Ny-Lint Mobile Dragline Conversion

[Rvjimd]

Just getting started converting my Ny-Lint crane, so here is the conversion thread.

I have a question for anyone with thoughts on the original construction method.

I don't see any obvious spot welds or other signs of how the various steel parts are fastened. Was this old stuff glued or welded or what?

I want to try to keep it looking like the old toy without destroying it in the conversion process. I would love to pop the lid off the back of it for storage and access during the conversion.

http://i1291.photobucket.com/albums/b554/Slotcarjim/8b2e4bd80254578debbac1011a3938b2_zpsb0f03728.jpg



Jim

[9W Monighan]

I see you're starting the flea market buy you picked up . I never fooled with my Nylint crane but most of these are just spot welded together. You may have to find each weld and grind through one layer but that would burn the original paint.. Then you'll be welding up a hole and repainting .of course.

[Rvjimd]

I bought a set of these heli spur gears for this project. Nice to have a good hobby shop in town for all sort of stuff like this, I hate trying to find something like this online. I never know what it will look like for sure and can't tell if it has any chance of working out in a project.

Support your LHS or you will regret it later in life....;)

http://i1291.photobucket.com/albums/b554/Slotcarjim/d97d87cf1b68bcd4c771b8ea4d421423_zpsebfd369c.jpg

Jim

[Stuff]

old metal toys are stamped tin. should be tabs to bend/move etc to open up parts. could be spot welded in places to.

[modelman]

Jim-is it too late to see a picture of the complete model before rebuild starts?

[Rvjimd]

Tom, i think i have a picture of the poor thing before i was let loose on it! :p

http://i1291.photobucket.com/albums/b554/Slotcarjim/8d6e35449dacc20fca5da8e20658e996_zps6b94ea13.jpg

I always like to see progress on build threads, so here is what I have so far and it is only about noon!

I have three servos mounted for drums. The bottom two will be hoist and crowd with lines coming out the front. The third drum is going to go up thru the roof and around a pulley, then up to the boom tip for boom control.

I'm also planning a double pulley down at the bottom of the boom for the crowd line to run thru so I can get the line down low when it comes out to a drag biucket.

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0848_zps4cf85e67.jpg

Jim

[modelman]

Thanks jim-I have not seen one of these This should make a nice project. Is this going to be a dragline only or drag & clamshell ?

[Rvjimd]

Tom,

I am planning to make a drag bucket for it. I would really like to build a crawler undercarrige for it and maybe make it convertable between the motorcrane and crawler, but that is probably a big task and will not happen riht away.

I may try my brass clamshell on it, but I think it will look too small for it.

Jim

[Stuff]

looks good. If you want it self contained (no running wires or power etc through the turn table) put the 4th servo for spinning in the top half there. Did that for my unit crane. works awesome. batteries double as ballast lol

[Trucker_Jo]

Very cool build! Can I see your drum and cable setup? I am building a machine what will have lots of drums and cables and im curious to see how you set everything up! ;)

[Rvjimd]

Jo,

I'm not quite to that point just yet. I just started turning pulleys today and I have find a drill chuck for the tail stock on the lathe before I can center drill them or the drums. I'm not sure if you can tell from one of the pictures, but the drums for the hoist, crowd and boom will be positioned in the center of the "window" right off the gear end of the servos.

You may be able to find more on the unit crane build done by small haul. He has a few pics showing the same sort of thing that I'll be doing.


I hope to be mounting drums in a few days so stay tuned, I am sure to post more pics when I get it to that point.

Jim

[Rvjimd]

I got several pulleys and two rope drums turned on the lathe in the last day and a half. The first drum (the one I stuck in the cab for the picture) is going to be too long, so I turned a shorter one. I support the far end thru the cab and space them somehow.

I'm happy with the pulleys, I am going to need a couple more of them. They are tougher to do than the drums for me anyhow. I don't have any parting tool stock so parting them off is a pain. With the drums, I just start with a section of stock that is just oversized and then I can face it to length.

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0854_zps3f65f264.jpg

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0855_zpsad1473f1.jpg

[Rvjimd]

First video of the Nylint crane! Boom lift goes wrong!

