1:50 Dragline
 

Just a quick video of my new dragline. It is a 1:50 Menck M251 that will likely spend most of its time about where the video was shot. I think I will put a sand pile behind the wall and use the crane to load barges.

Has anyone got any tips motorizing something this small? Does NOT need to be RC, and if it works out the motors could be remoted using a cable drive of some sort.

http://youtu.be/uGDkN3aCH8Q

Worst case scenario, it is going to look good just sitting there as a barge pulls up to the wall!

HEEYYY, it is supposed to get near 60 degrees F today and getting better! YYYAYAAAAAA!

Jim

Jim

Re: 1:50 Dragline
 

Hi, Jim,

You could modificate servos for continuous rotation and that gives you a speed control and gearmotor in one compact package that can be plugged directly into the receiver. Or mount your winches underneath a platform that the machine sits on and run the cables up through the center of the swing circle. Just have to remember not to swing too much and get them twisted up. The hard part in either case might be the swing.

I think your pond is pretty neat, especially the locks! I'd like to do that same sort of thing someday but the problem is it would be full of ducks, nutria, muskrats and labrador retrievers. Sounds like your tug has Jimmies in it.

Re: 1:50 Dragline
 

360 degree robotics servos, receiver, 4AA battery pack in there somewhere.

Re: 1:50 Dragline
 

I finally around to rigging the crane yesterday. Took the cab off so I could easily get to the three winding drums. Could not tell exactly how the brake on each drum worked but they work good enough to make me think they would need to be disabled and the servos would need to provide that function. Also, there is not a lot of room in there.

Jim

Re: 1:50 Dragline
 

Hi Jim,

welcome to the Menck community.

To move the drums, i think the construction of SmallHauls unit cable crane will be a very good possibility for this scale.

Best Regards
Wolfgang

Crane Barge and Hopper Barge
 

Finally got a bit more done on the hopper barge and the crane is sitting on two flat tops all tied to the sea wall. I have some video of the tow moving the crane, but can't get it from my SD camera card onto the iPad for upload.

http://youtu.be/hH-ftQtlKSU

Jim

Re: 1:50 Dragline
 

Wow, just finished watching your videos. I love your pond setup and the lock is so cool. I cant wait to see it when your out there dredging gravel from the bottom and stockpiling it in the barge. Again I am very impressed, thanks for sharing.

Also sorry I dont have anything to add to the purpose of your thread, the conversion of the crane, but there are a number of 1/50 crane conversions that can be found on the internet, especially in some of the german forums. I use google chrome to browse them, it does a decent job of translating.

Re: 1:50 Dragline
 

More Progress...

I went to the hobby shop and bought two mini servos and successfully modified one to turn continuously! Ya, I was afraid I would end up with a inert hunk of plastic.

I cobbled up a piece of brass square stock and a wheel collar and got it to turn the hoist drum at a very pleasing speed going direct drive from the servo to the shaft of the drum! So, tomorrow I'm going to see if there is actually going to be room for two or maybe three servos and a battery and RX inside the cab.

I have also been playing with the idea of running a pulley system instead of direct drive. Got to think on both options and see how it goes...

Should be cool if this comes together

Jim

Diecast Conversion
 

Not sure why I didn't put this thread into the diecast conversion section?

If someone can/wants to move it I guess that would be appropriate, it is definately turning into a conversion!

http://i1291.photobucket.com/albums/...pscea03c03.jpg

Jim

Re: 1:50 Dragline conversion FIRST TEST VIDEO
 

I cant believe how good this has turned out! I am going to have just enough room inside the cab for the batt, RX and ESC. :cool:

I really have got to figure out how to slew it! Stay tuned!

http://youtu.be/d69MPI4AerM

Jim

More video
 

Here is a bit more video! Sort of comical at the end, "how the heck do ya run the goofy thing again?"

http://youtu.be/mX2XQnqcviw

What FUN! :p

Ya think I will ever stop playing with it long enough to finish the conversion?

Jim

Re: 1:50 Dragline
 

Rvjimd-I really admire you for taking on a project this small. Having built a few complicated models that were medium in size but they were giants compared to this one. I have really bad eyesight and I promised myself that I would never take on another "small" build. Just a suggestion for the slewing gear. You need a large gear under the base of the model and I think a servo like you are using will work to turn it but it needs to be slow if possible. They make plastic gears for helicopters I think in the 3"-5" range and that could possibly work. Most draglines and big shovels use a gear almost as big as the house. They also make matching pinion gears that you probably could adapt to your servo. Keep at it and post lots of pictures and good luck.

