Today I have mostly been printing...

O thouse are very very nice,, did you design them your self?
 
A question for you tech types wot know, I am trying to design something on tinkered where I need a 10mm square solid section to plug into a square hole, can somebody tell me what the clearance should be as i guess a 10mm bar will not slot into a 10mm hole? It needs to be a fairly tight fit and probably be glued in place, when assembled.
Thanks
Dave
 
Thanks Mike!
Sadly I can't claim credit for these. They're much too well designed! :D They're both remixes I found elsewhere.

The harp stand I found on Thingiverse but I'm redesigning the indicator board for it. It's nice and 'un-chunky' for want of a better word :)
The LGB-style one I discovered on TinkerCAD. That will need altering too I think, since the mounting arms seem incredibly long. It's nicely detailed though.

One thing that I find annoying about Tinkercad is that importing an STL results in a single object, which makes modification really difficult and messy. It's a shame it can't try to analyse and segment the component shapes :(
 
Hi Dave. My 2c worth from playing about:

I'd firstly print off at the measured size if a tight fit is needed. The filament always shrinks a bit when printing, so you're likely to end up with 9.something mm for a 10mm measurement.
If it ends up under/oversize I just guess, judging it by eye and getting closer and closer.

For example, I've just made some bushes for the riving knife on my table saw. I needed a tight fit and ended up going a mm oversize for the bush in the design, then filing it down ever so slightly to be able to tap it in snugly to the hole.

Sorry for not offering a more scientific explanantion. I'm sure others will have one! :D
 
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Tanker man said:
A question for you tech types wot know, I am trying to design something on tinkered where I need a 10mm square solid section to plug into a square hole, can somebody tell me what the clearance should be as i guess a 10mm bar will not slot into a 10mm hole? It needs to be a fairly tight fit and probably be glued in place, when assembled.
Thanks
Dave
Click to expand...
Not quite a simple question, there are three type of mechanical "fits":

  1. Interference fit, where the plug at its smallest tolerance is larger than the hole's largest tolerance - (will not slide in)
  2. Clearance fit, where the plug at its largest tolerance is smaller than the hole's smallest tolerance - (will always side in)
  3. Transition fit, this is where the plug may or may not fit the hole as the tolerances overlap - (might be tight, might not)
So if you want something to fit, depends how you want the fit, fit and defiantly not move, fit and slide, or a snug fit.
 
I've been looking and it would be very simple to have either of the switch stands fit the parallel pneumatic housings.

The harp stand would obviously look a bit incongruous alongside it but I think its my favourite of the two so I'm going to make either of them fit. It should just be a small modification to the pneumatic switch throw arm file and to the housing itself.

I'll then remix the two stands to incorporate a fixing plate that suits the housing. Either can then be attached via the baseplate and connected to the end of the throw arm with piano wire/ straightened paperclip/brass wire or whatever :)
 
The parallel actuator housings themselves have a choice of throw arms, so that the points can either be straight or switched with the actuator at rest.
That choice of throw arm is important if the switch stands are added, in order to have the indicator move in the direction of the rail.

Here's some video of the two different switch stands in operation, slaved off the pneumatic actuators;
Harp style stand in operation
Circle style switch stand in operation
 
A couple of downloads from ‘thingiverse’ they are to go on a RC model boat that I am helping my nephew, to build. To large for ‘G’ scale but I’m sure I can resize and use . The man is a crane driver and is printed with a hard hat, ( his hat is made of ‘green stuff’ for the boat) , hence the ‘Max By grave’ hands but I think he would make a good driver for a dismal. ......................the young lady took some painting..........couldn’t keep my hands still!!!
the LGB figure is for size comparison.
Dave
011E03BD-0EC3-4918-9908-7F4450EB9AE4.jpeg
 
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