First a bit of background. I volunteer with the model railroad group at Boothbay Railway Village in Maine (http://railwayvillage.org). Our layout is HO scale with a double track standard gauge main line loop and a HOn30 narrow gauge line along two sides of the layout; loop to loop. HOn30 is used to represent 2 foot narrow gauge, and used the same track spacing as N scale standard gauge. Everything runs on a Digitrax DCC system. The narrow gauge track has been in for a year or so, but we have had no operational HOn30 locomotives with decoders, so one of our goals this winter is to get some locomotives operational before the museum opens in May. I have been following forum discussions on 3D printing for a while, and decided that I should investigate what is available in HOn30. Checking Shapeways, I found about 350 HOn30 products are available, and I found a short boxcab locomotive shell that looked appropriate.
The body shell is available in 3 materials:
· White Strong & Flexible - White nylon plastic with a matte finish and slight grainy feel. $20.00
· White Strong & Flexible Polished - White nylon plastic polished to reveal a smooth matte finish. $21.00
· Frosted Detail - Matte translucent plastic with fine print lines that reveals small details. $27.87
The Frosted Detail material offers the most detail. Cost is based on the volume of plastic printed; and the level of detail. One caution on ordering something. Not everything in Shapeways may have been printed to verify the design, just designed and posted online. Part of the ordering process includes a design review by Shapeways; they will refund if they feel the item is not printable. The boxcab arrived well packed, padded and in a zip-lock bag.
When opened, it was covered in a clear, waxy viscous liquid that was a residue from the printing process. I tried removing it with a Zep citrus based cleaner this I use on resin kits. It removed some, but not all of the coating, which affected the primer coat I sprayed – more of this when I discuss painting.
I was pleased with the detail on the model. The plastic is translucent, and is a bit brittle. It should not be a problem in normal handling, but caution is needed drilling holes; more of this when I discuss adding detail parts. In the next section, I will talk about my search for a drive unit.
George In Midcoast Maine, 'bout halfway up the Rockland branch
Locating a Drive Unit
The boxcab is designed to use a Kato drive. I could not locate it searching Kato USA site for the part number. I contacted Customer Service, and was informed that those drives are produced for a specialty market in Japan. One could be special ordered, but they are “not DCC friendly”. We had an N scale Bachmann 70 tonner with DCC that had been purchased for as an HOn30 donor mechanism. The drive seemed to just fit, but when I added the Micro Trains couplers, was no room for it. Next, I checked NWSL web site, but they had nothing listed except HO scale standard gauge. In their reply to my inquiry, they said there were redesigning their drives and had not got to N scale yet. At this point, I turned to the forum for help; I exchanged a few private messages with Darth Santa Fe and HOn30Critter (thanks for the help guys!). In the end I decided the best available drive available was the Bull Ant drive by Hollywood Foundry located in Garfield, Victoria, Australia.
Each drive is custom designed to the buyer’s specification. This is their Bull Ant ordering page:
http://hollywoodfoundry.com/shopdisplayproducts.asp?id=10&cat=BullAnt+Drive+Mechanisms
There is a companion “click for details” page that should be opened in a separate window, as it describes each section on the ordering page. For instance, HOn30 is not specifically mentioned in the Track Gauge pull down menu, but the details page explains that HOn30 is the same as “HOe or 9mm”. The basic design dimension for the Bull Ant is wheelbase as the drive is mostly used to replace a locomotive power truck. I sent them an e-mail with the dimensions of the available space in the interior of the boxcab; and explaining my problem. In about an hour, had a reply from Geoff including a CADD drawing of the Bull Ant that would fit. The Bull Ant I ordered includes a 31:1 gear drive, it is wired for DCC, has a Mashima MK1024 motor, and a flywheel. It is about 1.6 inches long.
A couple of comments about ordering. All prices are in Australian dollars; the ordering page includes a link to a currency conversion site. Prices include a 10% Goods and Services Tax, I think similar to VAT in Europe. This is deducted on the checkout page when ordering to an overseas location. Air Mail shipping was AUS$17.60.
I am very pleased with the quality of the Bull Ant. I have run it on direct current on a small section of n scale track. It runs smoothly; but, according to instructions, it needs to be run in for a couple of hours.
Next, adding detail parts
Adding Detail Parts and Painting
As have mentioned before, the boxcab shell is made from a plastic that is brittle and translucent. When I started to put on grab rails on the doors, I had trouble seeing the door outline, so I outlined the door with a pencil. The pencil line is easily visible from the inside of the shell.
