Resize a STL File For Me

[MarkF]

Just finished assembling my rooftop air conditioner and thought I would share some new creations:

  end-of-track buffer +++ air conditioner +++ 6 yard trash dumpster +++ 4 yard trash dumpster

[bostonman]

Those look great. Seems this is a serious hobby for you.

I printed the PCB box you "fixed" (more like made). First I printed mine that you fixed and it was horrible. When I do a 3D model, for some reason in my mind 0.25" seems tiny. As it printed I realized the dimensions were horrible. Also, I stopped the print because it began printing the top layers before the walls, but it left half as infill and the other half as solid.

The one you provided was excellent, however, my printer is in need of calibration because I checked the PCB with micrometers and it was just under 2" x 3" (update: I made the PCB 2x3 but wanted to confirm it wasn't made larger) but the PCB didn't fit. I had to make the model slightly larger and then the PCB fit.

[MarkF]

I have to check my printer again.
If I remember correctly,  the outside measurements (i.e. outside of a cube) are a few thou different from an inside measurement of a shell/pocket/opening.

When you do your calibration, try to pick a distance that covers most of the bed.  The larger the distance you measure for the calibration the smaller the error you will get.

[MarkF]

I forgot to mention that if you size the holes just right for the PCB mount, you can use a #4 machine screw without a nut to hold it in.  You will eventually wear out the plastic if you remove them a lot.  I have also used small #4 wood screws directly into the PLA.

[MarkF]

Those look great. Seems this is a serious hobby for you.

FreeCAD and I spend a lot of quality time together.   

It's just that the model railroad hobby is very expensive.
That 'railroad crossing' sign I showed a few posts back costs $6.00 while I can print it for pennies.
All these things for the railroad are so small.  I'll end up with a resin printer if I'm not careful. 
When I first started the hobby in the 80s, I could get Atherean 'Blue Box' boxcar kits for $5.00 each.  Last month I picked up a box car for $22.  And the prices just go up from there.  Non-DCC locomotives were $25 and now most start at $150.  A locomotive with DCC and sound start at $300 for most.

I need to get some people, cars and trucks but you easy pay $10 or more for a plastic truck or a half dozen people.
(Those cars and trucks in my photos are Mattel toys from when I was a kid and are a little too big for HO scale.)

Here's a new photo of those models for the layout that I posted over in the 'Model Trains' thread.
Plus lots of photos of other things I've printed.  Also, I made shorter walls for the office building.

[bostonman]

It's great you are able to connect to your hobby by making many pieces. It's probably nice to buy the pieces, but much better when you make your own.

Most likely I'll use a nut to hold the PCB box. Technically, if not for having a 3D printer and 3D layout "skills" (skills = attempt a design, mess it up, come on here, and have someone create a much nicer piece), I would have just stuck it in a hobby box or screwed it using standoffs.

As the silk screen on the PCB states, this is for a frequency counter. Long story short, I attempted to use this counter some time ago, noticed segments weren't lighting on the VFD, built a daughter board to incorporate a replacement IC (see attached photo), and now want to add an external display should the VFD fail in the future.

The PCB takes the display signals, puts them through a buffer, sends it externally, and then a receiving buffer will send them to an Arduino.

I wasn't sure if laying out two boards would be cheaper than one large, but, since size wasn't an issue, I put both circuits on one board and populated only the necessary components.

This project began over nothing more than opening the unit to see if the missing segments was due to a bad connection. Before long, it took over all my projects and it's been disassembled for nearly a year.

As for calibrating my printer, every time I think about calibrating it comes the need to use it and/or I'm caught up with other projects.

It's never been calibrated, so a learning curve may exist. Usually being off by 1/16 or 1/8th of an inch doesn't affect my prints, but I'd save time and material if a 2" x 3" PCB box really printed the correct size. As probably mentioned, prior to hearing about calibrating the printer, I thought incorrect print dimensions was just due to the low quality printer. It will be great to get much more accurate sized prints though going forward.

[bostonman]

After making some size tweaks, I printed the saw leg. It fits perfect but I plan to increase the base thickness a bit and reprint.

[MarkF]

Good
It will be interesting if the legs cut through the filament.

Hence, I suppose the reason for "I plan to increase the base thickness a bit"

[bostonman]

Attached is revision C which is size edits from the original (Rev A), thinner slot opening for the L frame (Rev B), and now Revision C which has a thicker base.

I managed to follow along just enough to make the size changes, but still impressed you were able to pad it at an angle. When I made some size changes, it seemed the triangle base wasn't moving with the padded angled part. I had to move it manually, size it differently, and basically did a trial and error approach until it "just looked good".

Also, you padded the base symmetric to the plane at 0.08". I increased it to 0.12", but removed the symmetric to plane along with reversing the pad.

As you can see from the attachments earlier, it came out looking identical to the original, so you did a fantastic job.

Making the base thicker was concern that sliding the base on hard surfaces will cause the PLA to wear out. I plan to print the first four layers solid along with 80% infill. Most likely I'll add some hot glue to keep the foot on the L frame, but it was quite tight; I actually had to tap it with a hammer to slide it off.

[MarkF]

You're not slacking on me are you @Bostonman?       
I occasionally run across some of your other projects on the forum but no CAD work.
What has happen to your priorities?

Thought I'd point you to some of my latest work on the railroad:
  https://www.eevblog.com/forum/chat/model-trains/msg5892116/#msg5892116

Showing off again.   

