Not sure if that helps or not. Besides that you need room for the weights to hang. They don't need to hang as far down as what is shown in the video but still more than the distance for just the mechanism shown above. I haven't put the levers through a trial run yet. Will try and do that before next week and get the files up for them along with the push/pull controls. Sumner
Sumner, How are things? I read you are getting a new printer. You have a lot of irons in the fire! Will you be putting up the gravity switches soon? Thanks, Scott
I guess it was a long 'next week' from Jan 7th until now but I just spent the last 4 days designing some new parts for this project and then documenting everything so that it might make some sense and then uploading all the print files (lots) to thingiverse.com (which isn't fun as they are having problems). The end results are that the files are now all posted along with the documentation on my site. Here is a link to the menu with links to the individual pages on the switch machine, a Push-Pull control, a Lever control, and pulleys and line adjusters to route the control line from the switch machine to the control at the edge of the layout.... http://1fatgmc.com/RailRoad/Trackwork/Trackwork-Index.html Here is a video of the initial testing... For those that are new to this thread I've designed what I call the Gravity-Switcher switch machine. It gets its name from gravity working on two equal weights that are on two unequal length lever arms. Lift the weight on the longer lever arm and the switch machine throws the turnout to the opposite position. The mount and arm that has the music wire inserted in it are very similar to servo switch machines that I and others have designed and made available. This one uses no electronics and operates with a simple piece of mono-filament fishing line running to the edge of the layout and any number of means available to pull and hold it just enough to lift the one weight. Lift it higher than needed is no problem, thus the lifting mechanism doesn't have to be very accurate. You could pull the line and wrap it around something but there are better options. I'm hoping that as people use this they post their solutions to pulling and holding the lifting line. Also you can adjust the pressure on the switch points by which hole you put the music wire into on the switch machine arm. There are provisions as shown above for also controlling the frog polarity or something else with a mount for a limit switch. Here is a link that goes into the switch machine itself in more detail..... http://1fatgmc.com/RailRoad/Trackwork/page-26.html I've presented for now (more options will come) two options for controlling the lifting line. Shown above is a Push-Pull Option. It also has the option of controlling the frog polarity or not. Here is a video showing it on a test setup. Also there is a .... ... 'Lever' option to operate the switch machine. You also have the option for frog polarity control or not with it. .... and ... ... these could be ganged together. I have some other ideas for simpler controls that I'll post about as I come up with them and be sure and post what you have come up with for the rest of us to see. Here is a video of the lever controls being tested.... I've also made print files for brackets, pulleys and line adjusters .... ... to use with the control line that go from the switch machine to the side of the layout ..... http://1fatgmc.com/RailRoad/Trackwork/page-29-a.html You can find the print files on the links shown above or on my thingiverse.com account here .... https://www.thingiverse.com/sumner/designs Sumner
I also tested a simple 'eye hook', as shown above, as an alternative to a turning pulley and it worked fine. If it worked in this test where the line comes back on itself almost 180 degrees I feel it could work easily on lesser angles and you could even use a number of them to get from one location to another. I would use one that is a little more expensive like shown above that is larger and smoother for less friction on the line. Sumner
This is by far the easiest method to operate the Gravity-Switcher. Also requires the quickest print time for the parts. One can also come up with their own parts to do the same thing. The only drawback might be looks and the fact that this doesn't have the option of changing the frog polarity at the edge of the layout like the preceding controls can. You can still change the frog polarity at the Gravity-Switcher with a SPDT switch mounted to it. Most will probably do this anyway as the wiring to the frog then is very short. The piece above goes through the fascia on the layout's edge. It has an inside chamfer on the side the line comes out on to help protect the line. Clean it up a little if needed after you print it. To activate the switch machine you pull the knob assembly out and down and hook it onto a screw to hold it in that position. Where you put the screw isn't critical and could even be to one side or the other of the fascia piece. You need to have it far enough that when connected the weight at the Gravity-Switcher is lifted. It doesn't matter if you over-lift the weight. A major nice feature of this setup is that how the line goes to the switch machine and how far the weight is lifted is not critical. I indicated above how the line is routed. After you glue the knob on the first part of the know assembly run the line through the hole and down the round column and out the back side. At this point use a piece of mono-filament line 4-5 feet long. I wrap one end a time or through a 2 mm sterling crimp bead (cheap on Amazon) and then crimp the bead to hold the line.Next your run the line through the fascia piece and towards …. … a line adjuster. Take the slack out of the line (see preceding page) and you are ready to use the Gravity-Switcher. This line would go into the adjuster shown above from the right side. The line on the left side goes to the Gravity-Switcher. Very simple setup. There are lots of other ways one could basically do what was described above. For instance, a round metal ring that you pull out and down and hook onto a screw. Let me know what you come up with. For a video that shows the 'Knob Control' on a test of the Gravity-Switcher go ( HERE ) or click on the picture above. You can find the files to print the items on this page only ( HERE ). You can find all the files to 3D print this object and others on my thingiverse.com account ( HERE ). Link to my web site here.... http://1fatgmc.com/RailRoad/Trackwork/page-29-b.html Sumner
Sumner, Printed out some of the parts, enough for testing anyways. They were printed on a Lulzbot TAZ. I only had one part with an issue, and that was with the tip of the short drill jig. I built a test jig and have to finish modifying a switch before I test.
http://1fatgmc.com/RailRoad/Trackwork/page-26.html Mine printed ok but I've had problems at times with something that small that far off the print table. Usually it is because the print becomes loose on the print surface and moves around. I then make sure the table is level so that the first layers are adhearing well and sometimes also go to a "Raft" under the print to make sure it is really held well .... .... like in the picture above. Thanks for getting back on this and Let me know how the testing goes. I believe the Gravity-Switcher can be a viable, cheap, easy to use, turnout control option. So would like to keep working on it as people come up with additional ideas for its use. Sumner