I made the headlights from 3/16” Evergreen tubing. I used a hand drill for better control, and started with a 1/32” drill and went up in sizes, drill by drill, until I got to 3/16”. The first hole went OK, but the second cracked the plastic from the hole over to the window. I tried gluing the crack with CA, but it did not hold. In the end, I used my Dremel grinder at its lowest speed with a conical grinding bit, slowly increased the hole to almost 3/16”, and finished it with a round file. I have added details including horn, bell, steps in one side to the roof, grab rails for the doors, and an exhaust pipe with muffler. Once I have the height established, I may add a step below the doors. CA does not seem to be a strong adhesive for this plastic.
When I added the door grab rails, I decided to give the shell a coat of primer using Rustoleum grey paint. The paint did dry to the touch, but did not really set up. Even after a few days it was very soft. I decided to strip the paint, but was reluctant to soak the shell in 90% rubbing alcohol with an unknown plastic. I soaked a paper towel in rubbing alcohol, and scrubbed the paint off, while checking the plastic for softening or other changes. There appeared to be no problems, and almost all the paint was removed. I did notice some waxy residue remaining in places which I scraped off with an X-Acto knife. This is the shell with details added.
This is where I am as of today, Feb 24. The next step is to figure out how to mount the Bull Ant and set the body to the correct height for the Micro Trains couplers. Then final painting, decals, decoder installation, and a few more detail parts
George,
This is going to be a neat little critter.
Does Shapeways provide any suggestions on cleaning up the part? Or for glue? You're doing well with adjusting around things, but someone with less experience could be stymied at several points you're worked through.
Mike Lehman
Urbana, IL
George
I have been looking forward to seeing your thread on the construction of this wee beastie. Looks pretty good so far. I'd be interested in knowing what things you might have done differently, if any.
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
mlehmanDoes Shapeways provide any suggestions on cleaning up the part? Or for glue?
Shapeways indicated the wax residue should not be a problem. I do not recall any discussion on adhesives, but it has been a while since I looked at that part of the site. My basic approach was to treat it like a resin kit until I found something different.
hon30critter I'd be interested in knowing what things you might have done differently, if any.
So far, the only thing different might have been buying the long boxcab instead of the short one. With that body, I probably could have used the 70 tonner mechanism. Basically, the purchase is an experiment and quality test to see if the process would be something I would want to do again; the answer is yes.
I have my eye on a conversion kit for making an N scale 4-4-0 or 4-6-0 into a HOn30. It includes a replacement cab, tender, pilot, stack and domes. The cost of the kit is about the same as the boxcab, but the donor loco would be more expensive.
I am looking forward to developments. I would like to try my hand at some sort of small boxcab sometime, but would likely do it in HOn3. Then there's some logging stuff, like a crew speeder, that is of interest. I've been avoiding looking at shapeways, too much temptation. Gotta get my Jonan SP GE #1 fixed first.
Been trying to quit diesel, but got a habit, a very bad habit...
MIke, I checked Shapeways, and they have 77 products listed under HOn3. Lots of parts; a few passenger and freight cars and some cabooses, but no boxcabshttps://www.shapeways.com/search?q=HOn3
Searching for boxcabs, I found 26 in various scales; maybe something there would work for youhttps://www.shapeways.com/search?q=boxcab
Great work on your critter, wonder if that On30 gas electric could be configured for S standard guage? Too tempting!
Thanks for poking around to get me a little info while I avoid temptation.
So, is there anything about your boxcab that would keep me from putting a HOn3 Bull Ant into it? I suspect the listings reflect the designer's intent, but likely don't cover all the possibilities.
The 3 ft gauge Bull Ant would be 6" scale wider than mine which should not be a problem. The length would be dependant on how far into the shell your coupler boxes extend, that was the controlling dimension on mine. This is the detail page for my boxcab. https://www.shapeways.com/product/DJ9GRJBGY/hon30-short-boxcab-loco?modelId=203528&optionId=42972915
He also has designed a longer boxcab; mine is 2.38: long, this is 3.88" long. The longer one probably would look better with 2 trucks (B-B); Hollywood foundry can provide a matching dummy truckhttps://www.shapeways.com/product/Z4FTJZGH8/hon30-boxcab?li=search-results-1&optionId=43637840
Wax Removal
G PaineG Paine wrote the following post 5 days ago: mlehmanDoes Shapeways provide any suggestions on cleaning up the part? Or for glue? Shapeways indicated the wax residue should not be a problem. I do not recall any discussion on adhesives, but it has been a while since I looked at that part of the site. My basic approach was to treat it like a resin kit until I found something different.
