Brushless Buggy ?
 

I'm considering building a BL 1/8 buggy. I would like to know can i get good speed & runtime on only 7 cells, if so what motor & speedo would be recomended ?. Thank's

Leave the small cell counts for LiPo and 1/10's, this is a big car, it can do (and needs) more! I have a converted Ofna 9.5 with a Lehner 2800xl and Warrior 9918 controller that FLIES on only 12 cells geared 12/52.

Is the center gear metal or plastic ?. If plastic was the diff a direct replacement ?. I was looking at the ofna hyper 7 tq sport buggy. I was thinking i could always if i had too get a hardend pinion & use the metal gear center diff.

Yep, I would just get a hardened pinion and use it directly on the stock metal spur.
I hope I can get a nice roller for my winter-project. I'm looking for a Mugen MBX4 or 5, or an Ofna 9.5 Violator.

I would also suggest 12 or more cells, or LiPo.

Hi dafni !!!

I came to the conclusion that getting a hardened pinion is the easyest way to do it. Also buy doing that i can get a better buggy. Lipo's are'nt really a option to pricey. I was thinking about the ofna hyper 7 pro kit, or the xray xb8r kit, or thr sportworks arr mayhem. All those buggys are right around $400.00 new.

Hi Hippie! Similar project again, eh?

As stated elsewhere, I could harden some pinions myself, but I think RC-Monster Mike will come up with a batch too.

I hope I can get a good quality buggy to convert. Those Mugens are awesome!!
The Ofna Violator has a nice wide stance.
I got an offer from a friend of a friend for a Kanai2 roller for 100bucks. Let's see. I plan to do this project in the winter days.

Yes, I am also putting Lipo on the backseat. But one day, I'll have to try them. But before that I HAVE to get a real radio :o

DAF

I'm shying away from buying a used buggy if i do this . I've bought used vechiles before and i've been burned. If i bought used i would have to know the guy & then the deal would have to be so good i could'nt pass it up:L: . I've found 3 or 4 buggys around $400.00 to choose from so who knows. I've thought about the mbx5 but its over $ 500.00 for the basic kit. The basic xray kit is $425.00 & the hyper 7 pro kit is $450.00 ouch.

You're right about used VS new cars. But for this project I think I'll go for a used top-of-the-line buggy. You can guess who's my oversea friend, right? And if He says it's in good condition, I trust him.
But so far nothing's signed and sealed. Let's see. No rush on this project, I have another one occupying the workbench at the moment. ;)

I would choose a buggy with a centered driveline, a little harder to find because manufacturers try to put the engive as close to the centerline as possible, but makes it a lot easier for battery mounting because you have more room. My 9.5 has a fairly centered diff (on the chassis), as do others.

I'm looking for a buggy with off-set center diff! Fits my idea better.

But basically you're right Dabid.

I'll chime in here too.
Elsewhere the use of a hardened steel pinion being used with a steel spur gear has been determined to not be a good thing. There is nothing better than to use a plastic spur gear. You get lower weight, less rotating mass, and something that wouldn't lead to a problem for both the pinion and spur (if the spur gear got stripped).

You're right, Metalman. The advantages are obvious. But a hardened pinion would be the easiest way out, in some cases.

Where are these "hardened pinions" everyone keeps talking about? I've thought of going to an all metal geared driveline after killing spurs in my Ofna 9.5, but know that the stainless ones Mike sells would die if they were used with the hardened steel spurs Ofna makes.

Oh, and Daf, I know there's different options for different people......an offset diff would actually work a bit better in some cases I bet.

Indeed, Dabid.

I talked to Mike about hardening pinions, and he said he might come up with a batch. But I could also do it myself, if it comes to it.

Whoa David, you are awake earlier than usual :). Hardened pinions are an option (no doubt), but the cost of them is pretty high. I would hate to hear of a pinion and spur stripping after a long period of use, since together the cost for replacement would be about $35.

There is always the way that I chose, and that is no center diff, but a center slipper clutch (using Revo parts) with MGT mod1 spurs (very strong). I have yet to strip a plastic spur gear! But that is also somewhat caused by the slipper clutch absorbing the things it should.

True. If I ever run a hardened pinion on a steel spur, I will get spares.

