# Truck springs



## Burl (Jan 2, 2008)

I had been using Aristo’s modern roller bearing trucks for almost all my scratch-built rolling stock. Now that they’ve become scarce, it’s pushed me to find an alternative. Below is what I’ve come up with. This is just a rendering of a Sketchup drawing – I’m having the first set printed in SLS nylon & don’t have them yet. I intend to put Gary Raymond 33” wheels in them, with flanged ball bearings in the journals.



After my experiment with the AAR-type B trucks, I have realized I need much weaker springs. Spring steel is way too stiff. I’m looking at phosphor bronze now. I realize I could wind my own, but I’m afraid they wouldn’t be consistent. This particular truck has two different size springs. In 1:29, they work out to 0.1896” & 0.1034” OD. Fully compressed, they need to be 0.1916”. I will probably experiment with whatever I can get from McMaster-Carr, but I was wondering if anyone had any resources for miniature springs they’d be willing to share?


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## bnsfconductor (Jan 3, 2008)

Call Precision Scale Models Engineering. http://www.psmescale.com/
They have a wide variety of springs, and they might have what you are looking for. I think that they also have a tool that makes making springs easier. 
Craig


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## SD90WLMT (Feb 16, 2010)

Hi Burl...

Impressive renderings you have come up with....
I have to ask .."where" ... you come up with the info and dimensions to create these fine drawings? 

Dirk


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## Trains (Jan 2, 2008)

Burl,

How about K/D coupler springs?

Don


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## Burl (Jan 2, 2008)

Dirk: I worked from drawings in the 1961 Car Builders' Cyclopedia.


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## SD90WLMT (Feb 16, 2010)

Is this rendering drawn completely in Sketchup...?
Thanks Burl..

D


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## Burl (Jan 2, 2008)

The drawing was made in Sketchup. I used a 3rd party plugin to render it.


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## pinewoods (Jan 20, 2009)

Did you think about have the springs printed in the nylon? It may be pushing the boundaries a bit but they should be soft enough.


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## Burl (Jan 2, 2008)

No, I had not thought of that. Nylon at that diameter doesn't have much spring to it, but maybe I could use one stiff spring in the back.


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## SD90WLMT (Feb 16, 2010)

Will A/C or USAT oem springs fill the bill...

Thinking out loud...

D


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## Burl (Jan 2, 2008)

If A/C means Aristo Craft, where would you get them? They are about the right OD for the big spring. Maybe a Kadee spring would work for the little one.


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## SD90WLMT (Feb 16, 2010)

Yes A/C means Aristo Craft

You may have this info...

A/C spring - 6 per truck
Height .. uncompressed - .3660"
Wire diam. - .021"

USA Trains metal truck - 6 per truck
Height .. uncompressed - .360"
Wire diam. - .0215"

Please don't ask how many times I dropped these tiny slippery springs trying to measure them..

Dirk


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## SD90WLMT (Feb 16, 2010)

and....incidentally....

..both springs have the same number of coils..or turns..

D


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## SD90WLMT (Feb 16, 2010)

The USA Trains truck used here for comparision is a metal framed typical of those used on both the 4-bay covered hopper ..or ..the new auto-rack cars...

Plastic truck frames are used on the intermodal car..but the spring is the " same " ....

I'd call Mike in parts and see what's cooking at USA....they keep many small items on hand.

D


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## Daniel Peck (Mar 31, 2009)

LEE SPRING has tons of springs.


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## SD90WLMT (Feb 16, 2010)

Got contact info Daniel..?

D


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## Ironton (Jan 2, 2008)

Why don't you print a spring in nylon or something flexible with no center. I mean you would see the scale spring but only the outer 1/2 of the coil would be printed. Then you could hide a real metal spring inside the printed one.


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## Daniel Peck (Mar 31, 2009)

SD90WLMT said:


> Got contact info Daniel..?
> 
> D


 http://www.leespring.com/?gclid=CMXerNSk0b4CFXRo7Aode2YAJg

Here yougo I replaace me ac springs with stainless ones.


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## Burl (Jan 2, 2008)

I received my first print from Shapeways today. It needs a couple things tweeked.

I made the bolster a little too narrow. You can’t really tell in the photo, but I had to add a block of styrene to the sideframes (right under the writing) to keep the bolster from twisting & clearing the printed stops.

The spring seats need to be a little wider to keep the springs centered.

My biggest problem is that the springs are too soft. There are 8 printed springs & 6 metal springs in each truck. I thought I could leave out the innermost printed springs if needs be, but even with all the springs in, its too soft. I will probably order some metal springs from the links some of you provided & keep experimenting. I tried a set from a spare set of Aristo Craft trucks I had lying around, but they were too stiff. Or I guess I could run with them bottomed out. At least I know they’d track that way.

Some of the sideframes have very visible print lines. That would seem to indicate Shapeways is manipulating the individual parts within my file to re-orient them. I am considering printing a master in acrylic to solve this problem. I’m happy with the bolsters in SLS nylon.


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## CliffyJ (Apr 29, 2009)

A thing of beauty, Burl.


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## Burl (Jan 2, 2008)

Daniel: do you happen to have a part # for your springs?


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## SD90WLMT (Feb 16, 2010)

Yea...this 3D printing is really amazing....

Love to see your next version...even with a coat of paint on...

What car weight are you placing on these that compress or don't compress the springs...

A 100 Ton hopper is rather light...
A box car certainly is heavier....

Dirk..thanks Burl


Our model world uses the same springs..regardless of car body


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## Burl (Jan 2, 2008)




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## SD90WLMT (Feb 16, 2010)

Burl, your even a mind reader!

Looks incredible too painted..

Dirk


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## Scott (Jan 29, 2008)

Totally Brilliant work mate. I haven't played with Shapeways for a while as it wasn't working for my door assembly - but your work gives me inspiration and the drive to continue on.


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## Burl (Jan 2, 2008)

Jonesy: what kind of problems were you having?


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## Scott (Jan 29, 2008)

It was coming out too fine for the printers (Modelling 1:1 and then downsizing to 1:24). After so much dicking around and trying to get it right. I gave it a break - as sometimes I'll think of a solution. So what I do now for most items is that I draw them to scale 1:24 and allow a bit more in thickness / tolerance in order to have the print work first time. So most items have a minimum thickness of 1 to 1.5mm. Anything under 1 inch (1:1) is compensated for and allows a bit more durability for handling.


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## Burl (Jan 2, 2008)

I have had much less frustration with Shapeways if I limit my minimum thickness to 1mm. I know they claim 0.8mm, but I was having a lot of misprints at that thickness.


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## Burl (Jan 2, 2008)

I got my Gary Raymond wheels in this week, as well as some suitable springs. I decided to go with Kadee (IH) 701 springs, cut in half, for the main springs - they're in the back row, so you can't see them. Kadee #875 springs were used for the smaller springs in the middle row. That gave enough support to let the whole assembly flex without bottoming out. For the main visible springs, I used my 3d printed springs - which have the diameter correctly scaled.

This is the first set of Gary Raymond wheels I have had, and I am very impressed. I wasn't expecting the wheel backs to be machined out, but man do they look nice. These would look great on a covered hopper, or a tank car.


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## ewarhol (Mar 3, 2014)

Wow, that's a nice looking truck!!!


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