Muggy to 5BE Build

[JERRY2KONE]

Yea this looks like a fun build project. It is fun to come up with new ideas and try things that others may have failed at, but in the end you learn more about R/C design and construction. It kind of lets you see exactly what some of the manufacturers have to go through in order to come up with a half descent vehicle. Trial & error is the best way to learn. I do like that piece of channel you came up with, and for free. Can't beat that with a stick.

Considering the sheer size of your build, the size of the 1717 motor and the added stress you are giong to put through this thing you really do have to elliminate your drive line weak points. Using plastic in any of your drive line IMO is just asking for trouble. If you want this thing to last for any length of time get your diffs all setup in alloy to avoid inevitable failures. If there is any way to use hardened steel gears I would do it. Alloy diff cups and cases will give you ultimate strength, reduce flexing, and help avoid disaster and more delays. Just my 2 cents. Nice project, keep up the great work, and thanks for sharing your experience with us.

[zueslilbuddy]

Originally Posted by lincpimp

Some good lst info for your build, which is great!!!

If you want to move the cd forward to cut down on the ft shaft length you can use a lst1 wheel cvd shaft, it will fit the cv end that attaches to the rear diff.

I would suggest using the HD cups with al diff cases. Or try to scare up some nova rc al diff cups. The hd cups work very well. They will not explode like the center cup did!

Build looks great. I happen to have a section of al channel I purchased a few years ago to make a buggy out of lst/muggy parts. I planned to use a xlb body I have, so it would not be 1/5th scale, more like 7th scale.

Looking good, keep up the great work!

Thanks for the info, I think I know where I can get a lst1 wheel cvd

[Candyman2]

If your putting a centre prop shaft in make sure you use something like 8mm/10mm tube to extend it. Dont be tempted to use bar as it will bend, has to be tube.

[zueslilbuddy]

Originally Posted by Candyman2

If your putting a centre prop shaft in make sure you use something like 8mm/10mm tube to extend it. Dont be tempted to use bar as it will bend, has to be tube.

Thanks for the advice but I'll be using Hardened Steel rod.
Having it made up at the machine shop very soon.

It will not be welded, but will be like v8hatch's with the set screws to make it easier to change out the shaft ends if I happen to break a dogbone end or cdv end.

[Candyman2]

fair enough but at that length i'd still go with tube, time will tell. :)

[brian015]

Originally Posted by Candyman2

If your putting a centre prop shaft in make sure you use something like 8mm/10mm tube to extend it. Dont be tempted to use bar as it will bend, has to be tube.

This makes no sense - a solid rod is stronger than a hollow tube of the same OD.

Originally Posted by brian015

This makes no sense - a solid rod is stronger than a hollow tube of the same OD.

I'm pretty sure tube is stronger in a driveshaft application,never seen a solid shaft on anything full size either.

[brian015]

So you take a solid rod and drill a hole through the middle, making it hollow, and it's stronger?

Take note, that I say "of the same OD" - to make his driveshaft out of the cvd pieces fit into either a tube or solid shaft drilled out at the ends he must have a similar OD rod or tube.

A tube of the same weight as the rod (meaning it's made from the same amount of material as the rod) will undeniably be stronger. But that is not what is under discussion.

[Candyman2]

Originally Posted by brian015

This makes no sense - a solid rod is stronger than a hollow tube of the same OD.

lol: do some research bud.

years ago they made propshafts on cars out of bar, they would twist unless they were REALLY thick and very heavy, a tube of the same diameter with a very thin wall (1mm) is just as strong and will resist and bending.

Originally Posted by brian015

So you take a solid rod and drill a hole through the middle, making it hollow, and it's stronger?

Yes, fact im afraid, it will resist the torque and not bend, strange but true, thats why all car props are made that way, makes them much much lighter than solid aswell.

[brian015]

Originally Posted by Candyman2

lol: do some research bud.

OK: http://wiki.answers.com/Q/Which_is_s...low_steel_pipe

http://answers.yahoo.com/question/in...7125516AAcFkuI

http://www.off-roadweb.com/tech/1101...ube/index.html

Bottom line: what I stated in my previous posts is exactly right. Again I say that a tube made out of the same amount of material can be stronger, but it will have a larger OD - that is not what is under discussion here.

[Candyman2]

never mind,

sorry to clutter up your thread.

Good build, keep it up :)

[brian015]

Originally Posted by Candyman2

THAT is right yes, its stronger as in , if you try to bend it, but NOT for torsional rigidity, i.e if you twist it as in a propshaft. A tube wont twist under a load where as a rod of the same diameter, like in this particular application, will. Im not a mechanical engineer, but it has to do with it having twice the surface area, inside and outside rather than a bar only having 1.

So please back that claim up with some evidence.

[zueslilbuddy]

Originally Posted by Candyman2

never mind,

sorry to clutter up your thread.

Good build, keep it up :)

Don't be sorry, disscussion is a good thing, its how we learn.

I have been using brian's and v8hatche's builds as guides and when I asked v8hatch what he used for his front shaft he said this.

Originally Posted by v8hatch

It's solid 12mm rod, it's all i had. I took it to a guy i know that has a lathe and drilled into each end then drilled and tapped the side for the grub srcews.

So since this has been working for him I figured it would be a good way to go since like I said before.
It would be cheaper and easier in the long run to make the shaft like his.
I'f say the dog bone end happened to twist off the shaft, I could just loosen the set screws and change it.

Funny thing tho, show me a monster truck (rc) that runs dog bones, that has hollow dog bones?
The only hollow ones I've ever seen were slider shafts, and we all know how easy those twist (usually plastic).

I don't know, I'll go with what I've planed out and if by chance a solid hardened steel shaft breaks I'll try tubing

[Candyman2]

You'll be ok, that hardened shaft should resist a small bomb going off!

Since yourgoing so over kill on the shaft anyways forget my post,you won't have enough power to twist that huge shaft,your weak point will be the smaller components anyway