Why are buggies built this way?
11-06-2007, 02:21 PM
#16
Tech Fanatic
Sportwerks' Mayhem & Turmoils have split center diff holders. I'm surprised Losi didn't copy that.
11-06-2007, 02:24 PM
#17
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#1 I don't see how keeping the steering components the same but lowering the plate (i.e. makign the arm on the bellcranks at the bottom/flippign the bellcranks upside down) will reduce the steering slop any. If the plate was super low/on top of the chassis, then the plate/steering links would hit the track when the car is bottomed out and landing at an angle.
#3 Not a bad idea to make the bulkhead open from the top like the 4wd electric BJ4/B44, NTC3 cars do but it would be as much ro more work possibly as you would now have to deal with the shock tower/camber links, and shocks as being the things in the way when removing the top of the bulkhead.
#5 To off-set the driveshafts isn't that easy. They need to be on one side of the front diff and the opposiet side of the rear diff to make the f/r wheels spin in the same direction...otherwise you'll have the tires fighting one another spinning against themselves. Then to off-set the driveshafts you are limited by the steering parts or other parts within the chassis that pretty much have a standard size (Rx batteries) which limit the room you have to play with.
#3 Not a bad idea to make the bulkhead open from the top like the 4wd electric BJ4/B44, NTC3 cars do but it would be as much ro more work possibly as you would now have to deal with the shock tower/camber links, and shocks as being the things in the way when removing the top of the bulkhead.
#5 To off-set the driveshafts isn't that easy. They need to be on one side of the front diff and the opposiet side of the rear diff to make the f/r wheels spin in the same direction...otherwise you'll have the tires fighting one another spinning against themselves. Then to off-set the driveshafts you are limited by the steering parts or other parts within the chassis that pretty much have a standard size (Rx batteries) which limit the room you have to play with.
2) I looked at and discarded a top-loading diff. Too complex without completely redesigning a buggy from scratch. Not something I want to do.
Instead, what I had in mind was a 3-piece bulkhead instead of 2. Split the front above the hinge pins, make that part removeable independent of the lower portion. Suspension stays attached, diff comes out. Less headaches changing setup or simply maintaining the car.
3) Not exactly. The diff doesn't care where the ring gear attaches. It could be dead center on the diff, or on either end, or anything in between. What matters is the direction that the gear faces. Assuming we are dealing with the same direction of rotation as every other car uses, the teeth of the ring gear have to face to the right on the rear, and to the left on the front. That is the only limitation in concept. However, you also have to package everything else around it, so making it all fit together is not that simple.
Good discussion folks!
11-06-2007, 02:34 PM
#18
I guess the main reason buggies are made like this is that (until some amazing break-through is made) this design is the one that works the best (with small variations), at the same time keeping it simple for us modelers to use.
Still, I'm sure the pro "think-tanks" are always avid of new and innovative ideas to work with. It might even be worth it to copyright any feasable ideas one might come up with, and then offer them to some RC company...or directly apply for a job!!!
11-06-2007, 02:38 PM
#19
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I guess the main reason buggies are made like this is that (until some amazing break-through is made) this design is the one that works the best (with small variations), at the same time keeping it simple for us modelers to use.Still, I'm sure the pro "think-tanks" are always avid of new and innovative ideas to work with. It might even be worth it to copyright any feasable ideas one might come up with, and then offer them to some RC company...or directly apply for a job!!!As for the second... I'm not looking for a job. I'm happy with the one I have, at least most of the time.
Nor am I looking for the next way to get rich... although I wouldn't turn it down in concept. 
I'm just looking to make our life a little simpler in what can be a sometimes frustrating hobby.
11-06-2007, 03:24 PM
#20
For number 3 look at what the savage x has. You can remove front and rear diffs with 6 bolts. Some people say it isnt quite as rigid as a 2 piece design, but i havent had any problems with flex from the case. I can see a buggy design only needing 4 bolts to release the diff.
11-06-2007, 03:34 PM
#21
#2- Center diff mounts: While some manufacturers produce split diff mounts, only Fioroni produces aftermarket split diff mounts that keep the upper plate attached to the upper half of the mounts, hence keeping the brake assembly intact and making disassembly and subsequent assembly easier and faster.
11-06-2007, 06:04 PM
#22
why would I need to use spell check on rctech? many more inpoortent tings too du!
11-06-2007, 06:36 PM
#23
Team Magic M1 is for you!
A lot of the ideas you have are on the M1
A lot of the ideas you have are on the M1
11-06-2007, 07:22 PM
#25
#2- Center diff mounts: While some manufacturers produce split diff mounts, only Fioroni produces aftermarket split diff mounts that keep the upper plate attached to the upper half of the mounts, hence keeping the brake assembly intact and making disassembly and subsequent assembly easier and faster.