The stick on the first lift is about half, second was full throw. I'm going to do some more testing, not sure if I'm still going to do four part line or maybe just two and use the stock pulley that is on the boom tip now. The thread I'm using is just a bit springy so I need to try some other stuff there.

http://youtu.be/38xs8Tdj9uw

Jim

[modelman]

Looks like you are making some progress jim- I see you are learning the machining side of modeling. It's fun as a hobby but I think you will find that buying tooling is a never-ending process. I have had my lathe for 25 years and I still don't have everything I need but I just get something when I realize I cannot make a part without buying something else. I guess you got lucky on the boom fail. Booms crashing usually cost millions of $$$ :D

[Rvjimd]

Here is a video of the four rope configuration. I need to make bushings and adjust the frame for the cab pulleys and I'm going to move the boom tip location to clear better, but otherwise I like it.

http://youtu.be/Qg0TuI-uW8M

Jim

[TRUCKMAKER]

Jim, this is looking good, I'm following close as I have the same unit sitting on the table waiting to be converted. Won't get done any time soon, there is about 5 projects ahead of it.
So what actually failed, it looked like it spit the boom drum out?

Kent

[Rvjimd]

Ya, I only had it friction pushed onto the servo with no screw or anything to hold it. :)

Jim

[TRUCKMAKER]

Ya, I only had it friction pushed onto the servo with no screw or anything to hold it. :)

Jim

Oops :rolleyes:

[speedy8305]

hey if you want some better line to use try nylon string it's pretty strong but im not sure how much clearance you have around the drum

[Rvjimd]

Making some progress on the crane. Got things aligned pretty good now, found a local supplier for stock so this morning I was able to turn a larger drum for the hoist. I think it will work fine, it is 7/8" stock and I turned the flanges fairly low so the inner diameter is still a bit more than 5/8" which gives me a drum speed that should work okay for the hoist and crowd drums. The larger diameter also helps to hold more rope making the storage of rope fit on one wrap.

I drilled out the top gear on the servos and taped them to 4-40. Then I run a machine screw from the inside of the gear so that is what you see poking out the top. Then the threaded drums screw onto the stud of the servo. This make it easy to screw the drum on or off of the servo for fitting, testing and maintenance.

Thanks go out to Scott (SmallHaul) for all the tips and help along the way!:chug:

And, I love the lathe! What fun! If you have ever thought about a small lathe and you like working on the sort of stuff that brought you to this site, I say go get a lathe.

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0856_zps38c68019.jpg

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0857_zpsed751025.jpg

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0858_zpsae7c8a8c.jpg

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0859_zpsd2e9de7a.jpg

Jim

[Rvjimd]

Video checking the clearance and position of the two low end pulleys for the crowd rope. I'm thinking about making a fair lead for the crowd. If I can position the rope out front and down low, and I can make the holders for the pulleys? I think it would look cool, if I can make one that isn't too far out of scale for the machine.

http://youtu.be/LIUX2lDLoxs

Jim

[bigford]

the dogs like whatever!!! looks good

[modelman]

Looking good jim. Does your lathe have thread cutting capabilities? If so, you could cut laggings in the drums to keep ropes from crawling on top of each other. May not be a problem on this. The fairlead idea is good. All draglines look good with them and they serve a good purpose. Have you considered what scale this model might be?

[Rvjimd]

Tom,

Thanks, I have a bunch of work left to go. I can't cut threads, I think I have the drums set up square enough that the ropes wrap pretty good.

I think the scale is 1/18th.

I'm turning two pulleys for the boom tip and then I'm going to rig it up with my homemade clamshell bucket. You might know my style, I love to get it to a point that it runs, then play with it, I mean TEST it, and then do the finish work.

I am planning to try the fairlead and see how it looks.

Jim

[Rvjimd]

Got the crane pivot servo working. Not completely satisfied with the pinion to servo attachment. I am afraid it won't be long before the threaded bolt comes loose in the top gear of the servo. I did have a nut on the top of it but didn't have enough clearance for the pinion above the truck body, so I had to remove the locking nut. Also the pinion does not fit on the thread of the 4-40 perfectly, so the pinion is not perfectly true and wobbles just a tiny bit.

http://youtu.be/_4BFGXFBoYg

Jim

[bigford]

looks good, are you going to have enough power
to swing when the bucket or clam shell is full of dirt?

[Rvjimd]

BigFord,

Ya, I'm pretty sure it will be plenty. I have the radio turned way Dow to make it smoother and slower looking.:rolleyes:


Been sitting here monkeying with the TX trying to figure out how to engage or disengage the boom control using the throttle cut function. I have the radio programmed as a heli and the boom up and down is on the throttle stick. I can't quite get it to work the way I want. Gona have to dig out a manual I guess.

Jim

[bigford]

good luck with that. I read the manual once only once!!!

