Re: 777 HAUL TRUCK (1/12 size)
 

Fuel tank pics...same type of "origami" ;)

The top and inside of the tanks will have cover plates to access and install switches etc ( may put a sound system in one tank later on)


[IMG]http://i1291.photobucket.com/albums/...ps9b87d4f0.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...psed024672.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...ps12f316e0.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...pscba1244c.jpg[/IMG]

Re: 777 HAUL TRUCK (1/12 size)
 

How well would your waterjet cut plastic styrene?

A 4x8 sheet of .100 might be cheaper than steel.

If this trk is 80-90lbs when finished, then add another 50-60lbs of dirt to haul... that lil banebot motor might just aint gonna do it?! :eek:

A tube axle with a banebot motor in each side to direct drive each wheel... hook both motors to a Sabertooth dual esc, with the mix on & the steering lead Y'd with the steering servo lead, that might work better than a differential itself & give you tonnes of grunt! ;)

Re: 777 HAUL TRUCK (1/12 size)
 

Hey Joe, yes you can cut plastic on a waterjet, it's cheaper than cutting aluminum or steel!

Cheer's, Neil.

Re: 777 HAUL TRUCK (1/12 size)
 

Joe-I had the dual motor setup in the wheels on my 777. I tried the mixing and it decreased the turning radius by 5" but it would not work in reverse. The wheels would just lock up. Maybe I was doing something wrong but I couldn't make it work. Just thought I would pass this along.

Re: 777 HAUL TRUCK (1/12 size)
 

You were using a Sabertooth esc too Tom?

I wasn't referring to mix in the radio programming, just let the Sabertooth do it's own thing... I've never tried it either, understanding how the Sabertooth works, in theory it should work.

Re: 777 HAUL TRUCK (1/12 size)
 

Yes joe-I was using the sabertooth dual esc. I didn't use the trans. I just flipped the switch to mixing and it worked great going forward but if I tried backing up when I let off the throttle the rear wheels would lock.

Re: 777 HAUL TRUCK (1/12 size)
 

Joe-what I meant to say was that I did not use the transmitter for programming. Maybe that is where I went wrong.

Re: 777 HAUL TRUCK (1/12 size)
 

You didn't make a mistake Tom, you are right. A Sabertooth does the opposite travel in reverse direction, so it would not work as a differential in reverse. On a tracked machine, turning tx stick rht, turns the model rht by speeding up left track/slowing down right track (clockwise rotation), but with reverse travel the left track slows down/right track speeds up to continue turning model clockwise.

However, the Servonaut dual esc with its mixer on would maintain the same arc for/rev, so it would be ideal dual esc to make a functional differential between two motors in a tube axle... although I'm not sure if Servonaut has multiple dual escs with the higher amp ratings.

Leimbach's dual esc is the same as the Servonaut, and being that I have a couple of them in the Stahl tracked equip & a couple of other tracked equip running Sabertooth, it can be mentally confusing to run each model fluently... almost everything is Sabertooth now to keep the function the same for every model.

The only thing that would be necessary for radio programming with the Servonaut is limiting the servo travel % of the ch associated with the Servonaut's steering to + -50 b/c greater than that will make inside motor while turning try to rotate opposite direction.

That's why I like the Sabertooth in tracked equip (especially track loaders), you can spin the tracks on its axis without any for/rev travel.

Re: 777 HAUL TRUCK (1/12 size)
 

The waterjet can cut plastics and many other things like alm.,stainless,tool steel,marble,granite,wood,acrylic,rubber etc etc...not much it can't cut...

http://waterjets.org/index.php?optio...d=46&Itemid=53

Not sure on the cost for a sheet of styrene but a sheet of 12ga(.105") hot roll steel is about 100.00 CAN$

The little banebots motor/gear box could be a weakness in this build, even though is is small it has huge power...about 50 ft-lbs of torque with the 540 motor (yes 50 foot pounds) Banebots suggest limiting the torque to 35 ft-lbs but I will use it without a slip clutch for now. I will be adding an outer bearing to the output shaft to help support the load, which will help solve one possible problem and time will tell how the gears in the box will hold up under that much torque......

http://banebots.com/pc/P60K-S5/P60K-4444-0004

I did consider using two motors in the rear axle housing/tube much the same way as "modelman" used in his 777 truck which is a great idea!! Just couldn't find anything that would fit and be able to support the load at the same time.

Here is a useful tool for calculating motor /torque sizing....

http://www.robotshop.com/blog/en/dri...zing-tool-9698

Re: 777 HAUL TRUCK (1/12 size)
 

Still trying to solve the tire problem....getting the tires foam filled up here just isn't going to happen....too bad because it would be a good solution to eliminate using the tubes and seeing the valve stems. Soooo I have decided to use the tubes in the front and inside rear tires and have the valve stems toward the inside, the problem is that the outer rears tires on the duals will not look the same as the air filled inside tires...what to do?? The simple and somewhat funny solution might be to use "racquetballs" to take up the space and hold the tire to the rim.....this is either really simple or really stupid...lol...but I'm going to try it and see how it works??!!:D

[IMG]http://i1291.photobucket.com/albums/...ps38b8f5f5.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...ps2194f7e0.jpg[/IMG]

[IMG]http://i1291.photobucket.com/albums/...ps4ef33c56.jpg[/IMG]

Re: 777 HAUL TRUCK (1/12 size)
 

Kool idea!

Re: 777 HAUL TRUCK (1/12 size)
 

Have you considered "beadlock's" and making the tire's tubeless?? silicone the 2 halves (rims) together. Weld up the big holes and use smaller short valvestem on the inside. Run a hose between the inner and outer tires.
Yah, more stuff to make you scratch yer head.
Never thought about racket ball's? let us know how they work.
Cheer's, Neil.

Re: 777 HAUL TRUCK (1/12 size)
 

Cool idea. I have seen guys use tennis balls in Honda 50 tires before. I could make a comment on the color of well, you know:rolleyes: but I wouldn't want anyone to be offended...

Re: 777 HAUL TRUCK (1/12 size)
 

Time will tell how well it will work.....and yes they are blue...:lol:

Re: 777 HAUL TRUCK (1/12 size)
 

Some times we just can't find the right product to fill our needs. That's when we need to think out side the box cool idea

Re: 777 HAUL TRUCK (1/12 size)
 

Funny you should mention bead locks....tryed that...kinda....I cut some UHMW plastic spacers to help hold the tires to the rims, originally I hoped the tires alone would be enough to hold the weight but the side walls of these cheap tires are just too thin...:(

[IMG]http://i1291.photobucket.com/albums/...ps6c005b87.jpg[/IMG]

Re: 777 HAUL TRUCK (1/12 size)
 

Thanks....it's hard to believe how well they fit in these tires, almost like they were made for it...I also thought of getting some rubber fuel line and rolling it in the tire to fill the space and help hold it in place. Finding a simple solution to a problem can be challenge....and then when you find the solution you almost can't believe how simple it is and then you wonder why it was so hard to figure out!!??:)

Re: 777 HAUL TRUCK (1/12 size)
 

Well I confused beadlocks with screwing the tire to the rim :mad::mad::mad:, what about a backup ring inside the tire bead to take the screws? Yah blue balls are simpler :p:p:p they're the right color for being overloaded :lol::lol::lol:

If I understood customs a little better, I would offer to send the tire's into get
"stuffed"

Cheer's, Neil.

Re: 777 HAUL TRUCK (1/12 size)
 

Hahaha! Good one Neil!

Re: 777 HAUL TRUCK (1/12 size)
 

:lol::lol::lol::lol:
Thanks Reg :D