Blade with curved tip
Jig
Styrene channel with concave recess scraped into flat side
The author made a jig from styrene to hold Evergreen .080″ channel while a concave re- cess was scraped into its flat side, the first step in making the connectors for the silo bands. An old No. 17 blade was ground to shape to make the required tool. The edges of the channel were rounded slightly, then short pieces were cut to represent the fittings.
(Remember, I had just built a bath- room.) While this approach worked, too much PVC pipe cleaner melted the Evergreen siding, and it had to be glued to the pipe a little at a time and held in place with a variety of home- made 90-degree V-blocks and wood- working clamps. Thinking there must be a better way after joining two sheets of V-groove sid- ing together edge-to-edge and cutting them to 7¹⁄₂″ wide, with the second silo I scribed grooves across the sheet to help hold the bands in place. I used the back edge of a No. 11 knife blade for this, plowing flat-bottomed furrows. This resulted in a lot of styrene “fuzz” that had to be removed. By drawing the edge of a single-edge razor blade across the siding I got rid of most of it. By all means, don’t use a brass-bristle brush, as it scratches the siding (which would be fine if you are building a weathered wooden structure). Next, I glued the scribed sheet to the PVC pipe with Weldwood®
contact ce-
ment. I brushed a half-inch stripe of contact cement along the length of the pipe and a stripe of it on the end of the siding and waited for it to dry. Then, on a piece of plate glass, I stood the pipe upright and brought the edge of the siding into contact with the cement on the pipe, making sure the bottom edge of the siding and the pipe were both flat against the plate glass and square. Once these two pieces are together they will never come apart! Then I brushed a thin layer of con- tact cement on the rest of the pipe and siding. After it had dried I simply rolled the siding against the pipe on
RAILROAD MODEL CRAFTSMAN
the plate glass. When you do this, just make sure the pipe and siding are square to each other so the scribed grooves for the .020″ bands line up. (If they don’t, you can still hide the mis- match where the silos face each other.) The next step is to cut a bunch of
.020″ styrene rod 2³₄″ long. A North- West Short Line Chopper makes fast work of this. For each silo you build you will need two packages of .020″ diame- ter Evergreen rod. If you want, you can pre-bend the ends of all of these rods, one scale foot long, one end up, the oth- er end down, or you can just “fake it” as you go along. The advantage of pre- bending is that you can make a fixture so all rod ends are uniform. The disad- vantage is time; 38 bands per silo times three segments per band equals 114 bends. You could just bend them as you go. The advantage of this method is that it goes quickly. The disadvantage is the pieces will probably not be uniform. A third way to make the bands is to take three pieces of the rod, glue ¹₈″ of the ends together in an over-and-under fash- ion, then reinforce the two joints with band connectors. After the glue is dry, give the rods a bit of a downward bend to the left of the connectors and the same amount of bend upward to the right of the connectors so that they are all in line with each other and the connectors are a bit twisted out of horizontal. Glue the bands in place in each groove around the perimeter of the silo, joining the free ends with another con- nector. Trim the band ends so the same amount projects beyond this last con- nector as they do with the other ones.
Band connectors I tried a couple of ways to simulate the band connectors. With each way, I asked my wife to look at a photo of a real connector and my attempt at sim- ulating it. After a couple of “close but no cigar” comments from her, I hit upon a way to make connectors that look reasonable, though a bit large. By taking Evergreen .080″ styrene chan- nel and scraping the flat side slightly concave and rounding off the edges, a scale six-inch length glued over the joint between the .020″ rod ends looked pretty good.
There are 114 connectors on each
silo, so making a total of 456 of them one at a time was out of the question. Even casting these “fiddly bits” in resin would be very time consuming. I finally came up with a mass production method. To hold the channel while working
on it, I made a fixture on some flat styrene sheet using a couple of lengths of .125″ square styrene and Evergreen No. 8406 HO scale 4″×6″ strip styrene. First, I laid the 4″×6″ strip between the channel legs and carefully glued the 4″ width of the strip to the sheet styrene. Then, I placed one piece of the .125″ square stock against one leg of the channel and glued it to the sheet. After a few seconds I removed the channel just to make sure it didn’t get glued in place by an errant drop of ce- ment.
Afterward, I put the channel back on top of the 4″×6″ and placed another piece of .125″ square styrene against its other leg. I glued this strip to the sheet as well. (The resulting slots be-
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