Charlie, I think we're on the wrong branch... A confessional

As I write this on the train to work for the first time (coming up in the world ;) ), I'd like to reflect on the possible directions this blog could take; for the 5 people who know this place exists, anyway.

As you are no doubt aware, my SLA 3D Printer is taking a god-awfully long time to come to life, partially because of life concerns (my main PC upgrades being a prime example), but nonetheless, i'm beginning construction proper.  The frame members are complete, ready to join and looking pretty good considering this is my first time with an angle grinder!  The Plywood Panels are ready to be assembled as required and accept paint.

Another thing that constantly nags my attention is the fact the virtually no progress has been made on the Shapeways side of Tawe TMD; there are several reasons for this, but the main offenders are:

1. Material Properties – WSF (polyamide) is tough enough for a model railway wagon chassis, but produces lesser detail than early 2000s N gauge models, I.e, the period where it was seriously mooted that this scale was dying!  FUD is acceptable, but far too brittle in tests, with W Irons and springs falling off only enough force to bruise a gnat.
2. Service – Shapeways is under heavy strain right now, it's a new startup riding a technology that is a newborn amongst giants.  These are not a good combination for rapid delivery and processing, with minor changes in models taking 3 weeks to be delivered and a further week for testing and modification.
3. Research – Diagrams of the ancient wagons I intend to populate my Shapeways store with are hard to come by, and when I do finally find them, they’re often fuzzy with poor detail.

1) is unavoidable for the time being, we'll need newer technologies to print more useable materials before I can seriously consider making entire N gauge wagons (chassis included!) in a 3D Printer. 2) is up to Shapeways to sort out, or If another company can sort that out I'd love to hear about them :).  3) is a bitch, but not entirely unsolvable in many cases.  With regards to my current 3D printed wagons (the Metro Brake and the Rigid 8), I'm sorry to say that these wagons are suspended for the time being, while it's possible to make decently detailed models, 3D Printing really has to catch up strength-wise before I can consider selling them as a serious product.  I may consider a hybrid approach of etches and 3D prints, as EtchedPixels seems to be getting on quite well with, but I'll need to learn my way around brass etching first and my first attempts are a stain on my modelling career that shall never be spoken of again.

Somewhere, Bob Symes weeps for future generations...

In other news, I will be visiting the British Festival of Railway Modelling in Doncaster on the 7^th of February.  I've never been to either Doncaster or this particular show, so it ought to be fun on both counts.  This neatly brings me to another announcement – There shall be reviews on this blog!  Oh yes, the time has come.  Given that I now work hours slightly worse than 9-5 (8-6, though I get an hour's lunch in which to write features, or bilge if you refer my personal blog), I'll probably examine smaller products for more intimate reviews; things like whitemetal kits, brass kits, 3D Printed wagons and static objects.  I'm itching to sample the state of our hobby's 3D printed items firsthand, even the best pages don't tell you much about things like ergonomics (for things like handles), surface quality and ease of construction.

As for features, I'm not sure they'll come to prominence for a while.  I am only 23 in a hobby dominated by retirees, retirees who can drop the hammer and call me out with their all-spanning experience!  That's a funny thing about Railway Modelling, it's probably the only industry I know of where you can survive by being stubbornly old fashioned - many business are still able to survive on mail order alone, Dean Sidings being a prime example, and their Pug conversion for the hornby 0-4-0 got a feature in Parker's Guide (a smashing modelling tips publication from Hornby Magazine).  My thoughts are along the lines of ideas about the state of the industry and where we can go from here, and some things damn well need to be dragged into the 21^st Century!

In spite of the ageing demographics our the hobby, I am confident that it will survive, if only because Heritage Lines remain National Treasures somewhere between Stephen Fry and Spitfires.  Despite all the dreadful rhetoric of the “breakdown of family values”, there are still a great many people not quite so blemished, and can thus appreciate there's more to life than power over others.  I picked up a leaflet about that National Model Railway Museum at Ashford at a show, and I can understand why people may be worried by the line “think about the future of our hobby”, but rather than see terminal decline, I see the opposite – I see people looking out for us and ensuring we don't fade into history like a thief in the night.  In short, I see...  Immortality...

Okay, maybe a little too high on myself there...

SLA 3D Printer Project Log 11.5: I hope paint don't watch me dry...

A quick update of the progress of my Printer:

• Tallied up the parts needed and found I still had a great many detail parts to account for; frustrating, no?
• Also need to get the Resin Basin lased - Is there some kind of standard way to mark a part of a drawing to indicate that it's scrap?  That would save the end user having to adjust for various laser cutters as he shops around the suppliers.

