Re: 1:50 Dragline
 

Jim,

i did a quick search for 1/48 rc tanks to find a gearbox for you and found this:

http://www.ebay.com/itm/ACADEMY-1-48...item4ac350585e

RC tanks are such a large hobby segment that you could probably find a tiny twin motor metal gearbox in 1/48 too for your dozer.

Re: 1:50 Dragline
 

Great minds must think alike. A buddy of mine that does RC airplanes and slot cars and 1/18 scale sprint cars with me said the same thing. "You need to find a small motorized tank and use the base from that for your crane" :p

I already feel like a cheater by simply converting a diecast, instead of scratching it like the rest of you guys! :o

That dozer I bought is gona be tough though, boy is it small. I may look for a D11, there has got to be more space to work with in the high drive model.

Jim

Re: 1:50 Dragline
 

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.

Re: 1:50 Dragline
 

Well, I got it going, what a project... Lot of little details that seem like they took all day to iron out, oh wait, it DID take all day!

Don't remember if I posted this one, this was the FIRST location of the servo.

http://i1291.photobucket.com/albums/...psff7f5cd7.jpg

I wasn't happy with that spot. It hid the center mounting screw and was in the way for other reasons.

So, I moved it back to where the potential second servo was going to go.

http://i1291.photobucket.com/albums/...ps4d2c6de5.jpg

Here is a shot of the center hole mod to allow the wire up the center instead of my initial plan of the kidney holes. Had to drill the center of a 8-24 rod and then drill and tap the center hole on the crane body. Won't be able to spin but good enough, just need to keep the revs down to about 1 each way. There was no way an audio jack was going to fit, I bought some 1/8 sets at radio shack and it just was to tight to get that to work.

http://i1291.photobucket.com/albums/...ps14eeba66.jpg

And here is a short bench test. I had it on the loading wall, but it got cold an rainy again so no job site video today.

http://youtu.be/2osu07_ULxg

Jim

Re: 1:50 Dragline
 

wow progress!

Re: 1:50 Dragline
 

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

Re: 1:50 Dragline
 

Hi Jim,

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

Re: 1:50 Dragline
 

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

Jim

New edited Barge Loading Video with Crawling Action!
 

Here is my latest video...

http://youtu.be/8ewOhLxsRgc

Jim

Re: 1:50 Dragline
 

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!!

Re: 1:50 Dragline
 

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

New Fast Forward Loading Video
 

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...:o

http://youtu.be/mgIoMDPAq-Q

Jim

Re: 1:50 Dragline
 

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

Re: 1:50 Dragline
 

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 :cool: Jeez, talk about some river monsters :p;)

Re: 1:50 Dragline
 

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!:eek:

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

Re: 1:50 Dragline
 

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!

Re: 1:50 Dragline
 

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

Re: 1:50 Dragline
 

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!!

Re: 1:50 Dragline
 

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!

Re: 1:50 Dragline
 

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.:o

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

Jim

Re: 1:50 Dragline
 

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.

Re: 1:50 Dragline
 

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

Re: 1:50 Dragline
 

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.:o

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.:cool:

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.

http://i1291.photobucket.com/albums/...ps55610672.jpg

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

Re: 1:50 Dragline
 

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!:cool:

Thanks for the help!

Jim

Re: 1:50 Dragline
 

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.

Re: 1:50 Dragline
 

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

Re: 1:50 Dragline
 

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.

Re: 1:50 Dragline
 

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

Re: 1:50 Dragline
 

Rvjimd-If you are thinking of another project I guess you are hooked on this great hobby:D. 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.

Re: 1:50 Dragline
 

Wow, that American Crane is NICE!

Re: 1:50 Dragline
 

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

Re: 1:50 Dragline
 

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

Re: 1:50 Dragline
 

Looking super good.

Do have any close up pictures of your final setup?

/Mario

Re: 1:50 Dragline
 

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.:p. 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

Re: 1:50 Dragline
 

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.

Re: 1:50 Dragline
 

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.

Re: 1:50 Dragline
 

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? :p

Jim

Re: 1:50 Dragline
 

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

Pictures of the current setup including flywheel gear
 

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.

http://i1291.photobucket.com/albums/...ps76d1bcda.jpg

http://i1291.photobucket.com/albums/...ps75b4bf5e.jpg

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

http://i1291.photobucket.com/albums/...ps8e2beca9.jpg

I busted off all the control stick during the mod. I saved them and need to glue them back in place
http://i1291.photobucket.com/albums/...ps0d4f664f.jpg

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.
http://i1291.photobucket.com/albums/...psd7ca4646.jpg

Jim

Re: 1:50 Dragline
 

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