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

[DACS]

Here is a pic of the mechanism I will be doing next.  Notice that the rails are not in place.  Also, these were placed before the end beams were placed.  But, it is not too late to still install these, as it is all between the rails.



You will also notice that the NBW's are in place.  Don't worry, this is something that is done later.  The pic you are looking at was the first test table.  So things were'nt done in exactly the correct order.  It all works out.

Dave  HWCRR
Seattle

[bparrish]

Really great...

Thanx
Bob

[DACS]

Thank you Bob.
I do have to apologize to all who have been following this thread.  I posted yesterday that I would be doing the locking mechanisms next, but I cannot find the files.  I had forgotten that they were gone.  Oldtimers really sucks sometimes.  Didn't mean to dissappoint
So I will be continuing on with the table build later today.

When I build the next table, I will take a bunch of new pics, then show how to build the locks.  That sort of puts the horse before the cart.  But, as I stated earlier, the table works just fine without them.  The locking mechanisms are an added detail the table doesn't need to be operative.

Dave  HWCRR
Seattle

[cuse]

Amazing work. Thanks for all of the detail, very inspiring!


John

[deemery]

Here's a good shot of the lock from a Sellers Turntable.


dave

[DACS]

Thanks guys for the input and comments.   Dave, that lock looks great.  I actually built one almost like that.  But it is so small, it is difficult to make it work.  Of course, one could just build it as non-operating.  It would be a great looking detail.  I built the locks on my turntable to operate. 
Is there a prototype of the locking mechanism I built?  Not exactly.   But, I did get close.  I found this pic on the internet after I built mine, and it shows that I was on the right track (pun intended).  This turntable is of the armstrong style also and what I found to be very interesting...dual gauge!



In retrospect, as the pic shows, I could have made the sliding plate smaller.  But the mechanism I built is right on, with just a small difference, which is easy to see.
Very creative use of a switch stand also. 
With the lever system I use though, it is fully operating and works great.  One just uses a totally non scale method of throwing the lever back and forth.  A toothpick or small screw driver.   Because of this, the turntable must always be mounted very close to the front of the layout.  Otherwise, structures and details can be damaged by reaching across them.
Someone once suggested that because it is operating, I could perhaps, activate it with a small servo.  Good idea!  I gave that a great deal of thought and still am.  It can be done, just trying to hide the actuator, is the big issue.
Anyhow,  thanks again Dave, for the pic.

Dave  HWCRR
Seattle

[DACS]

Now, lets make the pedestals for the posts. There are six of them all total.  A lot of text isn't necessary, the pics pretty much demonstrate what is wanted.

They are cut from a .040 x /.250 styrene strip.
I use Evergreen Scale Models #149. (Of which I am not affiliated)
They are cut large enough to be able to file a bevel all around.  This four sided bevel is done on the outboard pedestals only.
The center pedestal, only has the bevel on the inside and outside edges.







Now, even though the center, vertical support beams will stand there on their own, it makes it too hard to keep them there, without them tipping over all the time.
So, I drilled 1/32" holes in the centers of each post, and inserted lengths of 3/32" brass rod.
Cut them so the length, does not stick out at the bottom edge of the main deck beams.







Once all six are made and mounted, I paint them with an oily black water based paint. Once dried, I then use Bragdon Weathering Powders (No affiliation), to give them the amount of weathering I desire.  Do not glue them to the deck yet!



These will just stand there by friction fit for now.  That's what is wanted through the next steps.

Dave   HWCRR
Seattle

[DACS]

Now it's time to make the saddles for the short center gallows post are made from Evergreen Scale Models 3/32" x 1/4" styrene strip. I have lost the number.
Make your shoulder cut at 27/64" or the same depth as the section of beam it rests upon.  You will make two of these.



Using your trusty sharp blade of choice, just carve away to the shoulder as you see here.



Then using either a file or a sanding nail board, bring it to the shape as seen here.



Then make two shallow cuts where the slots are to be. I make mine to the outside width of the gallows posts themselves. That way, the rods will fit very nicely where they belong. Just refer to the drawing of this and you will get the better idea.



Then using an oval needle file, I file down to half the depth of about 1/64". The next two pics give a good show.





Cut it from the strip.



Here is where it belongs.



Paint with flat black and mount with ACC. 



Dave  HWCRR
Seattle

[bparrish]

Dave....

This is so oooooooooooo  cool ! ! ! !

You need to get this judged for AP or I'm coming to Seattle and doing it myself ! ! ! ! ! !

see ya
Bob

[DACS]

Now it is time to bend the center four support rods. Using the drawing as your template, as you can see. Get one end to the correct length, make a mark just above center, then using your trusty x-acto knife handle, holding the wire and knife handle firmly, bend the wire around the handle till you get the correct angle. The curvature is exactly that which is shown on the drawing.





