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Dfab Engineering Trackmaster Dozer Crawler Restoration

Trackmaster Loader crawler Restoration PArt 03 welding repairs

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The master link pin on the Tracks for my Dfab Trackmaster.

I promised a few pics of the damaged track drive sprockets to some friends, so the first pics of this post are just that. Further down I’ll get to some minor welding repairs pre dissassembly.

Stripped and poorly welded repairs by some hack who tried to fix this before me.
Stripped and poorly welded repairs by some hack who tried to fix this before me. Note the oversized bolt they used to try and lock it in place on the stripped shaft. Sadness

As you can see in the above photos, I’m going to have some fun fixing this sprockets. I’m not sure if I’ll weld metal back on nicely, and then remachine, or cut it all off and weld in a new hub, possibly of a larger more standard size. The spines on these sprockets, and the interior torque hub gears are bothe ANSI B92.1 1-1/2″ diameter shaft with 23 splines, 16/32DP and 30 deg angle. This is a standard involute spline that unfortunately does not seem to have survived to this day and age. Both the 1-3/4″ and 1-3/8″ see lots of use still today. I will have to figure out what to do after I see and learn more about the small Dozers drive setup.

The dirt guard had been cut/split by someone.

The roller/tensioner dirt shield had been split or cut at some point. It was definitely snapped in the rear section, the front had signs of cutting. I clamped/levered this back together and welded it up. Both the upper and lower parts are attached solidly to the frame and it wasn’t hard to pull the split section perfectly together. It didn’t really require much work to weld this up quickly with some flux. I added a few small strips to the front section. I primarily wanted to prevent misalignment from happening if and when I choose to take this apart this winter.

Counterweight on the back of Tiny Dozer, my Trackmaster by Dfab Engineering

Above you see the counterweight on the rear of the Trackmaster. some of these had backhoes on them. Mine has a counterweight. Near as I can tell, these are Solid steel/iron bars welded together, not tubes filled. I measured and did the math, this weighs about 650 lbs. I wanted to pull this off for the repairs this winter. To do that I needed to replace the Lifting hook on the top of it.

Test fitting a new lift hook onto the counterweight on the tiny bulldozer

I found some 5/8″ steel round bar in my stock pile of metal, got my bender out, and bent up a U shape out of it. I’m quite sad I didn’t take a picture of this, I have a Harbor Freight Bending tool, I mounted to a hitch so I can put it on the back of my truck. I didn’t have a location to bolt it to the floor in my shop, and wanted an immovable rugged mounting for it. Turns out this 5/8″ round was pretty challenging to bend up using it. It does list 5/8″ as the maximum thickness, and it definitely is after trying this out.

Repaired new lifting hook for the ~650lb counterweight on the back of my Trackmaster loader dozer

It was a short quick fix, but it felt good to have actually made a repair. While I was at it I cleaned up the factory welds, metal finished them flat, dressed the corners/edges a bit and sprayed it with a weld through/cold Galvinizing paint to keep it all from rusting. I want to pull this with the tractor and it’ll sit outside all winter. Don’t want my new repair to rust.

Stay tuned for more exciting Tiny Tank Progress and repairs.

If someone stumbles across this page with any information about these Dfab Engineering Trackmaster Dozers Crawlers, I’d love to know more. I’d be happy to host manuals and or parts catalogs here on my blog if you have them and are willing to share them with me. Please leave me a comment or email me at my website name on Gmail (no dot com there). I don’t check often, but I eventually will get back to you to host the information. Thanks!

Dfab Engineering Trackmaster Dozer Crawler Restoration

Dfab Trackmaster Dozer Restoration – Part 02 Removing The Bucket

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After getting the Dozer home, and a fair bit of driving it around the yard I began the process of working on my tiny bulldozer. Sometimes I call it my tiny Tank. I’ve always wanted a tracked vehicle, and this is just the perfect size for the homestead. It was cold, wintery, and I froze to drive my new Trackmaster bulldozer around the yard for a day or two once it was home. Then I started to fix things, and prepare to bring it inside for the winter.

My Dfab Engineering Trackmaster Bulldozer. It’s technically a Trackmaster loader crawler but I think of it as a Tiny Tank.

For me the first thing that had to happen was the bucket had to come off. I have a small space to work on it in the winter, and though this small loader Crawler is small, it’s not THAT small. The dimensions of the dozer are roughly 40″ wide by 72″ long, and the bucket is 41″ wide, and about 28″ long sticking out in front of that. I wanted to pull the bucket to get the Dozer inside to work on during the snowy cold winter months.

