Monday, June 24, 2013

3D Models - Taking a Closer Look

3D printing is fairly new in N scale, and for me personally, I have only been doing this about 5 months now.  In my own experience and also observing chatter on various public forums, there are many opinions about the print capabilities, quality, and cost in producing N scale models.  It seems that a common topic is the texture and horizontal banding that often occurs with printed models, and the difficulty in being able to produce a smooth model.  Of course different designs, print orientation, and quality of machines can produce varying results as well.

I thought it might be a good opportunity to take a closer look at some of my models to illustrate some of the actual results I am getting from Shapeways, and highlight some of the potential trouble spots.  You can make your own judgement whether these are deal breakers, or minor inconveniences in the quest to produce a non-existent model in N scale.

Ok, before I go any further, I must give a shout out to my good friend Bob who passed on to me an earth shattering cleaning technique.  I recently sent him a pair of bottom dump trailers to try, and in addition to using some of the tools I have mentioned here on my blog such as a file and sand paper, he used another very clever technique.  Using an old toothbrush and a drop of toothpaste, he gently scrubbed the models to remove the remaining fuzz that is left on these models after they come out of the solvent bath.  I actually tried this myself and it works brilliantly.  So needless to say, Bob has become a permanent consultant of mine in this endeavor.  I hope to share some of his work soon if he allows me.  Take a look below at some examples of raw and cleaned models.

Ok, here is an example of a pair of truck frames right out of the solvent bath, and a pair after a quick scrub using a tooth brush and toothpaste.  You can see the fuzzy texture of residue that clings to the frame sides and detail, and if left alone would give poor results in the painting steps.  For a model like this with a lot of detail, the toothbrush works perfect.  Using a file or sand paper would risk the details being sanded off or broken.  The two frames that have been scrubbed need just some minor touch ups in the little nooks and crannies, and are nearly ready for a coat of primer.  The time spent and level of effort is about 60 seconds each, and very little pressure applied.

Here is another example of several details right out of the solvent bath.  Again, these may look like a lot of work to get to a clean model, but some minor scrubbing is all that is needed for these to be ready for paint.  Check out how beautiful those wheels and hubs printed.  That is amazing detail.

 Here is my grain trailer after solvent.  Again, very clean model without any work.  Some fuzz around the ladder detail on front can easily be removed with a tooth brush and file.

Here is a pair of bottom dump trailers after solvent.  There is some visible fuzz and horizontal banding on the sides.  A little scrub with toothpaste, and the model will have a very smooth side.

There you have it.  Some close up illustrations of work that is out of the box and out of a bath of solvent.  While this may not work for everything, I am convinced that a printed model can compete any day with metal and resin casting quality.  Of course there are costs and other considerations that make this method complimentary to others, not a replacement.  

The best part of all is that my start up cost to get into 3D printing = $0.00 


  1. The dental solution sounds great but there was no mention of what type of toothpaste. I'm assuming it's going to be an abrasive, is this correct?

    As far as those forum posts, you are going to have opposing viewpoints. I'm figuring that we will have a superior, yet affordable output in the near future that will convince the doubters. In the meantime I'm a true believer in the present output.

    If your aim is to do close-up photography of your modelwork, you may want to wait until the next big thing in rapid prototype comes along but if you're like me and need vehicles and other accessories that stand up well under normal viewing distances, this output works!

    Keep doing what you're doing!

  2. James, good points. I just went to my bathroom drawer and pulled out the crest that I use to brush my teeth. Mint flavor of course.