Does anyone have a tutorial on how to take advantage of the hinge casing of the 5990TG when mounting it to an ASB-04? I also would like to know what kind of reamer to use to enlarge out the hole on the ASB-04 since most reamers I found in hobby shops seems to be for polycarbonate…
Also, do I need extra bearings and etc?
You don’t need an extra bearing. The one with whatever “C” bracket is all you need. The reamer I used was purchased at a radio shack. Just enlarge the hole with the reamer, install the servo as usual, then install the bearing into the servo case bottom instead of the ASB-04 using the same 3mm screw that comes with the brackets. It’s pretty simple really.
Only, ream from the inside of the multipurpose bracket.
Jim did the reaming from the outside, which leaves only a tiny edge of metal on the bracket touching the plastic.
If you ream it from the inside, you should be able to get it ‘just right’ so that the reamed edge hugs the small corner radius on the plastic. Which, in theory should make the bond slightly stronger.
Thanks for the tip you two. Funny, I don’t remember asking if I needed an extra bearing, but there it is… 
What kind of reamer is this? Is it a step reamer used in electrical work? Why not use a 25/64 or 3/8 drill bit?
Thanks, Connor
I purchased one off of Amazon. My local Sears ticked me off by the fact that their sales person did not understand what a “tapered reamer” was. The sales person then proceeded to further cover up the lack of knowledge by trying to talk me out of using one, and questioning why would anyone need it…
A reamer, when used in a controlled manner, is a very precise way to enlarge a hole while still keeping the original center… Since it should eat into hole evenly (because you’re turning it), it’s a great way to keep it centered… I suppose a drill bit can do the same, but I don’t have a proper drill press to keep it nice and straight…
A reamer is also good when you truly need a precision fit… Not all parts mate correctly due to tolerancing, so for precision hand fit, reamer tools are often used… Also, since it’s hand/wrist operated, it’s a great way to enlarge a hole in plastics, which usually are very sensitive to RPMs due to heat from friction… If you’ve ever drilled plastic, they are a pain in the butt once they “gum” up on your bits…
This is the exact one I used and own:
amazon.com/Grizzly-H5890-Rep … 620&sr=8-7
You can use any other brand, I just happened to buy the Grizzly one.
I use the reamer for all kinds of things. I reamed out the hole for the hinge on the ASB brackets for the HSR5990 servos. I also use it to ream out body mount holes on my RC car bodies. I’ve also used it to ream out SPUR gears for my RC, where keeping the true center in the mounting hole is VERY critical…
