core of the freewheel is fairly soft, grinding up a custom tool and using a Shaper or Shaper attachment and a rotary table works well too. (a shaper attachment looks like THIS) Of course a file is fine too, I'm just not that patient. :roll:

Lawson
 
Unless I think of a better idea, I'm going to take the nut out of my lathe toolpost slide and use the slide as a guide for the file - with the file clamped in the toolpost and the freewheel inner in the chuck. I don't think my lathe is rigid enough to use as a broaching machine.....
 
http://www.markwilliams.com/broaching.aspx

Broaching at
$8 per piece for 20 piece lots??

that's cheap...

I think one of their processes uses Ricks method on a CNC lathe.
 
Just Google "Broaching Services" for your local.

http://www.vwbroaching.com/specialty_broaching_operations.php

Wire EDM ??

http://www.vwbroaching.com/wire_edm.php#wire-edm
 
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