1:50 Dragline

[SmallHaul]

The Acadamy tank gearbox looks to be well made.

http://www.rcgroups.com/forums/showthread.php?t=1355256

Your idea of using a slot.it crown gear and a shaft off the servo is clever.

[Stuff]

wow progress!

[Rvjimd]

Hopefully the weather will be nice tomorrow and I can get some descent video back out at the canal loading wall, with a bit of walking up and down the length of the wall while loading another barge.

Jim

[Seilbagger]

Hi Jim,

very well done. For me this is to small, i would have problems with my big fingers, lol

[Rvjimd]

Even yesterday as I was very close to finishing I thought, "this is too small, what have I gotten myself into?"

Jim

[Rvjimd]

Here is my latest video...

http://youtu.be/8ewOhLxsRgc

Jim

[modelman]

Rvjimd-nice job on a very tiny model! Every thing seems to be working good and with the kind of loading you are doing from the wall you probably don't need steering on the dragline. I would NEVER try a build like this but I have enjoyed watching it all come together. Nice video too!!

[Rvjimd]

I made a bunch of improvements to the crane so now the servos fit inside the cab. I was even able to put the big gear back in the right hand side that shows thru the door. I was having some issues with the plastic a frame structure that held the drums and the slewing servo came loose from the shaft, I figured while I was in there I would do a refit. Can't really see any difference from the video perspective but I had to test it out so, might as well film it huh?

http://youtu.be/NcxPRX6O5lY

Jim

[Rvjimd]

I just put up another loading video. This one I edited on the iPad and did a fast forward. It took about thirty minutes to load the flat top with side boards AND the new prototype.

Hope you guys are not sick of my barge loading obsession yet...

http://youtu.be/mgIoMDPAq-Q

Jim

[tracksntreadslou]

Great Video ..Looks like some giant Red stergon cruisin the river ..good work on the conversion

[YoungGunz]

Love what you are doing here, really unique! Do you have a "project" planned? I would love to see a project start to finish based around the water. I think some dredging would be really cool too Jeez, talk about some river monsters

[Rvjimd]

Ya, all of the gold fish started out life as little tiny feeders that I rescued from the pet store. There are also a bunch of them that were spawned in the pond the first year, so they would be coming up in three years old now.

A few of them are getting pretty big!

As far as a plan. We had a giant oak tree where the small patio is now at the bottom of the stairs. Well, it decided to come down on the house in a wind storm about four years ago. It smashed the deck, and the house. We had to resurface the deck and decided to add the center stairs and brick patio at the bottom. I said, hey, what about a pond? And if we're doing a pond, how about a river section running under the stairs? Cause if we're gona do that, the river should go in before the stairs. And the plan always included a lock chamber to a lower pool. And the entire project for me was about running tow boats and barges thru the lock?

The sand loading and crane just sort of came along naturally.

I need to find some large grit sand blast sand. I am hoping it will dredge better than the general purpose sand I have. I have tried some dredging, but the material sticks in the bucket when it gets wet. The pea gravel is too big and round and smooth and does not scoop up well.

I have also been studying the screener videos that Joe started. I think that if I could screen the sand I have, some of it might be well suited for part of the operation.

Thanks for the comments!

Jim

[modelman]

Rvjimd-I like the changes you made to the dragline. It looks a lot more realistic now especially with the big gear showing thru the door. I notice on your videos you are "tight lining" with this model but with a small machine you can do that. Nice work!

[Rvjimd]

MM,

I'm searching for "tight line" on the web but haven't found a real good description yet. Give me your explanation.

I assume it means the the hoist and drag ropes are never let free to go out or down without brake applied or in gear operation.

I would love to be able to cast the bucket when I dredge but without a complicated clutch system that won't happen. It would be pretty thought to cram that in there, unless someone makes a servo with a clutch built into it.

Thanks for the comment, add to the fun, learning more about stuff like that.

It's fun for me mostly, because my gramps ran a dragline, but I don't remember him too well, he died when I was very young. I can't remember for sure but I think he actually electrocuted himself on the dragline.

Jim

[modelman]

Rvjimd-"tight lining" means carrying the bucket in close to the boom after it is loaded. This action on a real dragline would cause the hoist & drag motors to overheat and severely damage or possibly destroy them. Also remember that they are carrying 100's of tons of dirt with each bucket and this also puts extra stress on the hoist & drag ropes. The correct action is after the bucket is loaded you let out the drag cables until the bucket is swinging freely under the boom-point. Even to the point that you are spilling a little dirt as you swing toward the spoil pile. If done correctly this takes all of the stress off the motors and some off the ropes. If you watch videos of some good operators you can see this is the way they work. After the bucket is loaded they let out the drag cables as far as possible without dumping and then adjust the height of the bucket as they are swinging so they are ready to dump as soon as they reach the pile. It takes a little practice to get all the motions working together but then it is really fun to watch. Also with your ingenuity I think you could make the big gear turn off one of your drums or servos which I think would make the model even more realistic... Have fun!!

