RMweb Gold tomparryharry Posted March 24, 2014 RMweb Gold Share Posted March 24, 2014 Hi Folks, I'm using some H&M point motors on my extended shunting plank, but I think there is a 'challenge'. The throw on the solenoid arm is greater than the closure distance of a Peco code 75 point. I think I can overcome this, by introducing an 'Omega' loop into the operating rod, to take up the excess travel. I'm fairly sure I'm not the first person to have this challenge, so I'm really looking to garner any previous experience out there. All responses, etc, gratefully received. Many thanks, Ian Link to post Share on other sites More sharing options...
66C Posted March 24, 2014 Share Posted March 24, 2014 Hi Ian How are you planning to mount and link the H&M to the turnout? If you are using the original crank that was supplied with H&M solenoids, you can use a hole closer to the pivot rod to reduce the throw. If you are mounting the H&M under the baseboard, make up a crank from a piece of rod with a length of brass wire set into the top. The idea is to set the rod into a hole through the baseboard and turn down the end of the wire to engage with the hole in the turnout tie bar. The length of the brass wire will determine the travel and should take up any excess. Easier to suggest a solution if you give some more information about mounting. Regards. Link to post Share on other sites More sharing options...
RMweb Gold tomparryharry Posted March 24, 2014 Author RMweb Gold Share Posted March 24, 2014 Hi, thanks for the reply. The point motor is definitely under the board, which is 4mm ply. I'd thought about mounting the motor upside down, and fixing thro' the ply, with countersunk set screws, most likely brass. I think I see where you're going. Make a smaller crank, and smaller throw...... Ian Link to post Share on other sites More sharing options...
RMweb Gold unravelled Posted March 24, 2014 RMweb Gold Share Posted March 24, 2014 Didn't the H+M point motors come with an extension for under board mounting? The lever pivot was drilled and had a set screw to allow for varying baseboard thicknesses. All the lever arms have a choice of throw to cater for various gauges. Dave Link to post Share on other sites More sharing options...
66C Posted March 24, 2014 Share Posted March 24, 2014 Hi again Here is another option for the linkage: The motor shown is a Fulgurex - the H&M will work just as well. An auxiliary crank (a servo horn) is used with a wire rising through an operating slot in the baseboard. The operating slot is immediately underneath the tie bar. This method has several advantages over a direct crank from the point motor: Installation is easier as the motor is separate from the crank. The various locating holes in the H&M crank and the servo horn give plenty of adjustment in the throw. Final adjustment can be made after installation by adjusting the omega loop. The omega loop absorbs some of the operating shock of the solenoid so less stress on the tie bar. Regards. Link to post Share on other sites More sharing options...
Theakerr Posted March 24, 2014 Share Posted March 24, 2014 First, I would question using H & M solenoid motors with code 75. I am not at all sure that the code 75 points are robust enough to handle the shock loads although i am open to the facts if they are different. Having said that, yes the throw total distance on the solenoid is greater than the throw on the point tie rod, but the same holds true for code 100 points using peco or H & M solenoids. Basically the electromagnetic pull is such that the moving insert goes as far as it can go then stops. Since the operation of a solenoid point motor is pulse then once the pulse is removed there is no load. Link to post Share on other sites More sharing options...
RMweb Gold tomparryharry Posted March 24, 2014 Author RMweb Gold Share Posted March 24, 2014 First, I would question using H & M solenoid motors with code 75. I am not at all sure that the code 75 points are robust enough to handle the shock loads although i am open to the facts if they are different. Having said that, yes the throw total distance on the solenoid is greater than the throw on the point tie rod, but the same holds true for code 100 points using peco or H & M solenoids. Basically the electromagnetic pull is such that the moving insert goes as far as it can go then stops. Since the operation of a solenoid point motor is pulse then once the pulse is removed there is no load. Hi, thanks for the reply. I take on board the load is quite powerful, as well as the solenoid throw being outside of the scope of the switch rails. My wanting to use H&M motors is simple; I've got some here. I could buy some more Tortoises or Cobalts, but that is outside of the latitude I have set, which is to use what I have to hand. Bill's solution seems a neat idea, in using a servo horn to limit the throw of the H&M motor. Even better, is that I've got some spare servo horns knocking about here. Damned if I can find them, though! Thanks, Ian Link to post Share on other sites More sharing options...
