"Found an awesome torque arm" (3 pages)
viewtopic.php?f=1&t=11570
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Original thread died. Figured I'd help out and repost what I saved.














Here is the album link: http://imgur.com/a/ff1DI
It was only AUD $45. It's mild steel, which i'm assured is strong enough, but it will rust. The black paint it rustproof.auraslip wrote:Very nice! How much did they charge you?
That'd be easier,cheaper, and work just as well. You could even stack some washers in between the shaft and the plate to solve clearance issues.Re the above, I'd rather have two bolts than the spline. Customer would drill holes and bolt to his angle, or just weld it.
This probably just means the steel you use wasn't hard enough. Heat treatment or using a different allow would prevent the shaft from biting into the torque arm. As mild steel is a bit too soft for an application like this. The proper material could increase the lifespan by a factor or two.John in CR wrote:Anyone who thinks their torque arms are sufficient should consider this. After almost 2.5 years my dropouts, which are 1/2" thick steel each side with a snug tap in fit to the axle, recently developed a hint of play due to 9 months of regen braking.
John, it seems like you are the resident expert for using high powered hubs safely and reliably. If you say clamping torque arms are the only option, I will believe you and start planning a clamping torque arm design on my next bike. I know you've covered it hundreds of time by now, so I feel bad suggesting it, but you should consider doing a FAQ on making them for everyone else.Many of the motor axles are pretty soft too, so hard steel in the torque arm or dropouts may not help. Thickness for more contact area is what matters, and if you have regen, you better have a clamping type.
Just because I harp on something doesn't make me an expert, but I do make sure my hubmotor wheel can't fall off. I make torque dropouts, not add-on torque arms, but the concept is the same. Here are some pic. Some are 5/8" per side and some 9/16" per side:auraslip wrote:That derailluer hanger looks like butter compared to my 1/4" steel torque plate of approximently the same size that only lasted half a mile.
John, it seems like you are the resident expert for using high powered hubs safely and reliably. If you say clamping torque arms are the only option, I will believe you and start planning a clamping torque arm design on my next bike. I know you've covered it hundreds of time by now, so I feel bad suggesting it, but you should consider doing a FAQ on making them for everyone else.Many of the motor axles are pretty soft too, so hard steel in the torque arm or dropouts may not help. Thickness for more contact area is what matters, and if you have regen, you better have a clamping type.
That axle in the curved torque arm appears to be smaller than 10mm. The 10mm axles I have are a very tight fit in those arms, needing to be tapped on in some cases.John in CR wrote:...
Here's one of my clamping type next to what at first glance seems like a nice thick through hole type torque arm until you see that the axle is about to spin even before the motor is turned on. ....
Yes of course. I've done them both ways, and always use the blue loctite either way. The experienced metal working guys can make something pretty and 100% effective quite easily, but with just a hacksaw, drill and angle grinder an inexperienced guy can do something absolutely effective too.auraslip wrote:Thanks John. I think you won this thread![]()
Figuring out how to make this for a reasonably experienced guy should be cake.
One question though: Do you think It'd be acceptable to drill the bolt hole all the way through and secure the bolt with a nut on the other end? A good tap and die set can be.... expensive.