What I would like to see in a buggy design would be a chassis that has a Ti or steel plate on the bottom, 0.75mm thick, then a carbon plate, 2.5mm thick, on top of that to make it rigid, but keep it light. And instead of having the front rear, and rear front arm mounts bolt onto the gear boxes, have them machined right into the chassis as just little nubs that stick up and accept a eccentric plastic bushing. Sure it would cost $200, but it would last forever since the Ti or steel wouldn't wear through like aluminum, and it would be lighter too with Ti.
11-06-2007, 07:47 PM
#26
Tech Master
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I guess I tend to over-analyze things... but maybe one of the manufacturers will see some of this and put it to use...
1) Why is the ackerman plate and related steering linkage stuff on top? Why not put them down in the chassis, UNDER the front driveshaft? It would help lower the CG AND help prevent some of the slop in the steering.
2) Why doesn't everyone make the center diff mount in such a manner that you can remove the top portion with the brakes still assembled, leaving your setup intact? Mugen does this, but some of the others don't. I even thought putting the brakes UNDER the diff would be a good idea, until I looked at how complex the linkage would get... lol
3) Why don't they make a "quick change" gearbox case/bulkhead/whatever you want to call it? Make it so the hing pins remain in place and you simply remove the top of the section at the front or rear of the car. MUCH easier to change diff fluid for different track conditions! Put the swaybar to the inside, not hanging out front or in the back to further simplify matters. It would be nice if changing a front or rear diff was as simple as changing the center diff.
4) What's the deal with hump packs? The stick pack batteries, especially if you lay them down, would lower the CG of the car. For that matter, make it so the mount is somewhat adjustable to allow weight bias to be adjusted front to rear.
5) While Losi had a good idea in reversing the way the teeth face and keeping the pinion on the same side for the front and rear diffs, I don't personally think they took it far enough. Offset those gears further to keep the driveline STRAIGHT. Put the pinion in the same spot on both ends, and build the ring gear so it is offset enough to clear the difference- offset to the inside on the rear and to the outside on the front. Less wear on the CVA's.
6) This is specific to pivot-ball cars: Why not use spherical rod ends with bolts to retain them instead? Make an "E-hub" so the rod are sandwiched between portions of the hub, so the retaining bolt is ONLY loaded in shear.
Spherical rod ends will take huge loads, and virtually no wear, so no slop and inconsistancy.
Ok, enough of my rambling for now. Anyone else have any ideas to improve buggy technology? This stuff almost makes me want to design one myself, and find some third-world country to set up manufacturing in.
1) Why is the ackerman plate and related steering linkage stuff on top? Why not put them down in the chassis, UNDER the front driveshaft? It would help lower the CG AND help prevent some of the slop in the steering.
2) Why doesn't everyone make the center diff mount in such a manner that you can remove the top portion with the brakes still assembled, leaving your setup intact? Mugen does this, but some of the others don't. I even thought putting the brakes UNDER the diff would be a good idea, until I looked at how complex the linkage would get... lol
3) Why don't they make a "quick change" gearbox case/bulkhead/whatever you want to call it? Make it so the hing pins remain in place and you simply remove the top of the section at the front or rear of the car. MUCH easier to change diff fluid for different track conditions! Put the swaybar to the inside, not hanging out front or in the back to further simplify matters. It would be nice if changing a front or rear diff was as simple as changing the center diff.
4) What's the deal with hump packs? The stick pack batteries, especially if you lay them down, would lower the CG of the car. For that matter, make it so the mount is somewhat adjustable to allow weight bias to be adjusted front to rear.
5) While Losi had a good idea in reversing the way the teeth face and keeping the pinion on the same side for the front and rear diffs, I don't personally think they took it far enough. Offset those gears further to keep the driveline STRAIGHT. Put the pinion in the same spot on both ends, and build the ring gear so it is offset enough to clear the difference- offset to the inside on the rear and to the outside on the front. Less wear on the CVA's.
6) This is specific to pivot-ball cars: Why not use spherical rod ends with bolts to retain them instead? Make an "E-hub" so the rod are sandwiched between portions of the hub, so the retaining bolt is ONLY loaded in shear.
Spherical rod ends will take huge loads, and virtually no wear, so no slop and inconsistancy.
Ok, enough of my rambling for now. Anyone else have any ideas to improve buggy technology? This stuff almost makes me want to design one myself, and find some third-world country to set up manufacturing in.
11-06-2007, 09:24 PM
#28
Hey Domit
2- Qconcepts makes a 2 piece centre diff mount for the losi that does exactly what your after
by the way I like your way of thinkin why be happy with what youv'e got if it could be better
2- Qconcepts makes a 2 piece centre diff mount for the losi that does exactly what your after
by the way I like your way of thinkin why be happy with what youv'e got if it could be better
