josecarlo1129

iTrader: (1)

Same here. It took me almost 2 days trying to set the FFG system up. Sanding is indeed a must but only minimal. It should sway smoothly, freeing up the front gear-box as it should be.

FreddySudhoff

Hi guys,

can you please let me know on what position the FFG is not moveing freely? I have built several prototypes and production kits for testing and never had any issues to get it move free.

I will try to help as best as possible.

Freddy

Quantra

I'm curious to know if anyone has been unfortunate enough to crash hard with an alloy chassis fitted? Did it tweak or is this not something to worry about?

John Doucakis

iTrader: (1)

I think it depends on what people define as smooth movement.
Freddy, in my videos shown would you label it as smooth movement?
In the video I accelerate and break, is the movement sufficient or is it too little?

http://www.youtube.com/watch?v=qGthUZePBUg

http://www.youtube.com/watch?v=iJXy6DZWUTk

A friend who saw your car notified me that yours was moving a bit more but you were also applying steering input as well.(I made sure it does not bind anywhere, but I had the two central rings secured tightly on the middle tower. I understand you are running with these two rings free of the middle tower?)

What are your thoughts on this?

Regards,
John

Jerry P

iTrader: (44)

I've seen Hanulec crash hard with the metal chassis. No tweaking issues there.

FreddySudhoff

The alloy chassis is at least with AM30 or AM33 quite crash resistent. I still use in my car the first alloy prototype and crashed twice pretty hard. Still nothing bend.

In the video it's hard to see if this movement is enough.
The feeling of the FFG depends on two things:
1: FFG with Topdeck
2: FFG without Topdeck

To1: The car should be pressed on a flat surface. Then mount the topdeck and tighten all screws. After that, the FFG should move free to left and right and slightly up and down.

To2: Please pay attention. We have two situations here! First, the car stands on his 4 wheels. Due to no Topdeck, the chassis is a liiiiitle bit bend (depends on the setting of P31). Front and rear end is "higher" then the middle.
Second. The car stands on the carstand. In this case, the chassis is flat or at least a liiiiiitle bit bend, BUT front and rear and are lower then the middle. This means the FFG will be not that free anymore.

Also the settings of AM50 and AM48 (around the middle post) will have a big influence. To tight will prevent the FFG from free movement. On some high traction tracks we run them with a gap from some millimeter so they have no influence anymore. But on low traction we recommend a setting from 0.2mm gap.

Freddy

gocoogs

iTrader: (24)

I will do my best to explain literally without the use of video or pictures as my car is at home and I am at work...

As I see it, the FFG moves 2 ways... laterally and rotationally. The way my FFG is now, If I were to take a 1.5mm wrench, stick it in the small hole near the front mount (as in JDs video) and move it manually laterally from center to left for from center to right, it stays on the left side of the gearbox casing if I move it left and it stays on the right side of the gearbox casing if i move it right. I would describe the feeling as "free and easy" to move it laterally, but it stays in the position I put it in ... it does not return to 'nuetral' or 'center' un-aided.

The second sort of movement the gearbox is capable of is rotational movement. as it stand now, my FFG moves with very light pressure down to the right or the left, but again, a manual movement on my part results in the FFG not returning to nuetral or center. If I manually push my FFG down to the right or to the left, its stays there. So if I press the right side of the FFG down, it stays down to the right... and the same is true if I press it down to the left. I can manually center it, and its easy to do, but in no way right now does it return to its original position without me manually putting it there.

Now... as I build the FFG, I observed 5 points where it rotates/moves and could have friction.

1) where the bottom of the FFG contacts the curved part of the gearbox casing... in the instructions it notes to use the '3m low friction Magic tape' to aid in reducing that possible binding area...I have done that.

2) where the bottom of the FFG contacts the top part of the gearbox casing and is exposed to friction in lateral movement. In my instructions there are no notes for remedies in that section, but based on my observations, that doesn't seem to be an area of concern or bind.

