Fabricating a small dozer and looking for supplies

I've wanted a little Struck mini dozer ever since I was a kid and with the machine tools I have now (and the scarcity of the crawlers on the used market), that made the decision to build one from plans an easy one.
The plans I have are of the MD-40 version which looks similar to this:
The bulk of the tractor is made from 10 gauge plate which I'll have laser or water jet cut from .dwf files, and from common bar stock shafting, pulleys, etc.
The plans are pretty detailed but I'm getting hung up on finding the cast iron sprockets they refer to as "22 tooth #55 agricultural chain cast iron sprocket" and the #55 "track" chains which act as track rails. The plans also list a "heavy duty" chain as being available in the same #55 pitch which I would rather go with than the ligher duty version.
My question is, do you guys know what the current equivalent standard designation is for #55 chain and sprockets, and where I might be able to source them. Googling around turns up a lot of hits to Chinese sites but I'd rather source something locally. The #55 chain used also has tabs on every link that the track shoes bolt to, with holes at 2 inch on center.

Sounds like saw mill chain would meet your needs. If you can find an industrial supply house or a salvage yard.

I have always heard it called "flat chain" but had no luck Googling that. If you have any agricultural junkyards around, they might have some as it was uses on all sorts of low speed agricultural applications back in the day.
Can you use pintle chain? It comes with all sorts of link styles.

looks like the chain on some combining equipment
i'd try a john deere dealer

I am used to working with industrial chain, and I don't recall #55, however my chain catalogues (e.g. Link-Belt, Rexnord) list an agricultural chain with the ISO number "S 55", which is a plain roller chain, no attachment plates. This may be the chain you want, but this is only a suggestion, there are many, many chains out there.

On many chains a "K" attachment is available to give a flat top with holes, and Link-Belt list a "K" attachment for this chain. These have slots .33" wide, not holes, the slot centres are 2.130", but the inner centres of the slots are 2".

The only thing is - in my experience 'K' attachments are very expensive things! So maybe there were other options available for agricultural chains.

I did a Google search on "Link-Belt" 55 agricultural chain and on the first page there was an Oregon supplier offering flame-cut sprockets and chain, I have no idea if they are any good, but they may be able to help:


What about using rubber tracks? Especially if you are going to be using it on a paved surface. Whenever I bring my JD 450C out to the house I put down wood on the concrete so I don't scar up the drive any worse than it is with the tracks.
Also there is another little crawler brand called MagnaTrak (maybe they are one and the same) and a friend of mine had one he inherited, it was maybe twice or so the size as the one in your picture. It was old and well used though and he spent more time working on it than using it. When he finally advertised it for sale he had no problem selling it.

Gaze thru this part of their catalog - chains and sprockets. I didn't see any cast iron sprockets, but I did see what they called "cut teeth" that looked pretty beefy. Look on pages 2 thru 7 of their downloadable catalog. I think pages 6 and 7 have the chain you are looking for. That link above is to that section of their catalog. Baum is great.
Another place= www.martinsprocket.com I didn't see any mention of #55 stuff in their selection, and they are big.

You might want to read through this thread for some ideas.

#55 detachable steel links can be found at http://www.temcoparts.com/ Click chain then detachable steel links.
There are many styles available. They are used in manure spreaders, corn pickers, round balers, etc.
The sprockets sound like wheel sprockets for a manure spreader.
If you are planning to actually do any work with this machine, a more economical alternative is an old 420 or 440 Deere or a small skid steer. You will spend less money and have a more versatile machine. From time to time I see the mini-dozers in trade books. They are nearly worthless to re-sell.
http://lifehacker.com/5066163/farm-s...iy-inspiration is a link to a magazine that my retired Dad takes. Hundreds of ideas, plans, stories about ingenious farmer inventions. No doubt there are several mini-dozer plans in the archives.

Jeremy, what you are looking for is called steel detachable chain among other things. It is often used in pairs with crossbars connecting the two chains for bulk material moving. The floor (apron) of a manure spreader is one application.
Here is an ag supplier with an extensive listing.
This is a formed steel chain that is detached by crimping the chain back on itself and hammering the link out sideways. It predates roller chain by decades. It is definitely a low speed chain, and is why roller chain is sometimes referred to as high speed chain.
On edit: I see Scottie types a lot faster than I do.

