The Home Machinist!

jcbrock wrote:WIG (Wolfram Inert Gas) is the equivalent to TIG (Tungsten Inert Gas) here in the US.

Wolfram is the technical name assigned to tungsten, so that makes sense. I had failed to make the connection until I read your post.

Beautiful workmanship, Chris. Keep sharing your progress.

I agree fully. I have long been impressed by those who build faithful to prototype models, which these guys seem to have as an objective.

Harold

Hi Guys,

just want to share some pics of my new Rods.
Milled by CNC , for the test i've made it out of Aluminium.
Everthing looks good , so i will produce the rods out of
stainless Steel. The runing gear will run with roller bearings all out.
But those i have to buy, when i get it i will report further.





All the Best
Chris

Ahhh. The joys of CNC machining!
~RN

Chris,
Like those tandem side rods (which were common with all Timken Northerns)!
Asteamhead

The first NYC 4-8-4 Niagara #6000 started out with 1 side rod. As testing began on that engine it bent the side rod and then the NYC added the tandem rod. These engines had over 6000 horsepower! I have a picture in my collection where a Niagara had a stuck cylinder cock and bent the main rod off the driver without derailing the engine.

Hey Giant,
I think you're talking about that pic...

All the Best
Chtis

Giant, Chris,
when I saw this picture for the first time, I wondered if not the reason for that failure was due to a miscalculated construction of the multible cross head solution by Timken cy. Look, crosshead and upper shoe are connected by just 4 bolts. These are stressed by changing forces at the end of the stroke at each revolution. If any of them gets loose, destruction will start!
N&W decided to use the identical Timken crosshead as alligator design in favour of avoiding such problems and less maintainance cost (and improved safety?).
Just my 2 cents based on an engineering background. Any replys are welcome!

Asteamhead

Interesting that the piston rod appears to be hollow?

makinsmoke wrote:Interesting that the piston rod appears to be hollow?

From the information I researched the main rods and side rods were made from a light weight steel. I came across the chemical composition and called a steel company and gave them the information and the closest material today was titanium. That could be the reason why they are hollow, to save on the cost. Maybe Harold could add some wisdom as well.

little giant,
building the A 1239 with Timken running gear of the N&W, I gathered every sort of information including the drawings of such equipment. The NYC Niagaras, Santa Fe' s 3776 and 2900 as N&W 600 and C&O 614 all used the Timken lightweight running gear with tandem rods. Slight differences were made regarding multible or alligator crossheads, guides and shoes.
Shoes first made of aluminium(!) as were pistons to reduce reciprocating weight to a minimum had been replaced by more rugged ones made of bronze later on.
The lightweight piston rods had been bored hollow for the same reason - reduced weight to increase maximum rev / min. Dimensions were 5 or 5 1/2 " diameter, bore was 3 1/4 to 3 1/2 ".
Most parts were made of Timken high dynamic steel (carbon 40-43, manganese 70-80, nickel 170-180, chromium 70-80, molybdenium 28-33.
Data is of drawing no. E-42849 of the N&WHS.
The crosshead centers wwere clamped by 2 x 4 1" precision bolts, which connected the shoes as well.
Both (single side) multible or (double) alligator crossheads could be used. The single sided crossheads got a weight to balance the tilting forces.
The only weak point with single sided crossheads were those just 4 bolts to connect centers to the crosshead body (my opinion).

Please let me show my model version of that state of the art prototype made by Timken.
No doubt hat Timken running gear was the last word for modern steam locomotives!

Asteamhead

makinsmoke wrote:Interesting that the piston rod appears to be hollow?

If memory serves, the piston rod on the Big Boy was (also) hollow. I'll see if I can locate the article published in the early 60's, which clearly showed a cut rod. Several of the Big Boys were scrapped by Geneva Steel (now defunct), a steel mill in Utah County.

Harold

Harold_V wrote:

makinsmoke wrote:Interesting that the piston rod appears to be hollow?

If memory serves, the piston rod on the Big Boy was (also) hollow. I'll see if I can locate the article published in the early 60's, which clearly showed a cut rod. Several of the Big Boys were scrapped by Geneva Steel (now defunct), a steel mill in Utah County.

Harold

Here's the Big Boy that's on display in Texas. You can see the hollow piston rod. Too bad they cut it.