Hub / Hex Slop elimination 17mm techniques - FAQ
[QUOTE=pavmentsurfer;5180600]There was a thread about this idea a while ago but I haven't yet seen anyone actually do it. My ERBE had some slop in the hexs so I figured since I had a spare set I might as well try cutting them down and seeing if it works. Heres what I did.
I cut the threads off the stock 17mm adapters leaving only the hex. I used a battery powered sawzall and the cut was actually pretty good. Pretty clean. Heres a pic of a newish set of hexs on the left and my cut hexs on the right:
The next step is to use some sort of cone file (or in my case a cone bit on a dremel) to clean up the cut end of the axle hole. If there are ANY burrs the hexs wont slide back over the stock axles. I learned this the hard way:
Then, of course, re-install the hex using the stock screw pin. Nothing special about this except the threaded end of the adapter is missing:
Lastly, install your wheels (with this mod you can use standard 17mm wheels OR traxxas style 17mm wheels) using the nut from the HPI 17mm hex set:
The results of this mod is nearly ZERO slop. After the install is done any looseness in the adapters is gone and the wheel is tight on the axle. Total cost, about $10 for the HPI 17mm hexs and nuts but you could probably get JUST the nuts for less if you look around online. Total time for mod, about 20 minutes with some good power tools.
There are lots of other options out there. But since anyone wanting these type of results likely already has a worn out set of stock 17mm adapters you might as well try it. You have nothing to loose.[/QUOTE]
[QUOTE=ksb51rl;5485377]I much prefer an elegant insertion of a stainless steel helicoil to
hacking up a part that is 99 & 44/100 good. It takes a bit more work, but you are left with
an essentially unchanged Traxxas part.
[QUOTE=BRICK57;5486306]Can you elaborate on the Stainless steel heilicoil. did you insert it or did you buy it that way.[/QUOTE]
[QUOTE=ksb51rl;5486585]I think first I'd like to say that there is definitely a place for pav's method. It is cheap, effective, and relatively easy. There is NOTHING wrong with it, but we're all allowed to have our preferences.
I made the one in the video and a few others like it. The hubs were wobbly enough that the axle threads had cut into the outer part of the axle hole, even though they are not supposed to touch.
I used a drill press and a home-made jig to drill the center holes to 13/64", which is the correct size for installing M5 helicoils or permacoils (same thing.) The drilling takes off a very small amount of aluminum. You then need an M5 helicoil/permacoil tap to cut threads in the aluminum hub. I did this by hand. You then need the M5 coil installation tool to screw in the stainless steel coil (I used a 7.5mm length) and a small punch to knock off the coil's tang. Screw the hub with coil onto the axle and insert the stock grub pin because now you're done.
Now here's a BIG "However":
It is possible but not likely that the grub hole in the hub will not line up well enough with the hole in the axle for the pin to go through. There is no control for this with the limited tooling I possess. I will say this though: if a hub will not work on a particular axle, in my experience it will always work on one of the other three.
There you go: more than you wanted or needed to know. :)[/QUOTE]
just some FAQ fodder:)