1:50 Dragline

[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

[Rvjimd]

MM,

We are definitely on the same page. I enjoy the hobby because I like looking at it from the perspective of the real thing. I imagine how it would look and operate if it were found someplace for real.

The very first thing I noticed in the video is the double bridal. I might give that a try. Not sure if my bucket is quite the correct scale for that setup, but I think it would let it pivot more freely. It hangs up on the chains on the side of the bucket frequently.

I notice he never sets the bucket down completely as he starts bringing it in, is that to keep some tension on the hoist, or the way he is trying to get only material from the slope and not at the low point?

I've been standing here in the shop watching the rest of that video, reall mesmerizing. Sounds eerie. And looks like they might be on the moon.

I. Going to see if I have room to get another motor in there to turn the flywheel gear. It would look really COOL!

Thanks for the help!

Jim

[modelman]

Rvjimd-glad to here you are willing to learn and experiment. Draglines will soon be gone in this country and a lot of kids will grow up and never see one operate. The "double bridal"-I'm not sure what you mean unless it is the-2-drag cables coming off the drum. If so, some operators say the machine runs as stable with one cable as the ones with two. I think the smooth movements come from the operators hands and not the machine. As far as the bucket setting down I think each operator uses different techniques and in some cases they are working so far away maybe they cannot see well enough. Here is a great video made by 9W from inside the cab. You can see how far away they are working.
http://www.youtube.com/watch?v=O_Pic...m4jfg&index=59
On some of the older machines with old controls they are not as responsive as the newer one. Notice on the right hand controller(hoist) how much he is moving the lever back and forth.

[Rvjimd]

That's interesting to watch. I couldn't figure out which was which for a while. Is he running swing with his feet then?

Jim

[modelman]

Yes-some of the newer draglines have all controls on the joy sticks but most of the older ones have swing pedals. I tried to find swing pedals for my dragline but gave up after searching for awhile. They are very hard to find. You really need to know someone who is tearing an old machine down for scrapping and let them get you the pedals.

[Rvjimd]

MM,

what can you tell me about two rope clam shell buckets?

I'm planning on a scratch built or possible another conversion for use as a barge unloader.

At first I thought, simple huh? But if the hoist is lifting the bucket how is the second rope managed so as not to go slack?

Jim

[modelman]

Rvjimd-If you are thinking of another project I guess you are hooked on this great hobby. But I'm sorry to say I know nothing about clamshell buckets or rigging. There is a guy on here that goes by "eef" who has an amazing clam shell crane and bucket and he seems to know how and why everything works. I am sure he would answer your questions. Here is a link to his build-
http://www.rctruckandconstruction.co...ead.php?t=1619
A few pages in there are some good pictures of his clamshell bucket.

[Rvjimd]

Wow, that American Crane is NICE!

[Rvjimd]

I got the big gear in the right side of the cab turning. That's FIVE servos running the crane now. One of them is in the undercarriage.

http://youtu.be/y8jwaB151Gk

Jim

[RCKiwi]

I love seeing that big white gear spinning - gives it some real mechanical scale. Excellent!

[MattDk]

Looking super good.

Do have any close up pictures of your final setup?

/Mario

[Rvjimd]

Thanks for looking guys!

Matt, I don't think I got and pictures, seems like I spend as much time working on the crane as I do loading sand.. so, when I have it on the bench again I will get some pictures. It worked out ok, made brass brackets for all the servos and one drum shares a bracket with the large gear servo. Both drums are now attached directly to the servos.

Jim

[Jared]

That's looking real good, Jim, especially with the spinning gear. If you don't like the way the bucket hangs when dumped you can also play with the length of the drag chains. It looks like they may be a little short. I think ideally there would be a little slack in them when the bucket is fully dumped so they don't slam on the arch every time you dump.

Clam buckets are interesting to build since the geometry changes as it closes. When I designed mine I went for simplicity and looked at a lot of pictures to see how different buckets are built. Then before I started cutting metal I made a side view of the bucket and cut the parts out of cereal box cardboard and made a mockup to check the geometry so I could see if there was going to be any binding or interference with anything. I think I had to modify it a couple times before I was happy with it.

[modelman]

Rvjimd-I really like the latest video! That gear turning adds the final touch of realism. I would also like to see how you rearranged the machinery to get everything inside. Great job!! I agree with Jared-your drag chains look to be a little short.

[Rvjimd]

Ya, I plan on putting longer chains on it. The wife doesn't have much stuff like that in her jewelry box or I would have tried it by now. I was watching a few videos and noticed how they hang better with a bit longer chain.

I guess that is where the expression "how's it hangin?" comes from?

Jim

[kerst]

Originally Posted by Rvjimd

Ya, I plan on putting longer chains on it. The wife doesn't have much stuff like that in her jewelry box or I would have tried it by now. I was watching a few videos and noticed how they hang better with a bit longer chain.

I guess that is where the expression "how's it hangin?" comes from?

Jim

I found some interesting chains at Amazon. there is quite a bit of choice.
Have a look here:
http://www.amazon.com/Stainless-Stee...3367581_b4_6_p
Great project! I also love seeing that big gear wheel turn!

Kerst

[Rvjimd]

Here are a few pictures of the servos inside the cab of my diecast conversion. The last refit included new mounting brackets for drag, house and pivot servos. I was able to stack the hoist and large gear servos in one bracket.





The battery sits there in the open spot. I am using a two cell 850 lipo. I had it out in the photo.



I busted off all the control stick during the mod. I saved them and need to glue them back in place


The brackets are made from brass stock and I simply used CA to glue the servos to the brackets. I scuffed the servos and brackets and get pretty good adhesion. They can still be popped free for maintenance.


Jim

[doodlebug]

Great job Jim! I like it!
Cheer's, Neil.