Shapeways describes the Frosted Ultra Detail (FUD) production process as follows:
During printing, Frosted Detail and Frosted Ultra Detail products are supported by a waxy material that is dissolved after printing is complete. This support material changes the texture of the product, making it slightly rougher and less transparent, and making stepping lines more visible. When printing in Frosted Detail, support material encloses the entire product, giving it a slightly lower quality but more consistent finish. When printing in Frosted Ultra Detail, only some portions of the product touch the support material, so the final product has a slightly inconsistent finish, but overall higher surface quality. We recommend Frosted Ultra Detail for any models that will be painted, as painting can make print lines more visible.
When printing is finished, we remove the models from the tray and put them into an oven that melts away the wax support material. Next, we put the models into an a ultrasonic oil bath to remove any remaining wax residues, and then a ultrasonic water bath to remove any oil on the model. Finally, we inspect the models and dry them by hand.
For more detail: https://www.shapeways.com/materials/frosted-detail-plastic?li=navThere is a good video 'How its 3D Printed' near the bottom of the page.
Yesterday afternoon, I took some time to poke around the Shapeways site for more info on wax cleaning and adhesives. I ended up where I should have gone 2 months ago, the Shapeways Forum. There is a forum on Post Production Techniques that I found very useful; in particular, I was looking for references to FUD - Frosted Ultra Detailhttps://www.shapeways.com/forum/index.php?t=thread&frm_id=95&&start=280
One lengthy discussion "FUD Wax Removal" was very helpfulhttps://www.shapeways.com/forum/index.php?t=msg&th=5438&start=0&
Note: the amperstand & on the end did not get linked, so you may copy/paste to get it to work
This discussion, started in 2011, covers just about any material for removing the wax and oil from the printed item. Even with the cleaning mentioned above, a residue of the wax and oil remains on the model that messes up painting and gluing. The most common materials for wax removal seem to be 90% rubbing alcohol and acetone. One guy did an experiment on how long to soak in acetone, concluding not more than 10 minutes, followed by scrubbing with something like an old toothbrush. Longer than that could cause damage. Heavy wax can be removed by carefully scraping with a hobby knife. Another product mentioned is Bestine, which is available at stored like Michaels. Read the container before buying, it could be a bit nasty, but so is acetone. Gloves and good vents is necessary.
Adhesives
The wax discussion, above, got a bit long so I am starting another short one about adhesives.
I had mentioned before, that CA did not give a strong bond on my detail parts as it does on styrene, so I was looking on the forum for info on that subject. Not as much discussion, but 2 part epoxy and silicone sealer seem to be the ones favored the most.
I am looking for something that will mount the Bull Ant, and will try 5 Minute Epoxy
Thanks, really good info to know.
I can definitely see the couplers being an issue. A longer unit seems more adaptable there. Then I may just go for one of the B-B drives that Hollywood Foundry offers, because that couldn't hurt with my grades. I haven't been over to HF's site recently, but know I may find that the shortest B-B drive may still be too long for even the longer boxcab. In whcih case, the suggestion of using a BullAnt + dummy truck may well be the solution.
This did get me to thinking though...What if the ends were cut from the boxcab shell, then the body was stretched/built-up in between them as needed? Hmm, hmmm
Based on my experience with building and motorizing critters I would be hesitant to epoxy the BullAnt into the shell. The odds on you needing to take it out to make adjustments are fairly high, and with the shell being brittle, you could end up with a hand full of pieces.
My preferred approach is to mount tabs inside the shell which can be drilled and tapped so the drive line is easily removable. I believe I can see a mounting strip already installed in your BullAnt so all you need is some small screws and the brackets to attach to the shell
Just a suggestion.
hon30critterBased on my experience with building and motorizing critters I would be hesitant to epoxy the BullAnt into the shell.
Sorry I was not clear, I do not plan epoxying the Bull Ant to the shell, but epoxying some mounting blocks to the shell. I have some rectangular brass tube that I will solder to the bolsters (sticking out from the sides of BA), and attach to the mounting blocks with 2-56 screws.
That sounds a lot more like a modeller who is creating museum pieces! You had me a bit concerned for a minute. I should have given you more credit.
I have recently discovered 90 second epoxy at our local hardware store. It seems to take more than 90 seconds to stiffen up but it does reduce the time required to make the joints.
Mounting the Bull Ant and Couplers
I had installed the mounting brackets for the couplers earlier since their location is determined by the top of the coupler openings on the front and back of the shell. I use 6x12 Evergreen strip styrene.
The first step in mounting the Bull Ant was to confirm that there is enough vertical clearance between the coupler pocket and the bottom of the foot boards. The low coupler shows there is clearance and the foot boards do not have to be trimmed.
