A journal following the history, design, construction and operation of Bernard Kempinski's O Scale model railroad depicting the U. S. Military Railroad (USMRR) Aquia-Falmouth line in 1863, and other model railroad projects.
©Bernard Kempinski All text and images, except as noted, on this blog are copyrighted by the author and may not be used without permission.
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December 31, 2020

The Year in Review and What's Next

Farewell 2020

2020 was the kind of year that is better off forgetting. It started off well, but then the pandemic hit and went downhill from there. We had floods that forced us to seek a solution that works (so far so good!), then hip surgery, which thankfully was successful. In November, my mom fell ill and passed away, which was a heavy, if not unexpected blow.  The holidays were quiet as we all stayed home. But among the sadness and pain, there were some positive developments.  Let's look at the highlights.

I started the expansion of the Aquia Line into the TV room. The initial section, the Belle Air  farm and Division HQ scene, came out nice, and the new track arrangement operates  much better than the previous one. 

I presented two talks about model railroading to groups that are not traditional model railroaders. One was a 6 minute Pecha Kucha talk,  and the other a longer, more detailed talk on civil war era railroads to the Union League of Philadelphia. I also received an encouraging note from a 6th grade social studies class in Wilmington, Delaware that were inspired by my blog to build a portable model railroad of the construction of the Panama Canal. That was great news. 

In April I officially became a NMRA Master Model Railroader. Beyond that, I checked off two retirement bucket list items, learning how to do 3-D drafting/ making a 3-D print. I am still a neophyte in both areas, but I am well on the way to learning more and getting better results.  Armed with those skills and inspired by Eric Gate's HO scratch build, I also started scratch building a locomotive, another one of my retirement bucket list items.

A few days ago I ripped all the plywood I need to finish the layout expansion. Hopefully, the next few months will see the gandy dancers laying track to the new sections. At some point I have to decide if I want to keep Aquia Landing as is, or do the more radical expansion. We'll see how the situation evolves.  I am due to write an article about it with a deadline approaching, so I need to decide soon.

The pandemic seems to have caused a spike in business for Alkem Scale Models. I had my busiest year ever. It helps that some of my products got excellent reviews on other websites.

In between the train projects, I have been doing a lot of other non-model railroader related things. So I have not been idle.

 I have been doing some woodworking projects, working on getting my  "History of Porsche Racing" display built, and some wargaming. With regard to the latter, I am working on a battle board for a new game based on the battles on the Eastern front between the Soviets and the Germans.  The idea of those battle boards is that they will stack up and store in a very small volume. The game scale is smaller, so less room is needed compared to the larger scale gaming I had been doing. So, there has been a lot of stuff going on.

 2021 will mark my 13th year of blogging. Thanks for sticking with me.


December 24, 2020

MERRY CHRISTMAS 2020


Hope you enjoy your holiday.  
Let's look forward to clearing the snow (and viruses) 
to get the Aquia Line running again soon.

 

December 18, 2020

One Day Builds between Printers


Diablo III on the Christmas mantle seems like an appropriate decoration for the year 2020. The glowing eyes are made with 
an LED powered by a battery in the pedestal.

It have been a super busy time in the past two weeks. Since my last post a lot has happened. The big news is that I upgraded to a better 3D printer.  The Anycubic Photon that I bought a few months ago was just not worth investing any more of my time. While it could give decent results, I was getting about a 50 percent success rate. When prints take 6-16 hours, a failed print is a big set back and waste of time. So I ordered and received a Form 3 from Formlabs. It's more of a "professional" grade 3D printer that uses low force, laser stereo lithography. This should make more reliable and better finished prints. Plus, Formlabs was started by 3 MIT Media Lab guys - us Tech Nerds have to support each other. 


Anycubic Photon on the left and Formlabs 3 on the right
I'll talk more about the Form 3 (F3 from now one) later when I have more experience with it, but so far I have had a 100% print success rate

Before I ordered the F3, I sent the locomotive frame stl file to Shapeways for a test print. I did that to evaluate the fit, strength, etc. That print cost about $50 and took about two weeks to get here. Note it was too big to print on the Anycubic Photon.

While I was waiting for the test print from Shapeways and the new F3 to arrive, I decided to work on a few small projects. If you watch Adam Savage's Youtube show called "Tested" you will be familiar with one-day builds. They are small projects that he can build in a day in his incredibly well equipped and stocked shop. He makes replica movie props, scale models, tools, clothing, costumes, and all kinds of things.

So I did some of my own one-day builds. I made some Christmas presents for relatives in my shop, Then, being inspired by Adam Savage, I  made a statute of the title character  from a computer game that my kids and I played, and I still play occasionally, called Diablo III.  Diablo is the evil enemy boss you are fighting in the game.

