Tuntable pit

<font color="336633">What does the pit of a turntable look like? Im mainly thinking of the later days (in the 80's) did they get over grown? were they concreate? etc.

thanks </font>

 

WATASH! HELP!

 

Both CN and CP had turntables and roundhouses here in Toronto. The CN one is gone but the CP is still there. They were both made of concrete. While active, the floor of the well would collect grit and some puddles but were generally fairly clean as the cicular guide track had to be kept in good order. The CP one isn't used for anything anymore and it is full of grass and weeds.
Here is one in Montreal from CNR archives.

 

<font color="336633">Ahhh Robin, another question, how did they keep snow out of turntable pits in Canada (or northeren US)?</font>

 

Good question Stickymonk, I can only guess that with a ready supply of steam and a good drainage system that snow would not last long in the well

 

Not the same topic but the track in the Toronto terminal area has a large number of single and double slip switches. As a GO commuter going through this area during winter months, I could always see a team with oil torches melting the ice buildup on these switches so I am sure they would be inovative enough to deal with snow build ups in the turntable well

 

All turntable pits had drainage, some into a sump where pumps would remove any accumulated water. Snow and ice were thawed with steam, and snow was shoveled out. I have seen a photo somewhere of a pit that had a ramp for a truck to be driven down in to haul out trash. Leaves in the fall, snow in winter, and spare parts to repair the motors and dollies under the turntable. I have a book that shows how a typical turntable and pit are supposed to be built. I can post the page, ot send you a copy if you like. I don't think you would want to try building the center bearing post in N scale though! HA!

 

<BLOCKQUOTE>quote:</font><HR>Originally posted by watash:
I don't think you would want to try building the center bearing post in N scale though! HA! <HR></BLOCKQUOTE>

<font color="336633">Thats ok im in HO </font>

 

This site has pics of a late 1980's table and pit of the SP.
http://espee.railfan.net/sp_truss_turntables.html

 

Whats a good way to build (model) an HO scale turntable thats 20 inches in diameter, big enough to turn a big boy or as my big boys are a EM-1???? I can compromise that to 18 inches but thats just at the wheels of the tender and the pilot wheels on the loco itself. But I would prefer a 20 inch one though.

Can't anyone help???? Watash I know you got a few tricks to add

 

John, one way I would go is to use a router with the circle cutting rod and centre and cut thicknesses of plywood to make the depth you need. EG two 3/4 inch thick sections of plywood glued together would give a depth of 1 1/2 inches. With a router you could easily cut circles with a diameter of 20 inches. I got my router and accesories like circle cutters from Sears.

 

Yes I could tell you John, but it would cost you a bundle for the feasability study! Then you would have to decide where the center of this pit is going to be, and drill a 1/4" hole through the table top vertically. Then you have to cough up a router with a circle attachment on it, set it so that the 1/4" dia. straight side cutter is short of the 10" radius by 1/8". Then I would have to make out a 3 page report advising that you have a master certified cabinet maker mount a piece of 1/2" by 16" by 26" cleat under the table, with four wood screws put in from below and centered under the center hole you just drilled. It would go on to suggest you drill all the way through this cleat using the center hole as a guide. Then you would want to also put four wood screws down through what will be a round plug when you cut the pit wall. Leave 2 inches clear inside the wall diameter and counter sink these screws. The design of the turntable would have to be up to you. Once you received the prints, you would know how deep the pit has to be, and if it has a slopeing bottom, or a flat bottom. You would of course want to know the height of the shelf the pit rail will require and make allowance for that step. When you obtain the funds from the Board of Directors, you would want to delegate someone to cut a blank of wood large enough to extend an inch and a half beyond the pit wall all around, and thick enough to provide the depth needed. Again you would drill the 1/4" center hole vertically through this block in the center. To save alignment problems later, your crew chief is smart enough to mark one end of the cleat, and the under side of the table and remove the cleat. Then he would slip a 1/4" shaft in the cleat and block and rotate both so all edges are parallel. He would then also mark the block and put the shaft up through the center hole in the table and insert four long wood screws through the cleat into the bottom of the table, but not through the block. He would put two short screws through the cleat and into the block from below. Now by removing the assembly from the table, it can be dissassembled and the block can be centered on the table center hole with the 1/4 shaft. Align the edges of the block as convenient to miss any bracing or cross members under table, and drill a 1/4 hole at opposite corners of the block set back from the corner 3/4 inch each. Drill through both table and block vertically. Use a lead pencil to lightly mark the table top all around the block. Remove and install the block under the table using the corner holes and replace the cleat using the aligning marks, and a shaft all the way through the table, block, and cleat. Install the four long screws in the cleat, and tighten. Now I collect my first check. We will all meet at the pit in the morning and finish up.

[ 11 March 2001: Message edited by: watash ]

 

Good morning crew, (Jan had to check E-Bay).