Once done, cut the other end off, using the drawing as your guide.
Make four of these.



Brass is very hard to color, as many of us know.  I always etch brass before I do anything else.  I emerse these into a 100 % solution of ferric chloride and leave it there for at the very least, 30 mins.  Then I take them out and rinse well with clean water.  Then I dry them completely and then emerse them into a blacken-it bath.  I leave them in this until the desired color is attained.  Then take them out, rinse well with clean water and allow to dry.  If any white residue shows up, I just gently buff it off with a very soft cloth. 
Side note: I have a friend who etches the brass with muriatic acid (concrete cleaner).  It does a fine job of it, but for myself, one acid in my collection of chemicals is enough.
Even after all this, it can still chip.  But, it does put up with some abuse.  If it does chip, you can just touch it up with flat black paint or permanent magic marker.
Once this is all done, I then use Bragdon powders to get the rust look, then set them aside.
Sorry, I cannot find the pics for all this, but hopefully I have explained it clearly enough.

Next, we make the small tabs that go on the underside of the table. These are what the rod ends pass through with the adjustment NBW's on the ends.
Here is a deviation from the plans.  I have 16 tension rods, whereas the drawings show only 8 tension rods.  That means there are only 8 of the angle plates.  As mine has the 16 rods, that means there are 12 tabs to make. 
Eight of these are made of 1/4" x 1/4"  scale lumber, to a length of 1/2" .  Four are cut from 1/4"x1/4" scale lumber, to a length 21/64.  Once these are cut, we then split them, so that you have two triangular pieces from each. This will give you a total of 12 pieces.  8 are 1/2" in length and 4 are 21/64" in length. Remember, this measurement is based upon my table using the 6" wide scale lumber for the side beams, rather than the 8" shown in the drawings.





These will be placed exactly where I show in the pics. Now is a good time to stain and grain these pieces.  It can be done later, but it is easier to do it now.

Here are two of the 1/2" tabs placed in their proper locations.  Two more are placed in exactly the same location, on the other side of the center support cross ties.   Place these tabs so the center line is split evenly on both sides of the side beams. 



The next four are placed in these locations.  Two more are placed in exactly the same location, on the other end of the table.  Notice the tie count between the tabs you just placed and these.



The four smaller tabs are placed on both ends of the T/T, in these locations.



It is identical on the opposite end of the T/T.



I have got to break away for just a bit.  When I return, I will show how to drill the holes properly.  As you can see, I did not do a very good job of it the first time.  Now, that I am doing it the way I am showing you.  It comes out a whole lot better.

Dave  HWCRR
Seattle

[DACS]

Hey everybody.  Sorry, it has been almost a month since I last posted anything on the turntable.  As I have said before, life has a tendency to get in the way of the important things.
Bob, in response to your question about the box car, it is a scratchbuilt unit.  I was experimenting with making a frame for 18' cars.  The frame is used to make the box cars, flats, and gondolas for the Horace and William Creek R.R.'s fleet.  That box car you keep seeing, is my test bed.

Now on to the t/t.

Here is where I made another deviation from the plans in the Annual.
I have many pics of gallows turntables; they all have more support rods, than the turntable build instructions show in the prints.
The instructions show only four rods. One on each corner, and then the two on each side going over the lower center support beams.

I am going to do it as the pics show with prototype t/t's. They all have 16 rods.
There are the two each side, lower supports rods.
There are four intermediate support rods farther outboard, on all four corners.
Then, they all have the one support rod for each corner.
This is a total of 16 rods.
Here are a couple of pics to show the orientation of the support rods.





This deviation is no big deal.  I just make upper supports that have 3 slots each rather than just the one shown in the annual.

All the rods, which we make later on in the thread, are made of .020 brass rod/wire.

Now, we can move on to making the upper saddle plates where the bent rod pieces are attached and where the support rods will terminate and attach.

To make these, I use pieces of 27/64" x11/64" scrap wood. I file and slot, just like was done with the lower support saddles, using the same tools.
I make two, one for each side.

Sorry, it's not the greatest pic showing this.
But, there are pics coming up that show you a better example.



Once these are cut, I use .032 solder, to make the bent termination rods for them. 
The flexibility of the solder, makes it very easy to get the shape you want and it bends very easily. You can do it this way, or with brass rod. This is just the easy way for me to do it.  You can do this any way you choose.



Next, will place a couple of T pins into a piece of foam core board.  These are spaced according to the measurement in the pic.
This is the jig for make the rods.



This is pretty much what we are wanting. You will make six of these.