I managed to run a test using spray paint on the RAMPS mount, it's just standard DIY spray paint from Wickes (Satin White, looks glossier than I had imagined, then again I really ought to use primer):

Not too bad, but still got a lot to learn about spray painting.

It seems my overzealous application has soaked into the wood - a good start to preventing water ingress, but probably indicates that the two 400ml cans I bought will run out before the job is done.

I began the experiment with a teaspoon-full of tap water in the centre of the painted face:

It's being supported on top, a good start!

The reason I want to paint the panels is simple - I may not have the luxury of storing this printer in my house, which means it must either be placed in a garden shed or in storage, neither of which can be guaranteed to be completely dry.  Upon examining the part 1 hour and 30 mins later (3x the duration I had planned!), I was quite pleased to see this:

Same size, same shape - no water ingress!

As for constructing the frame itself, I plan to have assembled the Z Carriage, External Panels and Resin Basin before I dive into it, since their dimensions cannot be certain until they are fully assembled; using thread-lock is a must with the frame (it bears the weight, and we *cannot* allow the projector to be vibrated out of alignment), and I'd rather make things fit before the thread-lock sets.

Stay Experimental.

SLA 3D Printer Project Log 11: Lasing on a sunny afternoon...

Exciting news on the making front:  my Laser Cuts have arrived!  Before I've even finished cutting my Extrusions (I'm a horrendous procrastinator), CutLaserCut of London have furnished me with 6mm Plywood Panels for the exterior; These parts have an almost psychotic precision to them - I drew these in Sketchup which draws Circles as slightly smooth polygons, and every face was sharply defined on even the smallest curves, running my finger over them felt like a D20 would if you felt it with your foot.

I reckon on a little show 'n' tell:

Clockwise from left:  Rear panel with PC Case and 180mm fan in place, Top Panel, Bottom Panel.

As you can see I stuck to fairly simple shapes for this, with lots of holes for the M4 bolts holding the panels on.

Left:  Front Panel; Right:  Both Side Panels (they're identical)

The Oblong bevelled holes are for the access panels which are to be made out of Fluorescent Acrylic (these absorb UV light, cuts out light pollution from external sources).

Another shot of the rear panel with rear-mounted equipment in place.

Of course, the fans will be internal and behind fan grilles once I assemble this thing, but the PC will remain external for access and cooling.

Misc Accessories, parts which make up things like the build bed (bottom left) and the Z carriage upper plate (top right).

The only problem I can see so far is the fact that many of the panels have warped, as can be expected for such thin plywood panels of this size.  It doesn't matter for parts other than the Z Carriage and possibly the Top Vent Cover (the rectangular plate with curved corners and all the cut-outs in), so I think I'll use Aluminium Angle bolted to the Carriage to ensure a level fixture for the Bearings and Threaded Rods driving the Z Carriage up and down.

"Why not use more plywood, or just glue on some Straight Scrap wood?"  Wood has a fantastic Strength-Weight ratio, especially Plywood, but ultimately while it can be very stiff, it is not that strong overall; The parts I use to stiffen can also warp which takes me back to my original problem.

Whew, an enticing delivery indeed, a glimpse into the future form of my Printer; just to end it on a high note, let us view this ultra-cute image of my bodged projector perched on it's mounting plate:

So far I've logged more hours watching youtube videos on this thing than it would be used for roughly 100 small prints!

Stay Industrious.

SLA 3D Printer Project Log 10.5: 12 hours in a single shift? Count me in!

Late July?  What kind of excuse do you suspect I have this time?  I mean, 2.3 months, okay, that's not too bad, I thought it was at least 6 months for some reason.  There is a reason why the Tawe TMD blog has suddenly come back to life (hopefully not to fall dead again), and bizarrely it has nothing to do with model trains.

Let me introduce you to my working life; Before recently I was working a standard 5-day 8-hour week, "Big Deal!" you crow, "I manage to model!", trouble is that I'm quite the lazy git - me and go-getting just don't gel.  The company I work at (not named because legal blah) has been quite demanding with regards to overtime, I usually ended up doing 4 hours on Sunday; Add that to my gym session, an essential as I approach that dreaded mid-twenties period where you apparently balloon up without warning, and I am left with only one free day - Saturday.

Now, if some of those who know me suggest "well, if you let go of them train trips you keep taking all the goddamn time..." they'd have an irritatingly condescending point; I take these trips as though I'd go mental if I stop, I don't even know how I can afford anything else sometimes.

