I received my "goodies" from RC Tank in Germany containing the HennTec Track Tension set and the (Manufacture ?) Axle Supports w/Bearings. I spent Thursday evening and yesterday getting them installed.
The Axle Support were first as they only required drilling the three mounting holes for each or so I thought.
The web site clearly states the they are for the HL 7.99mm Axles. I am using the Ultimate II Gear Boxes and when I tried to fit the supports they would not fit over the axle shafts. When I tried them on the stock HL Axle shafts they slide right on. When I measure them both with my dial caliper I found that there was a .01mm difference between them the Ulitimate set being larger, they are 8mm and when I measured before ordering I "thought" I had measured them the same.
MY Mistake!. So as a word of caution, be prepared if using the supports on a gear box other than the stock HL set.
Fortunately I have a Lathe and so I extracted the axle shafts and chucked them in the lathe and using "only" 400 and 600 grit wet/dry sand paper I polished them down until the bearings slip fit over the shaft. I then polished them out using 4000 - 12000 polishing pads. All Good Now!
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Next came the Track Tension system; drilling a 10mm hole using a drill bit NOT designed to drill plastic is a serious challenge. The bit wants to grab as the plastic is so much softer that the metal it is designed to drill. I almost let it get away on the first hole but stopped short of drilling through. I finished the hole by filling using a "rat tail" file. It was very time consuming but infinitely more controllable. For the second hole I marked out the diameter, then opened it up using a high speed cutter in my Dremel until about .020 undersized then filed it to size. All in all a straight forward installation just exerciser extreme caution if attempting to drill to full size.
Note; only applicable if you have the HL solid axle installed on you Idlers then the hole needed to locate the eccentric is too large (yes I know) you will have to reduce the hole size to match the eccentric shaft and center it to properly to locate the center of the 10mm bushing hole. You should then plug original hole though it is hidden behind the flange of the finished installation. The 10mm hole does overlap the original hole that is why I plugged it.
TAFN,
Barry
