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O scale (1:48) c.1930 Hydrant

Test Print 1

I modified the design for these hydrants that I originally created to print at Shapeways by removing the hollow interior. With that done I brought the STL file into CHITUBOX to add the supports. There I went with light supports .. possibly (probably) a mistake.

I exported the supported STL from CHITUBOX and then opened it up in PrusaSlicer 2.2.0. I made 10 copies at which point Prusa Slicer refused to add any more to the build plate.

I tried to get smarter than the slicer and manually arranged extra pieces. This was a major fail along the outside edge. They printed partially and/or greatly deformed like candles melting. I suppose the PrusaSlicer knew what it was doing
Then, these all failed by coming off of the supports. That most likely/probably is using too light supports.

Prints

Here’s what I ended up with. The part that shows .. sticks out of the ground came out fine.

Conclusion

Two things …

  • First .. accept the way that the slicer wants to arrange the parts
  • Second .. make the supports larger. I went to CHITUBOX for placement of the supports with the idea that it does a better job than PrusaSlicer. Well .. it makes MORE supports and you have greater control of the position and placement. PrusaSlicer wants to use less but larger supports. I can’t go with AutoSupports as it is determined to put a support on every bolt head. So the next step is to run AutoSupports .. look at where the slicer wants to place them and then add supports manually in approximately the same location while avoiding the bolt heads.
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Not So Fast “Hot Rod”

I’ve started to put some of my test prints up for sale and was happily doing so with O scale transformers when I broke the mounting bracket off of one. I sat for a second ‘observing’ and did some checking .. and I had the walls too thin. This was designed a good while ago and I had less experience with what works and what doesn’t. In this case the walls were about 0.35 m .. much too thin. Darn.

You can see the ‘bracket’ .. the idea is that the 0.51 mm hole (~0.20″) takes a small piece of 0.020″ wire long enough that it sticks out a bit .. enough that you can drill a matching hole in your telephone/power pole to mount the transformer (matching ‘bracket’ at the bottom).

While I was checking this out .. I realized that the walls of the model were also too thin at around 0.4 mm .. again by excuse is that this was earlier in my design ‘life’.

This means the ten (10) varying O scale transformers I was ready to put up in the store will instead either go in the trash or a junk pile on the layout.

The “new and improved” Version … Ver3 now has 0.7 mm walls both for the canister and the hole passing through the ‘bracket’ which is larger of course.

If you note that strange look of the transformer .. that is because it is a c.1920 transformer .. ribbed sides for cooling, bolted lid, filler plug up on top center and a drain plug near the base.

There’s the old saying .. “Don’t count your chickens before they hatch” .. it seems to be applicable for 3D printing too.

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MMR (Mild Morning Rant)

An MMR (my definition) is not REALLY a rant as such but as the title indicates more of an .. call it .. irritated observation.

I am a creator of miniatures for hobbies .. Model Railroading, Military etc. .. using CAD to make 3D models. Doing that .. I sometimes have to examine said model very, very closely. Now .. one would think that the answer to that is simple .. using a magnifying glass or an OptiVISOR and yes ..I have both. The problem with the magnifying glass is that while it works fine for close examination of the model I am constrained since I have to hold in my hand. Oh .. says the gentle reader .. use the OptiVISOR then .. that completely frees the hands. My answer is .. yes . .it does .. but I don’t WANT to use it .. it is bulky and gets in my way.

My preferred tool is what is called an Monocle Loup .. evidently considered “Old Style” .. it is held in the eye socket like .. well .. a monocle.

I have some. They work GREAT .. almost ..

I simply CAN NOT lock one in my eye socket. I *think* they are simply too big diameter.

So what’s the “Rant” part of this MMR?

For all the magic and wonder of the internet and Google and it’s little Commie brother Bing ..  I simply can not find the information I want which is .. can you purchase a monocle loup by the dia of the part that fits the eye socket? I know that sometimes the “trick” with a search engine is to put in the correct terms .. but there are times I am stumped.

Well .. perhaps not stumped .. but paused like an old cassette recorder ..

Did find where they are also called “Eye Cup Loupe”

… time to explore THOSE three words .. but more coffee needed

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Just Because you CAN doesn’t mean you SHOULD!

Long, long ago back in the days that the sun always would be shining and walking some place was always downhill … I had some O scale beer/soda bottles printed at Shapeways. This was in the Haycyon Days when having something printed at Shapeways did not require taking out a bank loan.

Recently Larry Knapp asked me if I still had these for sale. My quick answer was that while you could probably still have Shapeways print them they are darn expensive ($7.50 for 24 bottles for example)

So .. I printed off some .. tried for 100 .. perhaps 90 printed. What a pain. I spent an hour at least before I got the small amount I ended up with .. which is .. a bunch of little bottles with a little ‘tail’ from the supports … and it came to me that this is NOT the way to go with this. The bottles need to be on a small sprue that would allow you to paint them before cutting them off said sprue.

So many things to do .. so little time.

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Jersey Barrier

With some prompting from a customer – Anthony Perillo – I created some O scale (1:48) Jersey Barriers – a 10′(3m) and a 20′ (6m) version. According to Wikipedia ..

Jersey barrier, or Jersey wall, is a modular concrete or plastic barrier employed to separate lanes of traffic. It is designed to minimize vehicle damage in cases of incidental contact while still preventing vehicle crossovers resulting in a likely head-on collision.

I was pretty happy with how well they printed

I also printed both the 10′ and 20′ models in HO scale and was quite surprised at how well they came out even using a .4mm nozzle. I am sorely tempted to switch over to the .25mm nozzle and print a bunch in HO as stock.