[speedy8305]

hey may i ask what is the diameter and thickness of the turntable gear you have there

[Rvjimd]

Speedy,

It is a stock Trex 500 heli main gear. I'll measure it tomorrow. Probably find the specs online. I just grabbed it off the shelf a year ago knowing it might work for such a project,

Jim

[Rvjimd]

Speedy,

The gear measures 3 7/8" x 1/4". It is actually too big in outside diameter for this particular crane but it works. I think perfect would be just big enough to fit around the steel bearing ring on the bottom of the crane house. Also, I custom made the spacer hub for the center to fit the steel center post and cone shaped the outside diameter to center up into the middle of the plastic gear.

The picture doesn't show the top of the rule, but it measures 3 7/8":rolleyes:

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0864_zps215711b6.jpg

In this picture you can see the wear mark on the truck bed where the bearing ring rides. That shows how much too big the new plastic gear is. It doesn't stick out and doesn't look bad so it works for me.

http://i1291.photobucket.com/albums/b554/Slotcarjim/f74774246d363d377903c3e74b09bd0f_zps0af6cf05.jpg

Jim

[Rvjimd]

Here is a short video of the first heavy lift of the crane.

http://www.youtube.com/watch?v=LvqALyTyGYo

Jim

[modelman]

Looks good jim-you seem to have plenty of power and you probably couldn't build a drag bucket large enough to carry that much weight in dirt. However, watching the video it looks like your boom angle will control the amount of weight your carry. That,s okay, you will just have to be careful with the boom when carrying dirt. Keep at it!!

[Rvjimd]

Tom,

Thanks, the truck is pretty heavy and I have good counter weight in the crane so I think it will probably be able to dig with the boom level.:p. The big problem I will probably have will be clearance for the crowd rope around the truck body, even swinging off the sides and rear. When I started mounting the slew ring I was not unhappy to let the crane ride entirely on top of the plastic gear because it give me another 1/4" of height to improve the clearance.

Now, to work on the drag bucket and thinking about how to power the truck.:rolleyes:

Jim

[modelman]

Jim-when you say crowd rope, do you mean the drag rope. If so the correct placement of your fairlead might solve that problem.

[Rvjimd]

Tom, ya that is correct. I will see how it goes and start on the fair lead once I get that far.

Jim

[Rvjimd]

Getting the drag bucket looking good. Hung on the machine to see how the size of it looks. Few adjustments and such and this thing will be moving dirt!

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0869_zpsd372b7fa.jpg

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0871_zpsb05027d9.jpg

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0872_zpsdf7d3f3f.jpg

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0873_zps0cafe306.jpg

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0875_zpsdee91131.jpg

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0874_zpsf198b7b7.jpg

Jim

[modelman]

Nice work jim- smart decision using brass. I used steel on mine and it was really hard to braze all the parts on it. As it got heavier it acted like a big heat sink. Do you know what this bucket weighs? I had to add weight to mine at first but after I got all the mounting points correct the weight was no longer needed. I see you have no adjustments for your mounting points. Hope that works for you but I had problems with this. Watching for the video. You work fast!!

[Rvjimd]

Video...

http://youtu.be/-n7tb6cv77A

[TRUCKMAKER]

Nice job Jim, I only hope mine turns out working half that well!:jaw::jaw:

[Rvjimd]

Modified the drag bucket with a new heavier bottom that integrates the teeth into it, added chains but the are too short, adjusted the dumping line to be a bit longer. (What is the name for the short line that runs from the arch to the pulley and then to the crowd rope at the front of the bucket?)

http://youtu.be/Kbv0GUMWuSU

Jim

[9W Monighan]

Modified the drag bucket with a new heavier bottom that integrates the teeth into it, added chains but the are too short, adjusted the dumping line to be a bit longer. (What is the name for the short line that runs from the arch to the pulley and then to the crowd rope at the front of the bucket?)

http://youtu.be/Kbv0GUMWuSU

Jim

Works nice Jim. To answer your question; "DUMP ROPE"

Playing around with the hoist chains drag chains and dump rope lengths, You will be able to dial it in perfectly for the digging conditions.

[modelman]

Very nice jim-works good and you operate it well also. Looks like you are having a little trouble with the back of the bucket lifting up when loading. You might try lowering the attachment points for the drag ropes on the bucket. Be cautious, a little does a lot. I agree with 9W, just keep tweaking things and you will get it perfect. Another old model survives!!!!

[Rvjimd]

Tom,

Thanks. I have a few more things to do and will continue to adjust things, but I'm very pleased so far! Much easier working on this one compared to my first one that was the 1:50 die cast.

Jim

[Rvjimd]

Now that it seems to be working pretty good, time to finish up.

