3D printing surface finish help

[Dave Schneider]

Is Bestine, the obvious to me, not applicable for this RP project. No heating necessary and it works wonders on the wax residue, especially on FUD.

I think the point here is that people are looking at various solvents to smooth the surface of  3d printed models AFTER the wax is removed by Bestine or equivalent.
Here is a post-Bestine Fairbanks-Morse shell showing the problem.



Best wishes, Dave

[havingfuntoo]

Brian, it is good that you (and all the others like you) bring to our attention different ideas and suggestions and share some of your experiences and knowledge with us. There will be a lot of us that have taken something suggested by someone (like you have done) and refined the idea into a work of art admired by all that see it, rarely is the person that inspired the process given any credit for it.

I know I have seemed to be challenging on some of the safety aspects of some of your suggestions and ideas, but I think it is important to point out the dangers I recognize in the tasks being performed. It would upset me immensely to know that someone, maybe even you Brian, had hurt themselves when I could have posted an alert that would possibly prevent it.

All of us have various skills and knowledge, when they are mixed together in the stirring pot of a forum such as this we all gain the benefit of the mix. Because I know some thing you don’t does not make me any better than you, and I will bet there are a heap of things you know that I do not. If I don’t listen I don’t learn! With out the presentation of ideas and the banter that follows none of us will develop and advance to the degree we will with it. To belittle someone for pointing out what they know to be a hazard is saying more about you than it is about them.

Please accept my apologies if you feel I have been harsh with you. There is no malice in what I write or suggest nor should you (or anyone else) see it as something negative or intended as such.

A piece of rope is made up of many strands; it is only when they all bind together that the ropes strength is obtained.

[HuskerN]

I have started using a toothbrush and toothpaste after a bestine bath to remove the "fuzz" that remains on some of the surfaces.  Then, a small file or sanding stick for the remaining areas that need a little attention.  My truck models are much smaller than a locomotive shell, so I can see how the issues might be exaggerated, and perhaps unsatisfactory to some. 

I know there is a lot of discussion about 3d printing, which is great, since it is a newer technology, and enables a regular guy like myself to design a model at a home computer for free, upload it to a service like Shapeways for free, and then pay for as many or few models as I want. 

I realize that 3d printing is not the holy grail, and some folks simply aren't willing to accept some of the less than optimal results, and have said this multiple times.  However, I have about a dozen truck/trailer models now that have never existed in N scale, and may never exist other than my own personal designs.  And, I can continue to design more into the future, and hopefully the quality of printing will only get better over time. 

I agree, let's keep the Dr. Phil discussions out of model railroading, and keep the constructive discussion going.  We will only benefit from everyone's experiences here.

HuskerN

[peteski]

Like you and mockery.


Here's your post:
What's the opinion part again?

Jason

Jason,
My post you quoted had three sentences.  First one was my opinion (however you want to interpret it).  The other two were valid questions.  No?

[Dave V]

Take it outside, people.  Tired of the bickering.   

[delamaize]

Take it outside, people.  Tired of the bickering.   

this.
 

[Alaska Railroader]

OK, this I know something about. About 3 years ago when Shapeways was new to me a good friend drew up a bunch of Z items (sorry but Z was all I did then) to help fill the void in that scale. I ended up spending thousands (ouch) on RP vehicles and airplanes to sell for the company. I got my money back but it was very clear to me right away that it wasn't going to be me doing the painting! I didn't know about Bestine back then but even though it would have helped some I would still have run into the very problem you are discussing.

To the best of my knowledge and through handling thousands of RP pieces I can pretty much assure you that there is nothing you can do chemically to make the surface look the way you want it to. Since those early days I have found out that spraying a primer on first (white, trust me) then hand brushing the colors on you can fill those rastered lines in somewhat to make your model have a more, um, graceful coat. I then put a clear coat over the whole thing. I was also able to make some full body decals since they were small, this helped tremendously (see the GM Fishbowl bus below).

This is my experience, I don't claim to be the final word but I think my failures and successes could help keep you from failures and probably have much better success than I did.

I'd show you some better stuff but I have tens of thousands of photos and the newer stuff is mixed in them, these were in one file, they are my first trials.

