Re: Dragline Crawler Build
 

Looking great Jim! I like the progress and constant updates. Keeps the interest up!

Re: Dragline Crawler Build
 

Those pads look great, Jim! Keep it up. You're getting me thinking about finishing out the back half of my 40' container so I can set up a my stuff and get working. Be a great winter project.

Re: Dragline Crawler Build
 

Got four side frame rails made and bolted two of them together. Oh, and if I counted correctly, I got all the pads drilled yesterday. Now all I have left on the pads is riveting the drive dogs into the slots. The pads detail never ends! ;)

http://i1291.photobucket.com/albums/...ps9hbwzuim.jpg

Ya, I need to find some better looking hardware to bolt them together...

http://i1291.photobucket.com/albums/...psny1gnxxs.jpg

Jim

Re: Dragline Crawler Build
 

looking good

Re: Dragline Crawler Build
 

Very good Jim, those high production parts sure do get monotonous

Re: Dragline Crawler Build
 

Here is my simple fixture to drill the little sections of channel that get riveted into the pocket in each pad.

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

http://i1291.photobucket.com/albums/...psq75ua9lt.jpg

Jim

Re: Dragline Crawler Build
 

Looking good jim- to me the pads are the most tedious and time consuming job on these types of projects. Once you get those finished you can have some fun milling all the other parts. Are you using a center drill to spot each hole?

Re: Dragline Crawler Build
 

Here is a shot of the micro stop counter sink tool and pneumatic rivet squeezer. I have a bit of aluminum metal work experience and already had these tools, or I would have NOT attempted to do the pads like it did. I countersink the hole in the bottom of the pads to accept the rivet flush.

http://i1291.photobucket.com/albums/...ps5sgk2ts5.jpg

The micro stop is fine threaded and allows adjustment so you can get a perfect depth on the countersink to fit the rivet head. I left them a bit high because I didn't want any extra rivet on the inside to get in the way of the tumblers. And, the little channel parts are so small and the hole clearance is way less than it should be so setting the rivet to standards can split or crack the part. I could have used a soft rivet here but had a bunch of standard.

http://i1291.photobucket.com/albums/...psh32ogsxb.jpg

Here is the rivet squeezer, really handy of you have a lot of rivets to squeeze.

http://i1291.photobucket.com/albums/...pstf8rgak1.jpg

Closeup of the dirt side of one of the pads with the rivet set.

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

Jim

Re: Dragline Crawler Build
 

Nice work jim-it's good to have the tools you need.

Re: Dragline Crawler Build
 

Parting off one of the spacers for the pairs of side frame rails.

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


I changed my side rail design a bit, should have one set finished tonight...:rolleyes:

Jim

Re: Dragline Crawler Build
 

Got enough finished to do a first check of the "scale" of my undercarriage to the crane.

http://i1291.photobucket.com/albums/...psntl794vd.jpg

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

http://i1291.photobucket.com/albums/...pswt9tuarr.jpg

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


Jim

Re: Dragline Crawler Build
 

Just about ready to take a walk

Re: Dragline Crawler Build
 

Your scale looks good to me jim. Are you happy with it? I like the new frame rails you made. Adds strength, which you probably don't need but it helps the appearance. Are you about ready to make a tumbler and see if this works? Keep cranking on those handles. :D

Re: Dragline Crawler Build
 

Thanks Tom! Ya I am pretty happy with it. I did the side over just for a better appearance. I have a hard time visualizing stuff like this so I always end up making something to see how it looks and then usually make one or two more until I am happy with it.

I am hesitating on the tumblers only because I don't want to take the vice off to put the rotary table on and then I know I will be going back to the vice. It really isn't a big deal, but I am trying to do as much as I can before the switch over.

Decided to put a .050" groove in the bottom of the rails to "hold" the lower rollers.

http://i1291.photobucket.com/albums/...psqux9jdks.jpg

Thanks to ALL for watching! :D

Jim

Re: Dragline Crawler Build
 

I know exactly what you mean about changing set-ups. When I got my 2-in-1 machine several people told me I would regret it but the price was just too good to pass up. However, I thought about what I was told every time I was turning something and needed the mill for 1-simple cut and had to change over again and again. Oh well, live and learn.

