Tracked vehicle construction?

[EspressoDude]

....just finished the Reverse Phase Coupler (the secret to BioTrak's turning)

Jafe: You are gonna have to do some reinforcing on those flat bars that stick up with the bolts thru them. There will be lots of load trying to pull them together. Maybe a strap from the crosswise tubes in front and back to the tops of the bearing mount strap, them between the tops of them. Sorta hat shaped.

Look waay cool

[Mister Jellyfish Mister]

Ah yes WEAPONS, working on weapons...and SHIELDS!!! The threat of Secret weapons of unimagineable power and devastation require EQUALLY Impenitrable energy barriers and deflection fields...as much as 12 volts can provide!!

Remember BATTLEBOTS total mayhem on batteries!!!

"...The box is locked, the lights are on, it's robot fighting time!!!"

[Elliot]

.
All right... One of you has been out secretly testing your tank! Vee haf pruuf!:




(Tex Avery)

[Tiahaar]

Vee haf pruuf!

Ha! That must be Jaffe out prowling the neighborhood. Mine is kinda landlocked. No way out except in small pieces. So! The dome went on top of TRAK today, everything fits!!! (barely in several places) Admired it for an hour then took it down. Now the tracks have to come off so I can finish running the control cables/rods and paint the frame...a gazzillion little details to grind through. I'm second guessing everything now too, like is the transaxle being overtorqued? Its output turns really slow to drive the tracks...I'd want the chain to break instead of the transaxle case so am changing gears again tomorrow to double output speed & halve torque loads. I've got the gears already to double input speed so it should come out even with less stress on the gearbox. Now if my 3/4" axles do OK (why didn't I use 1"???) and the frame holds together (rod truss seems to work, frame nice and stiff) this thing should slowwwlly roll over everything in its path Bwahahahaha!!


This is the left front dome mount:

View from the top struts looking down; there will be a deck up here to sit on!

And that's about it! Now where did I store those mass launchers and energy emitters????

[capjbadger]

Beautiful.

I should have some pics of my own up tomorrow over in the other mutant vehicle thread.

[dragonfly Jafe]

....just finished the Reverse Phase Coupler (the secret to BioTrak's turning)

Jafe: You are gonna have to do some reinforcing on those flat bars that stick up with the bolts thru them. There will be lots of load trying to pull them together. Maybe a strap from the crosswise tubes in front and back to the tops of the bearing mount strap, them between the tops of them. Sorta hat shaped.

Look waay cool

Thanks for that - now fixed.

Bio Trak is getting quite heavy. Just got a new computer, will post some photos when I get all the software reloaded...

[dragonfly Jafe]

[dragonfly Jafe]

...all 300+ track elements have now been cut-out, deburring and drilling is now my lot in life for the next few days...then on to POWER RIVETING!

[Eric]

wow.
wow.
wow.

That's fucking amazing.

I've been watching you build it via this thread, and I am soooo damn impressed. I can't wait to see it!

[Mister Jellyfish Mister]

Singing:

America!
Fuck Yeah!...

Very pleased indeed to see you use the word "power" before the work "riveter" dear friend. Stave off the carpel tunnel for another year. A new acquisition?

I love the look of the front end!

[dragonfly Jafe]

May I grovel for a tip??? How do you kinetic racers deal with the grease-packed mower transaxles to get the internal resistance of gears/grease minimized? I think I should have just cleaned out the grease and put in a quart of gear oil...

I did this to one differential, and you cannot tell it from the other (with original thicker grease) as far as resistance goes...and I am sure it will not last as long.

[dragonfly Jafe]

Very pleased indeed to see you use the word "power" before the work "riveter" dear friend. Stave off the carpel tunnel for another year. A new acquisition?

I love the look of the front end!

No, my "partner" (Sir Tate) has all the one-use tools I could hope for. And all he wants is a few pieces of coloured paper that are useless where I live. Amazing!

[robotland]

Singing:

America!
Fuck Yeah!...

Very pleased indeed to see you use the word "power" before the work "riveter" dear friend. Stave off the carpel tunnel for another year. A new acquisition?

I love the look of the front end!

....and he's a helluva swordsman, too.

Hey Jafe! Where do the you-know-whats mount? I hope to finish 'em up this weekend....

[dragonfly Jafe]

Hey Jafe! Where do the you-know-whats mount? I hope to finish 'em up this weekend....

I was originally thinking of the rear quarter panel, but maybe the front quarter panels would work better. I am trying to fill up all the horizontal surfaces with stuff to prevent attackers from trying to climb on it (despite BioTrak's massive weight, it does have a few veiled weaknesses)

[Elliot]

'
Regarding grease-packed transaxles;

Somebody discussed this in detail a while ago -- I think it was Bay Bridge Sue.

I have not used mower transaxles myself, but I have four BMW motorcycle trannies. In those I run expensive sythetic motor oil of the thinnest available grade. But I do that just on principle! No idea if science could detect a difference in power loss.

A mower transaxle may not have very good seals, and leakage could be a problem with oil. Look for proper modern lip seals vs rotting strips of leather.

A fresh application of a high quality light grease might be best for a leaky box -- maybe High Temp White Grease.

A friend suggested that for pedal powered applications, I could probably drain the oil from my BMW boxes and never have a problem. But I have had a sealed bearing seize, with obvious signs of heat, on the Pear County Chopper -- which is just a heavy bicycle. So lubrication does matter.