[DKS]

Personally, I'm not of the mind that chemically treating FUD to essentially melt the raster lines away is a viable approach, except possibly in rare instances; there will almost certainly be loss in detail. I am intrigued buy the recently-recommended toothpaste trick as possibly a bit more benign than attacking a model with ammonia and/or heat and/or some other nastiness, since the area getting the toothpaste treatment can be controlled to a certain degree.

I'd also like to point out the good results with the Shapeways PRR position signal. Here we have something akin to what Karin (Alaska Railroader) is talking about: a relatively heavy application of paint to disguise the raster lines. In this case, I think the first layer of chrome (used for light-tightness) has a lot to do with the final finish. However, this will almost certainly cause issues with highly-detailed surfaces once again.

I'm not opposed to experimentation by any means; however, I don't think there is a silver bullet that's going to turn FUD into injection-molded styrene. My gut says it may take a combination of multiple different techniques, possibly applied selectively, to suit the various challenges presented by different RP models.

[3rdboxcar]

Hi

Totally agree with Alaska Railroader's comments.

I just received a set of test prints for my CNSM interurban's, gave them a clean in Non Acetone nail varnish remover [bestine not available in the UK] [couple had to be done twice]. I then tried the toothpaste suggestion on one model and it did not make any difference that I could see. When I looked again this morning I cannot remember which one got the toothpaste treatment. My models are printed in FUD.

FUD is quite a hard material and wonder whether some of the other materials would work with the toothpaste idea.

I do use a fibreglass pen to give a gentle rub of the surfaces, which I am not sure that makes any difference either but does remove any dry residue.

Alexander

[6axlepwr]

havingtomuchfun: No offense taken. Safety issues need to be pointed out as well. The way they are brought up makes a difference in how they are perceived by the reader. I was not at all aware of the possibility of alcohol fumes igniting. But I have always done the paint removal process in a well ventilated area because I do not like the smell of the fumes.

Alaska Railroader: your post is exactly what these forums are good for. you have the experience and are willing to share it with us. Thanks.

When I was modeling in HO, I had a lot of items printed at Shapeways. Some of them were useful because I could scrape the print lines away. Others like a 2700 gallon fuel tank were totally junk. The print lines were so heavy that no amount of scraping would clean them up. Actually three parts were useful that I got made. EMD coupler pockets for Kato models, Alco coupler pockets for the Atlas models and air reservoir brackets and tank ends for the GP7/9. These had surfaces I could scrape with a knife and clean up. Afterwards, I would grit blast them with 200 grit aluminum oxide at 100psi. That smoothed out the surface pretty nicely, but it was the scraping that cleaned it up the most. For small N-scale parts though, I think scraping the lines away would destroy most of the part.

If Shapeways would invest in higher resolution machines, then the line problem would be almost gone. I do not know what the resolution is for the machines Shapeways is using. I am thinking on the range of 100um/layer for FUD. That is 0.1mm or 0.004" per layer. That is pretty rough for N-Scale. I do think the time will come though when higher resolution machines come online for shops like Shapeways. Heck, if I had the cash to buy just one machine you could pretty much make a decent side business out of running it for all the model railroad needs. These higher resolution machines though are big $$$$$.

[3rdboxcar]

Heck, if I had the cash to buy just one machine you could pretty much make a decent side business out of running it for all the model railroad needs. These higher resolution machines though are big $$$$$.

I remember watching a you tube video from shapeways and they said their FUD machines cost just under $1,000,000

Alexander

[Sokramiketes]

I remember watching a you tube video from shapeways and they said their FUD machines cost just under $1,000,000

Alexander

Wow.  Perfactory is an order of magnitude less, ~$60,000 last I checked.  Wonder if there is a speed or build volume issue with them buying better machines than the FUD ones.

[pnolan48]

I think Shapeways has bought big volume machines, as one order is massed with many others. That would explain some of the cost.

[6axlepwr]

Dave,

That is some pretty nice design work. Really nice. What wall thickness did you use on your foot board side kick plate? Looks to be maybe 0.010" or less. If it wasn't for the print lines, that shell would have turned out darn nice.

[jmlaboda]

Anyone care to take a chance at attacking the roughness on one of the FM cabs to see if it will work well in removing the roughness?  If it works then there is hope in making other rough surfaces smooth as well.