PFB's Vario JD 850D
 

Received the excavator finally and shot some video of it's first time out.

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

I plan to make another video showing the details of the model and also the radio setup I'm using.

Re: PFB's Vario JD 850D
 

Congratulations! You have a very nice model, great video as well, you got the new trackdrive and thats good, the old one sucked!

Looking forward to see more of it, post up some pics! :)

Re: PFB's Vario JD 850D
 

This model looks huge:eek:. And the breakout force is impressive!

Re: PFB's Vario JD 850D
 

"Fra-Gile":D:eek: Thank's for the chuckle! Glad it finaly came.
Cheer's, Neil.

Re: PFB's Vario JD 850D
 

Need to post some photos of it in the "Show Us, Tracked Vehicles" section.

Re: PFB's Vario JD 850D
 

I'll try to get some good photos tomorrow. Been sick last couple days.

Re: PFB's Vario JD 850D
 

A great looking model! Good video footage too, but I'd also like to see some more photos. These are impressive machines.

Re: PFB's Vario JD 850D
 

It looks like you've operated one of these before, pretty smooth, not much track bounce. :cool:

I'm using a Servonaut S20 speed control on the swing. What's nifty about how it works is that it somewhat ramps up the speed & down again so the start/stops aren't so sharp, I'm not shocking the geartrain. It'll help to reduce gear wear to keep your tolerances tight. It's alot of mass that you're swinging, especially if you're not level & stop abruptly on a downward arc.

Depending on the radio you're using, you could probably program your expotential for smoother start/stops too.

Re: PFB's Vario JD 850D
 

I believe this is the first time I've operated an excavator. The big issue I had was how much I was pushing down with the boom as seen in the video. Getting used to the controls too, once I have those down it will be smooth sailing. I can't remember the esc on the swing. I think it's a Schulze unit. It does ramp up and down but will stop abruptly if you stop the sticks too fast. A good point about gear wear. I will program in some curve to slow her down some.

What are your thoughts on the plastic track links Joe? I assumed they were metal and was a little disappointed when I received the model. I've pulled them off a couple times going over some rough terrain (way above what it should be operated on)

Re: PFB's Vario JD 850D
 

I had the same feelings as you about the tracks, i also thought they were metal ones, but i had no issues with them breaking or some serious wear and i run on very hard garvel ground with lots of small rocks and i see minimal wear so far.

I actually asked a CNC guy over on a swedish board how much he wanted to make aluminium track plates for me, he said around $1200 for the compleate bits, if make them in stainless steel he said "double that price"! :)

Are you, Joe intrested in getting some metaltracks maybe i could talk to him again and see if hes up for the task?

Its alot of money but the coolness factor would go way up! :)

Re: PFB's Vario JD 850D
 

Stainless would be awesome. I'm about to start taking some machining classes so I'm going to see if I can't do something about it myself ;)

Re: PFB's Vario JD 850D
 

Previously, my tracks only made a few revolutions before smoking a Sabertooth 2x12, then when I got a 2x25 smoked one of the motors. So my tracks have virtually zero wear to date! lol

And being that my tracks have turned very little, I was surprise to see some of the friction fit wrist pins have moved 2-4mm or so one way or the other. :confused: I wonder if I dribble a bit of blue locktite around each pin if that'll keep them from moving?

Kalle, when you say $1200, is that USD? Aluminum would never last under the weight of this model, too soft. And $2400 for SS is nearly half the price of the entire model!!! :eek:

I'll be doing lots of twisting & turning carving down the remaining part of the south wall, that'll be a good test for the durability of the tracks. ;)


If you find you're skipping a track often PFB, then you may need to tighten them up. Tap out a wrist pin to seperate a track, the idler just pulls out. Using a 7mm deep socket, screw out the locknut till you have about 2mm thread showing with your spring in place. That's where I set mine to just now, there's still a wee bit of give there yet, but hopefully not enough to let a track slip off the idler.

http://img.photobucket.com/albums/v1...202011/002.jpg

Re: PFB's Vario JD 850D
 

Yes that is usd, thats about how much it would cost to get them done, i also thought that alu. would be to soft but wouldnt the alu be harder then the plastic ones?

He also suggested ductile iron as a cheaper alternative but he said it easly rusts and probably wont last long, powdercoat?

Yes for stainless it would double the machining time and so the cost, so its not worth it as long as i wont win on the lottery! :)

Re: PFB's Vario JD 850D
 

I haven't had it apart yet, glad to see the tension can be adjusted. It's just set way too loose now.

Re: PFB's Vario JD 850D
 

I have even changed the springs to stiffer ones, works much better now, have only lost my tracks once since i changed and that was when my friend tryed it for a while.

Re: PFB's Vario JD 850D
 

Re: PFB's Vario JD 850D
 

Hey PFB
I know i'm late,but congrats on your purchase of the JD excavator,enjoyed the vid,hope to see some more soon.Very nice model
Have fun:D
Tommy

Re: PFB's Vario JD 850D
 

these are amazing machines for sure. The ground you were working with in the video seemed to be pretty rough and it didnt seem to have a bit of trouble breaking ground..I wish I had the money to buy one of these,but I just couldnt imagine the look on my wifes face If I told her I was going to spend 5,000.00 on a RC.....

