And don’t forget pics on your choice and build 
Jon you still planning on going to Steamtown Sunday? Im heading over. I want to get their for 10 when doors open. They are open till 4PM
I’d really like to go. Got the word today we are being cut back 25% at work. With a kid in college our budget was already stretched without that cut. I’m going to play it by ear at this point.
Jon Radder said:If you decide let me know.
I'd really like to go. Got the word today we are being cut back 25% at work. With a kid in college our budget was already stretched without that cut. I'm going to play it by ear at this point.
OK - PM me your phone number - I’ll reply with my cell.
Shawn and Jon sittin in a tree…
Sorry…
I took a break from fantasizing about going to Steamtown with Shawn and looked into the car build some more. I’d like to build the super low-slung and short version like the ones at Cradle of Forestry. Thinking the beam is about 24 inches measured to the outside, I cut a piece of 13mm PVC board to length and width; located where the bolsters should be then tapped holes for 6-32 screws (thanks to Bruce for that trick). I then attached my Aristo Classic trucks (less couplers) to this test jig and took it down to the indoor division. It makes it through Aristo “wide” switches but the wheels bind on the beam in some of my mainline curves. And there is no way it will even attempt to go through R1 switches.
This leaves me at a decision point between two paths… A] Add a bolster to raise the beams above the wheels allowing unlimited swing -OR- B] make the center beams less then 24" across.
Choice A would loose the low-slung look that I really like. On the other hand I really can’t duplicate the prototypical look exactly because of how the model trucks are made. On the plus side, choice A would allow the cars to be stored in my R1 yards.
Choice B seems to be where I’m leaning if I can get the clearance I need without going too narrow. I planned the beams to be 6" high by 8" across. I could change them to 6x6 reducing the width to 18" -OR- I could keep the 6x8 and reduce the space between to less than a beam width. I think that might look a little odd.
Opinions?
Mill reliefs behind the wheels. When they are loaded you won’t see it - or- yes, go a little narrower, your eye really won’t notice the beams are undersized if they are all the same.
Jon I would go a little more narrow. Like Mik said you wont notice it much. If you raise it up it wont look as good being so high off the ground. or make a few of each size.
If you use 5/16" square for the sills and 1/4" x 5/16" for the center spacers, the beam will be 7/8" wide (or 21" in 1/24) See if that is enough to make them happy on your curves… Then you can always add a 1/16" thick pad if it doesn’t - bringing the tops in line with what you had before. Then if they look too high, maybe add airbrake cylinders and beams to fill up that space underneath… There’s more than one way to skin this cat.
Mik - Thanks. I’m building in 1:20 and I work in metric 'cause it’s easy (1 foot - 15mm). I’ll keep experimenting. I need to clean off the table saw so I can rip down my test piece to find the width that works and design backwards from there. I don’t need much more if I forget the R1 yards.
Jon:
Mik’s suggestion to mill reliefs in the center sill where the wheels would touch is actually prototypical. I don’t remember the RRs where that was done, but there are pictures clearly showing that as a solution. These ‘cuts’ were definitely added by the builders, and not just a result of contact with the wheels.
I’ll try to find some of these pictures in my library.
Happy RRing,
Jerry
Thanks Jerry. Yes, pictures would be great if you find any. They would answer my questions on how the relief would look. I imagine it to be angular cuts ahead of and behind the bolster to give the most clearance with the least amount of structure removed.
BTW, I realize know that I’ve mixed up the terminology between beams and sills. You guys know what I was talking about though - thanks!
Jon:
The reliefs I have seen in pix are circular, with just a little larger radius than the wheel that they provide clearance for. They are tapered, and at first glance look like they were carved by the wheel.
In fact, they were cut (probably with hand tools) just deep enough to provide clearance for the wheels.
I’ll look for pix tonight.
Happy RRing,
Jerry
I believe you can see similar reliefs on the AMS log cars as well.
Are they done yet?
No not done, but further tests were run with the test mock-up. It appears that the binding is not as bad as I first thought - I had the trucks a bit off center. I double checked the measurement of my mock-up and it’s a few mm wide. So I think I’ll probably be good for the main-line with the originally proposed 24" width across the sills without milling any relief. If I go just a bit thinner I might be able to get into the R1 yards.
Couplers are going to be very high compared to other cars, but that’s really not a problem as these will always be run by themselves.
I also looked at what I could do to the trucks to lower the sills even further. there is about a 1/8" that I could trim off the top of the truck. That would help a lot with the coupler height and the look.
In order to keep this project moving forward, I created a Build Log here: http://www.largescalecentral.com/LSCForums/viewtopic.php?pid=143300#p143300
Nice work Jon.