SP AC-9

[carlso]

Well to show that I have not given up, here are some images of my EM-1 to AC-9 project. By no stretch of the imagination does it belong on the wire when thinking about the many extremely talented scratchers and bashers but it is mine and considering my 74 year old eyes and fingers are quite a challenge, I am happy with the results. It is not complete and I have a lot of weathering and other work to do such as train numbers and green class lights. I do have the correct pilot truck to mount and I see that I need to touch up some paint on porch. At any rate it is coming along and I should have it complete in another 3-4 weeks. Now watch B'mann come out with the AC-9, wouldn't that figure.







Yes I know the headlight is not correct but the cast one was not usable and I had to scratch one but it does have led. Thanks for looking.

Carl

[victor miranda]

I like it.

I think the camera is doing funny things with the 3/4 view. 
It does not look straight.
The other photos look right.

is the eccentric crank on the lead engine correct?
it seems wide of center.

who cares if b-mann brings out an ac-9. yours is first!

victor

[carlso]

Victor,

thanks for the reply. The boiler shell and pilot are not attached permanently as yet so yes the pilot is leaning. It won't be. I am not smart enough to understand your comment about the eccentric crank being wide of center. Please, explain what you mean by that. My concern comes from the fact that I dropped the mechanism onto the garage floor while doing some grinding. I had to re-attach an item but that was on the second engine. I may have a problem and don't know it.

I can't claim the first as this is one of Jason's castings but I will be very happy with having a non brass version completed by an idiot.

Carl

[victor miranda]

hi carlso,

how to explain eccentric cranks...

I edited a photo.  the eccentric crank is leaning towards the front of the loco. Front is left.
It has a brass rivet in it.
The more it leans toward the front, the wider of center it is.



victor

[carlso]

Victor,

thanks for taking up your time with the picture and explanation. I see how the eccentric is leaning towards the front in your example. But wouldn't that lean be determined by where the rods came to rest? Or, is that determined by placing the weight on topside, as in your photo, and the bottom of the crank dead center on bottom.

Pardon my ignorance as I am trying to understand the workings of the steamer. I have been a steam fan for 74 years now but never this involved with one. Will it effect the running characteristics?

Carl

[peteski]

Carl,
in N scale electric steamers the valve gear is strictly a cosmetic item. Unless it is grossly misaligned, the model will run, even with the valve gear not set up quite correctly. But since these are scale models, most people try to make them look realistic.

For more info about (the real) valve gear see http://en.wikipedia.org/wiki/Valve_gear
On that page there is a link to other pages describing the specific versions of valve gears. This one (most commonly used valve gear) has a nice animation showing how it works and how all the parts interact. http://en.wikipedia.org/wiki/Walschaerts_valve_gear

EDIT: here is the animation:


Best way to be accurately model something is to learn how the 1:1 scale object works. 

[carlso]

peteski- thanks for the leads, I appreciate them. The front engine is just as delivered by B'mann. I am not suggesting that they had it either wright or wrong. It ran extremely well before my project and I hope beyond hope that it will again.

Carl