AK KRAWLER
Rock Crawler
Those are awesome!!! Man, I wish I had my old Tonka trucks.
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jebster's tonka truck rc conversion
- Thread starter jebster
- Start date
I wish I had all of the ones I grew up with. Some were way beyond recovery. I do keep my eye on Ebay for any good deals. I would like to get a concrete mixer truck for a future build. That would be cool because my dad was a concrete truck driver.
Thanks. I do like working the mechanics on these rigs and trying new things. For example on the crane I may try an electrical slip ring so the crane pedestal can rotate continuously without worrying about wires getting twisted.
Getting very close to done on the scraper. Waiting on a few parts (sprockets) and then it will be a teardown to paint. Gave it a maiden run in the basement and I'm happy with the results.
A short video and some pics.
https://youtu.be/eP2LoU3CDOA
A short video and some pics.
https://youtu.be/eP2LoU3CDOA
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Mike Flea
I wanna be Dave
That's cool, looking forward to seeing it scrape
too cool ive been wanting to do this too so its cool to see some convertions other than dump trucks lol
all i have are dump trucks
so far i have 1 front axle mounted lol
i realy want to do a loader and a excavator but now i want one of those dosers too lol
i cant wait to see the crain truck too that looks fun
after running them are there any mods done yet besides adding some weight or any thing you would do differently
all i have are dump trucks
so far i have 1 front axle mounted lol
i realy want to do a loader and a excavator but now i want one of those dosers too lol
i cant wait to see the crain truck too that looks fun
after running them are there any mods done yet besides adding some weight or any thing you would do differently
Thanks. As far as mods beyond more weight I haven't come up with any. I know they won't work as well as the rc constructupion equipment but that was not the point. I will say one thing that still bothers me is the steering on the loader. It does work but the actuator is very slow so I fine myself being impatient. I will live with it though.
Me too. Once I get the additional sprockets I'll give it a run. Like the rest of these they do work but they aren't that effective. More about the fun of building them and tooling around with them in the yard.
Spent some time working on the crane. Got the rotation, boom winch and bucket winches fired up and working. It is a lot of equipment but it will be tucked in the upper body of the crane. Also installed the slip ring which will allow me to connect the steering servo and the drivetrain esc to the receiver, which will be in the upper body.
I will be running 2 separate batteries because I don't want to run power through the slip ring. One battery will be housed in the upper body and the other in the cab.
So far I have learned two things:
1. I need to use the high gear in the 2 speed transfer case for the bucket winch. The low gear is way to slow.
2. The cheap esc's I bought to drive the rotation and bucket winch aren't programmable the way I want. They don't allow for immediate fwd - rev. That means I have to turn the knob on the controller to do a brake, return to neutral and then it will reverse direction. I can make this work but it may bug me enough that I will eventually upgrade.
A little video of everything in action.
https://youtu.be/WR9RRJl2UlI
I will be running 2 separate batteries because I don't want to run power through the slip ring. One battery will be housed in the upper body and the other in the cab.
So far I have learned two things:
1. I need to use the high gear in the 2 speed transfer case for the bucket winch. The low gear is way to slow.
2. The cheap esc's I bought to drive the rotation and bucket winch aren't programmable the way I want. They don't allow for immediate fwd - rev. That means I have to turn the knob on the controller to do a brake, return to neutral and then it will reverse direction. I can make this work but it may bug me enough that I will eventually upgrade.
A little video of everything in action.
https://youtu.be/WR9RRJl2UlI
Mike Flea
I wanna be Dave
I'm impressed, figuring out how to make each function work would drive me nuts, good job! "thumbsup"
Dakillswitch
Pebble Pounder
Any updates?
I have made a lot of progress but I'm behind on posting pics and videos. I'll try to do that this weekend.
Believe me, it drives me nuts too! Plus, to keep the cost down I'm using a cheap radio so things like EPA isn't an option on most of the additional channels. That means I need to do mechanical alignment on servo throws, which is very time comsuming.
So here are some pics of both the scraper and the crane. Both are done and working. I also posted a couple videos to show them in action.
https://youtu.be/Jq9Lz-nT-LI
https://youtu.be/vZFPV2Ew624
Scraper works great.
The crane works great with one exception. My free spool setup for the bucket to drop is very touchy. In the video I hit the button a number of times trying to get it to drop. Since my radio doesn't have EPA on the extra channels I had to adjust everything mechanically. Probably needs more tuning. Plus I will add a little weight to the bucket so it should want to drop better.
Off working other projects right now but I do have a steam roller and grader on the shelves that would be next in the queue.
https://youtu.be/Jq9Lz-nT-LI
https://youtu.be/vZFPV2Ew624
Scraper works great.
The crane works great with one exception. My free spool setup for the bucket to drop is very touchy. In the video I hit the button a number of times trying to get it to drop. Since my radio doesn't have EPA on the extra channels I had to adjust everything mechanically. Probably needs more tuning. Plus I will add a little weight to the bucket so it should want to drop better.
