Building a Gallows Turntable for the Horace and William Creek R.R.

[DACS]

I had looked for a long time, trying to find a gallows turntable in kit form for the HWCRR.  For one very large reason, they don't exist.  Not to mention the size I was wanting.  Neither does the spider assembly that it rides on.   So....
Break out the paper the tools, glue, wood, cardstock, plastic and lots of patience.

The spider assembly is my design and engineering ability in total  It is also fully functional.  Another part of the table that was designed by myself and  fully functional, is the locking mechanism on either end of the table.  This is, of course, something one can add or not.  The table operation does not depend upon its even being there, but, I had to prove to myself I could build it as a working locking mechanism.   The turntable itself, is a general design of a gallows turntable.  It was gleaned from pictures and other info I could get from the internet.

Here are some pics of what will be built in this thread.

The first part of this build thread, will be making the fully functional spider assembly.
The second part will be to build the table proper.
The third will be to make the locking mechanisms.  This is last because as I said earlier, they can be added or not.  It is entirely up to the decision you make.

This is where it is supposed to end up.



Enjoy!

Dave  HWCRR
Seattle, Wa

[S&S RR]

What a great way to start - I will be following along.

[gnatshop]

This is an awesome Gallows Turntable!
You've already been accepted in the 'Ledbetter's Hall of Fame' for build it with what you've got! 

[rustyfawcett]

Looks great.

[bparrish]

Rusty


I scratch built two gallows turn tables about 25 years ago. I gave one recently to another modeler. I used an old RCA quarter inch ear phone have and receptical to center it get power up into the rails.  One wire wind up.

See ya
Bob

[postalkarl]

Hi:

Very cool. Lots of nice detail. Keep the photos coming.

Karl

[rustyfawcett]

bob that would fit nice on my layout. I my have to start planing one

[clevermod01]

That model looks great no matter where you look. beautiful work.

[DACS]

Guten Morgan y'all.

Thank you for your support and enthusiasim John, David, Rusty, Bob, Karl and Thom.  Hope I got everyone.  If not, it is not a deliberate omission.

Stage 1:  Contructing "THE SWEET SIXTEEN SPIDER ASSEMBLY"

Tools:

* Dremel Drill Press
* 1/16" drill bit
* small V-block
* Needle files/flat and round
* Razor saw and mitre box or use a tubing
cutter. (The latter makes a much better
and easier cut for the tubing.)
* Single edge razor blades
* Wire nippers
* Tweezers
* Chopper
* Ruler
* Compass
* 1/4 or 1/8 graph paper. 1/8 is better.
* ACC
* White glue (for the wood part)
* Paint and weathering powders

Materials:

* 1 K&S 5/8" pt.#143 brass tube
* 1 K&S 13/32" pt.#136 brass tube
* 1 pk. K&S 1/16" pt.#1800 aluminum tubing
* 1 pk. K&S 1/8" pt.#1802 aluminum tubing
* 1 pk. K&S 1/32" pt.#8160 brass rod
* 1 pk. Evergreen .020 x .125 plastic
strips pt.#126
* 3 Nylon or hard plastic bushings or
spacers...12mm O.D.x 10.4mm I.D.
x 3/8" h.
* 2 1 1/4 x 3/8 flat washers
* 3 13/16 x 3/8 flat washers
*16 metal axle HO scale freight
car wheelsets.
* Stripwood necessary to build
the upper and lower rail supports and
base.
(Same sizes as required as per article
in the On30 annual.)

Here is a pic of the subassemblies that make up the spider.  It is not as daunting as it looks, so plunge in.
During the build, if you have any questions, please ask.  If you think it can be improved, please post. 
This unit has been in operation now for a year and it operates flawlessly.



The first thing to be built, is the base.



To make the lower cross beams, go to this link, then print up the pdf files:  http://on30annual.com/extra/on30_extra_gallowsturntable.php

They print out full size for On30.  I will not show the actual printing here as I do not want to get into copyright issues.  Once you have the drawings, you can cut the lower support beams from the patterns you have from the printing.  Important note here.  Once you have the base beams in place, find absolute center now!  Very difficult later!

Once you have all your pieces cut, you can begin to assemble the lower part of the spider support assembly.  If you will go to page 5 of this thread, you will see where I pick it up again and build another base and rail support assembly.  You will see that I use the actual drawings, cut and glued to the rail base support beams.  This was the first one I built and it was a tough go.  The second one I built is again, on page 5 of this thread.  I am making this edit because a new member (Mike) caught a mistake on my part.  So, I have come back in to correct my error.  The picture with the error was in this location.




You will notice little nibs on the corners.  Do not worry about these.  Once the subassembly is built, you can just file or sand these flush.

Rolling the rail can be done many ways, I will pretty much leave that up to you.  I used the bottom of a plastic bottle to wrap the rail around.  To get it perfectly round, I actually over lapped then cut.  Voila' , one ring rail.  Make sure your ring fits center of the base planks.  You can make a gauge and use that.  I do not have a pic of this.  So sorry.

Once this is finished, it is time to build the actual spider itself.  I promise, I will make every attempt to post the spider assembly today.  I have to download all the pics and get everything ready.

Dave HWCRR
Seattle

[GPdemayo]

Really great Dave.....thanks for sharing!