3, 4 & 5) where the carbon tube connects to the back of the FFG, the middle post and the rear mount. the front and rear points have small hex set screws that aid in securing the tube. According to what I remember reading in the instructions, they said to lightly score the tube to aid in the insertion of it into the mounts. I did that 'lightly' and i didn't feel it was free enough. (For reference, my definition of 'free movement' would be feeling the movement of the carbon tube inserted in the mount rolling it back and forth like you would an allen wrench starting a screw in a machined threaded hole). As a result of the lack of 'free movement' based on my definition above, i sanded the end of the carbon tubes more until i got the free movement I was looking for before tightening the set screws. I achieved that feeling after a little more sanding, and thought it would solve my issue.

As I have addressed all the points above as I observed to be 'friction points', I assumed the FFG would be free... but its not. Even when my set screws are completely removed, my FFG still remains 'static' once I move it into a position either laterally or rotationally. It is not 'elastic' in any way by returning to neutral unaided.

Now keep in mind, I haven't put force on it with a motor and maybe that changes things... but I wanted to get it right before I put it on the track. I hope my explanation is clear ?

Thanks,
Justin

John Doucakis

iTrader: (1)

Same thing with mine. It does not center itself, although it does tend to move back towards the center line when pushed to the end of one side. It just does not center itself completely.
To me it is clear that the friction points that prohibit it from centering itself completely are the two rings which I have tightened against the middle tower and the gearbox cover which is in contact with the surface of the chassis.
I assume that if I loosen the two center rings against the middle tower as per Freddy's instructions the system should center itself a bit more.

John

Quantra

Thanks for the info on alloy chassis durability. All sounds good =]

Oleg Babich

I know five possible reasons of the excessive friction at FFG gearbox movement:

1. Wrong orientation of AM41 (step #14 of FFG/Evo Instruction Manual).
I know already several drivers that have tryed to install AM41 in the position that was opposite.

2. Bad fitting of P10 diff covers. Lower P10 presses on on the chassis to much at this. You have to to remove all burrs and excessive material on both P10 and to check the full good connection of one P10 to other P10.

3. Wrong orientation of AM56 (step #18 of FFG/Evo Instruction Manual).
At this mistake AM56 presses on P10 too much and deflects them downwards. Lower P10 presses on on the chassis to much at this.

4. Excessive friction between DT04 collars and AM49. Please adjust the gaps.
( step #40 finished ).

5. Excessive friction between P31 collars and AM54. Please adjust the gap.
( step "#40 finished").

Please pay your attention on step #39 of instruction and align FFG rod axis to chassis axis by means of proper tightening of rear AT21/screws over AM40.

Please remember also that the top surfaces of AM40 and AM46 plates should be parallel ( step 38 finished).

kgombe

iTrader: (13)

so should the FFG return centre on its own if pushed to one side manually?

gocoogs

iTrader: (24)

thanks so much oleg, I will go thru those steps again when I get home!

Oleg Babich

As 100% zero friction is the fiction so FFG should return by himself only "almost to the center". Some minor friction is useful as it dampens the oscillations of FFG.

John Doucakis

iTrader: (1)

Oleg or Freddy,

Since you propose to have the middle two collars with some space from central tower, does this mean that you always allow some transverse flex of the chassis during racing, i.e. front moves up & down.
In order to have zero (0) flex up & down of front or rear end then we need to install the top deck, correct?
John

JayBee

iTrader: (31)

Kody's moves as described above by Korgae. I can confirm this. I've played with it several times....when he first put it together (it was pretty free). But after awhile of moving it by hand from a few folks, it started to bind. Kody's a perfectionist and whatever he did, I don't know...but when I had a chance to see it again, it was nice & smooth. And returned to center. I didn't sit there and measure the movement though. I'll try and get him to chime in.
BTW...Kody has recommended to several of us to indeed use the top deck.