"Farm Show" magazine has a lot of home built crawlers. And anything else. Like a 6 cylinder generator hooked up to over 200 microwave ovens so the guy could cut the alfalfa and bale it at the same time.
Agricat, later Agritrac had a good design. Stuck to Agricat is like riding lawnmower to garden tractor.

A more precision alternative would be Standard Attachment chain. No #55 listed though. This would use normal roller chain sprockets.
Here's a listing of sizes - http://diamondchain.com/files/Standa...ach_Roller.pdf

This forum has a category for making a cadtrack it may help.

You should take a walk through a combine salvage yard. Lots of combines used 550 or 557 chain in the feeder throat from the header to the machine. Those feeder chains would have about 5 times the strength of 55 detachable chain. The same sprockets. There would be attachment links every few inches to attach track shoes to. The 550 557 chain are built more like a roller chain. Sprockets from a combine may work, too.

I'm certainly not going to use this as a commercial tractor, it's mostly for fun and to use around the place. I alread have a JD 40C crawler for the bigger stuff. The "track" chain in the specs I have is definitely pinned together and not the detachable steel chain.
It looks like this:

Give these guys a call. Chain is what they do and they are USA. Good folks to work with.

Don't want to hijack your thread, so I'll start another one to show you what I did when I built one 'bout 7 yrs ago.

I'm certainly not going to use this as a commercial tractor, it's mostly for fun and to use around the place. I alread have a JD 40C crawler for the bigger stuff. The "track" chain in the specs I have is definitely pinned together and not the detachable steel chain.

I disagree. I think the chain in your photo IS detachable steel links. You need to visit an AG store. Since this is going to be a novelty machine you could buy a small sprocket made to drive #55, use it for a tooth profile pattern, and have bull wheels burnt from a blank.
On edit, I didn't mean to sound smart alec. Maybe you have the capacity to zoom tighter than I can. From my view this looks just like #55 flat chain that I knocked on and off manure spreaders and corn pickers when I was a kid and Daddy made me farm. The links are available with many different "ears" for attachments.


Buy the tracks and get the other parts too.



An illustration I found has the tracks looking like this:
Definitely a regular pinned-type track.
We found a winner! An exact match for the "tracks" on the dozer:

Are cast iron sprockets for the chains going to wear better than steel considering the fact that they will be in dirt?

Jeremy - looks like you found the proper chain - where did the catalog page come from?

We just threw away a brand new set of rubber tracks for our mini skid steer, the slopes we were working on were killing us with this new set of tracks (kept throwing them off). Our oem set lasted us almost a thousand hours but of course were more than twice as much as an aftermarket set, so of course we tried to go cheap (get what you pay for). After throwing a track about six times we ended up buying the good ones and just tossed the cheap ones a couple of weeks ago. Wish I had'nt thrown them away, you could of had them for shipping.
Sorry for the long story, just had to tell somebody. It never fails, when you have something, you can't give it away and then as soon as you toss it, Well........

If I was going to do this, I would buy a Davis 300 trencher and steal the parts. Preferably a real old one since they have the blade mounted just like a dozer, half way back on the side. Don't buy a 200 as they have a crappy drive. The 300 has a cast iron differential with the track release turning brakes all in one unit. Everything runs hydralic. I have one that is fully operational I would sell for $1000 so you should be able to find one for less for the parts you need.

After further research, it looks like what Struck calls the "Medium duty tracks" are indeed made with the links that you knock together with a hammer (aka used in manure spreaders). The "Heavy duty tracks) use the chain that I linked. The picture was kiped from www.drivesinc.com literature.

I know this was/is an old thread, but I had looked at the old Struck MD-40 plans as well and had some questions. I saw you found a source for the Ag chain, but what about the 22 tooth sprockets? I have not found a source for those anywhere. And the plans also call out a large casting for the shaft and bearing holder on the inside. How did you make that one? An equivalent welding project?
I also didn't see on the plans where the blade attachment would be. I'm assuming it is a manual lift since there are no hydraulics. The only thing I saw on the plans was hitch.
It looks like a fairly easy plan to follow, with not too much fabrication, other than the parts I saw.
I really don't want to start looking in junkyards for sprockets on old hardware, since much of the time something like that might be worn out anyway, and when it does wear out, I'd like a place to get a new one readily.
Thanks for any help.

