I use the crank pin method regardless - MUCH smaller hole than the oen needed for a Tortoise style back and forth action. Also works with ANY thickness subroadbed and roadbed without needing progressively thicker music wire. Works for any sort of machine, Switchmaster, Tortoise, or servos. Can even lay a Tortoise on its side so it doesn;t stick down so far using a linkage like this.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Carl,
There were/are several knock off Switchmasters and brands with similar sounding names (switch tender) that do draw lots more current than the genuine Switchmaster motors. For a while the Swithcmaster brand was not in business (I don't know all the details - see the BIS site for info on this) There were some other companies that filled the void. The brand is now back in bizz at the Builders in scale site (for many years now), with motors running the spec.s you cited. I think that that because of the confusion over the names and because the various other brands do draw large amounts of current, your manufacturer decided it was easier to say the product won't work with switchmaster.
These motors have their fans and detractors. I live in switchmaster country. I have 70+ on my layout and most of the modelers I know use them. We like the ease of mounting and the quietness along with the low stall current. Most installations I know of have operated reliably for over 20 years. Biggest drawback is the appearance of the crank pin if you use that type of installation and the lack of contacts. There are various wiring schemes that are easy and do solve the contact issue.
Your mileage may vary,
Guy
see stuff at: the Willoughby Line Site
Yeah, not so sure they were mil-surp, they are Hankscraft display motors packaged with the hole drilled int he chaft and some other parts to make them into switch machines.
However, at one time there was a LOT of mil-surp advertised for model rialroad use. Check late 40's/early 50's issues of MR. That's where so many modelrs got those rotary relays they used for switch machines - military surplus. Tons of other standard relays came from leftover military inventories. Remember, we kept on producing right up til the end of the war, then suddenly there's no one left to fight, no equipment blown up or shot down needing to be repalced, yet the factories had tremendous inventories of parts. I recall one add selling a motor-generator set, that produced 24V DC (for aircraft starters) and they were just saying basically run the AC motor at lower RPM and get 12V out of it. Toggle switches, panel lights, all sorts of goodies were advertised well into the 50's.
I have a few of those and have used them with no problems. The only draw-back that I can see is that they don't have the aux contacts that the Tortoise does. But if you need contacts, it is not that hard to add a microswitch to the installation.
One thing that I had to do though, was provide a positive stop to the arm from the motor, in both directions. I used a couple of long screws into the subroadbed to stop the length of throw on the motor arm. Otherwise they wanted to push on the switch points too hard.
Elmer.
The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.
(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.
Here's what I've got.
The end where the shaft comes out has "HANKSCRAFT MOTORS" stamped into the plastic.
I have the right to remain silent. By posting here I have given up that right and accept that anything I say can and will be used as evidence to critique me.
carl425 How sure of this little tidbit are you?
How sure of this little tidbit are you?
The sellers even stated in their advertsements that the motors were USAF military surplus servo control motors, and were built to stringent military specifications for durability and reliability. I seem to recall that they were priced at around $10 each at the time, which was less than a Tortoise.
Knowing how military procurement works, USAF may have paid over $100 each for them.
I believe one company called them "Switch Master" and the other "Torque Master," and they came in a plain white cardboard box with a NSN stamped on one end.
I have since seen them advertised under different names, so more than one or two people have been able to source these motors in bulk. In later years, one seller even mentioned a manufacturer (Honeywell?) that was his apparent source.
cacolethey were apparently purchased as military surplus items
How sure of this little tidbit are you? I can't imagine what use the guys that buy $7,600 coffee makers would have for these.
mlehman You don't recall the names of these companies do you?
You don't recall the names of these companies do you?
Mike,
No, I don't recall the company names, but one had an Urbana address and the other a Champaign address -- and I know Champaign/Urbana are practically indistinguishable from each other. (I lived in Urbana way back in 1964-5).
cacoleThe Switchmaster motors were initially being sold by two companies just outside Chanute Air Force Base in Illinois, because they were apparently purchased as military surplus items.
cacole,
Hmm, that's a part of local history I didn't know. I'll have to keep my eyes open for other references. You don't recall the names of these companies do you?
Mike Lehman
Urbana, IL
We have 3 or 4 Switchmaster motors on our HO scale club layout that have been in use for 20 years or more. One has had to be replaced over the years due to the brass tube they use getting twisted off because the wrong value resistor was used. It was replaced with a Tortoise.
The Switchmaster motors were initially being sold by two companies just outside Chanute Air Force Base in Illinois, because they were apparently purchased as military surplus items.
The resistor provided with them at the time of purchase was not the correct value for our use, so a lot of experimentation was necessary to get the correct value, especially when two needed to be wired in parallel to throw two turnouts for a crossover.
rrinker Yes, it's the current draw WITHOUT the resistor that is too high. The fact that you MUST use the resistor or the gears will strip tells me all I need to know about these motors - that is, they aren't intended to be stalled like they are used for model railroad puposes. That and the mounting is more complex. With the resistor they should be fine to run with any sort of circuit designed for the Tortoise. What's the run current, before it stalls? It SHOULD be less than the stall current. --Randy
Yes, it's the current draw WITHOUT the resistor that is too high. The fact that you MUST use the resistor or the gears will strip tells me all I need to know about these motors - that is, they aren't intended to be stalled like they are used for model railroad puposes. That and the mounting is more complex.
With the resistor they should be fine to run with any sort of circuit designed for the Tortoise. What's the run current, before it stalls? It SHOULD be less than the stall current.
Run current is 4-5ma. As for mounting, I don't find them that much more difficult than the Tortoise. I think when they were introduced they had a mounting advantage since the bendy wire that moves the points is the same as what many users already had in place for the twin coils. Of course, that was then...
My understanding is that the original purpose for these motors was for animated displays. They were made to stall without creating problems. They are also 3-volt motors intended to run on the two D-cells that were the standard for these displays so it's not surprising that 12 volts would strip the gears. What would happen to the Tortoise if you applied 4X it's rated voltage to it?
I think the biggest advantage of the Tortoise is that it will hold the points closed after current is removed. The Switchmasters will relax and open up.
Don't get me wrong, I prefer the Tortoise. It's just hard to ignore the $200 that it would take to buy 13 of them to replace the "free" Switchmasters.
I noticed in another thread folks talking about the power supplies for switch motors and lighting and realized I needed to do the same planning. Tortoise current requirements are fairly well documented at around 15ma @ 12v. I have a bunch of them ready to be installed on the layout, but I also have 13 never used Switchmasters that could be the source of some savings if I can use them.
So I decided to measure the current draw of the switchmasters. When hooked it up using the resistor that is supplied with them, I measured 9.4ma @ 12v. I found this surprising as I have been told by driver board manufacturers that the Switchmaster draws too much current for their board and I had to use the Tortoise (I measured 17.2ma which was in line with the "about 15" that I've heard).
Am I missing something? Are the manufacturers afraid of the Switchmaster because they think I might use them without the resistor? I didn't measure that way because the documentation says 12v without the resistor can strip the gears.