[Rvjimd]

MM,

Thanks, very good description. I'll try that, I have been holding the bucket tight just to keep from spilling the material.

Related question for you - is there a perfect length for the tipping line ( is that what the short line is called, going from top of bucket to pulley, to drag rope shackle? I have messed with it about three times trying to figure out what works best. First I made it a bit too long and it would let the bucket tip too early. I have been shortening to get it to hold from tipping. I think when it is too short, the bucket won't hang empty and down properly. Maybe this is not going to come out perfect in such a small scale?

And, about the big gear. From the videos I have watched of full scales, I was under the impression that the big gear turns the same way ALL the time? Or does it reverse direction based on rope direction of the hoist?

I could probably drive the gear from an aux servo and not connect it to anything. It would look VERY COOL if that thing was turning!

[Rvjimd]

MM,

One more question/comment...

I have seen some 1:1 stuff operated as you describe and they really get that bucket swinging! Espically if they are dredging. Is the counterweight matched to the anticipated load, or force involved when they cast the bucket?

I will never be able to get that sort of moves out of my little model just due to the lack of momentum. I don't even think I could get that "look" if I used some slow motion tricks with the video.

Thanks again. I enjoy learning more about all this stuff.

Jim

[FlyingBeagle]

As I have said previously, I am very impressed by your entire setup, the pond, lock, and equipment conversion are awesome.

I have a coupe of questions? Have you thought about building barges out of something other than 2X6 lumber so that they are hollow and can hold more material? Also can you tell much of a difference on the tug when pushing empty barges compared to full barges? Just curious, Thanks again for sharing.

[modelman]

Rvjimd-I wasn't sure if you were interested in this but myself I like to learn about other things. On the drag rope lengths, I think you are doing the right thing by experimenting. Most machines especially models are different. As you have seen the drag ropes affect the way the bucket dumps and carries. I think the correct position for the bucket to carry is with it slightly tilted back when hanging under the boom point but this is hard to achieve on a model because of the lack of weight. Just work with this and get it the way you like and the way it operates the best. Also adding weight to the bucket is good if it makes it work better and if your servos have the strength. On the big gear I think you are correct. They are used on smaller machines and I believe they act as flywheels to keep things running smoothly.You could possibly use a small electric motor to run this gear slowly and continuosly and it would look really good but I'm sure you can work this out. As far as casting I think only some small machines can do that and they must be equipped with clutches and brakes. Where you are working it looks like your boom is long enough so you probably don't need this. Watch this video and you can see that the bucket is almost dumping as he is swinging-
http://www.youtube.com/watch?v=3GX481pFhE8

[Rvjimd]

FB,

Thanks for the compliment and questions!

I actually ripped down the most recent solid 2x6 barge into approx 1/8 slabs and built it up with that. That is the second one in the high speed video. I like the way it works and I just need to decide if I want to make three more the same way. I also plan to finish it out by adding a hollow section around the perimeter by adding false walls around the sides and putting a walkway on that. It would look very similar to the rust color one but it would be an actual hopper. I am in the shop now, and my intention today was to finalize the material and start on three more, but so far all I have done is clean, put stuff away and hang a new light over an unused bench. I'm sure ill get to the barge building process this afternoon! My short term goal with the barges is to have four that look good so I can have a full tow to push thru the lock chamber. Actually six might be a full tow, but there is not enough room on any one of the ponds to do much with that big a tow load.

When I started out with the barge and tow boat thing I knew I wanted a LOT of mass to push so the tow and barges reacted more realistic. It was also VERY easy to test the prototype since all I had to do was cut some 2x6 to length.

You can tell the difference with a loaded barge, empty and empty hopper. The motor in my tow is a Carrera 1/32 slot car motor. I actually used the entire rear end/motor pod from the car which included the axel, crown gear and motor with pinion.

Here is a pic of the setup. I was hoping for an under powered setup to help out with realism, I don't like stuff that looks way overpowered compared to its real life counterpart.



I scratch built the entire boat except for using the drive train from the slot car. Cut the four blade prop from brass stock, and made the stuffing tube and driveshaft from brass rod.

Thanks

Jim