Brushless Truggy Part 2 - RC-Monster Forums

suicideneil · 03.25.2008, 06:36 PM

It must be nice having a vertical mill, I really need to get a cheap one sometime- so many ideas, so few resources.

Looks good so far, the seperate motor mount does make using mech brakes front & rear alot easier = options.

Shark413 · 02:30 AM

It's a real cheap mini-mill, I got tired of drilling and hand filing. I spent more time working on the mill (getting it true) than on making parts. I have an RC-Monster motor mount that I could have used with a spacer to set the motor back, but it was an older model and wasn't machined for the brake parts. So I decided to make a simple mount from scratch. Eventually my setup will include a rear support for the motor so all the stress doesn't fall on just two endbell screws.

My Neu motor cost more than this mill.

Shark413 · 03.26.2008, 02:38 AM

Update:

Here is a test fitting of the carbon fiber battery tray. Eventually the tray will have two sets of straps and a small aluminum brace to keep the battery from hitting the center diff/spur. When it is all done it should weight about 3.5 ounces.

Here is a similar tray in my buggy. This is what the finished version should look like.

Shark413 · 03.28.2008, 05:07 PM

Ran, into my first major issue. The CEN TR uses 26T/9T front/rear diff gearing (2.888888) which is pretty high. The nitro CEN uses a 52T spur to make up for the high diff gearing but I am using a 46T plastic spur. Even with an 11T pinion I get a top speed of around 50mph, too high for what I need (track). I was going to pop in some spare Kyosho diffs I have, but I remembered that the CEN TR has really long outdrives and the Kyosho has shorter ones, using the Kyosho outdrives will cause the dogbones to pop out. So I guess I will try and mate the Kyosho ring gear and pinion to the CEN diff.

jhautz · 06:06 PM

Actually the CEN Matrix BUGGY uses 26/9 gears in the diffs. The truggy uses 38/11. Its still rather high for a truggy (actually very close to what most buggies use, 43/13) but not as bad as what you originally thought.

When I converted my CEN truggy I found the same thing. I started off with a very low KV motor to compensate for the tall gearing and 46T center gear. Eventually, I actually switched to the Hot Bodies 43/10 truggy dif ring and pinion to lower the ratio and allow the use of a 46T spur gear without a super small motor pinion. The HB ring gear and pinion fit the CEN difs with a little careful shimming to get the mesh right.

EDIT: What are you planning to use for chassis braces? The stock over the top braces dont look like they will work with your center dif arangement.

Here is a link to my CEN Matrix TR thread in case you are interested.
http://www.rc-monster.com/forum/show...ight=matrix+tr

Shark413 · 09:43 PM

Hummm .. I have both (CEN buggy and truggy) and in my case the truggy has the 26/9T and the buggy has the 38/11T. Thats why the buggy uses a normal size spur and the truggy uses the ferriswheel spur. The teeth on the truggy ring gears are huge, probably why they could only fit 26 teeth on it. I have Kyosho ring/pinion gears and they fit on the CEN diff, so that may work (Kyosho ring/pinion with CEN diff). If that fails, I will stick the CEN buggy diffs in the truggy since the gearing is lower. And I am using a lower kv motor (Neu 1515 1Y). Regarding the brace, I saw someone else (may be you?) convert a CEN and they used spacers to match up the Kyosho diff mount to the CEN chassis brace. I have HB spiral pinions from another project, but the ring gears are gone (another project). Sounds like you have plenty of experience converting a CEN truggy, so keep the suggestions coming, while I am still in the planning/building stages.

jhautz · 10:19 PM

I'm not sure where you got your buggy and truggy from, but from the factory the Buggy comes with the 26/9 gears and the truggy comes with 38/11. Check your part numbers and manuals. The huge teeth you are talking about belong in the buggy and are mod1.5 pitch instead of the normal mod1 pitch gears.

Matrix Arena comes with MXS38 Steel Ring Bevel Gear-T38xM1
Matrix Buggy comes with MX040 Ring Bevel Gear d6(26T)

I have both as well and actually moved the CEN truggy difs (38/11) to the buggy and put the HB 43/10 gears in the truggy. That gives them both "normal" (or very close to it) gear ratios.