Added studs to the end of the drums and supported with channel that will be attached to the inside of the cab on the off side to support the drums/servos.

http://i1291.photobucket.com/albums/b554/Slotcarjim/f69548a1e7bdcbc6f853e000b282a237_zpsbb9c87e8.jpg

http://i1291.photobucket.com/albums/b554/Slotcarjim/2abca9c8d27b77ad47b5a4a3159c8a9a_zps58c1298c.jpg

Also turned a bit off the outside diameter of the to large drums and left a small high spot on the inside to reduce the friction on the angle support bracket.

Jim

[modelman]

Looking good jim. A lathe sure is handy!! Have you thought any more about the tracks?

[Rvjimd]

Put some fancy on one of the pulleys. I can't keep away from the lathe!

Turned a shoulder and a center hub and put holes around the center. Should have moved the holes a bit further out. Having fun and learning all the time.

http://i1291.photobucket.com/albums/b554/Slotcarjim/cba1360881f887cbdc08c08c620a177d_zpsb5d3abe1.jpg


http://i1291.photobucket.com/albums/b554/Slotcarjim/07890006814a95f17eadb211320dd8c4_zps7472ae8f.jpg

Anyone have ideas about making a pulley with spokes? I do NOT have a mill. Wonder if there is a way to produce something like that?

Jim

[modelman]

Jim-looks like you are having fun and learning about the lathe. I think a mill is the only way to do spokes. I did it on my mill but it took me a long time-
http://i305.photobucket.com/albums/nn216/modelman/Marion%20Shovel%20build%20picturers/MarionShovelBuildPictures_zps1c355c01.png
Maybe one of the machinist on here will comment on this.

[9W Monighan]

Jim Go to my 9W build thread and look around pages 15-21 or so there are pictures of how I made my spoked sheaves. Here is one but If you look around I have the whole process step by step. I had to make 18 for my boom.
http://img16.imageshack.us/img16/2904/dscn0371nk.jpg

[Rvjimd]

Steve, those are NICE looking!

Question for you machinists - is the order of my steps correct for making a pulley? I want to make two new pulleys for my boom tip and put holes around the outside of the wheel. I know it makes a difference depending on what is being made and with what equipment.

Here is what I think I'm going to do, but half the time (since I'm still learning) I get to a step and realize that I should have something else first or in different order...

Chuck the raw part in the three jaw
Face
Center drill and ream to 1/8" I want a final I'd of 1/8" for the steel rod in the boom tip
Turn the groove in the pulley
Here is where I'm unsure
Add the relief and center hub to the first side
Part off just oversize on the width
Drill the bolt circle holes around the diamete
Put it back in the three jaw, this is where it get tough because now I'm messing up the outside with the three jaw.
Add the relief and center hub to side two

I probably omitted a step here. Should I be using some type of arbor thru the center hole?
I am drilling my bolt circle holes on the vice on the drill press.

Is there some high school machinist text boom that would help me with this sort of stuff?

Jim

[modelman]

Jim-I certainly am not a machinist but I will offer this. If you are damaging your parts with the chuck you may be over tightening the chuck. You will learn as you go but on small parts using less pressure and making small cuts works for me.

[Jared]

One trick is to make a collet that can be chucked in the three jaw. Make it out of whatever round stock or pipe you have. Turn a bore just a thou or so bigger than your sheaves with a shoulder inside a little shallower than the width of the rim. Then slit one side with whatever you have that will make a clean cut. The slit will allow the collet to squeeze the sheave when the chuck is tightened. I whipped up a quick pic with my CAD program but it isn't making it easy to post it.

[Rvjimd]

Jared,

That does make sense. I may have to try that.

[tc1cat]

Since you are going to have the center hole in the pulley, why not put a bolt and nut thru it and hold onto it when you turn the second side of the pulley? This works as long as you make sure to really tighten the bolt that you are putting thru the center hole and take light cuts with your tooling.

[Stuff]

now that does look spiffy!! wow!!!

[Rvjimd]

TC,

I actually have done that on a few parts. I have turned a couple pulleys from bar stock cause I don't have any round big enough, so I cut a square of the bar, drill it and chuck it in the lathe.

Here is a pic of my current mod. Don't want anybody to get the idea I use the lathe on everything now. :D bent some sheet and filing it down to make corner angle for my boom extension.

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0879_zpsdc0dc2d4.jpg

Jim

[Rvjimd]

Got two new pulleys made for the boom tip and a bit more to do to the boom extension.

