Author Topic: Chris' Build of a Lombard Hauler Engine  (Read 428745 times)

Offline crueby

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Re: Chris' Build of a Lombard Hauler Engine
« Reply #435 on: December 18, 2016, 04:39:06 PM »
Dog that is cooler then a crawfish hitting a pot of hot water.......I........like........ :Love:


Don

I mainly read this thread to learn more of Don's pithy expressions.   ;D   :lolb:

Actually it's a great build even without them.  Still trying to figure out what role the roller chain plays.

I love them too! I would have used Lobster in the saying, but both work!

The roller chain acts like a linear set of needle bearings, along the bottom of the track frame so that the track plates are not rubbing along the frame but instead riding on the rollers. It is interesting that in his original patents, Lombard used a row of discs just like a more modern army tank would have the road wheels (though the modern version has overlapping rows), but for some reason after the initial prototype he switched to the roller chain method instead. I don't know why, seems more complicated and expensive than a set of discs - I know he had problems with breakage on the track plates early on, and switched to a different steel alloy for them, maybe that was part of the reason.

Here is the picture of the roller chain on the real one again:

Imagine as the track is driven around, and the weight of the whole machine (19 tons) is pressing down, the tracks push up into the roller chain, which presses against the flange above it (there is a roller chain on the inside of the track frame as well). The rollers move back at half the speed of the tracks, turning as they go, just like a ball bearing race would. Pretty clever solution to support the tracks against the ground.  Maybe the reason for the switch was to get more points of contact than it was feasible with rows of the discs, which only had 4 they way he did it. Here is a picture from the patent, you can see the discs in the lower left view:

With the discs, maybe there were problems with the track plates rocking more, with the chain version they would have been held more even.
Its also interesting that in the patent, the drive chain was on the outside, where in production he moved it to the inside. Neat stuff.


« Last Edit: May 31, 2018, 08:57:11 PM by crueby »

Offline kvom

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Re: Chris' Build of a Lombard Hauler Engine
« Reply #436 on: December 18, 2016, 06:45:44 PM »
OK, roller chain makes perfect sense.

Now how does it steer?  Can one track be disconnected from the other?

Offline crueby

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Re: Chris' Build of a Lombard Hauler Engine
« Reply #437 on: December 18, 2016, 04:52:48 PM »
OK, roller chain makes perfect sense.

Now how does it steer?  Can one track be disconnected from the other?

The steering was done just with the skis or wheels at the front, both tracks were always driven together. He did put a differential in the drive axle to allow the tracks the run at different speeds during a turn, but had not learned how to drive them independantly yet. According to the histories, he did experiment with having the differential earlier in the drive train, so the engines on either side could be run independantly, but found that when they got in sync with each other that the vibration made the machine want to hop up and down, so that was abandoned. The first prototype actually did not have the steerable ski, but used horses in front to pull it to the side, but that proved inefficient at best, and scared the road apples out of the horses when going downhill and the hauler sped up!
They ran the haulers on iced roadways, with ruts for the skis on the front and also the skis on the log sleds formed into the ice - they had machines (called 'rutters', imaginatively) they would pull along the roads to form the tracks and clear snow, and had crews pouring water at night to make the ice. The tracks on the hauler were on a wider stance, so they would not chew up the ruts.

Offline crueby

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Re: Chris' Build of a Lombard Hauler Engine
« Reply #438 on: December 18, 2016, 04:58:38 PM »
While waiting for the paint to dry on the axle assembly, I got blanks for the mounting bracket cut down out of a longer bar of 303 steel, milled the cut edges square, and laid out the first cuts. The box in the center shows where it will be made into a hollow box beam shape. As before, these lines are not milled to, but just are guides so I dont turn things around and mill the wrong side.

I started by milling the notch in one end where it fits around the main frame. The part still needs to be thinned a little, the bar was thicker than needed by a fraction.

Here is the first bracket sitting next to the painted axle (dry to touch, needs to sit and cure for a while still)

I'll get the other bracket notched, then continue with the shaping later...
« Last Edit: May 31, 2018, 08:57:25 PM by crueby »

Offline crueby

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Re: Chris' Build of a Lombard Hauler Engine
« Reply #439 on: December 19, 2016, 12:33:29 AM »
Continuing on with the axle support brackets, after milling the step in the end of both, I took a light cut off the back of the whole bracket to bring it down to the proper thickness (nearest size bar I had was one size up).

and then turned them on their side to chain drill the slot in the wide section, since the original part was a casting shaped like a box beam with a tab sticking up. I drilled halfway through from each side

and then used a mill to connect the holes up. This was done from either side, since the mill cutter is not long enough to reach all the way through (the part is a little over an inch wide).

and then came one of those 'nobody will ever be able to see this, but I'll know its there' moments - used a square needle file to square off the corners of the slot that the end mill left, to make it match the shape of the original part.

And then back to the mill, chain drilling around the perimeter of the opening where the axle box will slide in.

Followed by using the mill to take it out to size. You will note that I left the bottom in place - I will take that bit out last, after all the other shaping and drilling operations are done. Since the top tab will be shaped into a set of curves, if I cut the bottom opening out now then try and clamp it back in the vise, it would only have a narrow section at the top that goes full width.

Here are the parts to this stage sitting next to the axle blocks that they will slip over.

The next step will be to drill the mounting holes at the top, and shape the top into the curves like the original has. The paper to the side has the spacing for the holes worked out.

After that is done, I will go back and cut the bottom of the slot apart, and drill the holes in the base for the crossbar that closes the opening again, and angles up to the main frame.
« Last Edit: May 31, 2018, 08:57:30 PM by crueby »

Offline b.lindsey

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Re: Chris' Build of a Lombard Hauler Engine
« Reply #440 on: December 19, 2016, 01:17:25 AM »
Still following along quietly but in amazement Chris!!  Don't know what else to say.