Re: 1:50 Dragline
 

Model man,

Thanks for the comment. I'm with you on the eyesight! Here is a shot of the bench with a lighted mag viewer! I have three of those suckers at each one of me hobby/shop areas!

In the other pic you can se e the cast slew ring. I'm going to try exactly what you suggest, using a rubber wheel on a servo to drive up against the ring. Hard part will be finding space in the cab for the servo, in the right spot!

http://i1291.photobucket.com/albums/...ps5eff9d50.jpg

http://i1291.photobucket.com/albums/...psd1040cb3.jpg

Jim

Pic from today's conversion progress
 

Here are the pictures of today's progress. Disassembly and took the hoist and drag drums out of the carrier bracket. Drilled thru the hubs and screwed thru and into the servo.

Gonna have to edit this after I get the pics moved... Stand by...

Re: 1:50 Dragline build pics
 

Okay, here are the pics...

http://i1291.photobucket.com/albums/...pse4201991.jpg

http://i1291.photobucket.com/albums/...ps7d3d1c7f.jpg

http://i1291.photobucket.com/albums/...psdfd4b068.jpg

http://i1291.photobucket.com/albums/...psb1247c40.jpg


http://i1291.photobucket.com/albums/...psf5ed9296.jpg

http://i1291.photobucket.com/albums/...ps58ba33d5.jpg

http://i1291.photobucket.com/albums/...ps9d5a35ff.jpg

http://i1291.photobucket.com/albums/...ps7062589f.jpg

http://i1291.photobucket.com/albums/...ps019a6706.jpg
Had to notch the drum frame to allow inserting the drums back into the frame after screwing the servo to the drums.

The shaft with the small pinion gear is to become the drive gear running against the ring gear.

I'm loving this, hope you guys enjoy it half as much as I am.

I hope to have it back together and running three channels by tomorrow afternoon!

Jim

Re: 1:50 Dragline
 

Rvjimd-you are making good progress. Wow-this thing is tiny! The pic of the magnified light gives a great size comparison. I could not see which servo you are using but I think mini-servos would fit inside the house but I don't know if they are strong enough to hoist and drag.Could you please post a close up picture of the tracks and drive sprocket. This looks like a well built model so would you mind saying where you got it.

Re: 1:50 Dragline
 

MM, the model is made by NZG, a German company. They are one of the big diecast makers. I got it locally at a dealer that carries mostly ag farm equipment. Ther drive and pads are cast and steel parts. I have actually been thinking about driving the tracks parallel off of the single axel.

http://i1291.photobucket.com/albums/...ps6ffe6d7b.jpg

http://i1291.photobucket.com/albums/...ps57c6b855.jpg

http://i1291.photobucket.com/albums/...psb405448b.jpg


Jim

Quick Update and slew ring question?
 

First, thanks for all the comments and help!

I got the third channel working today! I think I may have had something pressing on the servo when I put the cab back on, because the pinion gear did not line up as good as it had when I originally fit it.:p

And, it is colder that CRAP here in iowa today and SNOWING! We are setting records for late year snow accumulation, man I am sick of winter! So, I did not take any video on the loading wall.:o. And, my brief testing with the pinion not lined up quite right caused a bit of binding and the shaft unscrewed from the servo. I'll be taking it apart to fix that so, if you are still reading....

Is it more common to use a big long chain around the slew ring gear and drive the chain with a pinion, or like my initial attempt of driving the ring gear directly with the pinion?

If I can figure out how to keep an o-ring on the slew chain ring it seems like that might work better? I have a perfect pinion pulley that would work good on the servo, front wheel from a slot car is actually an o ring tire on the rim with a set screw for the shaft! I would just need to fit or modify the ring gear with a grooved slot or ring.

Jim

Re: 1:50 Dragline
 

Hi

I'm new here, and the list of things that I want to make just got one item longer.

With regards to the servos Modelman might be right that you might find a servo that is smaller, that would not stick out, but I got another idea that might solve the problem, let me see if I can describe it in text.

If you took the servos and moved them to the back og the plastic that holds the "wire" and lay them down on top of each other, (if there is room) then they can stick out on each side, and you could make a pulley that goes from the servo to each cable drum. Te system could be made of string, and a positive side effect would be, that when you reach the very end, the string would just slip on the pulley setup, not damaging your servo.