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0883_zpsc40c5628.jpg

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0882_zps81634c10.jpg

Using sheet stock cut to the lattice shape for the cross bracing.

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0881_zps6b5c1b01.jpg

Jim

[modelman]

Looking good jim-how long will the boom be when done? Your pulleys look spot on too. Did you lay-out the holes free hand? Also, good idea to make the bracing in sections. I did it one pc. at a time and it sure took a long time. How will you attach the bracing, screws, solder, brazing? Keep posting pictures.

[Rvjimd]

Tom, thanks. The pulleys are not perfect but good enough for this crane and I'm always learning something new every time I turn something. I did the layout with dividers, so I mark half way around each side and then drill the last hole between the last two marks that never hit in exactly the correct spot. I have my eye on a rotary table!

I'm not exactly sure how long the boom is going to be. I think my extension is about 5" extra. I eyeballed it trying to make it look good when mounted on the crane. I think it will add a bit of use ability to the machine.

Not sure how I will attach the bracing. My initial thought was standard aluminum rivets but my angle is so narrow that even my smallest rivets are not going to work. I might just use some glue of some sort and try to wedge them in so they are tight.

Jim

[TRUCKMAKER]

Jim, heres the thread I started on mine. You can see how long the extension is. if your interested I'll have to measure it for you later.
http://www.rctruckandconstruction.com/showthread.php?t=7818

[Rvjimd]

Kent,

I had forgotten about yours. That extension looks nice and must be at least twice as long as the one I'm building.

Tom, I checked the boom. My extension is 4.5" and the new total is 27" center to center.

Jim

[Rvjimd]

Getting the boom extension finished up. I saw this sheet metal tip on a YouTube channel I think it was mrpete222. He was cutting sheet metal with a hammer and chisel. I saw it and thought it looked pretty crude and completely nuts. But, I got bored and had to try it! I can't believe how GOOD it actually works, so I made a quick video with some pictures and video of the last section of boom extension.

http://youtu.be/CbCeD10j9hg

Jim

[Rvjimd]

Here is the boom extension installed and painted yellow. Didn't have any blue on hand, not sure what to think about the yellow section?

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0891_zpsa2954843.jpg

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0890_zps920229f1.jpg

http://i1291.photobucket.com/albums/b554/Slotcarjim/IMAG0889_zps28fc2491.jpg

Jim

[Mikem]

Looks great !

[Rvjimd]

Man, this thread is worthless without the photos.:o

Here are a few of them in a video format.

http://youtu.be/h_wDThHiDg4

Jim

[frizzen]

Thank you very much for the montage video!

Do you still have any of the other videos on your youtube account?

[Rvjimd]

Frizz, glad to help out. I think the dragline videos of mine that survived are the new ones of the crawler undercarriage.

Did a bit of work in the shop yesterday, made two pulleys on the lathe and found a fairlead drawing that I'm going to use as an example. We will see how it goes. I'm not sure how I'm going to do it yet? I found an old thread on the die cast forum where 9W milled the one on the 9W from a solid block.:eek:

I was looking at it yesterday thinking maybe making it in two or three parts and bolting it together. I would like to keep the easy conversion from drag to clam if I can.

http://i1291.photobucket.com/albums/b554/Slotcarjim/0733eea41d768ac9522d81bac82b27cc_zpsaxkzc2k1.jpg

Pulleys to check size/scale.

http://i1291.photobucket.com/albums/b554/Slotcarjim/6ad49ca938b6287d66c9f4db33a72a53_zpsvrxvtwm9.jpg

Jim

[Rvjimd]

Question:

Since this thing sort of floats and is able to pivot, should the final rollers be positioned a bit off center high so that the rope would tend to keep the final rollers vertical? In the drawing it looks like it is on center.

Jim

[9W Monighan]

Question:

Since this thing sort of floats and is able to pivot, should the final rollers be positioned a bit off center high so that the rope would tend to keep the final rollers vertical? In the drawing it looks like it is on center.

Jim

My question is the same Jim. But, if you think about it, when the cable dips down or up it goes off center pulling on the wheels rather than the rollers.
Watch some of Bennett Shovels Lima 2400 videos. That machine has the same type as this B-E one. I think the reason for this type is because on these smaller machines the drag cable is whipping around way more than the giant dragline's ropes. Translating into more wear so the load is transferred into both sheaves. The large machines have more space to put larger diameter sheaves on turning slower lasting longer.

[frizzen]

Thanks i only saw it on the truck in a couple videos in a garage with a dirt pile. Killer looking crane.