Off working other projects right now but I do have a steam roller and grader on the shelves that would be next in the queue.
Attachments
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Mike Flea
I wanna be Dave
What are you using for the drum winch on the bucket, I'm surprised it doesn't freewheel when you release it, there should be enough dangling weight from the bucket no matter the angle of the boom.
I like the limiting straps you used for the pivot steer, simple, but effective
I like the limiting straps you used for the pivot steer, simple, but effective
I think the free spool might be having two issues. The line might be dragging on the plastic housing it feeds through so I probably need to open the hole. I also think the transfer case I'm using doesn't cleanly disengage the gears. That is probably a servo travel issue.
And thanks on the limiting straps. They are actually shocks locked un with a little rubber cushion to allow some give as it turns and twists.
I just ran across these builds from your youtube videos. Thank you for the link over here
Awesome conversions! There are definately some great ideas that i'm going to be "borrowing" for some projects! I was looking for some ideas for some 1/16 scale Construction Scraper and Articulated DumpTruck projects im considering
I'm really impressed with the how you did the crane, i had never thought of a modded 2-speed trans to let you drop the clutch to drive the implement into the ground! Have you gotten the release working smooth enough to try 'casting' out past the boom reach?
A while back I converted a 1950s Nylint 'Michigan Crane' that mostly does Dragline work, sometimes Crane work, and very rarely some Clamshell work.
Awesome conversions! There are definately some great ideas that i'm going to be "borrowing" for some projects! I was looking for some ideas for some 1/16 scale Construction Scraper and Articulated DumpTruck projects im considering
I'm really impressed with the how you did the crane, i had never thought of a modded 2-speed trans to let you drop the clutch to drive the implement into the ground! Have you gotten the release working smooth enough to try 'casting' out past the boom reach?
A while back I converted a 1950s Nylint 'Michigan Crane' that mostly does Dragline work, sometimes Crane work, and very rarely some Clamshell work.
Thanks. While they aren't the most capable construction rigs that wasn't the goal. I wanted to keep the Tonka feel while making them functional.
As for the crane I haven't had a chance to get the drop mechanism smoothed out but it is on the project list. I'm sure it is a combo of servo endpoints and having too heavy of a grease in the gearbox (I treated it like any other gearbox which I'm sure was a mistake).
If you have done your on conversions I'd like to see them. Create a thread of your own.
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For your cranes hoist drop, i'd first start with going to a store that has a Fishing section, and getting the biggest sizes of passthrough 'sinker weights' they have. Not the 'kettlebell' or 'wrecking ball' looking ones, try for the Oval, Round, or Egg style with a hole through the center.
Mount it on the line above the lifting hook like the 'Headache Ball' the real ones use.
You want enough weight to keep the line from sagging and help with the cable drop, but every bit it weighs takes away from your lifting payload.
Also if you're running a 'calming line' to the boom to keep a clamshell from spinning, you can use one of the weights instead of trying to do some spring tensioning system
https://youtu.be/g0zSWAf96Qo
My bucket doesn't weigh enough, the calming line doesn't move freely, and if i actually plan to use this bucket i need to make another mode that slaves Crowd (closing) to Hoist o that it's not a huge pain to keep both lines tight when lifting.
If it's still more of a servo travel issue, and there's some room in the model, check out a Servo Stretcher. Little box between RX and Servo with 3 pots to adjust Center and each EPA
Mount it on the line above the lifting hook like the 'Headache Ball' the real ones use.
You want enough weight to keep the line from sagging and help with the cable drop, but every bit it weighs takes away from your lifting payload.
Also if you're running a 'calming line' to the boom to keep a clamshell from spinning, you can use one of the weights instead of trying to do some spring tensioning system
https://youtu.be/g0zSWAf96Qo
My bucket doesn't weigh enough, the calming line doesn't move freely, and if i actually plan to use this bucket i need to make another mode that slaves Crowd (closing) to Hoist o that it's not a huge pain to keep both lines tight when lifting.
If it's still more of a servo travel issue, and there's some room in the model, check out a Servo Stretcher. Little box between RX and Servo with 3 pots to adjust Center and each EPA
Finished up another conversion. Tonka roller. Decided I wanted the drum to be driven vs just free rolling. I think it came together nicely. Wish I could post pics but since I can't I did a video where I tried to show all the mechanics and electronics.
https://youtu.be/GozqI4oPFc4?si=Ev9KPlww-Cy6bsk7
https://youtu.be/GozqI4oPFc4?si=Ev9KPlww-Cy6bsk7
That thing is seriously a work of art and an engineering masterpiece. Fantastic job getting this all worked out and running. Tighter turning radius than I would've expected too. So cool!
I chalk the turning radius up to the drum being very slightly overdriven and a venom creeper axle in the rear. I'm able to lock or unlock the diff. You are seeing it unlocked in the videos.
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