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Switch Building at Maricopa Live SteamersBy Bill Lowe
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Long before I joined the club, three members, Lenny Rossow, Mel Gooch and Ken Bain, built our switches.
Once a month or so a trailer was brought to Lenny’s home and the new switch or switches were delivered to the club.
They did an excellent job, and most of their work is still in use today at Adobe Mountain Park.
Now to get started. Photo-01 shows the switch jig we use, which is 18’ long and 24” wide. The spacers
are 2 ¼” x 6” and 4” on center. The 2 cuts on both sides of the jig are for the 48” throw ties. I start by laying
out all the ties needed for either a #7 switch (60’raduis) or a #9 (100’ radius). We use #9 switches on all of our
mainline passing tracks, and #7s for yards and stub sidings. All of our mainline tracks have 100’ radius minimum
curves. We are building a left-hand #9 today for the 3rd passing track on the new Far Flung Flats branch, and will
be switch #252 at MLS.
I start by securing the straight stock rail. I pre-drill holes in the foot of the rail, opposite where the rail is milled for the points. (Photo-03) I use a 1” aluminum spacer between the stock rail and the steel bar when screwing down the rail with 1”x #8 sheet metal screws. Where there is no milling, one screw on each side of the rail in needed. Photo-04 shows the straight stock rail completely attached to all ties, and the points lined up and the frog in place with gauges. The curved stock rail is just laid in place for now. Photo-05 shows the points. We use standard 1” steel “C” channel, milled on one side to form the point. Hinge tabs are welded on the heel end and the throw tabs on the toe end using a jig. Because of the length of a #9 point (44”) we use 2 stabilizer bars further down the point to connect both points together to reduce stress. For #7 points (24”), stabilizer bars are not needed. You can see one of the tabs to the right. The machining and welding performed on the C-channel, sometimes results in warping. Prior to installation, I sight down both points ensuring the straight point is actually straight, and put a gradual bend in the curved point. This is done so the transition between the point & curved closure rail is undetectable. | |||||||||||||||||||||||||||||||||||||||||||||||
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The next step is to place the frog. I set the points in place, gauged to the
straight stock rail and measure from the heel end of the point to the point on
the frog, 88” for a #9, 66” for a #7. I get the frog positioned as close to this
measurement as possible, while keeping the tabs underneath aligned with the
ties. Photo-06 shows the frog positioned. Photo-07 shows where I used a router
to cut ¼” of the tie out for the bottom plate of the frog to sit in. Because the
rails bolt to the top of this plate, it is lower than the top of the ties and
some tie material must be removed.
After cutting the closure rails to length, I bolt the points to them. Photo-09 shows the completed closure rails and points, using a 10-32x5/8” hex head bolt and 10-32 nylock nut. All the bolts & nuts used on our switches and rail joints are stainless steel and all nuts are nylocks. The end rails are measured next which will attach to the frog. We use a 24” offset on our switches and track panels. | |||||||||||||||||||||||||||||||||||||||||||||||
Photo 10
The next step is to attach all 4 rails to the frog. I found it easiest to
elevate the frog and rails so I can align the rails, insert and tighten the ¼” x
1 ½” bolts and ¼” nylock nuts, as shown in Photo-10. Photo-11 shows the
underside with the rail and hardware in place. Photo-12 shows the frog back in
place and gauged, and in Photo-13 you can see the frog secured in place with 1
½” #8 sheet metal screws.
The next to the last step is installing the guardrails. In Photo-16 you can see
one end of the guardrail attached. I laid out the parts we use to attach them.
Shown is an 8-32x1 3/16 hex head bolt, 5/8”x ½” spacer, a #8 washer and a 8-32
nylock nut. The screw, washer and nylock nut are again stainless steel and the
spacer is aluminum. We use old worn out rail and remnants cut to 18” for the
guardrails. We cut 2” off of one side of each end at 10 degrees and buff the
sharp edges with a flap wheel. We find this easier and faster than bending the
rail at a 10-degree angle. Both are prototypical. Photo-17 shows the attached
guardrail with track screws holding the inside of the rail. You can also see
where I pre-drill then screw down the stock rail through the foot of the rail
next to the frog (1 ½” #8 sheet metal screws). This eliminates heat expansion
problems during the summer (where it can get up to 125 F at times out here in
the desert). Photo-18 shows both guardrails completed.
Photo-19 starts the throw assembly. We use 1” flat steel bar, bent 90 degrees at
the end with a ¾” brass bushing threaded in to receive the tension springs seen
at the bottom of the photo. The points have a tab welded on the end, with a ¼”
threaded stud pressed in. I hold one point off ¾” from the stock rail and have
the other point touching the other stock rail, mark the throw bar & drill a ¼”
hole for each stud. Photo-20 shows the throw bar attached to the point studs
with ¼” nylock nuts. Photo-21 shows where I have screwed in the throw on the
long ties at the proper distance, pressed on the tension springs, and adjusted
the throw rod (1/4” stainless steel all thread rod) with 2 ¼” nylock nuts and ¼”
washers. Photo-22 shows the throw assembly completed along with the 2 stabilizer
bars installed I mentioned back in Photo-5. All of our switches are designed for
the engineer to look at the throw handle to see which way the train will go. We
also affix reflective tape to the throw handle for night operations.
You will also notice in Photo-21 we use a plastic tie where the end of the
points rides. This is for ease of point movement. Oil will not soak into the
plastic as easy as wood will. You will also notice I have installed 1/64” shims
under the stock rails. This is to add a small gap between the ties and the
points, also for ease of movement. You can see 2 of these shims on the bottom of
Photo-19.
Photo-22 and Photo-23 show the completed switch from both ends. I have inserted
3 - 26” and 2 - 28” ties at the end of the completed switch as the last step as
they do not fit into the jig. Once they are attached this switch will go out on
the stack and I will start another. 252 down, 70+ to go. Ahhhh! Job security at
its finest.
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