3 D Printing 16mm models

[Trevor Thompson]

Latest update on the bridge:

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Trevor

[Trevor Thompson]

It is beginning to look like a bridge! Progress to date:

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Trevor

[Trevor Thompson]

So the bridge is now finished. It printed out successfully without any significant issues. Only a few elements had to be redrawn.

I have purchased the plastic weld glue, and used it successfully, but I have found a mixture of acetone and waste plastic very successful when surfaces are not perfect fits. I think it results in a stronger joint. I fill a bottle with acetone and push offcuts of ABS into it, stopper tightly and shake. After a few hours it forms a paste which can be added to one part of a joint with a pin. I wouldn't use it on rolling stock where stray glue might damage detail, but on something like this bridge it has worked well.

A word about settings for printing. I have increased the extruder temperature 5 degrees above default, used 6 top layers, 4 bottom and side layers, and 20% infil using a honeycomb matrix. I also dispensed with the raft, and added a brim around the components. The resultant bridge is strong- I can pick it up in the middle and all of the cantilevered staircases remain firmly attached.

In total the whole bridge used 1.3 kg of filament.

So firstly two views of the bridge in place:

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and views of of the "supports" I have invented for each of the platforms rising up the retaining wall (which are not there in the prototype): These supports are not structural - in the model - but I think that something along these lines would have been necessary in full size.

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Just needs some paint. It will be fun painting that lot with an airbrush!

Trevor

[pandsrowe]

What a superb piece of construction, I must say that really looks the part. I am somewhat surprised that you are going to paint it as I think it looks pretty good as it stands, although that may be a trick of the camera and in real life it may be quite different.

[Trevor Thompson]

No - it does look as good as it appears in the photos.

It is just that the real one seems to have been either oak or larch - anyway it seems to have been bare wood which weathers gray. It must have been a very durable wood because it was built in the 1870's and lasted until 1933. I want to paint it in various wood colours with the grey dominant on the upper surfaces.

Thanks for the kind comment!

Trevor

[ge_rik]

That does look impressive and sounds it with 1.3kg of filament. Wow!
I hadn't realised that PLA is biodegradable until recently, whereas ABS isn't. Are you intending to leave the footbridge outside all the time?

Rik

[philipy]

I hadn't realised that PLA is biodegradable until recently, whereas ABS isn't. Are you intending to leave the footbridge outside all the time?

PLA is allegedly biodegradable, which is why I switched to ABS after initial prints, but then I changed back to PLA subsequently, and I've had no problems with my PLA prints that have been outside continuously for 3years. I did have a door warp, but it is in the full glare of the afternoon summer sun and wasn't glued to the structure all the way round. I think the problem was more heat warping than biodegrading.

[Trevor Thompson]

Yes I am planning to leave it outside all the time. I have some space indoors for winter storage, and perhaps in the future will have more. However there is a limit to how many large structures you can find room for.

The engineering workshop is a wooden model so that will have to go indoors in the winter. The durability of ABS is part of my thought process. I do hope to leave the ABS buildings outside all of the time.

I have just started to print the water tank, and I have prepared the CAD files for the wooden fencing. and am about to design a model of the original station masters house (which is still there).

More on those to follow.

Trevor

[Trevor Thompson]

Here is the CAD drawing for the water tower and tank. The plinth is a stone plinth - which seems solid from the photos. I have based on photographs of the one at Tan-y Bwilch prior to preservation:

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And the tank printed out. Each side took 3 hours to print, and the bottom 4 hours. It is watertight:

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The plinth is printing out - and each side takes 4 hours. It will be tomorrow evening before it is completed. I am planning to add the stone detail using one of those stencils, and grey floor tile grout.

Trevor

[philipy]

That tank looks very nice Trevor. I've been thinking I ought to provide watering facilities on mine but never seem to get around to it. Perhaps you've inspired me!

The plinth is printing out - and each side takes 4 hours. It will be tomorrow evening before it is completed. I am planning to add the stone detail using one of those stencils, and grey floor tile grout.

