Too much slip
 

my setup is a 40 x 82 mm 2000kv motor, 4 cell A123 batteries and 14T pinion in a Muggy. I lightly scuffed the slipper pads. I made sure none of it got anywhere on the slipper when I lightly greased the threads on the adjustment ring. I have it tightened all the way down and it still slips so much the truck will not barely move. Is something wrong ? or do I just need another spring maybe in this heavy truck with a 2000kv motor?

http://www.youtube.com/watch?v=VnQ06skycxU

It shouldn't be slipping much at all when it's tightened down.

I'll ask a silly, but relevant, question: Were there any parts left when you finished assembling the unit? :lol:

Can you take a side-on picture showing how the parts are arranged, just to confirm the unit is assembled correctly?

I believe the axial relationship of the springs can affect how much pressure they apply. They have to be lined up with each other a certain way.

I will take it out next week and post some pics. I did not have any extra parts.

Tried two different camera and every picture is blurry. I will take it apart tomorrow and post pics of the components laid out in order they are installed. Im pretty sure I have it right per the instructions. Im hoping something is wrong though so i can get it working.
http://s9.photobucket.com/albums/a10...slipperential/

Try a different photographer :lol::lol:

Yeah I can't tell anything from those pictures...

I thought of something you can check- Make sure the side of the spur gear with the fiberglass friction pad inserts is facing the large end-cap of the diff. The flat side of the spur gear should face the large thrust bearing toward the small end-cap of the diff. If the friction pads are facing the wrong way it will cause the behavior you are seeing. Other than that I don't know...

Did you scuff the pressure plates with sand paper?

Yep. I scuffed em. I followed the directions carefully. I will take it apart tonight. One of the pads was slightly deformed and I sanded it a little to get it to pop in place. Maybe its causing an issue?

I wouldn't have thought that would be the issue. If one of the pads is thicker or not seated properly and taking all the pressure that might make a difference. The slippers I have I gave a reasonably good rub with sandpaper so none of the original surface was visible. I did that cause I heard of others saying they couldn't tighten it to the point they were comfortable with (nothing like your scenario though).

slippery slipper
 

It is quite hard to see in the video, but it is easy to hear the slippage. Something is very wrong to have this much slip. Scuffing the slipper rings(particularly the one engaging the slipper pads) is important not only for traction, but also because there is a greasy residue on the rings from the manufacturing process.
Also, what grease did you use to grease the adjustment ring threads? I have found that AE black grease works the best - this is also a very important step, as dry or improperly greased threads will not allow you to fully compress the springs (they don't need to be fully compressed usually to work, but they must be compressed a bit to apply enough pressure on the slipper assembly). With the appropriate grease, you should be able to flatten the springs with fairly light pressure.
Aside from that, the only other cause of excess slip(assuming proper assembly) would be oil or grease somewhere on the slip surface(pads or ring). Can you post a couple still pictures of the assembled diff?

I took it apart last night and it was assembled correctly, there is no grease on the pads or slipper. It was tightened all the way down. Tonight i will use my video camera to make a video fo me re-assembling it that way if you guys notice anything you can let me know. THen Wed night I can put it back in the Muggy and see how it goes. It looks as if it was assembled correctly per the directions though.

Here it is:

http://youtu.be/nM8FOb2bbbs

What weight diff oil are you using? From what I can tell that's how I put mine together. I have not had a chance to run my truck because I'm still waiting on parts.

In the video you mentioned that you tightened it as much as possible, but the springs were not completely compressed, indicating that the perhaps the threads were not greased adequately. You should be able to completely flatten the springs without excessive effort – especially when out of the truck.

Also, you did mention the grease in the video - you are using the AE grease to grease the threads on the diff cup/adjustment ring, correct? You do have a large, heavy truck, so I expect the need for a tight setting, but you should be able to make full adjustment if the threads are greased well(meaning you should be able to completely flatten the springs against the slipper assembly).

Is it possible the diff body isn't threaded far enough to allow full travel of the tightening ring?

It was greased well and tightened easily, it is tightened so that the springs are almost perfectly flat. The ring is so tight there are only threads on the bottom half of the ring. There is absolutely no way to tighten it any mroe than it is now so if thats the only solution this will not work for me at all.

It could be a possibility.

only possible if the slipper side(large) endcap isn't completely tightened flat to the diff cup(this would also result in a leaky diff of course). Everything is sized to allow assembly with minimal spring tension and also allow full tension when tightened - the nut will partially disengage the threads when fully tightened, but will not thread itself completely off the threaded portion of the cup.

Given it was designed for racers with lighter vehicles, your setup may just be a bit too much for the slipper, in which case add an extra wave spring. You shouldn't run out of thread then.

I just tried to tighten my wave springs down some more and I just broke them. My truck will most likely be even heavier than your truck so I might be in the same boat. I am interested to see if you will need extra wave springs. What holds the wave springs together? Are they glued, soldered, or welded? Both spring came apart at the overlap sections. everything else seems to be OK. I have more springs on the way, but if I can fix the ones I have I would like to.

The springs are simply overlapped - not welded, glued or otherwise at the overlap section. You didn't break them at all - they came that way. :)

Thanks, Mike. I just got home and took it apart. All is well.

So I would like to know if you tried the third wave spring and if so did it work?,or did you get it worked out some other way?

To be honest I haven't tried it myself, haven't felt I need to. Though I do have a spare set of springs so I can try it, just won't be able to drive it until parts get delivered :cry:

I got the third spring on last night and with the third spring and it tightened all the way down it works! The front end comes off the ground a little tiny bit on launch but no more flips or wheelies and my drive train should be safe now. So I guess with 3 springs it will work good on a huge truck like the muggy. Im happy with it now. Im running a 15t pinion, 4 cell A123 batteries and a 40 x 82 mm 2000kv 4 pole leopard motor. It moves pretty good! I will try to get some video posted when it stops raining.:party:

What diff fluid are you using in the slipper?, and do you know how much you truck weigh's?

I was using 50k but last time I rebuilt it I had no fluid left so i just used diff grease. I have no idea how much my muggy weighs. Im guessing around 13lbs.

Pity I didn't spot this thread sooner as I had the same issue with the slipperential in a Savage and solved it the same way
http://www.rc-monster.com/forum/showthread.php?t=27208

One thing note is to make sure the overlap points in the 3 wave springs are evenly spaced out when you put them on. This seemed to be part of the issue with just two as when they were really tightened down it seemed to create uneven pressure on the slipper.

I could actually use 4 springs on mine if i wanted more adjustment area cause I got the springs flattened now. But im good with it where it is :intello: