Monday, June 6, 2016

Construction Vehicles, Road Roller, Road Grader, Payloader

The latest line up of HO scale construction vehicles I have built.  The road graders are metal toys that I updated and weathered a little.  The road rollers are and the small bucket loaders are mostly 3D printed on a home printer, an Afinia, and are based on prototypes.



Payloader, little bucket
I designed the these Payloaders based on a single photograph.  

They are a little small for printing at home, but with a little work, they are, in my opinion, acceptable, if you hide them a little.

I designed it without the hydraulic cylinders, but with a place to mount them.  Although, the parts are so small, they did not form well.

To avoid ridiculous amounts of support material, I exploded the drawing into a printable form.

I lot of little pieces to glue together, but not too hard.

I used brass tube and wire for the hydraulic cylinders.

Road Roller
I ran into a 1940's road roller at a gas station.  It was on its way to the scrap yard, so I am pretty sure these are the last pictures ever taken of this machine.  I also ran into a second old machine, the one pictured with the tires still in place, in my travels.

I designed most of this while showing my 3D printed items at the Worlds Greatest Hobby Show when it was here in Kansas City.  By the way, LOTS of young people at that show.  All the people that say the model Railroad Hobby is dying, were not at that show,

I generally draw the finished, assembled item I am planning on printing, then I decide how to explode it for optimal printing.  In this case, I felt the only acceptable way to make the rollers, was to use 7/16" brass tube, so I only printed the end plugs.

I started doing test prints at the show, and by the time I made all the adjustments, reprints, redesigns, etc., I had most of the parts for four road roller, so I gave one away, and built three.

The wheels, tires, and mounting system were all printed separately, for various reasons, but if nothing else, it made them easier to print.  The mount has a pin on it, and the wheels have a dent, to they would align.

As I assembled them, I tried different ideas on the rollers, as the printed center axle did not look too good.  In the end, I feel the best option was printing a hole, and then inserting a styrene axle.  They are NOT made to turn, they are just for looks, but the axle on the front wheel is out in the open.

I generally prime all my 3D printed models.  I did paint each of these with a different type and color of paint, just to see what I liked best.  

I reality, just about any paint will work.  I have yet to have one fail on the primed ABS.  

A few bits of wire, and some scraps of styrene for the pedals, and they are ready to go to work.

Road Graders
These are metal toys that I picked up a various trains shows.  The orange one is a newer, slightly less detailed version.  The yellow one, is a Mercury Lil' Toy.  I arrived missing some tires, and had been played with hard.

The orange one was in pretty good shape, only a few nicks, so I applied a little weathering to the nicks.  The main issue was the blob they called a steering wheel.  I finally decided the only option was to cut it off and replace it.

I replaced the steering wheel with one I 3D printed.  

I also 3D printed an air clearer for this model, and added foot pedals and a gear shift.  I also designed and 3D printed the tires.  

The yellow model was sandblasted to remove all the only paint, and then painted with Krylon old Caterpillar Yellow.  
I don't care for the yellow wheels on the orange model, but with some weathering, at least they are not shiny. 

I have since found another road grader, and it not only needs tires, but the grader part as well.  More items to design and 3D print.  

Other vehicle blog posts I have done,


Monday, May 30, 2016

Wall details, 3D printed in HO scale

For custom details, Shapeways is the way to go.  This assortment is all wall details.  Some of these I had printed before, others, this is the first time.  The set includes a lot of parts.

 There are two different gas meters, two of each.

A selection of pipes to run along the walls. 

 Four different wall vents, four of each.  Three of them are see through, the four smallest are surface mount.

 Four wall fans, and two types of electric meters, four of each.  

 Roof drain scuppers.

Two types, eight of each.  Four coal doors, a set of six mail boxes )note the raised lettering for the apartments).  There are also two size of fire sprinkler connections, four of each.  I have since added four alarm bells to put on the outside wall of the building.

There is a large selection of tension rod washers (sometimes called stars).  Nine styles, eight of each.

Here are a few pictures of the tension rod washers.  These are based on prototype pictures, and are used on most older masonry buildings.  These are HO scale, so the are between 1/8" and 1/4" in size.





There are eight of each of the tension rod washers in the set. 

Here is one installed on a building, an old Roundhouse kit.

