A cheap hi-rail?

[daniel_leavitt2000]

After trying to rebuild several Samhongsa brass engines for a friend, I am left with a pile of parts. One of these parts is a truck (the other truck was used to rebuild a melted engine). I noticed the idler gears are very small. They are only about 4mm or less. These have a 1.5mm hole. I am thinking these could be used on a small chevy hi-rail truck. With the 9v pager motor, there will be no need for resisters. I am trying to find a good sorce for mini-wheels, the guide wheels used on hi-rails. While I want the truck's wheels to pick up power, it is essential for the guide wheels to collect current as well. Any ideas?

[SquirrelHollow]

Your best bet will probably be the wheels from Marklin Z tender trucks. 

You might also try http://www.republiclocomotiveworks.com/, Gold Rush Models (through dealers), or http://www.aspenmodel.com/ for Nn3/Z wheels/trucks.

The only other thing I can think of right now, would be Bachmann 4-4-0 tender wheels.  They would need narrowing, and flange milling to be acceptable visually.

None of what I listed would be appropriate for proper scale, though.

[DKS]

I actually think it would be easiest to make them from scratch. Perhaps start with very small brass washers (like a 00-90) and CA short lengths of styrene rod to them...

While on this topic, this may be of some interest: http://whiteriverandnorthern.net/clinic_35.htm

The GHQ kit includes the guide wheels, but the kit appears to have been discontinued.

[SquirrelHollow]

It's hard to tell from the photo, but these hubs *might* be usable.
http://www.republiclocomotiveworks.com/newRLW/show_item.php?ID=1109 (no picture)

http://www.republiclocomotiveworks.com/newRLW/show_item.php?ID=1 (picture with plastic hubs)

[daniel_leavitt2000]

Dave, your my hero. That looks possible for me. Now, if I use a 9V pager motor, I woulden't need the circutry in the brass channel. I could fill that with putty. I wonder if that will fix some of the performance issues yours had. BTW, where did you get a worm to fit the tiny pager motor shaft?

[DKS]

Dave, your my hero. That looks possible for me. Now, if I use a 9V pager motor, I woulden't need the circutry in the brass channel. I could fill that with putty. I wonder if that will fix some of the performance issues yours had. BTW, where did you get a worm to fit the tiny pager motor shaft?

I'm afraid the worm and gear both came from the "junk box," which means they could have come from anywhere! Sorry...

[sparky]

The gearing, especially a tiny worm gear, is the hold up to many projects I have in mind.  I have searched at great length to no avail.  I can't believe in this age of micro electronics and experimenters in many hobbies, that no one is manufacturing micro gears.

David- I remember from your article that your main disappointment in the hi-rail project was the lack of motor torque.  There are now 3V gearhead  pager motors available producing .28 oz/in of torque in a package less than 6 X 20mm!  That should be plenty to move that truck along.  A cap or toolboxes on the truck bed could hide the motor.

http://www.robotshop.ca/home/products/robot-parts/motors/gear-motors/planetary-gearmotors/solarbotics-gm15-gear-motor.html

Now to find a worm gear...

[Zox]

This is probably a stupid question, but--has anyone tried using a small threaded rod/bolt as a worm gear? It shouldn't be impossible to find or make something that would mate with a standard thread...

[DKS]

The gearing, especially a tiny worm gear, is the hold up to many projects I have in mind.  I have searched at great length to no avail.  I can't believe in this age of micro electronics and experimenters in many hobbies, that no one is manufacturing micro gears.

David- I remember from your article that your main disappointment in the hi-rail project was the lack of motor torque.  There are now 3V gearhead  pager motors available producing .28 oz/in of torque in a package less than 6 X 20mm!  That should be plenty to move that truck along.  A cap or toolboxes on the truck bed could hide the motor.

My source for tiny worms/worm gears has generally been non-functional Z scale locomotives (can sometimes fund duds on eBay for cheap), as well as small animated plastic toys--I can occasionally be found wandering around the toy section of Wally World looking for potential sources of spare parts.

Re: the motor, not lack of torque but lack of traction (I should re-word that part of the article; it is misleading). I think the non-powered wheels create too much drag, and the powered wheels do more slipping than driving. Also... I already have some of those gearhead pager motors; the are quite fantastic except... the driveshaft is a solid plastic belt pulley. Ugh. There are other sources of gearhead pager motors; I am away from my home computer, so I don't have all my links handy. I'll update this post later.

This is probably a stupid question, but--has anyone tried using a small threaded rod/bolt as a worm gear? It shouldn't be impossible to find or make something that would mate with a standard thread...

Yes, I have, and it generally doesn't work well. Worms have much deeper grooves than threaded rod, and they are shaped differently to properly engage the teeth of worm gears. Threaded rod may get a gear to turn, but it will be prone to slipping or binding.

[sparky]

There are other sources of gearhead pager motors; I am away from my home computer, so I don't have all my links handy. I'll update this post later.

Excellent.  I'm looking forward to it.

[DKS]

This place has a wide range of planetary gearmotors; I've ordered a few samples from them. Their planetary pager gearmotors have plastic shafts, but at least they aren't pulleys (considering the tiny loads placed on these motors, I can't see a problem with plastic other than being a bit fat to work with). I haven't gotten around to trying their gears, as they seem a bit pricey, but I may get there someday:

http://www.gizmoszone.com/

Then there's this potential source for micromotors and gear assemblies, which may be suited for projects like the hi-rail, including an incredible 4 x 8 mm pagermotor (about half the size of the typical pager motor, for 6 Euros apiece, I gather). In German only, I'm afraid:

http://www.mikroantriebe.de/

I've not explored the site thoroughly yet, so I don't know if we can order from the U.S., and unfortunately the Google Translator chokes on their online shop. It would appear they specialize in supplies for the Faller powered vehicle sets, as they have pre-assembled steering wheels and drive assemblies, amongst other assorted goodies such as micro-servos and memory wire.

EDIT: Thanks to Google Translator and a lot of cutting-and-pasting, I managed to muddle my way through their shop and ordered a whole bunch of stuff, including those 4 x 8 mm pager motors and a pile of assorted micro-gears and worms, in plastic and brass. They do ship to the US and they accept PayPal, which made the whole transaction relatively easy (except on my wallet). Will post a report when the goodies arrive.

[Ian MacMillan]

Hummm this stuff could turn out to be what I am looking for to repower my HO American Crane and some Custom Finishing MOW stuff.

[railspike55]

 
maybe will inspire ........you maybe not.

edit for dup content.

Ron

[SquirrelHollow]

I found this a little while ago...

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http://whiteriverandnorthern.net/clinic_35.htm


maybe will inspire you maybe not.

Ron

Those are David's.  Check out the second post in this thread.

[daniel_leavitt2000]

On the first site, the gearhead looks like it will fit on the Kato and Pro-Model 12v micro motors. I wonder how this would affect the slow speed control. The Kato critter only uses about 1/3 of the throttle.

The German site has worms (called snails in German) that are only 1.8mm diamiter. I think this will be usefull for the hi-rail. Now if I can only find a matching worm gear that will fit on the NWSL wheelset.

I think it would be good to complete two vehicles. The first will be the GHQ Chevy. The second will be a Showcase Ford MofW truck with a CinC Chevt cab. Both could be seen on Conrail in the 1990's. The Showcase truck might be a bit easier because I could add working guide wheels that also pick up electricity, giving the truck 8 wheel pickup. I also plan to do this on the GHQ pickup, but need to find wheels small enough.