Might workAttachment 2713


Good luck with your build, looking forward to see the end result

Mario

Re: 1:50 Dragline
 

Rvjimd-The standard way is to let the pinion gear run against the swing gear. However I understand you have to do what you can with the room you have. On the pictures you posted,I cannot see what is what.(eyes):eek: Are the servos in the model mini servos? Also I cannot see the detail of the drive sprocket but that is okay. Just keep doing what you are doing and I think you will have an operating model soon.

Re: 1:50 Dragline
 

MM,

the servos I'm using are labeled as micro servos. The way I have it now, the pinion is running against the ring gear. The only trouble I have is that the ring gear is cast as part of the lower track unit and was never designed to be functional, but the teeth seem to match fairly well with the pinion I'm using. My trouble is getting a good fit to hold the pinion in place. I think i can get it, just wondering if a elastic o ring might reduce the tolerance needed with my current method?

Thought I was going to be filming a test by now but still a few bugs to work out.

Jim

Slew Video Menck Dragline
 

Well, I did manage to get one video of the dragline as I tested out the slew function. I was having trouble with the gear mesh of the pinion and ring gear and you see me help it where the mesh is too loose.

Also the drag servo drum loosened up so I got that to look at this weekend.

http://youtu.be/XH6KNlpnH_c

Jim

Re: 1:50 Dragline
 

Rvjimd-I can see in the picture that the ring gear is not a precision gear and with it cast directly against the lower body that will cause a small problem. Is the ring gear out of round or is the problem holding the pinion in position. The O-ring idea could work but everything will have to be perfectly round and true to keep equal pressure on the gears for 360 degree swing. Keep working at it. I think you have done a great job in a short amount of time. Also I think making the tracks work is a great idea. To have all functions working on a model this small is quite an accomplishment.

Re: 1:50 Dragline
 

Made some really nice progress today on the dragline! I machined down another pinion gear, went up one tooth to 19T to take up some slack in the mesh. I also pinched down the sleeve that the drive shaft runs in to take out some slop. This has completely smoothed out the slewing.

Rewired the battery and plug in socket so I can plug into the RX or unplug and use an adapter to charge. So I won't need to remove the battery for charging. I may still remove it and put back the balance plug that I removed.

The BIG thing I did today to improve operation was went to the hobby shop and bought a new DX6i and a small 4ch RX. The 4ch RX fits really nice in the cab!

I tried the two sticks up and down (throttle and elevator) but was not happy with the throttle stick. There does not seem to be any rate control or centering on the throttle stick.:o. So, I changed the drag drum to use the rudder channel instead. That way I get centering and can slow down the rate! Sure wish they had rate control on the throttle like all the other channels!

It is supposed to be a bit nicer here Sunday so stand by for some outside video! I practiced on the indoor dirt pile and thought I was doing pretty good work. Can't wait to get outside tomorrow! Gona have to find some material to load!

Here is a picture of the backyard yesterday! The snow did finally melt today from all the rain!

http://i1291.photobucket.com/albums/...ps4c7a5cec.jpg

Jim

One more time on the pinion gear...
 

I still had bit to much slop in the mesh of the pinion and ring gear so took some pics and video of the fancy turning machine I use for this sort of thing. It is not exactly a computer controlled mill, but you get the idea...

Finished gear after turning down

http://i1291.photobucket.com/albums/...ps22cfbbec.jpg

Installed on the crane
http://i1291.photobucket.com/albums/...psdcd89976.jpg

With the track assembly in place
http://i1291.photobucket.com/albums/...ps9175f09f.jpg

And the video of the turning process
http://youtu.be/7-lkVaW3V-I

And the ops test video
http://youtu.be/CSAW4rwGt5M

Loading barge video to follow...

Jim

Re: 1:50 Dragline
 

Hi Jim,

good idea, well done


Wolfgang

I think the dragline is working pretty good now!
 

Here is the vid of the Menck dragline loading sand onto a hopper barge at the sea wall. Got it working pretty good with the new DX6i.

http://youtu.be/nRH95IXRhQ0

Jim

Re: 1:50 Dragline
 

That is a sharp little crane you rc'd there. Nice work!

i keep looking at 1/48 dozer and cranes to rc. Have you thought of doing a dozer?

The pond is very cool too.

Re: 1:50 Dragline
 

Ya, I am really itching to do a dozer, and a dump truck. Th is is my first conversion of any kind and now they way the crane is working i fell like, no problem... Lets find a few more!:p

Jim

Re: 1:50 Dragline
 

Hi Jim,

this is a very very good conversion, perfect done.