Re: Dragline Crawler Build
 

More progress shots! Decided to leave the lower roller shafts round and make little clamps for each end. Will attach them with 2-56 cap screws. Made a little die to form the strap clamps. Turned the 3/16" steel rod down to fit a 3/16" brass bushing to go inside the rollers.

http://i1291.photobucket.com/albums/...psdd2nvq4d.jpg

http://i1291.photobucket.com/albums/...psuoran3um.jpg

http://i1291.photobucket.com/albums/...psrxzljvo4.jpg

http://i1291.photobucket.com/albums/...ps1aksaxrf.jpg

http://i1291.photobucket.com/albums/...psxxgz73ay.jpg

http://i1291.photobucket.com/albums/...psipr5s3hq.jpg

Jim

Re: Dragline Crawler Build
 

Looks like that undercarriage will fit real nice underneath the house, Jim. On those rollers, you might want to bevel the edges that will run between the lugs on the track. That way the roller won't be able to catch the edge of the lug, ride up on it and throw the track off.

Re: Dragline Crawler Build
 

Jared,

Good idea on the roller profile. I need to make all of them, the one in the photo is a prototype. I will put a nice big angle on the corner of them.

QUESTION: How tight should the rollers and tumblers fit between the dog ears on the pads? Not sure if they should be close or real sloppy narrow?

Jim

Re: Dragline Crawler Build
 

Very cool! I have always wondered if someone was ever going to build an older track style like this, and it looks like you're knocking it out of the park..

Re: Dragline Crawler Build
 

Looking good jim-that is a nice beefy press you made. I agree with jared on the rollers, just a slight chamfer on the edges should help. I say you need some clearance between tumblers, rollers, etc.. This allows for dirt not jamming the parts. 9W may know something about this.

Re: Dragline Crawler Build
 

Not too much "visible" progress today but I have actually gotten a bunch done. I wasn't happy with the brass pins linking the pads so I decided to try taping 2-56 holes in the outside tabs and drilled a clearance hole on the inside tabs. The only 2-56 screws I had are shown in the picture. They don't look too bad although a bit big looking I think. I ordered some button head and some plain set screws. I will try those and decide which way to go.

http://i1291.photobucket.com/albums/...pssnjx3mcl.jpg

If I had made this decision earlier i think I would have milled the pads such that there was a shoulder in the outside to let the head of the screw sit flush with the outside edge of the pad.

Jim

Re: Dragline Crawler Build
 

How would you make these idler rollers?

http://i1291.photobucket.com/albums/...ps1brs6kxs.jpg

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

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

I need to make 12 of them. I am starting with 3/4" round aluminum stock. They have a taper to help clear the drive dog tabs on the pads. This is one of those things that I look at and think " that shouldn't be too hard", and then when I start making them I end up with two or three and NONE of them are the same. I had been trying to make the taper using the side angle on my right hand turning tool bit, but that is problematic when it comes to doing the second (or left hand side if the part stays chucked up for the entire process, which I think it should). So, now it finally dawned on me, use the compound to make the taper.

My problems are:

Keeping concentricity. (I think I solved this by NOT over drilling the center hole, so that when I pull the stock out, I don't start off on the next part with an off center hole.)

Getting the same length on the shoulders on each side.

Getting the center rib in the center.

I am using my dial indicator on a mag base to move the carriage in as I turn the shoulder.

Should I be doing this with the part chucked once for the entire part? If so, should I be using a left hand turning tool for the left hand shoulder and Turing away from the chuck?

I think this all comes back to one of my very first questions when I got started with the lathe, "how do you know what steps and what order and how to decide what tool or procedure"?

Thanks for any tips or suggestions.

Jim

Re: Dragline Crawler Build
 

Keep the bar chucked through the whole process. Leave enough bar sticking out of the chuck so your tools can do what is needed for say,2 or 4 rollers. Turn the OD , do the step and taper using LH and RH tools, center drill, rough drill, ream to size you need, part off the finished roller making sure the left and right are equal so rib is centered. Now this process will keep everything concentric but don't drill too far because when you have to pull the bar out of the chuck to machine more you will have to face the bar off so it's clean to start another center drill.

Re: Dragline Crawler Build
 

I sorta have the same issue, but am thinking of taking the easy out and uesing some 5mm bearings instead of making lots of rollers as they will sit nicely in my K1 track.
By the way progerss so far is looking realy good.
cheers andy

Re: Dragline Crawler Build
 

Jim-I think everyone would agree on this. Practice is the best tool. Get to know your machine, find out the problem areas and learn how to work around them. You are doing great so far. Keep working and enjoy!!

Re: Dragline Crawler Build
 

Thanks guys! I think I am going to start working on a drive tumbler while I wait on my 2-56 hardware to arrive. I figure if the diameter of the tumblers change so will the idler rollers so better wait on them until I know I have a tumbler that fits the pad links.

Jim

Re: Dragline Crawler Build
 

And now, for something completely different...

Here is my first prototype drive tumbler! Still working out the details.

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

Don't even have the second side formed because I didn't leave enough center hub to hold onto. Back to the lathe...