That's a really slick roller fairlead. I would make a T plate adapter to mount that off the front so 3 fasteners or 2 fasteners and lifting a hook off a lip let you pull it to convert to clam.

I don't think it would need to be offset above or below much since it looks like the larger sheaves are close enough the cable is captive between their edges. How much float do you think it'd take to keep the line smoothly filling the winch drums instead of bunching up?

[Rvjimd]

Friz,

This thread probably has more stuff related to my crane conversion. It is the crawler undercarriage that I made last fall.

http://www.rctruckandconstruction.com/showthread.php?t=10381

Jim

[frizzen]

Do you remember any details about the drag bucket, was it made off any plans or just eyeball? I assume its brass or steel?

Jeremy

[Rvjimd]

Jeremy,

It is all brass from the rack at the local farm store. I can get you some measurements if you want. The bottom is made from a pretty thick piece that was full width (1.5" I think) and I basically found a patent drawing of a bucket that I printed to a size that looked about right for the scale of the machine.

Let me see if I can find the link that I used. One of the photos in the build has the print under the bucket in one shot.

The video at 1:50 shows the drawing I used. I basically used the drawing to match the curve of the bottom piece. Still looking for the link, stand by...

Okay, let's see if this link works...

http://patentimages.storage.googleapis.com/EP0321542B1/imgf0004.png

And this should be the full document...

http://www.google.com/patents/EP0321542B1?cl=en

And mine measures .070" center base plate 2" wide at the mouth and I tapered it a bit toward the rear to make it load a bit better. The sides are about 1" tall and I made them from thinner .035" but they could have also been .070" to add weight to the bucket. I thought about adding wear bars to the under side of the bottom and maybe sides to give it more mass.



Jim

[Rvjimd]

Guys,

I'm trying to improve the crawler on my crane. I decided to try the "Z" style drive tumbler. My question, do the lower idlers help keep the tracks centered?

Here is a pic of what I'm trying to do. Not sure what it is on? Old something?

http://i1291.photobucket.com/albums/b554/Slotcarjim/50e3666d433f4156fb69ab8b733f24be_zps7h79jhtz.jpg

Anyone have any drawings of the idlers for something like this? Why are some like this and other like center wheel and knobs on the driver?

Thanks, Jim

[Rvjimd]

Here is my prototype Z tumbler. Now I'm trying to figure out what to use for the new drive "stubs" or dogs or whatever they are called? The little nub on the track links. I need something a bit wider than the current version.

http://i1291.photobucket.com/albums/b554/Slotcarjim/6aecba89ab17db559d54fd401aa9c344_zpsqtdvjnon.jpg

Jim

[modelman]

Hi jim-good to see you working on the dragline again. I have this one old picture that may help.-
http://i305.photobucket.com/albums/nn216/modelman/Dragline%20pictures/Dragline%20Rebuild/Track%20Idler_zpsjrcfpqlo.jpg
I think most of the old machines drove from the lug in the center of the track pad. You can see in this picture one lug is inside and one lug is outside of the tumbler.

[Rvjimd]

Tom, thanks for the picture. Do you know what brand or age the machine is? I'm curious about when or why they decide to use various style lugs and drive tumblers.

Jim

[Jared]

My question, do the lower idlers help keep the tracks centered?


Yep. And I think the bottom rollers should be spaced different than the spacing of the lugs so the track can't slip around them. That way at least one or two rollers and lugs will always be engaged.


Why are some like this and other like center wheel and knobs on the driver?


My guess is patents. Someone patents one style so the next guy has to figure out his own way. And always there's the quest for a better mousetrap.

[modelman]

Jim-sorry but no I do not know the year or model. Here is another picture. It doesn't help but just shows it is a small machine.-
http://i305.photobucket.com/albums/nn216/modelman/Dragline%20pictures/Dragline%20Rebuild/Track%20Side%20Frame_zpsnaayruv6.jpg
It could be a Koehring, not sure. There is a guy on here named "bartles" that is building a model of a Koehring 305 dragline. He sent me these pictures. Look on page-8-for his thread but he hasn't been on here for a long time.

[Rvjimd]

Progress on the crawler update. I machined a few new drive dogs for track pads and made a new main and center idler wheel. I need at least four more small idlers then I can test the new design.

http://i1291.photobucket.com/albums/b554/Slotcarjim/2a0ba24856d9a3e15e6c25d2d6db3a95_zpsebstawfm.jpg

Jim

[Jared]

Wow, those are some nice track pads! I think you will want to make the sides of the rollers and idler thicker so they don't wear down as fast. Maybe about twice as thick. At least that would be a problem on a 1:1 machine that sees thousands of hours of operation.