[DACS]

Thank you Gregory.

That's quite a title:  General Construction Superintendant.   Is that your professional Title or is that the title you use on your model railroad?  As the railroad is in Florida, and it carries the monaker Denver within it, I am going to go out on a limb here and think it is the name of your railroad. 

Back to the Sweet Sixteen Spider Assembly build.

Now to begin the center hub for the wheel assembly:

Using a fancy indexing tool...Cut a piece of your graph paper in one, 1/4" wide strip, by 8 squares in length. It is critical that you cut it out exactly. Before you stick the tape to it, wrap it around the tube to see how the ends come together. It may take more than one try, but, it must be exact. Same if using 1/8", only you will count off sixteen. Using the 1/4", you will have to make some extra marks so you come up with 1/8" ctr. points along the entire strip. Using 1/8 graph paper, this step is done away with. 1/8 graph paper, also makes a much better job of it.

Once you have done this, place a piece of clear tape over the strip and wrap it around the 5/8 inch brass tube on the very edge.



Now you are ready to begin drilling 1/16" holes all the way around the tube. Also note that if your holes are off center just a micro, up, down or even sideways, it won't matter. Just don't let it go drastic. You can make up any differences, later on in the build.



Once done with this, you will then remove the index paper and cut the piece you just drilled, off the brass tube. You want it to be 1/4" wide. It is not that critical though.

Once you have cut this section from the tube, clean out all the burr's there might be present, with your round needle file. Then you will place it on one of the nylon bushings. You want it just a smidge above center.



DO NOT USE ANY GLUE HERE!


I will let you know when it is time to start using the sticky stuff.


Don't know what a smidge is, but it ain't much. This is so you will have some slight downward pressure on the center hub, keeping the wheels tightly to the rails. You'll see what I mean when it comes time for that. It will all come together in the end for ya.

Now, holding it firmly, drill your first hole through the bushing using the brass ring as your template. Do not try to go through both sides sides of the bushing.

Once you have that first hole drilled, push a small piece of 1/16" aluminum tubing all the way through, to the inside of the bushing. This will hold the ring in place while you drill out the rest of the tube holes in the bushing.





Now drill out the rest of the holes. Then clean all the burr material from the inside of the bushing.

Cut all sixteen axle tubes with your trusty single edge razor blade from your 1/16" stock. I do this by just rolling the tube across the work surface with the blade, with downward pressure. The tubes are 1 1/16" in length. Once cut, clean up the ends with a light filing to remove the little ridge that appears. Do not go overboard with this, or the fit in the hole will be to loose. Place the first tube into one of the holes. Push it to where it is just short of coming all the way through to the inside. Then remove the aluminum pin you had holding the ring in place.
Then follow suit with the rest of the tubes until all sixteen are in place.



I think I read somewhere here, that we can only place a maximum of six pics in a posting.  So, here is where I will pick it up and continue on a little later.

Dave HWCRR
Seattle

[DACS]

Set the above assembly to one side and begin making your wheelsets.  A slight notation here...it has been said to me, that no one has ever seen a prototype with flanged wheels or rollers.  Well, now you have.  If I build it, it's a prototype.  My engineers may be a little odd sometimes in their applications, but they use their vivid imaginations and use readily available materials.  Nuf said!

I am using HO scale freight car wheelsets that have a metal axle.



Remove the wheels from the axle and put the axle into your parts bin for some future other use.
Now you make the bushing that goes into the wheels. This is made from the 1/8" and the 1/16" aluminum tubing.







Notice the wheel orientation on the tubing. Now we use some acc to bond the wheels to the tube. I put acc on the tube between the wheels, then little dabs on the wheel facing edges.



Then cut the tubing flush with the back of the wheel set.  Do this to all sixteen wheelsets. 



I shall return

Dave HWCRR
Seattle

[DACS]

Once you have that step done, you are going to start all over with the 1/16" tubing. Slide the tubing all the way through the 1/8" bushing you just finished. You will want enough sticking out on the other side, to put some acc on, then you will pull it back into the wheelset, leaving 3/32" of it, sticking out on one side.



Then again with your razor blade, cut the tubing flush with the back of the wheelset like you did before. The side with the short extension has now become the front of your wheelset. Repeat this for all sixteen sets.



Once finished with this step, you have to start over once again.
From the 1/32 brass rod, cut sixteen 1" pieces, these will become the axles.
you will need to clean up any burr's, so they will go through the bushings you just made.
Putting some acc on one end of the rod, push it into the wheelset until it is flush with the outside edge of the tubing. Do all sixteen wheelsets the same.



Now, just for grins and giggles and to admire your work, you can put all wheelsets into the hub/axle housing unit.  This is just a temporary look see.
Remove them and get ready to paint and finish them.



Dave  HWCRR
Seattle

[bparrish]

This is sooooooo cool. 

Thanx
Bob

[DACS]

I paint the outside and the tread area with Polly S Oily black. Once this has dried, I mix up a very thin wash of Polly S Rust. Then wash down the wheelsets with this.
Try to keep all paint off the 3/32" shaft coming out the front of the wheelsets.



Once dry, I will then use Bragdon bright rust.



Then, over that I will brush on some Bragdon black. Not enough to cover the rust, but just enough to push it back.



Dave HWCRR
Seattle