Now set the router so that the cutter can be plunge cut down to about 1/8" depth, and make a climb cut all the way around to point of begining. Repeat plunge cuts until you almost reach the depth of the shelf for the pit rail and stop. Reduce the radius by .188" (3/16") and repeat to same depth until you have reached a radius smaller that the step is wide. Now set the router at the full radius you need the pit wall to be, and make a plunge cut no more than 1/32" deep. Make a climb cut all the way around slowly. This will cut clean and will not raise splinters to mar the edge. Make plunge cuts until you reach the original depth at the shelf before. Check the depth, and make a plunge cut at the radius of the shelf width. Remember the diameter of the cutter! Make plunge cuts down to the depth of the pit floor at this point. Now go back up and set for the full depth required for the shelf. Climb cut all the way around on the shelf from the inside out in stages until you reach the wall, but do not enlarge the wall diameter. Now is a good time to remove the block from the table, set it aside and remount the cleat. Put the four screws through the center plug and into the cleat using the same original holes. (To prevent damageing the threads in the cleat, it is wise to rotate a screw in reverse by hand so that when you feel the screw drop into mesh you stop rotating and rotate the screw the other way until it gets too tight to turn by hand. It has found the original thread, so you wont cross thread and weaken the wood). With the center table plug in place on the cleat, you have maintained the exact center and can align all stall tracks with precision to dead center. When the turntable is installed, it is a simple matter to mount both ends of the table track in perfect alignment with a stall track, fasten in place, rotate the turntable 180 degrees, and align the other end to align with the same stall track. Now alignment is guaranteed to any stall track chosen. The router may be used to hog out the rest of the block for pit floor, or if the block is the proper thickness, the center may be band sawed out to suit. A light coating of sander filler will fill the wall and shelf for painting.

Now you can get fancy and mill the ties in the shelf for the pit rail, or glue them in place. I prefer to glue them in place, then using the router again, make a light cut with a 1/8" diameter cutter to cut a perfect circle for the pit rail to sit in after rolling to shape and cutting to length. Do relieve material for a joiner if used to prevent having the rail hump up at the joiner. If you plan to bandsaw the block bottom out, make the cleat large enough to cover the hole left, and mount the rotating mechanisem on that, and you are done with the pit. Now rip a strip of wood as wide as the ties or roadbed you will use for stall tracks, and long enough to reach from the rear wall of your roundhouse and to an inch beyond the center. Pull the strip away from the wall 1/4" and mark the other end of the strip at the center hole and drill a 1/4" hole through in the center of the strip. Slip the center shaft through this strip and into the center hole in the table plug, and center the strip in each stall doorway. Use a lead pencil to mark along both sides on this strip for each stall and any other tracks to the turntable. This saves a lot of surveying. Now Pay me!!

[ 11 March 2001: Message edited by: watash ]

 

For the price of that survey Pictures would have been nice.

 

Watash,
I'll get my router all ready I have a friend that his dad owns a cabinet making shop so I got ways to get the tools.

But i'm going to start this and I understand everything up to this point. My major question is the turntable bridge, if I scratch build a turntable I am not real sure how to go about doing the bridge itself. I know this so far that the electrical frame post thats in the center i'm going to bend from brass tubing. And the rest so far on the frame is undecided. But as for the bridge i'm not quite sure how thats going to be done. That was my main question that I did not state very well, and should have. I got the ways to build the pit itself but the bridge and the operational components was my actual question...

[ 18 March 2001: Message edited by: 7600EM_1 ]

 

TC and John, I'll have to get my slide rule for this, and it will cost over time!!

Go to the Free Landers Forum. Set the "Show topics for XX days" to 'Last Year', then click GO.

Now scroll down the Page #2 until you come to: Welcome to the Lancers Board topic, click and scroll down to my post on 14-10-00 where I posted a photo of the roundhouse, and just below a photo of the turntable under construction. Also you will note there is an e-mail address for Mr. Neal Wolfe who furnishes kits. I strongly suggest you contact him and request his catalog, it is quite extensive for N, HO, & O engine terminal accessories for steam and diesel. The kit comes with the power tower which actually carries current to one rail while the pit rail carries it to the other rail. Follow his instructions, and use the template he furnishes, and the table glues together square and straight. I am leaving the tower and hand rails off until I have aligned all 33 stall tracks, which I am laying at present. The pit, turntable and fittings was a total cost under $200.00 and I am very well satisfied with all of it.

 

TC and John, photo worth 1K words...
This is the roundhouse right after cutting the pit hole with the plug still in place for aligning stall tracks. The box car will give you an idea of the seven foot diameter of the roundhouse! 33 stalls.

This shows the turntable construction. Note the ties are laid out on the template furnished with the kit. Over all length of the turntable is 18-1/2" which clears my 4-8-8-4 just like the real one at Cheyenne. The pilot and a couple of feet of the tender actually hung out over the ends of that turntable. It was 134 feet long!


[ 14 March 2001: Message edited by: Colonel ]

 

This shows my N gauge roundhouse under construction. The pit is big enough to handle my 2-8-8-2 Mallet. You can see I have extended 3 stalls for larger locos.