[Rvjimd]

Jared,

Ya, you are spot on! Problem is, to do them any wider I will have to move the frame rail out and that changes everything else down there. So for testing, I'm going with it as is. If I like the new tumbler and drive arrangement i plan to widen the rails and make new parts.

Jim

[modelman]

Jim-I like the way you made the lugs on the track pads but was just wondering why you made the tumbler so wide. I'm sure you have a plan. Have you wrapped the pads around the tumbler to see if they will work. I always had a problem with this part. I never quite figured out how to do this. I got close but never got it perfect.

[Rvjimd]

Tom,

They wrap around pretty good, I am hopeful that they might work better than the old style I tried first.

I know what you mean about the width. I may be wrong, but to fit/clear the lugs on the pads I made them as wide as the base of the lug plus the width of the side walls of the tumbler.

Thought I was going to be testing by now but I busted off a 6-32 tap in the tumbler and screwed it up trying to get it out. Darn I hate breaking taps!:mad:

I have a replacement half finished, but got sidetracked the rest of the day getting camping gear ready for the trip out to Brownsville.

With any luck I will get to try one side Sunday.

Jim

[9W Monighan]

Get some #5-40 taps Jim. They are smaller but the finer thread make it easier to tap.

[Rvjimd]

Made some progress this weekend. Here is the new prototype drive tumbler just about ready to go back together for a test. I will make a new wider one with wider side flanges, once I see how it works. I moved the side rail out another 1/4" and made new lower idlers.

http://i1291.photobucket.com/albums/b554/Slotcarjim/e9255157a17991638ae37c65484ffc97_zps2133avpx.jpg

Jim

[Rvjimd]

I am reworking the frame rails for my crawler, but, it has a twist in it. Here is a short video that should explain what I mean.

http://youtu.be/0Eqewf_Ekmc

Part of the reason I wanted to rebuild these parts was the same twist in the old parts. :(

I tried to carefully drill the two sides while clamped together in the mill vise.

I tried to carefully turn the spacers in the lathe. The order was...

Chuck the stock in the 3 jaw, center drill, drill center clearance hole to size.
Turn outside diameter down just enough T to make it round and concentric to the center hole.
Part off. I faced one of them to match the length of the first.

I DIDNT machine the inside mating surfaces of the bar stock.

If I loosen the clamping screws a bit and tweak it as I tighten it is better but I want to try and figure
out what I might be doing wrong.

Jim

[ptsg]

Try to check if the bar stock is straight without the spacers and then face both sides of the spacers. I think it is something to do with the face of the spacers.

[Rvjimd]

I'll try that. I might try and put a slight cone shape on the face ends of the spacers so only the outer diameter touches the bar stock. I guess I could set the spacers on the surface plate and try to check if the ends are parallel?

[9W Monighan]

The spacers need to be faced square with each others end You probably chucked them and they were not running true. Then when you turned them around to do the other side it was running out again. Before you do that, try rotating them some so one will counter the other and maybe it will sit flat. Sometimes the flat bar stock will bow when you machine one side only due to surface tension.
All of the "I" beams I made for my dragline had a bow until I machined the other side.

[Rvjimd]

Steve,

Thanks for the tips! I was able to lightly clamp the assembly in the drill vise and then tighten the screws. This seems to allow it to stay flat enough to satisfy me for now.

Here is a video of the first test of the new drive tumbler. I have already started on the other side.

https://youtu.be/MTlgXVtkDjM

Jim

[modelman]

Jim-looks like you nailed it. The tracks are rotating smoothly with no jumping or jerking. Good job. If you still had the twisting problem I was going to suggest you bolt the-2-rails together tightly and see if they laid flat. Sometimes the holes can run-out enough to cause this. If the other side works this good you will be ready to go.

[Rvjimd]

Thanks Tom, can't wait to try it in some dirt! All we have here today is MUD, we got 3.5" of rain in about 4 hour today :o

Jim

[Rvjimd]

Second video of the crawler upgrade test. This is the same bit of video with some slow motion.

http://youtu.be/AYBJFvvS7wY

Jim

[modelman]

Jim-I can't see well enough to see the old tumbler but the new one seems to work perfectly. I like it!!