Pacific231G Posted March 24, 2014 Share Posted March 24, 2014 Hi again Here is another option for the linkage: Fulgurex with servo horn.jpg The motor shown is a Fulgurex - the H&M will work just as well. An auxiliary crank (a servo horn) is used with a wire rising through an operating slot in the baseboard. The operating slot is immediately underneath the tie bar. This method has several advantages over a direct crank from the point motor: Installation is easier as the motor is separate from the crank. The various locating holes in the H&M crank and the servo horn give plenty of adjustment in the throw. Final adjustment can be made after installation by adjusting the omega loop. The omega loop absorbs some of the operating shock of the solenoid so less stress on the tie bar. Regards. I wish I'd seen this before I fitted my H0m layout with Fulgurex motors using the mechanically awful method they suggest !! A very useful idea. Thanks Bill. Link to post Share on other sites More sharing options...
66C Posted March 25, 2014 Share Posted March 25, 2014 First, I would question using H & M solenoid motors with code 75. I am not at all sure that the code 75 points are robust enough to handle the shock loads although i am open to the facts if they are different. Having said that, yes the throw total distance on the solenoid is greater than the throw on the point tie rod, but the same holds true for code 100 points using peco or H & M solenoids. Basically the electromagnetic pull is such that the moving insert goes as far as it can go then stops. Since the operation of a solenoid point motor is pulse then once the pulse is removed there is no load. I have used H&M solenoids with Peco code 75 - no problems, nothing came apart. They (H&M) tend to be much more of a liability with hand built turnouts that use a copperclad sleeper as a tie bar - been there as well! Regards. Link to post Share on other sites More sharing options...
Theakerr Posted March 25, 2014 Share Posted March 25, 2014 Interesting thread in that i have a friend who is in the process of building a layout and I suspect some of the points (no pun intened) brought up here will be of interest to him, especially that solenoid points are OK with code 75. The servo horn is a very interesting idea, especially on the basis that it could be used through thicker section baseboards. I have used a sort of derivative in a couple of specific locations using model aircraft/car cranks. Link to post Share on other sites More sharing options...
RMweb Gold unravelled Posted March 25, 2014 RMweb Gold Share Posted March 25, 2014 An even simpler method of reducing the throw is to mount the motor, and so the crank, at an angle to the tiebar. A little experimentation should give a suitable angle. The push/pull won't be quite in line with the tiebar, but that shouldn't be a problem. Dave Link to post Share on other sites More sharing options...
RMweb Gold tomparryharry Posted March 25, 2014 Author RMweb Gold Share Posted March 25, 2014 Thanks for all the thoughts on here. It would seem that the throw on the smallest H&M crank position is around 3.2mm (1/8" in old money) whereas the throw on the point is around 2.4mm. It would seem that I've got to lose around 0.8mm, or 30-ish thou". I'll leave in the fulcrum spring on the tiebar, to take up any slack, as the blades go over. I've managed to dig out the servo horns (hurrah!), so some experimentation is in order. My photo skills are cr*p, but I'll try to post some in the near future. Many thanks, Ian Link to post Share on other sites More sharing options...
LindsayM Posted November 8, 2015 Share Posted November 8, 2015 Hi there, I agree with most of the previous comments plus a couple of observations, if the swich to terminals 4-5-6 isn't working, try squirting some WD40 or CRC on them, be careful as you don't want too much. However what I found was the bigest advantage with these point motors was in their construction, they cannot be forced from their last electrically operated setting, I had a few old Peco points (bought with my "paper boy" money from the mid 1950s, they had various sorts of damage and were missing their C-springs used for the "overcentering" function, ie. ensured the points would stay hard against the track rail when operated, Using these H&M motors that problem was resolved. The blades WILL stay where they are supposed to be. thanks for listening/reading (if you did) regards, Lindsay in NZ Link to post Share on other sites More sharing options...
hayfield Posted November 8, 2015 Share Posted November 8, 2015 The one thing about the omega wire, or if using straight under the point using a sprung wire is that both these methods act as dampers to the through action Secondly by using cams you can adjust the throw One other thought is to keep the point motors at the sides of the boards with wires/rods going to the points to ease with maintenance of the motors Link to post Share on other sites More sharing options...
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