I burned out my own sprockets for a dozer I built several years ago. I also used: US Tsubaki mining chain and welded ΒΌ'' plates to the chain for track.
mini dozer pics

Nothing to do with your orig. question, but there is a reason the used market is slim on these 'toys'......
If you've always wanted one, it should be a fun project and a neat toy.
If you're thinking it will be capable of doing any kind of work, forget it.....

The photo in the last post shows chain we call double pitch; we had this in the bag house of our dust collector. The chain was on axles with sprockets about 24 inches apart with paddles that moved the dust to an auger. The bag house was 100+ feet long and it ate chain!

Hello Jeremy
Looks like an interesting project. For combine feeder chain & sprockets try
Loewen Premium Quality Combine Parts

Anyone know where I can get plans to build one of these?
This looks like a fun project, http://www.scribd.com/doc/38795064/Vintage-Mini-Dozer-Plans.
Especially if one were to use a larger motor and some hydraulics.

Nothing to do with your orig. question, but there is a reason the used market is slim on these 'toys'......
If you've always wanted one, it should be a fun project and a neat toy.
If you're thinking it will be capable of doing any kind of work, forget it.....

Yes, I agree with you on that. How much can you expect to move with a little light duty thing like the MD-40? I suppose it might drag some logs since I can drag some small ones with just my ATV, and this should have at least as much pulling power, if about 1/4 the speed.
But it has to at least have a blade to complete the looks, even if it does not
move much of any substance.

It is not going to pull (dead load) anymore than it weighs...
That is not much dirt in front with a blade, or a very big log...
Strictly a toy.

Which is perfectly OK for fun and kicks.....make a neat rider for the local old engine shows, etc.
I do think however, that those that were sold, were hyped up as
compact workhorses, which they are not.
Always wondered just how many were sold.....
I think Struck co is still in business.

I got a 1962 Agritrac crawler tractor recently to do some work on my property but it is not going to work out on the steep grades I needed it for, so I am going to sell it. This is the small crawler similar to the MD but a lot stronger. It wasn't running when I bought it but after a carb rebuild, new drive belts, new drive sprocket, new idler bearings, etc., it is running like new now. It has a hydraulic blade and rippers. It has little wear on the drive sprockets and idler wheels and is in great shape over all. It is all original so if you are a collector, this is a good machine to buy. I'm going to ask around $3500 for it. Pics on request.

Got more than enough stuff, but sure would like to see that dozer. Is that the same as the Agri-cat?

Agricat had to change the name because of a dispute from another outfit so it became Agritrac. I attached a pic.



Cool Robert....
What engine?
Any more pics??

I'm certainly not going to use this as a commercial tractor, it's mostly for fun and to use around the place. I alread have a JD 40C crawler for the bigger stuff. The "track" chain in the specs I have is definitely pinned together and not the detachable steel chain.
It looks like this:

that is definetly detachable chain.i can see clearly the square shaped links.my firewood conveyor(old bale elevator)has a similar style of chain but has fingers formed to grab bales.
another term for this kind of chain would be conveyor chain.
the ca550 chain is in fact a double pitch,i wonder if a 44 tooth 50 sprocke would work?
i do recall selling lots of this type of chain,all for ag purposes.

Most use CA550 or CA557 chain. I think the pitch is 1.630"
The sprockets are pretty simple, you can figure out the tooth profile by using the ASME standard for agricultural chain.
All tracks for Struck Maganatrac dozers are made out of CA550 or CA557, the older ones use attachment chain, and have the shoes bolted to every link, the newer Struck tracks use standard chain, and they weld the shoes onto every pin link.
ASME standard, expect to pay too much money to get a copy!!!
B29.300 - Agricultural, Detachable, and Pintle Chains, Attachments and Sprockets
Good luck!

realise its an old thread, but did you end up making the machine.
i found the old plans as well, but, like you, got stuck on some of the parts
many thahks

How about the real thing with a diesel engine. Not 100% sure it may have been CASE Equipment company but i know someone that has all the tooling to build a real working bull dosers that is about 30 inches long. It is a sales deminstrator. It has a real diesel engine. Contact Ken Sergerant at Manchester TN he can get you all the parts to build a real working model bulldozer exact copy of a real bull dozer. He was contracted to build about 100 of these a few years ago.

i have discovered an agricultural chain ca550 with k25 attatchments should be same i have a md1200 struck i have completely restored all thats left is replaceing the track chains has all new belts bearings gears and shafts all stainless bolts will be for sale soon you can contact me at [email protected]

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