I made the statue from a stl file I downloaded from Thingeverse. The figure is not exactly the game character, but it was close, and it was free. There are stl files that more closely resemble the game character, but they were somewhat costly. 

I printed the free version of Diablo III on the Anycubic Photon. The prints were not perfect, they had a flaw in the back, but I was still able to use the pieces with some sanding and putty. Since the Diablo character appears to be made from a glowing lava-like substance, I added an LED in the head to light it up (n.b. Diablo has no gender, it assumes the identity of the person it possesses. In Diablo III , that person was a woman. Hence Diablo III has some female features.) To further the effect of glowing lava, I used some florescent paint, which looks creepy in UV light.


With the statute painted and illuminated, I decided to build a pedestal for it. So I went to Woodcraft and picked up a piece of ebony wood for the pedestal. I shaped the wood in my shop. Any excuse to use my wood working tools is OK with me.

So my one day build took two days. But it was a fun diversion. Then the test printed locomotive frame from Shapeways arrived and a day later so did the F3. So back to the locomotive. 




First print of the loco frame on the F3

The test-printed frame from Shapeways looked OK and was surprisingly strong, but it had a few glitches. So, one of  the first jobs for the F3 was to print a new frame with some modifications for the locomotive. I decided to try to print the cylinders and cross head guides as part of the frame. This will make installing the crossheads tricky, but it made the whole frame assembly quite strong. 

The weakest point in the frame is behind the crosshead guide  bulkhead  where the frame splits into two rails going to the rear.  To stiffen this section, I added sections of 1/32nd inch piano wire to the frame. I secured those with 5 minute epoxy. 

With the frame bolted to the smoke box and boiler, the whole assembly is very stiff. 

I am a little concerned about wear in the crosshead guides. If I see these parts wearing I have a few options. One, print a new frame. Two, replace the crosshead guides with nickel silver. Three, reinforce the resin crosshead guides with thin nickel silver wear strips.  

Now to get this painted and add the running sub-chassis. The first sub-chassis I built will not fit in this design. This loco has a longer wheel base and uses smaller drivers.

The white parts were printed on the Anycubic while the 
gray frame was on the F3


December 5, 2020

Coffee Wagons and On-Demand Figures

 I recently discovered this website that prints miniature figures on demand. They have an extensive set of ACW era figures.  They offer several scales. 

https://www.speira.net/product-category/american-civil-war/

I ordered several of the Speria figures including some limbers, wagons, and the coffee wagon set.  I never heard of the ACW coffee wagon before, so I looked it up. 

They were built by the U.S. Christian Commission to improve morale. From other research I know the the U.S.C.C. had several stations on the Aquia Line. The timeline might not be quite right as the coffee wagons were patented in March of 1863, which is the month I model.  But, I love coffee, so it's a must have.

The coffee wagon reminds me of how I first became a coffee drinker. Prior to being in the Army I never drank coffee. But, one cold and misty night I was at a bridge site on the Main River near Bamberg, Germany. We had just finished building a bridge and a steady flow of military vehicles were crossing the river over our bridge.  It was about 3AM and the mess sergeant showed up with a Cambro container full of hot, strong coffee. He made the coffee by dumping the grinds in the bottom of boiling water in the Cambro container. Then they would put the Cambro on the back of a jeep to deliver to the bridge site. Driving along in the back of a jeep, the water and grinds were agitated making strong coffee, especially near the bottom of the jug where it was like mud.  So, being cold and tired, I tried a cup of black coffee. Wow, it was great. So, I started drinking it more and more. Later, when I stayed at a German or Austrian gasthaus, or Italian hotels on ski trips, etc, I would drink their coffee, which was always strong. That is why to this day I love strong coffee.  But I do like a like creamer and a tiny amount of sweetness (like 1/8 teaspoon of sugar). 

I think the coffee wagon and figures will make a nice mini-scene on the layout. 

Brian Fletcher from the ACWRRHS also writes about his connection with the Speria Miniatures. He is involved with the Waterloo Uncovered diorama project group.  Waterloo Uncovered is a charity that supports wounded ex-soldiers come to terms with their conditions through the medium of archaeology.  Every year, the charity conducts a dig at Waterloo and, as well as uncovering new perspectives on the battle, the many soldiers who attend enjoy being part of the project.  In the first few years, the focus was at Hougoumont but recently work has expanded to other parts of the battlefield. 

Speira have been generous enough to supply them with free figures for their non-profit organization to complete the Waterloo battlefield 1:1 in 1/72nd, scale.  He has their figures in 1/72nd. 28mm. and 1/48th.   He says all are excellent and reasonably priced.  Most extensive line is ACW.  They are a small company but highly recommended.  Any figure painters who want to join the Waterloo Uncovered project are welcome.  They have need for another 40,000 Napoleonic figures.  There will be over 100,000 all told.  Over 60 painters worldwide and growing. Diorama will be displayed at the National War Museum in England June 2021 if Covid permits. Some figures are free to a good home.  

December 4, 2020

The Many Pitfalls of 3D Printing

If this is starting to seem like a computer blog, please bear with me. Three-D printing is really applied computer science, so you need delve into such arcane matters. Those of you that follow my blog know that I hate when computers take over my model railroad. That is one of the reasons I model the 1860s. I do not enjoy  wiring and dread the thought of maintaining a large fleet of locomotives with DCC technology. But, I can't deny that technology has made modeling a railroad set in this period possible as there is almost no commercial support. I have embraced computer aided drafting of track plans, laser cutting, DCC, battery power, microprocessors, LED lights, and now 3D printing to accomplish my goals.

So with that preface, let's look at another pitfall awaiting the modeler as he explores the dark, sticky morass of 3D printing. To date most of my 3D printing objects have looked incredibly detailed with nearly invisible layer artifacts. That is why I was puzzled by the facets visible in the first prints of the boiler I made. They required a significant amount of sanding to smooth.

Visible facets on boiler sides 

I decided to see how hard it was to prepare the boiler for painting. I primed it with Rustoleum Filler Primer. I sanded it as described in my previous post.  I used 220-400-600 grits to get a nice smooth surface. Then I sprayed with a coat of Vallejo Black Primer which I had on hand. I don't like this primer as it doesn't seem to self level well, and you can not wet sand it. I don't plan to use it again. 

Paint test on an early version of the model
Next, I sprayed a coat of Future acrylic floor polish to get a nice glossy surface. When that dried, I sprayed  the final coat of Vallejo Natural Steel.  This is not the paint I plan to use for the final model but I had it on hand. The results were good in the areas that I was able to effectively sand. But against the boiler straps (which remain unpainted in the photo), and along the firebox, I could see artifacts of the print process. 

This got me wondering if there was something I was doing wrong in the 3D print work flow that created the facets. After some google searches and checking with the Fusion360 help forum I had the answer.

Non-computer jocks can skip the next two paragraphs. In my Fusion360 workflow, I had been using the "Export" command to save the artwork as a .stl file for 3D printing. For some unknown reason, Fusion360 uses a server to do that conversion. So, you have to send the file over the internet and it sends back the .stl file after about 3 or 4 minutes. This option does not allow any customization of the conversion settings. It is also slow as the file has to be sent over the internet. In this case the resulting .stl file was 75MB.

But, there is a better way. If you right click on the object in the Fusion360 component browser a pop up menu with several options opens up. Buried in that list is the option to "Save as stl." If you select this, another pop-up window opens with options to change the settings of the stl conversion, including the option for a "highest" quality file. The default was "medium" quality. Now that was obvious! (sarcasm alert)

For the small objects I printed so far, medium quality was good enough. But on the large boiler the medium setting was not good enough. So I saved the file as a high quality stl. The resulting file was 550MB, nearly 10 times larger. But it saved it nearly instantly. Win-Win.

So I set about printing the boiler again. After 9.5 hours on the printer I ended up with a much nicer product.  There are no visible printer artifacts as you can see in the photo below.

New boiler print on the highest quality settings
 The frame in these photos is a temporary one made with laser cut MDF. I have ordered a 3D printed part from Shapeways using SLA "Accura Xtreme." which according to their website is "Accura Xtreme is a gray and rigid acrylate-based plastic. It is 3D printed using a large format stereolithography (SLA) printer capable of producing small to large parts with high resolution and detail as well as smooth surfaces with limited layer lines. This material is well suited for challenging functional assemblies with a smooth, injection molded-like surface finish." Seems like a good option for the frame.  If that is not good strong enough or is unsightly, I will pursue other options. Once I have the frame, I will set up the motor and gear box and  try to get it to at least turn the front drive wheel.

In the meantime, I have other tasks to do like make the cow catcher, the cab, many sundry other parts,  and prepare the artwork for laser cutting the rods and fine details. Those will be sent to a commercial laser cutter than can handle cutting metal. 









December 1, 2020

Adventures in 3D Printing

Perhaps that title should read "Mis-adventures." I have been proceeding with 3D printing of many of the parts for the Leach locomotive. As I print, I am learning what works and what doesn't. So I am revising the drawings and doing follow-on prints. Combine that with about a 50% success rate on my prints and the process has been slow. 


Here is the WiP state of the drawing as of today. I am learning Fusion360 as I go, so my progress has been slow.  I frequently have to go to the Fusion360 help site or watch a youtube tutorial on how to do things. 