Re: PFB's Vario JD 850D
 

Try doubling that figure and see what her face looks like. Euro conversion to dollar is uber-sad now.

Re: PFB's Vario JD 850D
 

Speedy Delivery!
http://www.greenandcleanmom.org/wp-c...10/mcfeely.jpg

Had some time to do some fab this evening!
http://farm8.staticflickr.com/7220/7...08d9a1f9_b.jpg

http://farm8.staticflickr.com/7236/7...556a9646_b.jpg

http://farm8.staticflickr.com/7242/7...cb21e142_b.jpg

Now to copy this one and make tabs for the axles. Still gotta figure out what tires to use. Thinking RC3WD ZXLs.

For those that don't know what this is... http://www.youtube.com/watch?feature...&v=j1xnR2E-iJ0

Re: PFB's Vario JD 850D
 

I forgot all about this idea.. as much trouble as I am having with the track drives & getting it around, I gotta make myself set too!

Looking forward to seeing how your's turn out. ;)

Re: PFB's Vario JD 850D
 

Way to go Nathan, I'd forgotten all about them.

Cheer's, Neil.

Re: PFB's Vario JD 850D
 

Oh that's great machine! Put some more videos now, I could watch these for hours. These builds here make me want to build one for myself altough I got to finish my last build.

How wide are these tracks?

Re: PFB's Vario JD 850D
 

2.5" wide

Re: PFB's Vario JD 850D
 

Both cradles welded up. Just waiting on wheels/tires now. Believe this will be my first project to make use of the lathe!

Re: PFB's Vario JD 850D
 

Braved the heat last night/this morning to some work on the dollies.

After some brain-storming with Izzy and Trav I used the RCP Crawlers TLT Straight Axle Adapters and cut off the ears. Cut down they offer the perfect spacing for the tire/wheel from the side plate of the dolly.
http://farm8.staticflickr.com/7130/7...9f4bae73_z.jpg

Cut up a washer for work holding and space for the drill
http://farm8.staticflickr.com/7253/7...ac4e3223_c.jpg

Had to turn the taper for the inside of the washer. (Zinc machines like sh*t) Here it is all mounted up to the dolly. A TLT axle fits inside and I'm using the tamiya brass bushings.
http://farm9.staticflickr.com/8150/7...4a84fba1_c.jpg

The 2.2 ZXLs I ordered are way too big. Might go with the 1.9s. (the 2.2s are just going to have to be used on a future build..... ;) )
http://farm9.staticflickr.com/8026/7...d7b1f2fb_c.jpg

Spacing. I may take a bit more off the TLT adapter so it sits closer to the plate.
http://farm9.staticflickr.com/8019/7...83ff4a4d_c.jpg

This has been a good project to learn the ways around my new Taig machines. That machining class definitely helped me troubleshoot obstacles in clamping and indicating parts for better precision. I've never used a rotary table or 4-jaw chuck before. It's time consuming to setup, but it's a great sense of accomplishment for me knowing how to quickly and easily set them up now. Time to let my ideas and drawings become real objects! Very excited.

Re: PFB's Vario JD 850D
 

Good job Nate.

Travis

Re: PFB's Vario JD 850D
 

Looks good Nate!

Re: PFB's Vario JD 850D
 

I could use a seet of them too, if you're game to make another? :D

Looking good so far. :cool:

Are the tires solid rubber? Or are you packing them solid?

Re: PFB's Vario JD 850D
 

Not sure on the tires, hopefully they'll hold some weight stock. Otherwise I'll stuff more foam or plastic bbs in them.

I can make you a set, it'll be after Indy though.

Re: PFB's Vario JD 850D
 

Went with studs into the plate (When a full-scale CAT engineer says so, you do it :D )
http://farm8.staticflickr.com/7255/7...e3c5c082_c.jpg

Capture washer and hub installed
http://farm9.staticflickr.com/8426/7...08d07a97_c.jpg

Fast forward they are just about done. Just waiting on one TG10 axle to arrive to finish the second. Cables are installed and I ended up having to stuff the tires with really dense strips of foam until full.
http://farm8.staticflickr.com/7134/7...7e05defb_b.jpg

Re: PFB's Vario JD 850D
 

If you made those wheels i need a set for my 544j ive been working on converting:D

Re: PFB's Vario JD 850D
 

also you have a lot of shavings next to those nice bikes:eek:

Re: PFB's Vario JD 850D
 

Nope, those are RC4WD they make them in 2.2 and 1.9

Whole garage is dirty. The bikes don't have a chance at keeping clean between sparks flying from the rally car or rc builds.

Re: PFB's Vario JD 850D
 

The track dollies look good, your a mad man Nate.

Travis

Re: PFB's Vario JD 850D
 

Awesome work PFB - they are looking great!

Re: PFB's Vario JD 850D
 

Great success! Just a few tweaks and these are good to go!

http://www.youtube.com/watch?v=p84DrfttK4g

Re: PFB's Vario JD 850D
 

Looks great!

Re: PFB's Vario JD 850D
 

Good job PFB! Now you need to build a truck to use to move it with.

Re: PFB's Vario JD 850D
 

A little bit of Aerosmith & Walk this way!
Look's great, nice job

Cheer's, Neil.