Suspension problems

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jscarmozza
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Joined: Mon Mar 03, 2014 5:09 pm

Suspension problems

Post by jscarmozza » Mon May 13, 2019 7:16 am

I need advice on how to properly balance the wheel loads on my 1" LE Atlantic, the drivers are slipping badly. Is the purpose of the equalized suspension just to maintain wheel contact with the rails, or is it also a means to adjust the weight distribution on the wheels? If it is a means to adjust the weight distribution, how is that done, if not, how do you get more weight on the drivers?

I have the engine on a work stand, and with everything in its place on a level track, I noticed the journals are bottomed out and the drivers are barely touching the track. When I remove the trailing truck heart rockers, the drivers take much more of the engines weight and the driver journals lift up off the bottom about 1/16". I checked the heart rocker dimensions and they match the plan dimensions. The trailing truck walking beam pins are in the center of the three hole adjustment array, is there a way of adjusting the trailing truck to transfer more load to the drivers and how would that be done?

It also appears, from looking at the plans, that one of the two seat pins on the trailing truck heart rockers should lift off the seat when the engine enters a curve and return when it leaves the curve, the rockers fit so tightly they won't rock. I don't think this is causing the suspension problem, but if they are supposed to rock, then I want them too. Advice will be appreciated.
John

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makinsmoke
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Re: Suspension problems

Post by makinsmoke » Mon May 13, 2019 12:50 pm

Do you have water in the boiler or compensated for lack of?

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FLtenwheeler
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Re: Suspension problems

Post by FLtenwheeler » Mon May 13, 2019 1:46 pm

Bruce Raykiewicz had to adjust the lead and trailing truck loads on his Little Engines 1.5 scale Atlantic to get it to pull.

Tim
He who dies with the most unfinished projects: Should of put more time into their hobby.

Pontiacguy1
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Location: Tennessee, USA

Re: Suspension problems

Post by Pontiacguy1 » Mon May 13, 2019 4:36 pm

every LE atlantic that I've ever seen had to have the suspension adjusted or modified so that it would pull anything more than itself and the engineer around. From what I've seen with them, if you build it by the plans, then the lead and trailing trucks have about 50% or more of the locomotive weight, and she'll be really slippery. One guy I know decided to see why it wouldn't pull... Took both the lead and trailing trucks off and ran it around the track a time or two as an 0-4-0, and it pulled incredibly well. He then went back and worked on his suspension until he got about 75% of the weight on the drivers, and was much happier with it. Have seen the same thing on other LE atlantics as well.

jscarmozza
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Joined: Mon Mar 03, 2014 5:09 pm

Re: Suspension problems

Post by jscarmozza » Mon May 13, 2019 5:00 pm

Do you have any idea how he did it? I've been working on it all day today...very difficult, and I really don't know what I'm doing.

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Fender
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Re: Suspension problems

Post by Fender » Mon May 13, 2019 7:33 pm

There should be a lever connecting the rear driver equalizer to the trailing truck, as well as another lever from the lead driver to the lead truck. You want to modify these, so that the fulcrum (the pivot point on these levers) is closer to the drivers than it is to the truck. This will cause more of the loco weight to be borne on the drivers.
Dan Watson

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Fender
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Re: Suspension problems

Post by Fender » Mon May 13, 2019 8:17 pm

To be clear, here is what I am saying. The "Equal" diagram is representative of what you have now. The "Unequal" is what you need for more weight on drivers.
Attachments
Equal.jpg
Unequal.jpg
Dan Watson

Berkman
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Re: Suspension problems

Post by Berkman » Mon May 13, 2019 8:21 pm

Might also have to adjust the thickness of the front bolster where the lead truck mounts, possibly remove shims or slightly machine it to let the lead truck carry less weight. And/Or remove leafs from the front truck suspension to make it less firm.

Also, possibly adjust the elevation of the swivels on the delta truck to have them be higher up, which will also remove weight from the delta truck.

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NP317
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Re: Suspension problems

Post by NP317 » Mon May 13, 2019 10:30 pm

For comparison, my Ten Wheeler has less than 9% of the total engine weight on the two axle lead truck. Just enough so it will not derail.
All the remaining weight is on the drivers.
Adjustment (thinning) of the lead truck bolster bearing was the primary solution.
~RN

Glenn Brooks
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Re: Suspension problems

Post by Glenn Brooks » Tue May 14, 2019 12:50 am

Should the heart rockers on the trucks also be worked on to be a more easy motion - not super stiff as the PO described??

GPB
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Motive power : 1902 A.S.Campbell 4-4-0 American - 12 5/8" gauge, 1955 Ottaway 4-4-0 American 12" gauge

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pat1027
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Re: Suspension problems

Post by pat1027 » Tue May 14, 2019 6:51 am

Dave did a nice video checking weight on a locomotives axles.


michaellynn2
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Re: Suspension problems

Post by michaellynn2 » Tue May 14, 2019 7:37 am

All these pointers on suspension are great except, the front truck is not equalized onto the Atlantic drivers. It is a 4-4-2. The front truck is independent. All the equalization travels from the drivers to the trailing truck. My LE Pacific has the same problems as the LE Atlantic. The equalization between the drivers and the trailing truck does have a fulcrum pin and I put my pin in the front position to add weight to the drivers. Dan Watson make a good diagram to show how it works.
I also added length to my spring hangers to make the drivers sit lower in the pedestals. This action caused the frame to elevate and lift more weight off the front truck.
michael george

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