Cut off a piece of the solder so it will go around the pins on either end.  Make them longer than needed
Using the jig is a very simple matter. Just wrap the solder around the pin tightly, then give it a slight back push to give the offset, then do the other end the same way. If it is too long on the end, all you have to do is use a razor blade to nip it.



Once you have them all cut and the eyes in place, you will have three per plate.



Just ACC them centered, on the plate as shown.



Now you can paint and get them ready to mount. The only thing that is fastened together permanently right now, is the solder rods you just made.
The gallows posts are not yet fastened to the bridge. The top beams are not yet fastened either. The saddles you just made are not permanently fastened either. Everything, if done right, is just a good friction fit.
Here is where they will reside.  Yes, the paint is chipped, solder doesn't hold paint well.  This can be touched up later, once they are permanently mounted.



Next I will be fastening the upper ring rail beams and rail, to the bottom of the T/T.  You will see now, why I stressed accuracy when we first started building the T/T.
That's why I use a jig.  Mounting a turntable can be a difficult task. 

Dave HWCRR
Seattle

[S&S RR]

Dave

I stopped by tonight for my latest installment of your work. 
All I can say is keep up the great work - enjoying the tread. Thanks for posting.

[cuse]

Very cool. At first, I figured witchcraft...but you've done a great job explaining.


Really nice...John

[DACS]

Thank you John and John.

Perhaps, I am only doing an SBS as a cover John.    Maybe I am wiggling my nose or...perhaps I am crossing my arms and nodding.

Anyhow, today I am going to show how I center out the upper rail beams.  Also how this centers where the main shaft will be planted and lines everything up.
This may seem like a lot of extra work, but the alignment of the turntable is a critical component of it's working as you want it to work.  Nothing more disappointing to go to all the effort of building something like this, getting it installed then finding, the entrance and exit rails do not align.

To begin with, I first drill a 1/16" hole, all the way through,  in the center piece of wood we planted earlier in the thread. Between the center cross beams.  The accuracy of dead center for this hole, I cannot emphasize enough.  This same hole, will later be enlarged with various sized drill bits, to mount the main center shaft.
I had to take a couple of shots at it.  (The finding, not the drilling.)  The latter, you have only one shot at it.



Next, the jig for centering the rail beams is to be built.  All the measurements for this little device are taken from the On30 Annual drawings.
The outside dimensions that are between the flats are shown here.





I used balsa to build this jig but any material can be used.  Also, the tube is 1/16" aluminum tubing.  Just what I had on hand.

First, cut out a square of your material, that is the same as the inside measurement of the beams.



Carefully find center, then drill a 1/16" hole.  I know, it looks off center, but it isn't.  It is just the fuzzy nature of balsa causing that appearance.



Then I glue in the piece of tubing.  This one is 2 5/16" in length.  Then the triangular pieces that are removed, are glued to the tube and the base, to get the tubing square.













The jig is then placed into the hole you just drilled in the T/T.



Next, the actual rail support beams are made.  I have glued the actual patterns to the individual pieces here. The opposite side is already grained and stained.  This makes it easier to show how to do this.  Once all this is put together, the unit can be turned over so the paper does not show, once you stain the paper with the A/I.



Each piece has its own pattern and is cut accordingly and ACC'd to the piece preceding it.  Once done, set it aside with a weight on it and give the glue plenty of time to set firmly.

Cut the pattern pieces carefully and glue to the back surface of the beam pieces.







Once the unit is well set, then place it over the jig.  I am leaving the paper side up here, for better clarity on what it looks like.  Once you are satisfied, glue then entire unit onto the bottom of the T/T!



Once the beams have set nicely, remove the jig and voila'!  You are now ready to fasten your ring rail to the beams.

I hope I have made this more clear than mud.

There ya go!

Again, for those of you who have built T/T's and found at the end it did not align, I believe this method cures this heartache.  It did for me.
If you have a better way, then please share it here.

Dave  HWCRR
Seattle

[LoggerMike]

Dave,  I have questions regarding the Base Ring changes you made.  Although I am building the TT in HO, I downloaded the ON3 pdfs for it like you suggested.  However, you stated that you changed the dimensions of the Base Ring to 4-3/16" across the Flats...When I measured the pdf, the Base Ring there is 3" across the Flats.  The Bridge itself is only about 3-5/8" wide at the center Beams that ride over the Ring.....When I look at your pictures, it appears that the Ring is tucked under the Bridge....leading to the question.....Did you also widen the Bridge too?  I've read this forum article at least 10 times...Did I still miss something?  Just trying to get a handle on the Scale differences and the appropriate measurements adjustments based on the Scales.

Mike

Charlotte, NC area