[Rvjimd]

I'm getting it! Got the upper and lower idlers made, just need to install them and put the track on and side two is complete! :cool:

http://i1291.photobucket.com/albums/b554/Slotcarjim/BBF74BCF-CC89-4E50-9A80-68E97FD45AFB_zps7skowss2.jpg

Jim

[Rvjimd]

Well, that only took about a weeks worth of full time working in the shop! But, it is pretty much finished and I think it will perform much better now. Ball bearings on the new drive tumblers should really reduce the friction and stress on the chains and motors. The frame rails are now 1/4" wider than before and the tumblers and opposite end rollers, as well as the upper and lower rollers are wider to help keep the tracks flatter and support the machine. I changed the tension screws to an external location which is MUCH easier to adjust now.

I took it out in the back yard and tried it in the grass and a dirt pile by the pond. Seemed to work real good. I'm not getting any of the jerking like it did with the old drive tumblers. I think they were just to tight, but I really like the new style. Much easier to make than the old ones!

I want to make a dust cap for the bearing pockets but other than that, I like it! Brownsville will be a great field test for it, I hope we get some good weather, man was it soggy at the spring show!:o

Oh, and it anyone has a thought on it, I would like a better way to finish the tensioner. The way they are now, the brass rod rotates and the tension hold it against the tensioner bolt. Not ideal. I would like to put a collage around the end of the shaft but it can't be threaded, otherwise it would screw into the rod and seize it. I need to see this, guess I'll start searching the inter web...

http://i1291.photobucket.com/albums/b554/Slotcarjim/3d2cd5fc1830c31377f403c31ca830c7_zpsffssumi1.jpg

http://i1291.photobucket.com/albums/b554/Slotcarjim/f058fec2cbc93cb73f3ffcf5acb1cdc5_zpstcxddalr.jpg

http://i1291.photobucket.com/albums/b554/Slotcarjim/3d4c58582de85b555d27fdc6bfebd31f_zps1vlvhp3d.jpg

[modelman]

Jim-sometimes these jobs take way more time than expected, but as long as the results are what you want is all that matters. I don't see a problem with the tensioners. Once you get them set, I doubt if you will need to adjust them unless you plan to crawl this model many many hours. The new track system looks and works great!!! You might consider putting a jam nut on the tensioner bolt in case it wants to move. Just a thought.

[frizzen]

That's looking really nice.

Why not shave the first couple threads off the drive tensioner, and make a saddle to support the axle so the tension screw won't be wearing on it. It already looks like you're wearing away at the brass.

[Rvjimd]

Friz,

Ya, you are right. I just haven't decided exactly how I want to do it yet. I'll probably let it wear fora few hours and see how it goes. The shaft will be easy to replace and I might also make them in steel. But I plan to eventually make some sort of saddle/collar on the shaft. Somehow then I should be able to let the delrin bushing run free on the shaft and hold the shaft fixed with the collars or something.

Jim

[Rvjimd]

Here is a little video making a five hole bolt circle in one of the boom pulleys on the crane.

http://youtu.be/pHBZeMw3kIU

Jim

[frizzen]

That's a really cool manual mill setup!

[modelman]

Interesting video jim-I don't have the digital readouts but I can do the same thing with a rotary table. Your way looks more complicated to me. Do you think there is an advantage in using your method?

[Rvjimd]

Tom,

I have a 3 jaw mounted on my RT so the weight is at or above my ability to safely move it to and from the mill table and most of the time I have the vise mounted so that save me from the change out.

Here is something I learned from watching one of tom liptons videos of a similar topic-

For a bolt circle on a rotary table, the larger the diameter the more potential error introduced if the angle is not perfect. On the DRO, it wouldn't make any difference how large the circle was.

Another way to think about this comes from aircraft VOR navigation. At a radius of 60 miles from the transmitter station, a one degree deviation would put you off course by one mile. That would be a really large bolt circle, so probably not a concern.

Keep in mind that I only pretend to know much about this stuff! :p

Jim

[doodlebug]

Here is a little video making a five hole bolt circle in one of the boom pulleys on the crane.

http://youtu.be/pHBZeMw3kIU

Jim

Thanks Jim, had no idea on what all a DRO will do!
Cheers, Neil.

[frizzen]

It's probably too late to help, but the unknown yellow machine pic you were modeling the new tracks on is a John Deere 690 / 690a

http://www.yesterdaystractors.com/cgi-bin/viewit.cgi?bd=crawlers&th=94405

[frizzen]

Sorry to keep cluttering your thread up, I couldn't tell from pics.. Did you put the swing servo at the back of the house below the drums, or where the operator would sit?

If it's operator seat, still have room for a figure? If it's under the drums, hom much worse is maintenance?

[Rvjimd]

No problem with clutter, you should see my shop right now! :o

My operator sits directly on the swing servo. The height worked out pretty good.

Jim