 The smaller gas meter, and the piping. 

Here is an example of how I used the pipe, and you can also see more of the tension washers.

 Here are the larger gas meter, and four wall mount fans.  

 At the top of the picture  are the fire alarm bells and the eight fire hose connections.  Next down is the apartment mail boxes with raise lettering. And, at the bottom are the scupper (flat roof downspout drain), two styles.

Here is another shot of the mail boxes and fire apparatus.  To the right are eight electric meters, four of two different styles.  The connections can easily be filed off if needed.  

The electric meters installed on an apartment building.

The mail boxes.

Sixteen vents, four sizes.  The small vents to the right are surface mount, the rest are see through, i.e. real vents. You can see the copper penny through the vents.  The coal doors are in the upper right.

I held the larger vent up to the light for this picture.  One has to be very careful to not fill the vents up when painting.

I added a coal door to this apartment building.

Here is a link to these items on Shapeways, should anyone be interested.  https://www.shapeways.com/structure-exterior-wall-details

I did not expect to ever sell the piano store, it was just something I wanted, but I have sold a couple sets, https://www.shapeways.com/piano-store-stock

Here are some links to other details I have designed and had printed at Shapeways.




Tuesday, May 24, 2016

3D Printing in Copper #2 & #3, weathering

Printing with Copper infused PLA part 2

The copper roof ridge, with natural weathering.

In the previous post, I covered some items I printed in copper infused PLA.  3d-printing-in-copper-model-railroad-details  I wanted to take it a step further, and naturally patina the copper (weathering it by oxidation).  A little research, and one finds that Uric Acid works well, but it a little gross to handle, so I went with the second option, Ammonia and salt.  You don't soak the items in it, but rather you fume the copper.  The fumes from the solution cause the copper to oxidize, much as it does in nature. I also wanted to see what would happen if the items fumed for a long time.  How green would they get.  I wasn't totally satisfied with the roof ridge cap shown above.  It had fumed for about 36 hours.  I did not measure the amount of salt or ammonia, and I assume different ratios would produce different results, but I am just playing, not trying to do a scientific experiment.

I put about a teaspoon of salt in a plastic container, and printed out some angle pieces to hold the printed parts up above the solution.  

I used some raft pieces to make a table to lay the parts on.  

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Since I had a bunch of copper raft laying around, I ground it up in a blender to use it as a pile of scrap in my junk yard.  I put this in a plastic bag, and propped it open to make sure fumes would get in.

 I took this picture after 48 hours, and you could tell it was working, lots of copper leaching out into the solution.  The next evening, I was tired, didn't even look at it.

 After 96 hours, I opened it up to see this.  One piece had collapsed under its own weight, and another had warped.  I did not know what to think, so I took the parts up to wash off in the sink.  I threw a paper towel over the drain to keep the parts from getting away.

 Here is the really cool part, there was not much left, the copper had almost completely oxidised away, leaving only some PLA powder.

 After it dried, you can really see how little is left.

 The scrap in the bag, somehow fared much better, and came out great.

WELL, that got me thinking.  How about a test, put a bunch of items in the fuming chamber, and take some out every 12-24 hours, and see how they fair.  So, here we go on that...

Printing with Copper infused PLA part 3

I made four sets of buckets and tubs, and placed them in the container with ammonia and salt.  Placed the cover on it and let it set for 12 hours.

In 12 hours, the solution was a little blue, but the items did not look like they had oxidized very much.

I rinsed them off, and set them aside to dry.  Wet, they were not impressive.

But dry, dang, the looked good.

And after 24 hours, they showed, obviously, more oxidation.  Quite impressive.

After 48 hours, the solution was very blue, showing a lot of oxidation had occurred. 

No reason to continue the experiment, as the oxidation had deteriorated to the point the parts were falling apart. Once the copper was removed, there was not enough of the PLA left to keep the parts together.

So much of the copper had oxidized away that this copper tub was almost white.  It had almost no strength, and was easily crushed.  I crushed them up, and threw them in the scrap pile.

This is the 12 hour fumed items, and they look great.  If I want a little less patina, I will just fume the products for a shorter time.

The 24 hours fumed items shown here, really show the heavy oxidation.  I can't imagine one could need any more patina than this.

I am planning on picking up a rock tumbler later this week, and we will try polishing the copper....