Bill

Offline crueby

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Re: Chris' Build of a Lombard Hauler Engine
« Reply #441 on: December 19, 2016, 01:23:37 AM »
Still following along quietly but in amazement Chris!!  Don't know what else to say.

Bill

Thanks Bill!

How about 'pass the popcorn'?  :embarassed:

Offline Flyboy Jim

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Re: Chris' Build of a Lombard Hauler Engine
« Reply #442 on: December 19, 2016, 03:48:35 AM »
Dang...........that's a rather "busy" part!

It's been really interesting to see how you've taken the original drawings and figured out how to use bar stock to make the parts.

Jim
Sherline 4400 Lathe
Sherline 5400 Mill
"You can do small things on big machines, but you can do small things on small machines".

Offline crueby

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Re: Chris' Build of a Lombard Hauler Engine
« Reply #443 on: December 19, 2016, 04:32:01 AM »
Dang...........that's a rather "busy" part!

It's been really interesting to see how you've taken the original drawings and figured out how to use bar stock to make the parts.

Jim
Its got to be the most complicated bracket I've ever made!  If it was bigger I'd probably have made it from pieces, but at this size it was easier to carve it from solid. I'm sure the original was a cast part.

Offline Steamer5

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Re: Chris' Build of a Lombard Hauler Engine
« Reply #444 on: December 19, 2016, 11:35:26 AM »
Hi Chris,
 Its looking like a filing machine is needed in your Xmas Stocking!

Love what you are doing! Oh found a substitute for  :popcorn:.... Xmas mince pies! (Followed by a gym sub  :lolb:)

Cheers Kerrin
Get excited and make something!

Offline crueby

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Re: Chris' Build of a Lombard Hauler Engine
« Reply #445 on: December 19, 2016, 01:13:37 PM »
Hi Chris,
 Its looking like a filing machine is needed in your Xmas Stocking!

Love what you are doing! Oh found a substitute for  :popcorn:.... Xmas mince pies! (Followed by a gym sub  :lolb:)

Cheers Kerrin
A while back I bookmarked some filing machine builds, someday will make one... Not sure where I'd put it, shop is pretty full already!

Offline crueby

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Re: Chris' Build of a Lombard Hauler Engine
« Reply #446 on: December 19, 2016, 08:25:33 PM »
Continuing work on the axle brackets, next step was to decide how to fasten them to the main frame rails. Some of the parts on the original were bolted, some were rivetted - it was tough to tell how these brackets went on, so I decided to rivet them. The only pre-made small rivets that I have handy are all in brass, and besides wanting them to be steel, the brass ones were too short, so it was easy to decide to make them from bar stock. I can hear some of you out there right now, thinking I am nuts (pun!) to be making them, but it only took about 20 minutes to make 16 of them - not a big deal. They started out by turning the shank onto a length of bar stock:

and then parting them off:

These steps actually went quick because of two very handy features: a quick change tool post and zero-resettable handwheels, so once the first one was laid out, it was very quick to turn the same diameter over and over, counting turns from the end to get the length right.
After the parts were all done to that stage, each was chucked up once more by the shank, and a quick spin to smooth off the little nub that the parting tool left, as well as rounding over the head:

leaving this little pile of rivets:

With that done, I could then know what size holes to drill in the bracket tops:

and then drilled/tapped the holes in the base for the angled crossbar to be made later:

At this point, it was time to shape the top of the bracket into the curves that the original has. I started out by doing the concave sections with the mill, doing the same cut on each part and each side before moving on so that the two brackets would be symetric and match each other:

and the over to the disc/belt sander to do the outer curves (done on the left one in the photo):

leaving the parts at this stage:

Last step was to cut out the remaining part of the base, to free up the two sides and leave the slot. That was done with the hacksaw, then a few light passes on the mill to get it flush to the sides:

And the brackets are done! One needed a couple strokes of the file to get it to slide easily on the axle.

and here is where it will spend more of its time, once the spring frame is in place, with the rivets in the holes to show how they will look:

And the obligatory family shots:



Next stage I think will be making the angle brace that goes across the bottom of the brackets, and angle up to the bottom of the main frame...
« Last Edit: May 31, 2018, 08:57:46 PM by crueby »

Offline kvom

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Re: Chris' Build of a Lombard Hauler Engine
« Reply #447 on: December 19, 2016, 11:19:21 PM »
I would have suggested drive screws as an alternative to rivets, with solder as the primary attachment.

Offline crueby

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Re: Chris' Build of a Lombard Hauler Engine
« Reply #448 on: December 19, 2016, 09:24:37 PM »
I would have suggested drive screws as an alternative to rivets, with solder as the primary attachment.
This is setting the stage for the rest of the boiler/etc brackets, which are rivets in a lot of places on the original. The boiler and water tank will have many many of them.

Offline crueby

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Re: Chris' Build of a Lombard Hauler Engine
« Reply #449 on: December 20, 2016, 01:23:34 AM »
The angle braces for the bottom of the axle bracket are done, pretty straightforward pieces to make, they are a simple flat bar (plus a short reinforcing bar at the center), bent to shape and drilled for mount holes in the center and the ends.

Here is what they look like bolted into place - the main frame will run across the center bracket, and the ends of the angled bar bolt into the bottom of the frame rail.

Again with some paint added

and some shots with them bolted onto the axles...

With the black parts, its getting tough to arrange the lighting for decent pictures.



« Last Edit: May 31, 2018, 08:58:01 PM by crueby »

 

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