Jim

Re: Dragline Crawler Build
 

Finally got one tumbler done both sides. I am waiting on hardware so I can assemble an entire unit. Need to have it nearly complete so I can tell what I need to do to the drive dog ears on the pads and the tumbler flanges.

I am pretty sure I am going to need to put a bevel on both, just not sure how much on each. I sure it will be more trial and lots of errors.

http://i1291.photobucket.com/albums/...pszhw2kneu.jpg

Jim

Re: Dragline Crawler Build
 

Hi Jim, brilliant how you learn as you go and sort out the problems as they come. Learning a lot just reading about your trial and errors. Many thanks for documenting the process.

Cheers!
Stephan

Re: Dragline Crawler Build
 

I am planning to drive the crawler with chain and sprockets like a full scale. I am thinking about ordering some of this .1227" plastic chain but it says 14lbs tensile strength. Is that is way to weak! I don't have a good feel for that in this application.

https://www.servocity.com/html/plast...l#.VX7XXXA8KrU

Is it okay to post a link like this or is that a no-no?


I already have some .25 inch stuff, but I haven't found sprockets small enough yet. I'm gona need about 7/8" for the large sprocket at the tumbler and something smaller at the motor.

Stephan, I get a bit out of the process too. The other day I was about to make some more little tabs that rivet into the pads. I was starting to clamp them into the mill vise and remembered that I had that little fixture block. I went to my thread just to recall the size and shape of the block to make it easier to find in my pile of stuff!


Jim

Re: Dragline Crawler Build
 

Jim,
Check this out and see if its what your looking for:

http://www.mcmaster.com/#miniature-roller-chain/=xmuspu

Re: Dragline Crawler Build
 

Jim-your thinking is right on with this. The dia. of the tumbler dictates the size of all the other parts. You may have some work to do on the tumblers but I think you are on top of that. Personally, I would go with the metal chain but finding the really small sprockets may be a challenge. Does the 1/4" chain look too big? You might find something smaller in some clock works sites-not sure. Keep the pictures coming.

Re: Dragline Crawler Build
 

Truck maker, thanks for the link. I always forget about McM for parts. I just seem to get stuff other places.

Tom, the .25 looks okay. Maybe just a bit big but not too bad. The common 10T sprocket would even look okay next to the tumbler but I might have to search for a smaller one on the motor.

http://i1291.photobucket.com/albums/...ps3g0mtemq.jpg

http://i1291.photobucket.com/albums/...pscd31mqmv.jpg

The little pulley I have in the photo is about the size of the smallest sprocket I have found so far.

Jim

Re: Dragline Crawler Build
 

Jim-if the 10-t sprocket is okay for size then maybe you could use the same on the motor. When you get a little farther along you can turn the assembly and calculate the speed you need and get a motor that speed. If you get a slow motor it should have a lot of power. Just a thought- keep at it!!

Re: Dragline Crawler Build
 

Decided to bolt up both sides again so I took a few more shots.

http://i1291.photobucket.com/albums/...psoyw2lm5j.jpg

Shaft coming out the wrong side here, but no problem yet...

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

http://i1291.photobucket.com/albums/...psgti5cm7j.jpg

http://i1291.photobucket.com/albums/...psjwx1dbyn.jpg

Jim

Re: Dragline Crawler Build
 

Slip ring? Has anyone tried a DIY slip ring? I have repaired one on a in motion servo satellite reciever and I am thinking about trying it. I guess I haven't looked online yet to see how much they are and how it would fit into the UC?

One of the things with my particular install is that there "should be" a 1/4" shaft in the center of the bed that the upper house centers and pivots on. This way it matches the truck frame, in case I want to switch back to the highway truck chassis.

Jim

Re: Dragline Crawler Build
 

Look for some # 25 chain, http://www.amazon.com/Koch-7425100-R.../dp/B004HKITHA Just saw a refence, that scooters use it. http://www.electricscooterparts.com/chain25.html I have a 9 tooth sprocket for a project, can't remember where I bought it 25 years ago. http://www.surpluscenter.com/Power-T...1-2742-9-A.axd
Cheers, Neil.

Re: Dragline Crawler Build
 

I got some of my Enco order today and it had some of the 2-56 screws I was waiting on. I think I can shape the ears on the pads and get smooth operation.

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

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

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

Jim

Re: Dragline Crawler Build
 

Those tracks are so cool! I like that old iron

Re: Dragline Crawler Build
 

Jim- isn't it nice to see all that work finally shape into something. Looks good, although that 2nd picture with the close up of the tumbler is confusing to me. The pitch looks good except on 1-pad. That I don't understand. I think all you can do is finish the pads and see if it turns. Hope it works for you!!