I had to drop my brother and sister off at school, that made me get up at 7:30......about 3 hours earlier than it was a couple weeks ago. :D

My major problem is that there are only two choices: diff or slipper. If you run a slipper, then you could just run it a bit loose and have metal gears that send any shock to the slipper.......but your handling and turn in suffers. Option #2 is to run a diff and get better traction, but blow out a spur on hard hits (remember Sheep Hills, Travis?). You can really only do one or the other, I would LOVE to make a system that: a) fits in the same space, and b) utilizes BOTH a slipper and a diff, for the best of both worlds. This way, you could still have the quiet-ness of a plastic spur, but the give of the slipper to take the shock out of hard landings as well as a diff to keep the handling up to par. Problem is, you're probably not going to be able to fit both of those onto a piece that can just drop into the vehicle......it'd have to be a least a little longer. Still, that would be mega cool........:Love:

Dabid, I'm sure Serum will respond to this ;)

Any help with that would be cool, I don't really know where I'd start though. :L:

Dabid,i've been thinking about this aswell.I'd like to use an e-maxx top shaft to drive a centre diff.

It may be possible to make a combined unit the same length if it was a ball diff because can't a ball diff be thinner?(pie in the sky,i know).

If you wanted to go with just the slipper the ofna dominator has a centre spool with a slipper.
i have one i may use in place of a tranny to get the ratio up for a 2240/12 on 8s lithium.(stand back to a safe distance:eek: )

Gustav - There are other options besides the top shaft for the Maxx. There is this HPI shaft which is what I use for my buggy's slipper clutch:
http://www2.towerhobbies.com/cgi-bin...4&I=LXFKF8&P=K
It is 6mm, so it is stronger than 5mm (Maxx top shaft). Also, most outdrives fit on a 6mm shaft, so this would fit without extra parts. The shaft would need to be cut down to fit though, and the sides would need a flat spot put on.
David used to use the Dominator slipper clutch. He said it didn't really slip at all. My reason for making one was that it is cheaper to buy the parts and put them together myself. Also, the spur gear is an inexpensive MGT gear, and there are a number of sizes to choose from (46t, 49t, 52t). It is a direct fit.

The idea of a slipper-diff has me thinking. I might be able to figure something out, but only time will tell.

EDIT:
Just thought of an idea to get a slipper on, but it will need the details worked in. Basically, the slipper plat/pad(s) mount onto the diff cup. Then the gear part would be tightened onto this "unit" (somehow, that's one of the details). The whole slipper-diff would require a larger space than a normal diff, but that can be figured out later.

Thanks MetalMan,so are you using that shaft as the output shaft with the diff driving it?(ignore this i've just noticed how stupid i am)
I was thinking the other way round,using the e-maxx shaft with the strobe and spur with an e-maxx input gear driving the diff gear.

Do you have pics of your set up somewhere on line i could check out because i think i've got the wrong end of the stick so to speak.(another edit, i've just realised you must just be using it as a centre spool,no diff at all,silly me.No need for pics sorry.)

I just saw your edit,now your talkin',I don't see why that couldn't work.I'd be fairly long though by the time you factor in the slipper spring.You could use a collar threaded on the shaft to tension the spring like on that ofna slipper.
Get that to work and we'll have to get your RC Monster status thingy upgraded to Genius.

Brain fade or what!:L: :L: :L:

It is late here though.

I do have pictures of my current slipper setup. It actually uses a collar to hold on the spring, like the Dominator's slipper. I tighten the slipper by sticking it in the vice and put pressure on it by using a hand clamp. Here is a picture:
http://img.photobucket.com/albums/v1...r/IMG_0749.jpg
Just in case you are wondering, this is a custom mount (by me) for this setup that has a built-in motor mount (you can see the purple Feigao motor).

In regards to your questions/ideas,
I don't think that you could get the Maxx idler gear shaft to work properly in a 1/8 buggy with a typical diff setup. Maybe if you were to make a picture in paint to show what you mean, I might understand better. But you have to remember that whatever you do, you need to be able to attach the outputs for the dogbones to go into.

Thanks,what i meant was building a tranny basically.
Using an input shaft (with slipper ) with an input gear driving the diff gear via an idler gear i suppose.The diff would be as is,complete with outdrives.(basically think of a single speed e-maxx tranny with a diff instead of the output gear).

It would't be ideal for me anyway because i don't want the gear reduction,extra weight/bulk.
That's why a combined slipper/diff would be ideal.

i'm going to ask my friend Billy who's been giving me lessons on his lathe if he can help with a combined slipper/diff using your idea with the diff case.

Any suggestions for slipper pad material?Do you think brake lining/pads could work?

I like your slipper.the dominator collar is threaded on though so you can adjust the slipper easily but that wouldn't be a problem with a lathe.

It could work something like this:
Centre diff with long output shaft out of one side/slipper plate screwed to diff where spur usually mounts(or just face of diff case)/pad/spur gear mount/pad/plate/spring/collar/bearing/outdrive.