This brings me neatly to 4 on 4 off - this is where you take 4 12-hour days in succession in exchange for 4 consecutive free days.  A quick cliff-note version of my verdict:  Super!  The 12 hour days might sound arduous to some, and they are when there's nothing to do and you are basically being paid not to have fun at home, but overall they only feel marginally longer than 8 hours due to sheer momentum.

"But don't you feel super-knackered afterwards?"  That is true, when I cycle home I feel as though I'm being fuelled by raw desire to slump into bed, but that was also true of 8 hour days and even of 4 hour days when I worked retail or even as a gardener (Sewer Maintenance looks like an adventure compared to those two).  You just exist in a state of semi-cryostasis in which you can only find energy to procrastinate.

Is this a SLA log or not?  Content, dammit!

Yep, this is instalment 10.5 simply because I've not got much new to announce, just a milestone and a minor announcement, really.

I've begun construction!

What industry and a wrecked elbow looks like.

Looks like a sizeable pile of parts, no?  Tell you the truth, I have nearly 15 metres worth of extrusion to cut!  Its all spread out across 11 1.5m extrusions (a decision I rather regret now), and initially I used a junior hacksaw i.e:  a one way ticket to both carpal tunnel syndrome and a dislocated elbow.  Get an Angle Grinder on the Case!

Fittings are yet to arrive, as I've ordered 75 Corner Braces alone, it's not easy for Proto-Pic to fulfil such demands as mine on a dime.  Overall, I seem to be well on my way, a fantastic feeling once you've cleared that dreadful middle part of any project, that pit in the bell curve where energy goes to die.

Minor Announcement?  Oh yeah, I plan to make a free build guide for anyone wishing to make their own machine, I believe that I've already said that the .skp file and .STLs will also be open source.  This, if anything, is a dry run for how I take to writing future build guides and possibly eBooks in future.  I dunno what those'll be about yet, probably train trips.

Stay Superb.

SLA 3D Printer Project Log 10: It's Extrusive!

Aluminium Extrusions...  How could I have missed you so?  Such a simple way to build up frames, especially for prototypes; here I was about to spend £400 on laser cutting plywood into a rigid frame, as well as £160 for 3D Printed parts!

Advertising my stupidity is a good way to begin a post, no?  Just to prove the opposite, I'll divulge to you what I've got in mind thus far:

A fairly basic crate :)

As can probably be seen in this image alone, Aluminium Extrusions are essentially the Lego of the garage hacker, allowing rapid construction of non-standard frames and sub-assemblies by way of nuts which fit into grooves in aluminium bars, with bolts then holding it all together.  Compared to the previous laser-cut plywood design...  Actually, why not invoke an excuse to use bullet points rather than actually write?

Goods

• Rapid addition of any newly-required features
• The Projector Crane can be an integral part of the frame for additional strength
• Plywood parts can be cut by hand - superb precision is no longer needed since it is automatically attained by a precision-manufactured metal framework

Bads

• If a casing is used (as you can see, it is), you may have trouble upgrading to a bigger projector
• Design is largely limited to right-angles

Not much on the bad side, eh?  Pity it's far from finished - the build-bed requires extensive re-working since I plan to only use laser-cutting for the Resin Basin (this part needs to be made so well you'd think I cast it whole) and I need to model all the brackets I'll need to assemble this thing.  All in all, not bad for a rediscovery made possible by a discussion with a colleague at work :)

Until we meet again...

How to reduce STL errors: Get your 3D Printed items error free for Shapeways

We've all been here, red faces flagging up all over our models thwarting our attempts to produce consistently printable models.  Just to emphasize how annoying this can get, here is a screenshot of my Caswell Flats STL just after export from Google Sketchup:

Just you wait until you introduce curves into the model...

See those red areas?  Those are degenerate faces, and they can do much more besides making the model unsightly, up to and including causing a non-manifold model - all 3D printers require the model to be "watertight" or manifold to print, that means there must be one consistent shell.

Having gained much practice in handling STL files, usually through frustration, I thought I'd put it to use by outlining these three tips to flush out the degenerates and, better yet, prevent them from happening in the first place:

1.  Get Netfabb

Let's face it, computers being computers, no CAD program is ever going to produce a perfectly error-free *and* a detailed, high-resolution model first time (even if such a program did exist, the cost would be horrendous); enter Netfabb - a slick, attractive application that makes light work of banishing the reds.  The Basic version is free to download and use with no time limits, and it fixes most errors with automatic ease; it is, however, limited to the most basic of STL sins and cannot, for instance, Wrap Part Surface which reconstructs the shell of a model to close up the holes.  For £200 you can upgrade to Netfabb Private, which allows access to all the tools you'll ever need to fix STLs (I personally cannot comment on their effectiveness since I only use basic, still, one for the future investments list).  There is a hideously-priced Professional version costing 1500 Euros, which I'd only suggest if an automatic nesting algorithm sounds vital to you.