[bostonman]

You're a riot and much appreciated that you reached out; even in a comical fashion.

I'll start off by saying: over the last few weeks the thought of not tinkering with FreeCAD has come to mind and wondered if anyone thought I was going cold; or some fly-by-night user who vanishes. With the help users provide on here (and Lemon64 too), not just to me, but to everyone, I have a great level of appreciation along with making sure I express it. The last thing I'd want to do is give such a negative impression.

With the exception of some minor models that I made and not needing much else, I haven't tinkered with FreeCAD as a result. An internal level of guilt has existed because I think 3D modeling is so cool, and, each day/week I don't tinker with it is experience I don't gain.

Unfortunately my projects linger not necessarily due to losing interest, but needing a part or something that when ordered, takes a week or two to arrive.  Right now I have a few projects going on including a dismantled snow blower that is happy occupying just enough space so I can park, but causes me to walk sideways. Most often than not I think a project will be quick and easy. Turns out they go down a rabbit hole with lingering affects.

I should continue tinkering with FreeCAD again. One issue as I've mentioned is my lack of creativeness. If I don't have a need for a part, I lack the ability to just create out of the blue. Ever see those people who doodle while on the phone and they manage to create some cartoon character out of thing air? That's not me. The only doodling I do is drawing triangles. When I do have a need for a design, my mind is too 2D oriented and often times it keeps me stuck inside the mental box. Obviously I do think 3D, but, even when I draw something to explain, it's 2D with a front view, side view, and top view; seldom 3D. It's something I get mad at myself for because I just lack that drawing skill.

Reaching out is greatly appreciated. You're correct, I've posted a few times about different topics, so you at least know I'm alive.

Your models look fantastic and I actually thought about you about a week or two ago. I overheard someone talking while out, I don't know the conversation, but, from what I heard, it sounded like model trains. One guy said how do you get all the pieces, and the guy answered: you can download the software and 3D print them as others do. Then the other guy said I've seen very large trains.

For a moment I thought of the irony of it being you.

[CatalinaWOW]

A few comments.   One of the great benefits of a 3D printer is NOT waiting a few days or weeks for parts to arrive.  Rabbit holes are everyone's enemy.  You do seem to have a particularly severe case.  Awareness is the first step to control.

I also have a serious weakness in drawing.  One thing that has aided me in developing a little capability is practice on a quadrille pad.  Start simple.  A Neckers cube.  Use only 45 degree angles and the ruled lines.  The paper eliminates gross drafting errors which is half the problem for me.  Once that is under your belt expand to a cube made of square stock, one square across.  The first time will be slow but it will get quickly easier.

[bostonman]

One of the great benefits of a 3D printer is NOT waiting a few days or weeks for parts to arrive.

I fully agree. Waiting is one major factor, the other is just being able to recreate parts. Some parts don't exist or are so scarce that the price is expensive. That knob you made for my oscilloscope is one example. Periodically I look at the oscilloscope and wonder what would be in place of the knob if not for printing one.

Rabbit holes are everyone's enemy.  You do seem to have a particularly severe case.  Awareness is the first step to control.

My mind does wonder often. It's brutal when I'm trying to create/design something (usually mechanical) because I design it one way but realize it can be simplified, then think about doing it another way, etc...

Unfortunately I've always been better at dismantling, learning how the thing works, fixing, and reassembling. The creative part has always lacked which is why I don't make a great EE. Jobs I've had revolve around employees reading several dozen pages of a PDF, banging out something, and moving on. With me, I need to physically hold the object, play with the moving parts, etc...

The rabbit holes aren't always necessarily my fault. Sometimes I attempt to repair something I think is a quick fix, it ends up needing a part, local stores don't have the part, etc...

As for drawing. My handwriting/printing has always been atrocious. At some point I resorted to printing (now I can't go back to cursive) and then randomly changed how I printed words using capital letters and lowercase randomly. After years of doing it and being called out by my PhD friend, I practiced and now I don't do it. I think this is what contributes to poor drawing skills, but maybe I'm wrong. I can draw better if I'm copying something, but notice my space estimates are always off. By the time I'm halfway done drawing a line, I realize I'm 80% from the edge of the paper. Then I look at friends who struggle to figure out the correct way to hold a wrench, or think a hammer makes a good screwdriver.

What I've learned is: while we try to learn new skills, it's not always a bad thing to be bad at something because it just means we are better at something else.

[MarkF]

I'm fortunate in that I've always been able to visualize and rotate parts in my head. 
I can easily see the part from different angles.

My downfall is with creativity and in the artistic areas.  I don't just sit down a draw up imaginary parts in CAD.  All the CAD drawings are some part or object I need at the time.  Many different parts for the railroad to replacement parts or functional parts around the house.  Things like broken plastic parts in my mini-blinds on the windows and tool holder on my desk and varies mounting brackets and project boxes.

My latest nemesis are doors for these little buildings I'm doing.  Trying to have openings for glass in them with raised panels on the lower half of the door has been a real challenge.  Not the drawing part mind you, but the drawing it so it can be 3D printed.  You either break the door into a lot of small parts to glue together or add a bunch of ugly supports to try and remove.  One would think a door would be a simple thing to do.  Oh, and packing it all into a part 1/2" wide and 1" tall.

There's something for you to practice on @Bostonman.  Go measure up your front door, divide everything by 87 (HO scale 1:87), draw the door frame, the door itself, the raised panels, and the glass windows.  Any little window divider lights tend to need to be exaggerated because it's not possible to print the small muntins.