Its only one little mistake: This is not a M251, its a M260. The difference: M251 has 4 roles on each side for driving, M260 five

For all interested Menck fans, the HP of the Menck archive: http://www.menckundhambrockarchiv.de/ , you can read this in german or english

Re: 1:50 Dragline
 

That is some interesting info. I find a lot of different model numbers when I search on Menck cranes! I wonder why NZG calls it a 251? I'm pretty sure that is the model number on the box...

Thanks for the comments!

Jim

Re: 1:50 Dragline
 

Really good progress that you have made.

Btw, for getting the tracks moving, I saw a video where someone used a jack connector for transferring the signal and power for the servos for the track, through the center, that was pretty smart, you might find room for a mini jack, you only need 4 wires, ground power and 2 signal, so that would be perfect match.
Attachment 2724

/Mario

Re: 1:50 Dragline
 

That's great Jim! Ya done good. Certainly sunk the barge down a little. Now you just need another crane with a clam on the other end of the canal to unload it with.

Re: 1:50 Dragline
 

Jared, ya I noticed the barge sink a bit when I watched the video! So, I watched it fast forward, kind of fun watching it sink in as it gets a load!

Mario or anyone, re the video of the phone jack for the slew connection. Do you have a link for me? I want to study this a bit more. I might try to get that done but I'm not sure how to do it. On my crane a single small machine screw goes up from the bottom directly into the center underneath side of the cab. I am guessing I would need to somehow tap this on the outside of that fitting to allow the phone jack to reside in the center hole where the screw is currently?:confused:

Jim

Re: 1:50 Dragline
 

Not sure if this is the exact clip they had in mind, but I know this guy used an audio jack as a slip ring for a Bruder mini excavator conversion. Good job on your conversion so far. Hope this helps.
http://www.youtube.com/watch?v=VNd_DcxEh9c

Re: 1:50 Dragline
 

Finster,

Thanks, i did finally find that one a few minutes back. I helps, but I'm still scratching my head a bit. I think I need to study some of the bigger machines to get a better idea, then figure out how I can do it small scale.

Nice thing, if I get this thing moving, I'm planning on a single drive servo on the solid axel. That will require a bit less complexity.

Jim

Re: 1:50 Dragline
 

Yes that was the video I was referring to.

Here you can find one optionhttp://www.magomhrc.com/en/search?controller=search&orderby=position&orderway =desc&search_query=Ring&submit_search=Search

Another way is this http://www.adafruit.com/products/736

If the mini jack were to work you might have to skip the screw in the middle and just hope the mini jack will keep everything in place.

Doing two servos will not make it that more advanced, it is actually only one more wire, since you share power and ground, between both servos.
You could choose to put the servos in each end instead of next to each other.

If you cut the connector between both sides of the wheels and keep just enough metal to put something like a pinio gear without the gear "cant remember what it is called" to keep the wheel in place. Then you can mount the servos at each end.

I can't figure out how much space you have in the undercarriage, but I have converted a normal servo into driving one of these motors instead, http://www.goodluckbuy.com/micro-dc-...-6v-1-100.html they don't make as much noise as a normal servo.
The conversion is quite easy, I just can't find the link that I followed.
I would also say that if you have the space inside the cabin to use this kind of motor instead, you could have a very powerful low noise setup.

/Mario

Re: 1:50 Dragline
 

Rvjimd-I think you got! It looks good to me. Enjoyed the video loading the barge. As I said before-Great Job!!

Two more pictures
 

I like the barges that are half loaded, sitting all out of wack, high on one end and about to sink the loaded end...

http://i1291.photobucket.com/albums/...psa2511da2.jpg

Real quick video of two more scoops, the last one sends water over the lower corner.

http://youtu.be/rMwlLP2CIX4

Jim

Working on the track drive...
 

Got started on motorizing the tracks on the crane. Going to see how far it can rotate using the kidney shaped holes in the base and cab. I have not yet figured out how to secure the top to the base without the center screw. Not enough stub poking down onto the base for threads, or I would be all over that, using a audio plug in the screw hole.

http://i1291.photobucket.com/albums/...ps81fc8452.jpg

Crown gear and pinion on shaft of the drive servo. Drilled out the hole in the frame and bushed it with 1/8" brass to make a better fit for the axel shaft.

http://i1291.photobucket.com/albums/...ps03bcfa01.jpg

Switch to a smaller crown, and added a lock nut as a jam nut on the threaded rod, up against the spline of the servo.

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

I'm going to try the single servo and drive parallel and see how that works first. I have started the second servo setup, but I will need to cut the shaft on the other end as well to isolate the left from right.

Jim