The next step is to determine a mounting height for the Bull Ant. First I added strip styrene under the foot boards until the coupler height was correct. Then I put the Bull Ant inside the shell, and, with the styrene pieces in place under the foot boards on the track, I made sure the Bull Ant was firmly on the track as well. When I lifted it off the track, I marked the under side of the brass Bull Ant mounting bracket. From that, I calculated the height of the styrene mounting bracket, and drew a line at the bracket installation height in the sides of the shell.
I made the mounting brackets from 2x12 Evergreen styrene. To give more gluing surface, I added an upright 2x12, and reinforced the joint with a 6x6.
I used 5 Minute Epoxy to attach the mounting brackets. (See my discussion on Adhesives, above, to see why I did not use CA. Posted March 2.) I installed the brackets a bit high, and brought them to the correct height by shimming with strip styrene. Note, the arrow in the inside roof indicates the front of the boxcab.
Next, on to the paint shop, followed by decoder installation, and a few more details to finish.
George:
Looking good.
You probably already have this covered, but are you going to add some weight? If so, one of the ways that could be done is to replace the styrene mounting brackets with ones made from lead. However, since the brackets are already epoxied into place it may not be worth the risk of trying to replace them.
Here are a couple of pictures showing the inside of the shell of a Grandt Line 25 tonner that I am working on. I bought a couple of square feet of sheet lead 1/16" thick. Its easy to work with and it just fits in the jaw of my nibbler shears so cutting it to shape is not hard at all. I'm using the Bull Ant drive for this one too.
I put a brass cover over the flywheel to prevent wires from rubbing on it. The decoder goes in the top of the engine compartment (Loksound Micro Select just fits) and the twin iPhone speakers go in the roof of the cab. All the wire connections will sit on top of the flywheel cover.
Dave, All that small with sound!! You must make a video when it's done so we can hear it.
I have not weighed the boxcab, drive and other stuff yet. The instructions say it can weigh up to 4 oz for better traction. There is still room inside, but it seems top heavy already. There is room to add weight above the coupler brackets. I will look at that after painting.
I like the idea of the cover over the flywheel, there are a lot of fine wires to snag on moving parts.
I have to give credit to the late Wolfgang Dudler for the idea of putting sound into a 25 tonner. I'm following his example except for the sugar cube speakers.
With the addition of the lead I've got the weight up to just over 3 ounces. I could squeeze some more lead in if I put it behind the cab windows, but I'm going to try it first to see how well it runs. I don't like the look with the windows filled in, and I want to install an engineer (or parts thereof).
One possibility is to remove the flywheel and put a Loksound Keep Alive in its place. They are about the same size. Before I go chopping the shaft off the motor I will send Hollywood Foundry an e-mail asking what they think of the idea. I'll let you know what they say.
EDIT: I decided to explore the Keep Alive option a little further, so I just ordered a BullAnt without a flywheel, same specs otherwise. The Loksound Keep Alive will fit quite nicely in the cab where the flywheel was, and still leave room for the sugar cube speakers. I decided that it would be too risky to try to remove the flywheel from the BullAnt I have now. I'll use it for another critter project yet to be determined. I had to remove about 3/4 oz. of lead to fit the Keep Alive but I'm sure I will be able to put most of that back in place once the drive and circuits are installed.
Time for a quick update, other projects and the Real World seem to be slowing things down. Here is a recent boxcab photo after a trip to the paint shop and decals.
Got a few more details and the decoder left to finish the project.
Looking good, George.
I'm probably just not remembering, but I assume there are some sideframes to eventually make things look less naked down low?
It is DONE at last. I finished the boxcab yesterday. I installed a Digitrax DZ123PS decoder and LED headlights. I also added skirts to the sides on teh bottom using Evergreen 4x12 scale styrene strip. I secured it with plastic compatible Liquid Nails as it is an area where people will tend to grab it when picking it up.
This afternoon, I took it to its new home at Boothbay Railway Village, and gave it a test run. The drive sounds a bit noisey, but the instructions say it needs about 2 hours fast running to run-in the Bull Ant. We could not do this today as the track was too dirty for continuous running due to a winter of scenery and plaster work. Here is a short video:
It looks really good George!
Thanks for posting on the Hollywood Foundry thread.
I sent an e-mail to Geoff at Hollywood Foundry this afternoon with a link to this discussion and to the video. Geoff thought the drive sounded noisey; I will have to check on it when I go over to Boothbay next Thursday.
I checked the boxcab and Bull Ant today, and found the end one of the brass supports I installed to mount the drive was touching a piece of lead weight. That was transmitting the sound into the body shell and amplifying it. I did a bit of filing so it was not touching and that quieted the sound to a reasonable level.