Supporting > Vehicles & Models
Chris' Build of a Lombard Hauler Engine
crueby:
Okay, its time for a big project, and next on the list is a running model of a Lombard Hauler, which was the first commercially successul vehicle with a track drive, back in the early 1900s. They were used in the northern woods (mainly USA, some went to other countries) to haul logs on sleds out of the woods to the sawmills and rail terminals. They were steam powered, using a locomotive style boiler and two double acting engines, one on each side, just like a locomotive, but rather than drive wheels that had a track mechanism on each side and runners at the front (runners could be switched to wheels for moving when no snow on the ground). Here are pictures of from the original patents of the engine and the track system:
as well as a picture of one in use:
Note the steersman at the front - he could control the runners as well as an optional plow blade at the front. He could communicate via a bell rope or whistle back to the engineer in the cab. No brakes, so sometimes they had to bail out if control was lost.
The engines drove a shaft across the middle of the frame, which via chain drive ran a differential underneath
which had, on its output shaft, a pair of drive chains down to the tracks on either side
The tracks themselve look a lot like the modern tracks on a bulldozer or tank today, except that instead of the current system of sprung road wheels to support the middle of the track sections, they used a roller chain under a fixed plate
Those parts are going to be the most challenging to build - lots of interchangeable parts that need to be made. One thing going for me on this project is that there are several of these engines still running, and the Maine Forest And Logging Museum up in Bradley Maine restored theirs just a few years ago, and they have put up a TON of pictures, videos, and drawings on their website that is an absolute treasure trove of information, much more than is available for lots of old engines. They did a complete teardown and restoration of their engine, which is now in beautiful running order.
http://www.maineforestandloggingmuseum.org/lombards-in-bradley
If you go through thier site, you can see all the steps they took, with photo and video documentation along the way. A lot of the work involved students from the University of Maine, which also has lots of information. They have a lot of history of these engines, including vintage photos, and even the parts catalog from the manufacturer!
Given all that available information, I am going to make this as detailed a model as I can, though there will always be some details that need to be modified to make this a working model at a small scale. The tracks will all be made, and since the style of chain used in the drive is not available (at least that I can find) at this size, the drive and roller chains will also be made. I have found the same style of drive chain in model scales, but only in plastic, not in metal so far.
The model will be to 1" to 1' scale, which makes it approximately 30" long, 8" wide, and 10-1/2" tall. It will have a 3" diameter copper boiler, which will be a butane fired single-firetube style rather than the original coal/wood option, though I will model in the outer shell of the original style boiler's firebox, it will just have a gas burner inside it. It is a simaler scale (slightly larger) than my Shay locomotive, they should make a great pair. Unlike the Shay, since this one won't need tracks to run on (since it has its own), I can run this one out in the yard with the front runners replaced with wheels!
So, on to the build. I am going to be drawing up the parts as I go, starting from the ground up. The first part will be the track plates, of which I will need only 58 (plus a few spares). Here is a picture of what the real tracks look like,
and here is my drawing of the plate shape:
To make this many identical parts, it only makes sense to make jigs/fixtures wherever possible. For the model, the plates will be cut from 3/4" wide x 3/16" thick stainless steel. Each plate will need to be milled to proper length, then have the fingers along the sides milled in, the holes cross drilled, the ends of the fingers rounded, and finally the traction ridge in the center shaped. To do all that I have come up with a holding fixture that will let me position the parts for an operation, and put in one after another to do that one operation. It has two areas relief cut in, one to hold the part lengthwise and the other to hold it sideways. Here is the base plate of the fixture:
and then the top plate that bolts down onto it:
It has a couple of sets of holes to position it for the different operations. And here it is in action milling the first test blank to length:
Next up will be to spend some time at the big vise with the power saw and cut a boxful of the plate blanks out so I can start shaping them. Pictures to follow during that process...
Kim:
Wow, Chris! I'm going to be following you on this one for sure! :popcorn:
If you choose to put out a set of drawings, or even a book based on your build, I'll buy it from you!
You don't think small, do you Chris? This is going to be fascinating!
Kim
Dan Rowe:
This will be fun to watch.
Stock Drive Products has the smallest roller chain I know of. The price is a bit steep but making chain will be tedious.
https://shop.sdp-si.com/catalog/?cid=p303
Dan
crueby:
--- Quote from: Kim on October 22, 2016, 08:48:57 PM ---Wow, Chris! I'm going to be following you on this one for sure! :popcorn:
If you choose to put out a set of drawings, or even a book based on your build, I'll buy it from you!
You don't think small, do you Chris? This is going to be fascinating!
Kim
--- End quote ---
I will be putting up the drawings as I go in the build, maybe it will get pulled into a book someday (love to hire Kozo to draft it all!).
And no, I don't think small - have built a number of engines-only, and got to the point where I want to see them go around by themselves. Now I understand the thinking of the folks who build the traction engines and power wagons.
crueby:
--- Quote from: Dan Rowe on October 22, 2016, 08:58:04 PM ---This will be fun to watch.
Stock Drive Products has the smallest roller chain I know of. The price is a bit steep but making chain will be tedious.
https://shop.sdp-si.com/catalog/?cid=p303
Dan
--- End quote ---
I had looked at their chain, but the big difference on the roller chain on the inside of the tracks is that the center pins actually have rollers on them that protrude outside the side links, so that they act like a linear roller bearing race for the tracks.
I have not seen any small (or large) chain like that produced now.
The drive chain
is a different style that is still used, but have not seen it in model sizes outside the plastic chain that MicroMark sells, and I just cant see putting a plastic drive chain on a model this heavy, plus next to the boiler with all the heat and oil and hot water (which acetal plastic does not like). Actually, I did find the drive chain style is now made by one of the gauge 1 loco makers (Regner or Roundhouse, forget which) out of brass for one of their models, but the price for the lengths I would need are way high, since they have to hand make it too.
Yup, it will be a tedious thing to make, but the look and function will be worth it. I hope!
Navigation
[0] Message Index
[#] Next page
Go to full version