Using Sketchup for 3D Printing Design

First, I want to say that I am by no means an expert in the area of 3d printing, having only been doing this for a couple of months.  But since this technology is so interesting, I thought I would keep posting my experiences here, so that others interested in becoming more knowledgeable might learn a thing or two reading about what I am doing.  Or others helping me to learn more from their experiences.

The great part about 3d printing is that it can be free to get started.  I use Sketchup for my designs, which is a free download from Trimble.  There is a huge online community, and plenty of resources available for the newcomer.  Once the design is ready for printing, there are multiple printing services available to print the finished model.  For N scale, however, it seems that the best choice is Shapeways.  Other companies either don't have the "frosted ultra detail" material needed for fine detail, or their print resolution just isn't quite small enough.  Of course, I am very new to this myself, so there could be other alternatives that I am not aware of.  It is also free to upload a design to Shapeways, and then only when you wish to actually purchase a print, do you pay for their services.

So, while it seems straight forward to get an image in your head, onto a computer, and loaded to a printer at Shapeways, it actually takes some experience in design, understanding how to convert 1:1 scale to 1:160 without making detail or parts too small or thin, and modeling within the design specifications defined by Shapeways.  Again, I am still in the "don't know what I don't know" phase, so I am eager to learn more.

Here is an illustration of Sketchup, and a model that I am currently designing.  It is a 53' Wilson spread axle livestock trailer.  N scale desperately needs a modern livestock trailer, and I need a few for a planned industry on the Council Bluffs Sub.  I have high confidence that this will be a successful model like my grain trailer, however, my main concern is whether the printing process and resolution will be able to handle the numerous ventilation holes in the side skins of the trailer.  So, this will be a good test for me.  The belly dump trailer that I designed is much more conservative, and should turn out just fine.  I will know more this week when my first batch arrives.

3D Printing - Preparing the Raw Print for Painting

I wanted to share some model preparation steps, since this is very important in getting a great finished product.  The raw print from Shapeways is transparent, covered in a waxy like residue, and in some cases can look rather rough.  I did some research on the internet to see what people were doing to prep these models, and what type of paint to use.  The following photos illustrate what I am doing, but don't necessarily mean best practice.

First, I use a bath of Bestine brand heptane to soak the model overnight.  I then pull them out, rinse them with water, and let them dry.  Here is where I have seen some variance in my Shapeways orders.  It is obvious after observing the raw prints, that items can be printed using different orientation.  I shared this in an earlier post, and will show some examples.  Since each item is printed from the bottom up in layers, the supporting material used to hold the existing layers together during printing can leave a less than ideal surface.  It's not until the heptane has done its job removing the waxy residue that this becomes apparent.  Here is a great comparison of the two Pete cabs that were printed in the same batch.  One cab is nice and smooth, and the other will require some prep work:

What am I using to get the surface of the model smooth and ready for paint?  So far, I have found that a sanding needle works well for corners and cracks, and a medium sized micro brush will remove most of the flaky residue that is left after the heptane soak.

As far as the rest of the Petebilt parts, the frame turned out well.  I added some detail, but decided to not go overboard since this is N scale.  There are simulated airbags, springs, and shocks on each axle.  

The grill/bumper part, and the air cleaner canisters are a perfect fit, and only require some minor cleaning where they fit into the cab component.  These are exceptional prints, and show just how much detail can be obtained.

Here is an example of a grain trailer right out of the Shapeways box.  It is transparent, and has a thick waxy coat.  After a bath in heptane, it becomes white like styrene, and the details can be more easily seen.  I am sharing a photo of the tire/rim sets to illustrate this best.

Overall, I am pleased with Shapeways and 3d printing in general.  As you can see, it is not perfect, and models with differing results can be frustrating.  However, I am making the best of this newer technology, and hoping that it will continue to improve over time.  Unfortunately, the orientation of the model during printing is out of my control, and Shapeways will not accept requests for specific orientation at this time.  This is a shared concern by many designers based on public discussions I have observed online.  

I have a few models available for purchase through Shapeways now, and more to come in the future.  If you purchase one of my models, please let me know about your results.  My intent is to purchase and finish every model that I design before making it available publicly to ensure that it turns out as intended.  

http://www.shapeways.com/shops/NScaleAddict

3D Printed 379 "Pete" Day Cab Straight Truck

The UPS truck arrived late today with one of my new 3D printed models from Shapeways.  I haven't done anything with the model yet but wanted to share it on my blog since I'm pretty excited about this one.  I have always been a fan of Peterbilt trucks, and wanted an N scale version for myself.  While GHQ makes a decent model, I felt that I might be able to design and print my own with a similar level of effort to customizing the GHQ model into what I need.

I have already shown photos of my 22' grain box and have them available for sale through Shapeways currently.   Well the photos below illustrate what I had in mind to hold up that box.

This a model designed after a 379 Peterbilt truck.  The frame was designed specifically for the grain box.  It features a tandem axle, with a third lift axle in the rear.  I designed it in the raised position.  The single fuel tank is representative of a short haul or farm truck.  The battery boxes, air tanks, and cab steps are all part of the frame and add to the integrity of the frame component.  The cab is a separate shell for ease of painting and detailing.  I designed the air filter canisters as separate details for the same reason.  The grill and bumper were designed as a separate component again for that reason.  If I want to swap out a custom grill or Texas style bumper for example, I can easily change that isolated piece.  Also, the individual pieces should aide in the painting process and provide a much cleaner finish between part lines.  The wheel and tire sets are similar to what I am using on my grain trailers. I put the little parts on a spruce for ease of handling.

You will notice that I have 2 cabs, with different style sunshades.  This is yet another great feature of model design and 3D printing.  I'm excited to get these to the paint shop.  My plan is to make multiple configurations of axles, fuel tanks, sleeper options, and other options.

This model is fresh out of the box, so you are seeing it at the same time I am.  I will have more feedback to offer once I clean the parts and test fit them together.  The raw prints still have the waxy residue on them, which make them difficult to see in photos.  Once these are soaked in heptane overnight, they will look like white styrene.  I will cover my steps to finish these models in more detail in future postings.

Tell me what you think.

3D Printing - My New Addiction

I have been having a lot of fun designing N scale models for purposes of 3D printing.  I seem to have narrowed in on trucks and trailers currently, which not only represent a major void in N scale, but will also provide the greatest opportunity to enhance my future Council Bluffs Sub layout project.

I recently completed a design for a Trail King belly dump trailer, and am in the process of validating the actual printed results from Shapeways.  I liked this trailer for its open frame design, and because belly dump and side dump trailers would make great models for N scale construction scenes.  My specific model will feature 3 axles, and steel rims, which I modified from my original aluminum rim design used on my Wilson grain trailers.

Here is the 3D rendering on my Shapeways shop.  I haven't made it available for ordering, since I want to validate my design, and produce a finished model first.  This model has a lot of interesting design features that should result in a neat N scale model.  My Shapeways Shop: http://www.shapeways.com/shops/NScaleAddict

I shared in an earlier post that I had a tarped version of my 43' Wilson grain trailer in design.  Well, I finally completed it, and I have an order on it's way.  I'll share the final result in the near future.  This is the 3D rendering on Shapeways, and again, not available for purchase just yet.