Trackmaster Dozer, front end loader bucket pins

My Trackmaster has two pins on each side for the bucket I marked with a metal punch numbers for each pin to be able to return them to the correct locations in case there’s any unique wear on these pins. Turns out after pulling them all that there is not a ton of wear on the pins, and it likely does not matter much.

Removing the pins on the front end loader bucket, Dfab Trackmaster loader crawler

For how terrible it looks in the photos, it was surprisingly easy to get the retaining bolts as well as the pins out of the bucket. The bucket is pretty heavy, but not impossible to move by hand. I can’t pick it up off the ground, but I can pivot it around. I’d guess it weighs 300 lbs +- 50lbs. it’s nice thick steel construction and fully welded.

Trackmaster bulldozer bucket removed and flipped up.

That’s the bucket off the tractor and flipped up for the winter.

Trackmaster Loader Crawler with the bucket removed from the front end loader.

For the winter, I sprayed all of the pins down with a heavy coat of white lithium grease to protect from corrosion. I also took the time to remove and replace the Zerk fittings. In hindsight I might have left this till spring but it just happened quickly without much thought. The pins are all bushed with nice grooved thick bronze bushing bearings, and there’s nearly no wear on any of the pins or bushings.

After this I’ll show some minor repairs, mostly welding I did to get Tiny Tank ready to come inside the barn and and come apart this winter.

If someone stumbles across this page with any information about these Dfab Engineering Trackmaster Dozers Crawlers, I’d love to know more. I’d be happy to host manuals and or parts catalogs here on my blog if you have them and are willing to share them with me. Please leave me a comment or email me at my website name on Gmail (no dot com there). I don’t check often, but I eventually will get back to you to host the information. Thanks!

Dfab Engineering Trackmaster Dozer Crawler Restoration

Dfab Engineering Trackmaster Crawler Dozer Restoration – Part 01

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This is the first post on this winters exciting restoration project. After restoring the Bridgeport Mill last winter, I realized I enjoy having this sort of project to help get through the long cold winters in the New Hampshire. I’m going to try to keep my posts short, contain photos, and actually keep up posting this time around. I’m bad about sharing the projects, like the bridgeport which has been done for a year now and seen several hundred hours of use as an essentially new Milling machine.

I picked up this little guy, with the help of my most awesome neighbor. He has both a bigger truck and an equipement trailer that allowed us to go get this little guy. He’s in sad shape, but also cost less than my lawn mower. I knew he was in rough shape, but as is often the way, you don’t know what that means until you dive into the project.

This is the tensioner on one side. I don’t know what happened, but suspect someone didn’t know the proper way to get the tracks off and used this openeing they made to compress the spring to allow the master link to be removed to get the tracks off.

Dfab Trackmaster Dozer, stripped drive sprocket shaft splines.

The real challenge for this rebuild is going to be dealing with this one problem. The shafts are to the best of my ability to determine, involute splined 1.5 ” 23T with a 16/32DP 30 deg pitch to B92.1 specs. I’m not certain how I will deal with this until I see how bad things are in the drivetrain.

If someone stumbles across this page with any information about these dozers, I’d love to know more. I’d be happy to host manuals and or parts catalogs if you have them and are willing to share.

Dfab Engineering Trackmaster rear drive sprocket and steering clutches.

Here’s a shot of the rear drive assembly. The Trackmaster I bought uses a hydraulic motor into a 3 speed transmission (that was trashed, more later), from there it transmits power to this rear drive set up via #60 chain with a 13T sprocket on transmission, and a 38T split sprocket on the driveshaft. You’ll learn more about this in later posts.

Dfab Engineering Trackmaster Crawler Loader Dozer #60 drive chain, transmission, and hydraulic motor

The above shows the general state of the machine, filthy, unloved, but largely intact and working. I drove it onto and off the trailer, as well as all about once I got it to the homestead. It’s stuck in gear with transmission issues (wait till you see how bad this was in later posts). Stay tuned for lots more. My little machine weighs in at about 4500lbs according to the badly worn tag on it. I wish the model and other info was still readable. It’s a Trackmaster made by d-Fab Engineering by Fruehauf Corp. Route 202, Montgomeryville, Penna., USA. I can’t find a lot of information about these machines, if you have a better image of this tag please contact me. I would love to have a nice new one made for my machine. I’ll eventually try to use this one to generate new art files to make one. If you share a useful image I’ll make a new machine tag for you as well when I do that.

d-Fab Engineering by Fruehauf Corp Trackmaster Crawler Dozer
Trackmaster made by d-Fab Engineering by Fruehauf Corp. Route 202, Montgomeryville, Penna., USA

If someone stumbles across this page with any information about these Dfab Engineering Trackmaster Dozers Crawlers, I’d love to know more. I’d be happy to host manuals and or parts catalogs if you have them and are willing to share. Please leave me a comment or email me at my website name on Gmail (no dot com there). I don’t check often, but I eventually will get back to you to host the information. Thanks!

