Large Scale Central

Remote mounting of a Bachmann switch stand

Track and Trestles
#1

I’ve been designing an adapter for the Bachmann 94648 switch stand, so that (for certain less accessible turnouts) the stand can be installed closer to the layout perimeter. This is the first article:

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A little video:

The problem is that the stand, set at 9mm throw, is just enough to operate my TrainLi throw bars. Since there is a tiny amount of clearance between the control cable and the ID of the tube, there is a miniscule bit of lateral play… which translates into slop in the throw distance.

I’ve bought numerous lengths of different tubes and cables from McMaster, and this is by far the best combination for close fit and freedom in sliding.

I wish the stands had adjustable throw! But, they don’t. Anyway, this 3’ long cable just barely works, but longer lengths will produce more slop and inadequate throw. Dang…

Maybe there’s other switch stands I should look at… like the ground throw from Llagas Creek. Can’t tell if they’re adjustable or sprung…?

Heck, maybe I should try brass barrel bolts. Anyone know of a design using those with a spring?

#2

Nice! The switch stands actually do have a bit of adjustable throw. Take one apart and peek inside.

#3

When doing something similar, I used RC Airplane push rod and bell cranks. The bell cranks and screw adjustments on the clevis allowed me to get the spacing right for a nice tight closure. It took some fiddling to make it work, but no problems since…

Fr. Fred swears by old school automotive choke cables.

2 Likes
#4

Thanks! True, they do have “Short” vs. “Long” on the internal arm, but I need just a leetle bit more than the “Long” (9mm).

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#5

That’s great Jon, thanks for those pics. You bet, a bell crank would certainly give the needed extra throw, good thinking.

#6

Years back doing that I just used choke/throttle cables.

#7

I do not think brass barrel bolts will give you the throw you want. i just looked at my one installation (no spring) and it has just enough throw IMHO. the Llagas Creek which i use are not sprung either. i think most folks that use chock cables just put a knob on the Fasia. I am Sure Joh Radder will jump in and show wheat he used for a couple of turnouts that i think he has done something similar but no springs.

Al P.

#8

some how i missed that Jon had already shown.

#9

Cliff did you do what Bob suggested?

#10

Yep; I was at the max throw position.

#11

Yes, that’s pretty much what I’m doing, except smaller. I’ve looked at cables on ebay, and they’re cheap enough, but fixed in length, and I want different end connections.

#12

After spending a most of a day of design investigation on reworking this, I’m heading towards abandoning the BM stand and heading back to my servo-controlled machine.

For ops purposes, I thought going Bachmann would expedite my switch control issues, but now it’s seeming more difficult than Plan A (servo).

Thanks all for being my group therapist in this matter, much appreciated. :grinning_face_with_smiling_eyes:

#13

I’m not a conspiracy theorist, but Cliff, has shared stories that you witnessed that he has a nemesis on another thread. Like me, are you MARVELLING that he has at least :two: Nemeses?

I came across these photos when I was searching for ”thing more powerful than a speeding locomotive” this morning.

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  • THE TRESTLE

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  • THE SWITCH

Could this mild mannered modeller have a a secret identity?

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Apparently we have a witness.:grinning:

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On the other hand, I wonder if It could be Vic after watching what he came up with during the Mik. I think you’d have to agree that build was “faster than a speeding bullet”. :grinning:

Does he have a nemesis? I better google that… and get back to you.

#14

Geeze Bill, you’re too much! :laughing: :laughing: :laughing:

And yeah I do look just like that, haha! :nerd_face:

#15

There is another Plan for potential operations sessions… Plan A minus 1 (Z?), which involves installing or replacing manual operators (Train Li, Bachmann) throughout, and also putting handy boxes of Band-Aids and sewing kits around the layout. Much cheaper, this Plan! :grinning_face_with_smiling_eyes: :grinning_face_with_smiling_eyes: :grinning_face_with_smiling_eyes:

#16

I have moved many a switch machine for may scales, including large scale. In most cases I used model airplane servo control rods, the type that slide inside of a plastic tube. These control RC rods are flexible and easy cut to the desired lengths. This probably wouldn’t work too well on an outside layout, but an inside permanent layout it’s a great way to hide your switch machines.

#17

I agree, Al. I could only find brass-plated steel, which neither lasts well, nor is solderable to (which I was counting on). And when retracted, the barrels (for all the ones I saw) come flush with the casing, preventing anything attached around the end of it.

#18

Thanks John. Yes, this was the first thing I tried. But due to slop in the tube, I chose the cable & tube combination I showed in the OP. My issue isn’t with this DIY mini choke cable, but in the throw of the BM switch stand, which is inadequate when any cable slop is introduced.

#19

Cliff,
I think your giving up too quickly which is something I have been told over the years on this forum! However I didn’t quit ( most of the time) I just went to bed sobbing and feeling violated!

With that said perhaps you should thing outside of the box a bit. Remember the switch stand has enough throw to work the switch properly with just the angled rod? I see that extra slop with cable set up you are using and it appears the barrel bolt pushes upward on the throw. I think a lot of the issue is the angle of the rod coming out of the switchstand and the way it’s set up inside " You are losing throw with the slop within the stand ". It’s Bachmann my friend it’s not precise but it works right??

So to me if I was gonna tackle the problem (remember you are re inventing) something that has already been designed and invented and this is something that a computer drawing cannot do. This is why in my field of profession there a LOTS of things called TSB’s.

Plan 69…Open up the switch stand and remove the rod insert an RC cable as suggested with an adjustable clevis.
Plan 69A …Keep the set up you have and abandon the Bachmann sloppy arm throw out of the stand and work off the 1/16" x 1/16" square where the target gets inserted (YES I said insert and reported myself to the moderator). Like an RC servo arm on top but make your cable have a straight shot at it and get rid of the barrel bolt connection. Next time I’ll write a memo on the fridge white board.

That make sense?
:rooster:

#20

I didn’t at first grasp what you were trying to do, which is not unusual. Looks way to complicated for me, when I used them, choke cables, I hooked the open end directly to the switch throw bar and mounted the handle end in a Shanty with a removable roof or on the table face.