[Lassen Forge]

Put a pan under the drive train / chain train and spray it with WD40 to wash, and paint it with 30 wt daily. Low drag, keeps it lubed. If you're really kewl make a "dip" system where the chain runs into a tin of oil. Like I said, tho, you need a pan to contain the mess you'll be making.

Trans? With seals, run the lightest oil as low as possible (but so it get's sucked up by the gearing). Maybe even rig a splash impeller in the gearbox to make sure oil gets to the bearings. With no seals... pan and encase everything, and oil lightly every day - do NOT keep a resevoir of oil in the tranny.

Or... pull the top case in the morning, and dose the shit out of the bearings with oil, seal it and go for the day.

Grease is less runny out of seals but induces drag, and may not get into the bearings. (Mercedes used 20w-20 motor oil in their transmissions for years... - put 90 wt in it and you cook bearings!) Too light a lube, tho, (WD40, etc.) will wash off or evap and leave your bearing surfaes dry.

Now... if it were me... I'd put this stuff called 600W in the tranny, again just high enough to get picked up. It's thick and gooey (and like a 240 wt viscosity) but it'd not too drag inducing, will crawl steel to bearings, and keep things lubed. Plus it's thick enough to be pretty much held back by seals (still pan off everything and LNT!!) You can get it by the quart at old car outlets (google "Langs Old Car Parts") or through jobbers in 55 gallon drums.

I know it works - Ford "tested" it in 15 million plus differentials and then also used it in gearboxes - and those rear ends are still usable 80 years later.

Hope mine is as good!

bb

[Tiahaar]

600W...I know it works - Ford "tested" it in 15 million plus differentials and then also used it in gearboxes - and those rear ends are still usable 80 years later.

Hope mine is as good!

bb

Ha good one! We ALL can hope for THAT...and fear the reality heheh...some 80 year old rearends are MUCH better than others...or did you mean the steel ones?

Jaffe I think my terrakrawler is feeling intimidated!!! That thing of yours is serious!!!

[dragonfly Jafe]

...wait until I put the turret on!

[robotland]

*barking* FUCKYSHIT!!! Grrrr! POOP!

Oh, wait- I've got my Tourette's on. My mistake.

[dragonfly Jafe]

the main drive sprockets have successfully been machined to fit the chain...there is nothing now that can stand in the way of me and world domination!


(except maybe friction)

[Mister Jellyfish Mister]

Killbuck showed me your turret gun today... you gonna likey!

[Gravity Mike]

It looks incredible!!

I'd be impressed even if it wasn't track driven, or pedal powered!!

I look forward to being shot at.

Gravity

[dragonfly Jafe]

BIOTRAK crawls!

[deviceone]

Video perhaps.....?

yooouuuutube????

[dragonfly Jafe]

I will try to post some video, any tips on how to do that (is it like posting a photo)?

I think I have the de-tracking fixed (the left drive shaft was off-kilter and I hadn't beveled the one side where we removed material...) - I have now travelled over 6 feet (the max distance in my work area) with virtually no effort pedaling. I will definately be able to use the higher gears for greater speed...2 to 3mph may even be feasible!

Another important safety tip for anyone trying to duplicate this design;

When BioTrak rolls (or is pulled) backwards, the pedals on the bikes also go backwards. Probably not an issue on the flat playa, but going up a hill (or up onto a trailer) could result in injury if it started rolling backwards...

[Elliot]

...the pedals on the bikes also go backwards

This is a standard feature of all bicycles and bicycle-based drive trains. You have rolled your bicycle backwards many a time and had the left pedal hit the side stand. Kinetic Sculpture Racers routinely perform a "pedal check" before pushing their vehicles rearward -- making sure there are no people, life jackets, pant legs, gatorade bottles, small children... in the way of the pedals. As for accidentally rolling backwards on a hill...

JUMP!

Seriously, GOOD BRAKES!

[capjbadger]

I will try to post some video, any tips on how to do that (is it like posting a photo)?

Yeah, it's really easy. You just hit upload and pick the video file on your computer that you want. Then you can post the YouTube page URL here for people to go look at.

[dragonfly Jafe]

youtube was down for repairs, here is another site;

http://www.zippyvideos.com/795647975580 ... /*jwaldeck]misc august 006.mov

[Gravity Mike]

This is a standard feature of all bicycles and bicycle-based drive trains. You have rolled your bicycle backwards many a time and had the left pedal hit the side stand. Kinetic Sculpture Racers routinely perform a "pedal check" before pushing their vehicles rearward

No freewheels on the bicycle-based KSRs? I'm surprised, that's how I'm gonna do it. At least, so I think - I'm here to learn!! Now for Elliot's pedal-powered model T sprint car KSR (and some of the others) that's another story.

Gravity

[Elliot]

.
Mike:
Yes, we use freewheels. The freewheel allows you to rest your feet while the vehicle continues forward, such as down-hill. Then the freewheel grabs when you start pumping again.
The Machine does not know if the terrain is up or down. Nor does it know if the frame is going forward or backward. The Machine only knows that the top of the chain is taut in relation to the drive wheel.
Toy with a normal bicycle for a minute and you will see how it works. You just never had occasion to give it any thought before!

I once rode Henry Ford Goes Surfing with no freewheel -- we had jerry-rigged it after a breakdown. Very scary!

Many tandem bicycles have NO freewheeel between the two riders. A six-stitch injury occurred on such a Kontraption last year in Ventura when one rider started pumping before the other was ready.

There is a clever freewheel that can be a problem solver in some situations: Schwinn once made chainrings with a built in freewheel.