2.  Reduce the resolution of your models before exporting to STL

Not a sure-fire fix, but one that can get your models from 'RED ALERT!' to 'that'll do'.  Resolution pops up in many different ways, for instance Creo Elements Direct (which I strongly suggest you get if you want to model curves) features an 'Facet Accuracy' setting, accessed via Right-Clicking the Part, selecting Part Properties, then the Facets tab; This will give the option to set either the minimum distance or angle the model will be permitted to render.  This is the result if I go for the insane resolution of 0.5 degrees:

Aside from bringing my new AMD R9 290 Graphics Card to it's knees, this is what 5244010 triangles and 250mb of Chassis looks like.

So you're thinking it's not too bad, except that 73 shells and 144 holes are produced...  Netfabb ran out of memory trying to fix it (silence...).

Let's go down a gear to 1 Degree and see how it is:

Errors around the Pinpoint bearing holes are reduced :)

The repair I tried in Netfabb Basic did little if anything to reduce those lines, although this exercise illustrates a point:  Reducing the resolution not only rids you of reds, but it also reduces strain on your Graphics Card as it renders the model and it makes smaller files with the 1 Degree file being 67.6mb.

3.  (Sketchup Users) Use Solid Inspector

Sketchup hit the spot for many modellers when it introduced it's extension warehouse, myself included - trawling the internet for obscure, often poorly-optimized plugins is now banished to the past along with floppy disks and those chirpy modem things.  One of these plugins to come to our rescue is Solid Inspector, a straightforward function which highlights any issues with Sketchup models by circling surplus lines with orange and holes with red:

This is a rather severe example, but you can hardly blame us when you take the Tumblehome into account.

That was the body of No. 394 of the Chesham set of Metropolitan Bogie Carriages, at which me and Matt Wickham at Bluebell Model Railway (click here for some video of the carriages running) have been beavering away on for some time; Admittedly finding the actual rogue lines and holes is still tricky since the circles don't always scale to your viewport, but as a general indicator it's a godsend which can mean the difference between printing and self-inflicted pain.

The Takeaway:  3D Printing, not 3D Perplexity

There may well be other methods I have failed to mention, but I can sum this post up thus:  Don't rely on your eyes to find faults.  A CAD model, unlike your hands, CNC machines and even reality, can scale down into infinitude, theoretically to the Planck Length and below; that said, god help you if you want to zoom back out again!

SLA 3D Printer Project Log 9: Call me tight-fisted...

Been almost a god-forsaken month since I last posted on this!  Usual excuses apply - work, tiredness and other priorities.  Regardless of this, I am proud to present a completed model for the SLA 3D Printer!

Mostly Plywood construction to keep 3D Printing costs in check.

As much as I'm tempted to excuse the lack of RAMPs Board and some of the hardware (nuts, for instance), the simple fact is that I couldn't be bothered...

This is where the action is - looking down on the print bed with the beam set to 12.8 x 8.0 cm build area.

With this simple design in mind, let me take you through the DXF files for the laser cutting, which should hopefully let you know just how much goes into things like this:

25346.8mm of lasering goes into the 6mm ply parts ALONE.

Looks refreshingly simpler, but these 12mm ply parts still need 25260.6mm of cutting.

Finally, 12mm Cast Acrylic makes up the basin with a mere 8290.95mm of cuts.

Some of you may be thinking "Gee, that's sure to be expensive with all those finger joints and details" - how does £400 inc VAT sound?  Sure, it's a major expense, but would *you* consider doing this by hand?  All I need to do is persuade my ego to let go of that 4K monitor for just a few more months (not gonna happen ;) )

If you've read this post over at the life blog (to hell with re-writing the name here, that pubescent cacophony of letters needs to change), you may notice that I am aiming for change in the coming months not just with my blogs but my whole life - things are getting quite heavy for me and I need to re-tool.  The basic gist is that I am trying to do too much and it's driving me insane to the point where I just dive into PC Gaming and get nothing done, so a few things may have to come and go.  This project is here to stay (why not cut out the middleman for minor detail/operation changes?), but I'm looking into other avenues to try my hand that may eventually make me a decent living if I can pull it off correctly.

Finally, all my blogging is now on here, (pubescent jumble blog) is now mothballed.  Hope to see grasshopper-minded adventures on a much grander scale once this bridge is crossed.

Stay Industrious...