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  • #46
    9" wheels, I thought my 3" wheels were big.Our town had a Hobo get to gather yesterday. Some one had a model live steam engine there running. Our local news paper don't tell you what is going on till the day after then wanders why nobody comes to the event. I missed it. I think the person was from out of town I would like to have talked to him.

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    • #47
      Originally posted by Bill Shields View Post
      if you are making wheels, remember that eventually you will need 8 more for the riding car...
      Yes, my ten-wheeler with tender plus four cars (three 2-axled, one 4-axled) - that was 38 wheels altogether...

      Edit: You can see a photo of the patterns here:

      http://www.sparetimelabs.com/animato.../460/460c.html
      Last edited by Jan-Eric Nystrom; 09-14-2014, 02:34 PM.
      Greetings,
      J-E

      There is a very fine line between "hobby" and "mental illness"...

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      • #48
        The wheels ans axles are finished. Now making the blanks for the gears.
        Attached Files

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        • #49
          Ed,
          Looking closely at the photos of your finished wheels, I can see a reflection of your grinning face.
          Nice work...accomplished in a short amount of time!
          Very much looking forward to watching your machining steps while making the gears.
          Tim
          (If anyone needs stock gears, I have a few sets that I would consider selling or trading.)

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          • #50
            Thanks Tim If my gear cutting does not turn out I"ll need a set of gears. Just a quick question. What size is the hole in the gear that goes on the engine and is it the same shape as the other gears?

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            • #51
              Ed,
              The gear on the engine crankshaft is a 1" dia - 20 tooth/20DP. - same as the gearbox top gear.
              The center hole of the gear will be drilled/reamed to match your crankshaft outer journal OD. Mine is 0.375" dia. It is held in place with two set screws thru the hub. There will also be four holes drilled on the end of the hub to mount the water pump drive.
              If you need more details, let us know. This should get you started. It would be best to hold off finishing this gear until your engine is further along.
              Tim

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              • #52
                Thanks Tin that help's a lot. I think I have a problem. I got the dia of the gears from Martin webb site they are
                Tooth wide dia.
                25 .375 1.375
                20 .575 .859
                24 .575 1.063
                30 .575 1.359

                You said your 20 tooth was 1.000 I measures the centers of the holes on the base plate and the radius of my gear blanks the gear blanks are too small. Could you give me the dia of the gears? It looks like I get to make a new gear blank set. Have a good day. Ed

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                • #53
                  Wrong diametral pitch?

                  See this:

                  https://en.wikipedia.org/wiki/Gear#Pitch_nomenclature
                  Greetings,
                  J-E

                  There is a very fine line between "hobby" and "mental illness"...

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                  • #54
                    Ed,
                    You are looking at the correct gear specs. It took a minute to see that the OD's you listed are for the hubs. Recheck the specs and refer to the overall gear Outside Dimension. Example, the 20 teeth crank gear and top crankcase gear (Martin #S2020) has a width of 0.575" and a hub OD of 0.859". The size of the gear OD is 1.100".
                    By the way, mine are 14-1/2 deg gears.
                    Tim

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                    • #55
                      Guys don't get old. I looked at my original notes and had the right size written down, when I copied the sizes to a work piece of paper I copied the hub size instead of the OD. It's a good thing I like making chips.Have a good day

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                      • #56
                        Ed,
                        Maybe look at it like this: you now have a jump-start on making a set of smaller gears you'll need someday?
                        Tim

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                        • #57
                          Also, depending on the grade of the track where you run, you may want to have an extra 'crank gear'...smaller gear for steeper grades or larger loads (more riders)

                          This is why (eventually) the engine frame will be mounted in slots in the bed so that it can be moved to accommodate the center to center distance.
                          Bill Shields
                          Living proof that just about anybody can build a working loco...

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                          • #58
                            Originally posted by Bill Shields View Post
                            Also, depending on the grade of the track where you run, you may want to have an extra 'crank gear'...smaller gear for steeper grades or larger loads (more riders)
                            Keep in mind, though, that there is a certain point of grade/load when changing the gear ratio won't carry any more passengers - it's the well-known problem of wheels slipping on the rails!

                            There are many formulas to calculate the max tractive effort vs. grade and engine weight, but none is precise, and the traction depends on rail/wheel materials, and weather, too!

                            Personally, my 0-6-0, weighing 120 kgs, can pull a 500 kg load up a 4% grade - so, four times the engine weight. Any more, and it will start to slip. On wet rails, maybe only half that.

                            Use that as a starting point for your own estimates.
                            Greetings,
                            J-E

                            There is a very fine line between "hobby" and "mental illness"...

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                            • #59
                              Tim if you still have a set of gears I need a set. Let me know what I need to do to pay. After finishing my gear blanks. I set up to cut the gears, my set up failed and I destroyed the gear blanks. At least I found out how to make the blanks and scrap. Have a good day. Ed

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                              • #60
                                Ed,
                                Sorry to hear the setup failed. I can relate...
                                I have a full set gears. New, in the sealed boxes. Purchased a couple of years ago. As a sanity check, I searched a couple of Martin suppliers for current pricing and saw that they have jumped up a little. I will send a set if you're OK covering my cost.
                                Are you set up to receive PM's through this forum?
                                Tim

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