Bridgport Mill Restoration, restorations

Bridgeport Mill Restoration: Part 4 Refinishing the Hardware – Black Oxide surface

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I’m skipping ahead in regards to order things happened in the rebuild as many friends are interested in this particular topic and I do not want to write to each of them explaining how it works.

Freshly refinished Turret Bolt in Black Oxide. Contrasts nicely with the Industrial Light Machine Grey Paint.

In addition to restoring the castings and mechanicals on my Bridgeport Milling Machine I scrounged late last year, I needed to restore or replace the hardware. Replacing hardware can get expensive quickly. The hardware on the mill was all very servicable, but very ugly. I opted to clean, polish, and refinish all of the hardware. I am a huge fan of Black Oxide or Blued finishes on steel. While not suitable for exterior applications, this helps keeps hardware used inside from rusting prematurely. Plus, as you see in the photo above, the black hardware contrasts nicely with the Industrial Light Machine Grey paint I used on the castings after stripping them.

degreasing hardware prior to polishing for refinish
Degreasing hardware in a FormWash with Purple Degreaser

Refinishing hardware is a bit labor intensive. Thankfully the Bridgeport uses relatively few nuts, bolts, and washers in assembly. I start hardware restoration by bulk degreasing and washing all of the parts in an old FormWash which agitates the bath and has been modified to heat the de-greaser to better clean components. I use either Simple Green or Castrol Superclean without dilution as a degreaser which works well, especially heated up to about 50C. You can degrease a surprisingly large number of really nasty dirty parts and engine bits in this before you need to change out your degreaser.

The small wire wheel buffer I made from mu parts piles at the start of this project. It’s been priceless in restoring all of the smaller hardware by polishing it to shiny bare metal.

After degreasing, I spend a few minutes on the wire wheel buffer I built polishing the hardware to shiny bare metal. I’m not looking for mirror finish on the parts, but I do ensure no grit, grime, rust, dirt, or burrs remain. I will touch up dings and “Gorilla wrenching” marks with a fine double cut file and rebuff when I find them. I run taps through the nuts to ensure the threads are cleaned out.

polished and wire brushed clean hardware pre black oxide treatment
Post degreasing and wire brush polishing the bolts are shiny bright metal
Furnace oxidation temperature of 300C for black oxide steel
Preheating the furnace to 300C (550-600F) for black oxide coating of steels.

After cleaning and prepping the hardware the next step is to preheat your furnace to 300C. I have a very nice Paragon furnace I scrounged. It was wrecked when I got it due to some experiment gone horribly wrong. I managed to restore and fix this furnace to almost perfect working condition with very little cost. It’s quite large inside and capable of holding temperatures up to about 1100C.

Hardware in the furnace to get black oxide finish restored
Hardware in the furnace turning black.

This is not the modern process of blackening steels that uses salt solution baths. This is more of the DIY, slower old school method. The process involves heating your clean, dry, parts at 300C for an hour or two, then you dunk them in a nice oil. I am a fan of Canola (rapeseed) oil for this dunking. You can repeat these steps if you want a darker heavier finish. This process leaves a nice hard blue-black finish on your steel. The alloy and part size and shape do affect this process a bit. So all of your parts may not end up quite the exact same shade of black. Dwell time and contaminates can cause differences in color as well.

Canola oil for dunking hot steel into in blackening
Use a metal container for your oil bath, 300C steel will melt right through most plastic containers.

I originally saw this process in a video restoration of an old Vise that my buddy Brian shared with me. This is that vice restoration video which is wonderfully put together: https://www.youtube.com/watch?v=U2jNeObHnZY The video is well worth the time to watch as it is very well done.

Finished parts come out very nicely with a hard black oxide coating. They look like new.
There are slight differences in the black levels on different parts. Some due to alloy, and some due to part mass/dwell time I believe. I have not extensively investigated this process and the effect of variables like temperature and time have on the resulting finish.

The newly blacked parts get sprayed with a solvent wash to remove the canola oil residue which might varnish over time. I then liberally coat them with Vactra way oil or a nice 30W motor oil before installing them back into the mill.

You can see the black hardware contrasts and looks great with the light grey paint on the freshly restored castings.

On the mill the freshly blackened hardware looks fantastic. I am glad to share this trick. It is a nice quick way to give old hardware a new fresh look in a restoration. I like that it doesn’t require multiple baths of nasty caustic and salt solutions compared to the modern industrial process of hot or mid temp chemical conversion coating to black oxide.

More hardware in the oven for blackening
Another batch of hardware in the furnace for treatment.