Hard to describe but i'm sure this could work.Either that or i'm insane which isn't out of the question:C:

I'm not so sure thats correct. I havent seen to many spurs strip on the 1/8 buggy's but ocasonaly it happens. As for the extra rotating weight it is heavyier but the oiverall weight of the veichle is lighter. Plus the hardend pinion should last a while against the steel spur.

Problem with the slipper/diff I see is this: you gotta do it right, so it doesn't just unload to the front or rear. I could see this working it a larger two shaft design (like a tranny, just simple), which would either have to spread to the side, or go vertical.....either way, it's bigger than a diff or a slipper......and I can't think correctly right now for some reason. :D

This top shaft idea (slipper/spur on shaft, diff underneath) is not new! Altough it's more of a Maxx thing than Buggy. (needs more reduction)

The buggy oriented diff, with an incorporated slipper has also been discussed among some people.

Bring it on, tinkerers, Serum and me would like to see some creations!

Hi Dafni,I know i heard the top shaft idea on this forum somewhere before but i can't find it.

The reason the combined slipper/diff on the same shaft would be ideal for me is that i don't want the reduction because i'd like to run a Lehner 2240/12 on 8s (34500 rpm) to hit 60mph.(i'd need at least 22/51 with e-maxx 2nd gear). Plus i want the lower c of g it would give from lowering the heavy lehner.

Dabid, i know what your getting at but i think it could work if the slipper/spur was only on the input i.e with the slipper was on the diff case and neither of output shafts.

So imagine a diff cup with a very long part that the bearing usually sits on with the whole slipper arrangement on it.ie plate/pad/strobe type spur adapter/pad/plate/spring/threaded collar/bearing.

Like I said, Serum will reply to this, I'm sure. ;)

Gustav, you have a good idea with that. (an extended bearing thingy). To me, that seems like somethat that could only be made on a lathe. It would require a large nut too! (~3/8"). So basically, all that is needed is a back plate for a differential that would have an extended bearing mount, that would be cut on a lathe. I will try to design this piece on Solidworks.

Yes exactly right.The back plate with 'extended bearing thingy'.
Plus you need to make a long diff outdrive but thats no biggy.

I actually realised that sitting in front me is a vertigo diff locker which would look suspiciuosly like an 'extended bearing thingy' once it's been through the lathe to make the diameter 10mm all the way along the shaft and had threads put on after where the bearing sits.I'll probably make one from scratch but the locker could be used.I've figured out how to make strobe mount on a 10mm shaft(10x15mm bearing or bushing, strobe bored out to 15mm.And pads but they're already 14mm.)and fit in the length of the locker including plates, pads, strobe,narrowed sprong and big(but thin) nut.Whole assembly only c.1" longer than a stock diff.End of extended thingy sits on the usual 10x16mm bearing.

The flat back of the extended bearing thingy will be one plate,the other will be locked to it with a notch in it and short pin sitting in a groove running along the extenended thingy.obviously the pin can't go through the extended thingy because that would lock the shaft inside it.

Anyway hope that's clear as mud but as you say metalman it's actually rather simple:C: .

I was designing a back plate that would be compatible with a XTM diff. Ran into a problem. I don't know how an extened output gear could be gotten. If it were custom made, it would be expensive. But anyways, here is a picture of how far I got:
http://img.photobucket.com/albums/v1...ator/part1.jpg

On the diffs i've got(LST diffs) the diff out put shaft isn't permanently attatched to the out put bevel gear-just a shaft with a pin through driving the gear so all it would be is a long 6mm shaft with a hole through one end and an outdrive screwed to the other.

I wish i could post pics like that to demonstrate but i'm the world's worst with computers but you've got exactly the right idea.:)

I just looked at the LST's exploded view. I see what you mean with the diff! What diameter is the shaft on the outdrives?

6mm, so it would take a regular 1/8 scale outdrive cup.

My extended bearing mount/thingy has 6mm internal diameter(well slightly larger so the shaft spins freely and 10mm external diameter for plenty of beef.It'll spin on a 10x16mm bearing and sit in a regular buggy diff mount.

I guess I will be getting a LST diff! And I will have to find a place to get the back plate machined at.

Metalman how do i post a photo? I took them as e-mail sized files and saved them on my computer.Do i just copy and paste using the IMG thing in the reply page?

told you about me and computers:L: .

If you want an LST diff there's zillions on e-bay dead cheap.I've lunched a couple of bevel gear sets in them but i blame it all on hot racing diff cups.haven't had a problem with maximizer cups, in fact i'm getting another pair from Mike.Never had a problem when using the stock diff cups either though.Bevel gear sets are rediculously cheap any way and actually seem pretty tough,the outdrives are very tough too.