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Regular poster 226 posts tommypelley Regular poster 226 posts
tommypelley

for those who may be looking I have designed a servo mount for turnout control. im using a 9g servo, levered micro switch with 11mm hole spacing, and .9mm wire to throw the turnout.

its listed on thingiverse as srvo mount for model train turnout. you can also find it listed as servo mount 3B

the direct link is  http://www.thingiverse.com/thing:3603598. 

the switch I'm using has the number  l4 5a 250vac. I'm using this switch because its what I had a bunch of laying around. this could easily be adjusted for other switches. if you would like to adjust for other switches PM me and ill send you a download of my tinkercad file so you can do that.

the servo I'm using is a miuzei sg90 9g micro servo. so again if you have a different servo you'd like to use PM me and send you tinkercad download of the file so you can adjust to fit your servo

as mentioned in one of the comments the pivot may experience excessive wear over time and as per this advice I now plan on drilling the pivot holes in mine and inserting a section of brass tube. I would edit the design to accommodate this but since no two people use exactly the same material I think drilling for the tube is a better choice

I designed this using material I had on hand to experiment with using servos for turnout control. feel free to use as is or to modify for your parts.

my test pieces I printed on my prusa i3 clone using a generic PLA with 15% infill and a speed of 45mm/s. my pieces for installing are printed using most of the same parameters with the exception of changing the infill to 30% 
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Neil Erickson NeilEr Moderator 5,773 posts
Neil Erickson NeilEr

Nicely done!

Are you printing these yourself?

Another modeler willed me a number of Tortoise motors so it may be a while before I run out. A nice benefit of these is the power routing. Could your mount be modified to add a mico-switch to power the frog or facia light?

Neil Erickson, Hawai’i 

My Blogs
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trainman6446 Frequent poster 667 posts
trainman6446

Nice mount. Just downloaded

Nice mount. Just downloaded and sliced with Cura. Ill print it when I have some time. 

Tim S. in Iowa
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Jim at BSME Prolific poster 2,084 posts
Jim at BSME

re: Micro Switch

@Neil, it already has a place for two micro switches, while the picture here doesn't show it, the description does:

Quote:
levered micro switch with 11mm hole spacing

And since this is on thingiverse it would be for a home 3d printer, although I guess you can upload to shapeways for printing. If you go to thingiverse there are a few servo mounts:  https://www.thingiverse.com/search?q=servo+mount+for+model+railroad&dwh=755ccc8d1cefb5f 

The neat thing about this mount is it has the same footprint mount to the layout as a tortoise, so might be a direct replacement.
- Jim B.
Baltimore Society of Model Engineers, Estd. 1932
O & HO Scale model railroading
Check out BSME on: Facebook, Instagram
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pierre52 MRH Author 1,489 posts
pierre52

Hole may wear out

That is a nice design and a nice print.  However, could I suggest a minor modification.  The hole that the actuating wire pivots in is subject to quite a bit of force and requires a moderately  good fit. I typically use 0.7mm piano wire in a 1mm diameter hole through an aluminum base plate.

  PLA/ABS/Petg or whatever else you print this with will, I suspect, wear quite quickly.  As the hole wears and increases in diameter the servo will require more and more throw to activate the turnout.

A simple mod would be to enlarge the hole in the holder to accept a short length of appropriately sized brass or aluminum tube glued in with CA.  Hole enlargement should be at the design phase as if you drill the hole larger once the item is printed then you will likely be trying to glue to infill rather than solid wall.

You may also want to list the specs of the servo it was designed for as virtually every 9g servos that I know of has different dimensions.

Peter

The Redwood Sub
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Ron Ventura Notace Frequent poster 689 posts
Ron Ventura Notace

Could you post a link please?

I searched on Thingiverse, using a variety of combinations of servo, mount and 3b. For whatever reason I can’t find your model.so could you please post a direct link. Thanks.

Ron Ventura

Melbourne, Australia
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lnxlnx Regular poster 120 posts
lnxlnx

Link to mount

This looks like the servo mount  https://www.thingiverse.com/thing:3603598 and indeed the username on thingiverse is given as

Quote:

tommy pelley

so I would call that a match. 
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tommypelley Regular poster 226 posts
tommypelley

Yes. I print these on my

Yes. I print these on my prusa i3 clone
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tommypelley Regular poster 226 posts
tommypelley

Already has a power routing

Already has a power routing switch mounting place
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tommypelley Regular poster 226 posts
tommypelley

User name is tommy2tap just

User name is tommy2tap just like here. Try searching servo mount for model train or " srvo mount 3B". I probably need to update the name since i misspelled servo when i uploaded it
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tommypelley Regular poster 226 posts
tommypelley

http://www.thingiverse.com/thing:360

http://www.thingiverse.com/thing:3603598
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Ron Ventura Notace Frequent poster 689 posts
Ron Ventura Notace

@tommypelly Thanks

Thanks for this. I really like the design. I did have to make a small change though. Your servos may be different, but the slot for the cable was too low for the servos I am using. I took your stl into tinker aid and moved the slot up about 2.5mm. Reprinted it and the servo fits perfectly. I’m going to print a bunch of these to use on my layout. I’ve tried a number of mount designs, and this is by far my favourite. 

I read Peter’s warning about the hole wearing over time, and it will be interesting to see if that becomes a problem. If it does then it will be simple enough to print a new mount. If it becomes a real issue you could back the mount with a piece of sheet aluminium. If you wanted to get really fancy you could embed the aluminium into the print itself, but that’s probably a bit extreme.

Ron Ventura

Melbourne, Australia
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JeremyBrown New member 28 posts
JeremyBrown

Huge Thanks to Tommy Pelly for sharing!

Thank you for sharing this 3D design!  I have printed off a few and I am getting ready to install some.  I don't think the fulcrum hole will be an issue.  Look at Tortoise machines, they have the fulcrum hole and I know of some that have been in service for over 25yr with no problems.  Great design!

Jeremy Brown 

Santa Fe - High Desert Division

Layout Information and Updates:  https://www.facebook.com/groups/490745031104239/

 
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