I made things both simpler and harder for myself by using imported elements from my original Adobe Illustrator 2D file. The Adobe Illustrator elements get imported into Fusion360 as .DXF format. This allows me to use the artwork, so that saves time. However,  this also causes some trouble since I haven't mastered Fusion360. For example, I have not figured out how to get the imported .DXFs to line up with the origin on my existing artwork. So the artwork is seemingly placed at random on my Fusion360 drawing space. Secondly, I have yet to learn how to get different sketches and 3D elements (called bodies) to line up automatically. This is trivial in Illustrator, but not so in Fusion360.

On really annoying thing is how the key combinations in Fusion360 are different than Adobe Illustaor and other 3D programs. I have accidentally moved my objects in Fusion360 when I was actually just trying to pan or orbit the view. This causes all kinds of grief as I then have to manually realign things. I tried using the joints command in Fusion360, but that seems to make things even more complicated. There seems to be no easy way to group items to keep them together. Sketches, bodies and components in Fusion360 all have different ways to align and group. It's very confusing.

Also, I have not yet figured out how the time line in Fusion360 works. When it does what I want, it is sweet. Like changing the diameter of a rivet and all the other like rivets automatically update. But other times, I will change the timeline and things disappear or go wonky.

Converting the Fusion360 drawings to 3D prints has also been a learning experience. It's fairly easy to export parts from the Fusion360 file to a format that the printer can take, which is .STL in my case. But getting that .STL file in a format the printer can handle requires additional steps.You have to use software to add supports and then slice it for the printer. There are several programs that do this. I have been using Preform, Chitubox, Meshmixer, and Photon Workshop. 

Prefrom is Formlabs 3D print slicing software. I use it to get suggestions on how to support and slice an object as its automatic support logic is quite good. But it only exports to Formlabs printer formats. So I can't use it with the Anycubic Photon that I own. 

Once Preform gives me some ideas, I use Chitubox to set up the supports. If the file has "errors" they can sometimes be fixed in Meshmixer. Meshmixer has a lot of power to do other things too, like modifying or  drawing your own objects, but I haven't explored it that much yet.

Once Chitubox is done, I have to run the file in Photon Workshop to save as a .PWS format as my printer requires that type of file. 

I have experienced several failed prints usually stemming from inadequate supports. But I also had 2 leaking vats and other sundry problems. 

WiP so far. The frame is a laser cut MDF for fit only. The actual frame will be either 3D printed, or made from brass. The cylinders will be 3D printed in brass.

Anyway, enough boring 3D print nerd stuff.  I have been able to print the smoke stack, cylinders, boiler and firebox sidewalls, and some of the dome.

I tried printing the frame on the Anycubic Photon, but it was too large for my printer volume and would not print reliably. So I sent that out to Shapeways to have them print in SLA plastic. I selected that material as it has a faster turnaround than doing it in metal. I want this first 3D printed frame to test the fit of all the parts. Once that frame arrives, I'll add the sub-chassis and see if I can get it running. Then I can add  the rest of the parts. At that point I'll evaluate if I can proceed with a 3D printed frame, or built by hand with brass stock, or have metal parts laser cut by an external service. 

Some of you have commented on tolerances and shrinkage of the printed parts. Because of the compensated sub-chassis design I am using, all of the tolerances on the parts I have 3D printed so far are not critical. The key issues is making sure the distance between the axles  is precisely the same as the length of the holes in the main drive rod. Those parts will not be 3D printed. 

3D printed stack with laser cut and brass details
I am pleased with the stack, smoke box and boiler print quality. The stack is a combination of 3D printing, a brass mesh for the cinder screen, a laser cut cinder screen support, and a section of flat brass for the screen latch.

The cylinders came out nice too, but I am not sure they are strong enough to use in the working model. I plan to have these 3D printed in Shapeways brass, which uses 3d prints to make a lost wax mold to make actually brass parts.



Sanding and polishing the boiler surface
I am surprised at the strength of the boiler. It is quite sturdy. The 3D boiler had some print layering visible, but I was able to sand those away after a coat of filler primer. The next challenge is to try to paint it to look like Russia Iron.   I ordered some BareMetal foil to try out.

The 3D printed boiler may actually work better than the brass tube I was planning. The reason is that the brass tube is relatively heavy and will raise the center of mass of the locomotive up and to the front. By using a lighter material that is hollow, I can add weight lower and might be able to get better balance. I am hoping that will put more weight on the drive axles to increase tractive effort that the locomotive can provide. 

I need to change the method of attaching the domes to the boiler. I used Fusion360 to match the boiler curvature on the bottom surface of the domes. But, the dome parts have to be supported on that curved face to get a clean print. That means I need to sand away the support residue which can make it hard to precisely match the curve. A through hole that is the diameter of the  dome with a matching internal support in the boiler might be better as I would not have to sand any visible surfaces.