One of the first things I ever drew and printed was stone platform facing ( see https://gardenrails.org/viewtopic.php?f ... ng#p126127 ). The bright orange PLA came with the printer but was tamed by a couple of coats of 'Cotswold stone" effect dollshouse paint.
This is what it looked like when it first went outside:

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...and this morning after a couple of years permanently outside and 24 hours continuous rain:

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[ge_rik]

Looks great - presumably a coat of paint helps with durability.
A couple of questions. Did you need supports for the picket fencing or were the spaces between palings spanned OK by the printer? Are the parts on Thingiverse, by any chance?

Rik

[philipy]

Rik,
I printed the fence modules 2 together and face down without support. The posts are actually halved so they that just glue side by side subsequently.

In Cura, from the top:

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In Cura, from the bottom:

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No, none of them are on Thingiverse but if you want them I'll ping them over, no problem.
As well as the plain fence panels there are also angled ramp panels but they would probably be different angles to what you would need, and there are also individual posts so that a panel can be cut to fit a small space.
I suppose I could put them up, but back then I wasn't confident enough to expose myself(!!) and just never got into the habit.

EDITED to add: You've prodded me into now putting the fence panels and individual posts onto Thingiverse!!

[SimonWood]

Just catching up on this thread. So much inspiration here, having seen some of Trevor's models close up I was already eying a 3D printer as something to learn for a winter project (as if I need an additional one!) No doubt about it, I'm going to have to do it!

4415 looks fantastic Trevor, I love it.

The bridge is extraordinarily impressive - 1.3kg, how long did that take to print? It looks just the part, the modifications to take pedestrians up higher than the Tan-y-Bwlch prototype are very much of a piece!

[ge_rik]

... You've prodded me into now putting the fence panels and individual posts onto Thingiverse!!

Thanks Philip. It'll be a great addition. I'm sure it wouldn't take me long to draw them in TinkerCAD, but ..... well you know

Rik
PS. Liking the look of the water tower BTW. And that platform edging looks superb. So many ideas for printing.
PPS. I bought a battery operated working-light for the caravan - and have just drawn and printed a bracket so I can attach it to the ceiling. Amazing the uses a 3D printer can be put to!!

[Trevor Thompson]

Rik, Phil

If you want the files for the water tank you are welcome to the original Sketchip file or the stl files.

Rik, our motorhome habitation door catch broke and while it was under warranty I printed a replacement. I added a stainless plate to take the rotational stresses of pulling as you open the door. I never bothered with the warranty replacement because I think my part overcame the design fault in th eoriginal. As you say really useful bit of kit!

Trevor

[Trevor Thompson]

Just catching up on this thread. So much inspiration here, having seen some of Trevor's models close up I was already eying a 3D printer as something to learn for a winter project (as if I need an additional one!) No doubt about it, I'm going to have to do it!

4415 looks fantastic Trevor, I love it.

The bridge is extraordinarily impressive - 1.3kg, how long did that take to print? It looks just the part, the modifications to take pedestrians up higher than the Tan-y-Bwlch prototype are very much of a piece!

Thanks Simon, How long to print? - about a week almost non stop. Each of the floor sections took just over 4 hours, and most of the side pieces 3 and a bit hours. The stair cases were quicker as the sides were printed as separate lengths and the treads as individual treads. The sides incorporate slots to locate the treads.

[Trevor Thompson]

I have just finished priming the water tower. This is it so far:

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Quite a bit of painting to go!

Trevor

[ge_rik]

Not as ambitious as other posts on the thread, but I'm feeling pleased with the outcome. I decided some of my through stations needed another running-in board as, at the moment they have only one in the middle of the platform rather than one at each end. So, a quick bit of fiddling with TinkerCAD and here's the result:

Two yet to be printed

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.

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.
..... and one done so far....

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.
The stations with island platforms have double-sided nameboards.

Got plenty of other 3D projects in the pipeline

Rik

[Trevor Thompson]

Those name boards look vert crisp and clean. Very Nice.

Such an easy way to get the letter spacing correct - and the typeface constant! Well it is when you have worked out how to do it!

Trevor

[philipy]

Very nice Rik.
What are the dimensions of the BULKELEY board?