12" working railroad

[rkcarguy]

Getting things jigged up ready for welding.

[rkcarguy]

The frame is now mostly welded up...I've got to hit a few more spots and then there is a couple inside corner seams I want to solder to seal up without having a big weld bead to deal with. Everything fit really well. I used a set of calipers to make sure my bolster pin holes were centered on the frame and got them within .005".
Using the TIG is taking longer, but I'm able to jump around and lay down much nicer welds while keeping heat down so the welds don't warp anything.

[rkcarguy]

I loaded up the frame in the truck today with the forklift and took it home. I'm surprised how stiff it is. I carefully walked across it....no give....hopped up and down a little, still no give....jumped up and down....still very minimal flex. And no it didn't bend haha even though I'm 270#'s. I'm still going to build an upper sub frame to mount the fuel and hydraulic oil tanks to, but I don't think its needed for structural support. The L3-1/2 x 2-1/2 x 1/4 is very strong, even with the short leg vertical.
I got the calipers out and measured my frame rail to cross-member difference, and then the bolster to truck side clearance and wrote down the #'s so I can draw them into my CAD drawing and figure out my "slide bearing" bracket height for proper ride/coupler height.
So next up, slide bearing brackets, fuel tank(muffler), the air tanks on each side, and then its time to mount the engine and body.

[rkcarguy]

Here's the test fit of the bolster bearing brackets. These bearings are rated at 280#'s each and this thing could end up weighing 1000#'s plus I have no idea, so I doubled them up. Everything looks good so I will shot blast and paint them, and remount them for good this weekend. Maybe my setup is making sense now? The center pillow block I've loosened up the self-aligning portion by grinding out the casting with a flap wheel, and then the bearings actually take the load and allow the truck to pivot forward and back but not side to side(would tip the locomotive). This way the truck can align itself to the track and distribute weight evenly to each wheel independent of the springs.

[0351]

Rkcarguy,
I see that the response to rate our post have slacked off lately. Guess real world life has got everyone busy. Please keep on posting updates. Always look forward to them . II'm interested in hearing how well this type of bolster bearing design works out. Looks like when loco's weight is centered and level the bearing is will taking the full brunt weight of the loco.
How much of a gap will be between outer side bolster bearings and the boslster plate? 1/4"?
What are you using to hold the springs in seated place on the spring perches? In the photo it looks as if there is a bolt thru the perch? "

[0351]

On a different subject, back to your posts on building a turnout. I came across some photos of another 3/8"x1" flat bar turnout build that look great. I like the design of using 1/4"x2" tie bars to keep everything in place. Seems like a lot less to go wrong.

[Harold_V]

Pretty welds!
H

[rkcarguy]

The height difference between the top of the bolster and the bottom of the frame to attain the right coupler height ended up being 1.808". The center pillow block is merely there to pivot and swivel with the bolster pin to keep the truck in place, the four bearings on each side of it in the brackets take the load and allow the trucks to articulate to any up-down track condition parallel to the rails while not allowing the locomotive to lean. On my bulkhead flat cars I'm going use solid bronze bushings instead of the ball bearings so they can withstand a lot more weight.
I am planning on signaling my whole RR so I needed the rails to be isolated so that's why I went with groovy track on wood ties. Not only that but my full track layout plan involves about 1600 ties, and I've been able to round up wood from crates, forms, pallets, construction scraps, etc for free to make ties from while I'm probably looking at over $1000 in flat bar rail as it is, even wholesale.
Hearing from long term "groovy track" users, they say the rail actually rusts into the grooves and becomes very secure in there. However I had a whole bunch of tie plates laser cut from 1/8" steel that I will weld to the rails and screw to the ties at an interval just for good measure.
Speaking of ties, I was able to gather a bunch of old deck stain (mostly redwood color), some water proofer (main ingredient is linseed oil) from relatives and blend it with some more boiled linseed oil and black oil based marine enamel, and came up with a nice dark brown that penetrates really well and I have about 8 gallons of it. I soaked a piece of test wood in it and it's been outside for a month and shows no sign of moisture intrusion. I just need to find or make some kind of metal container with a lid so I can soak the full length ties and I'll start staining the ones that are done.

As far as the truck springs, yes I used some short button head bolts with washers that closely fit the inside of the spring. The reason for this is if I need to change my springs to something of a different diameter I can remove the bolts and change the "perch" to suit with different washers/spacers. If I was confident that the springs were adequate I would just plug weld some washers in place and not use any bolts. They are the large diameter Volvo red block valve springs which are supposed to be 110# springs, but I don't know what their compression rates are or anything else so I just have to try them when it's all done. Many of these valve springs start out in that range but are in the 280-350# range at full rated compression if you look at specs on Summit Racing. In fact, Summit had some valve springs that were in the $35 range for 16 that I think would work pretty well for your freight trucks.

[tomc]

We used chevy high performance valve springs on our trucks.

I believe spring rate is how many pounds compress the spring one inch.

Tom C.

[rkcarguy]

We used chevy high performance valve springs on our trucks.

I believe spring rate is how many pounds compress the spring one inch.

Tom C.

These are what I sized your freight trucks for Curtiss.
https://www.summitracing.com/parts/hrs-98214/overview/
$33 will get you 16 springs, so good for 2 cars worth of rolling stock.

When I compress mine in the Vise, they do stiffen up the more I tighten, so I should be ok. Lucky us we can use (or re-use) valve springs for our larger scale trains.

[NP317]

For soaking your ties, find an old large stainless steel kitchen sink, post-kitchen remodel.
Plug the drain and pop a plywood lid on top.
Simple.
~RN

[rkcarguy]

I'd like something that I don't have to drain and refill, and need metal/sealable because the BLO can spontaneously combust!
I may look into a chunk of pipe that I can put 4-5 at a time into, with a cap welded on the bottom and some kind of sealing lid on top.