discussion FDM PLA 3D printing - with a model making inclination

[Dave Ward]

glad to see it worked ,Dave. I guess the thin walls is a consequence of scaling down?
Something to watch

Yes, not something you usually have to worry about! I was wondering what sort of machiner could print this in it's original scale, but I realised that all the pieces are about 200mm long max. - so it could be printed on a standard Ender style printer, but a train at 1/22,5 is a bit big! ( about 800mm long! )
Dave

 

[Gary MacKenzie]

Yes, not something you usually have to worry about! I was wondering what sort of machiner could print this in it's original scale, but I realised that all the pieces are about 200mm long max. - so it could be printed on a standard Ender style printer, but a train at 1/22,5 is a bit big! ( about 800mm long! )
Dave

If the model isn't higher than the build area height you can print very long items with conveyor belt printers like the ones @ https://3dwithus.com/conveyor-belt-3d-printers

The cosplay/ props people use them for swords etc.

 

[Dave Ward]

This may be wishful thinking, but I'mm attempting to print this

Foden Type C Steam Wagon
It's not all in one piece, the roof & wheels are separate - I've blown it up to 1/35 - two failures already, if the one that is on the bed now fails, then I'll forget about it. I was looking for a Scammell Scarab, but the only ones I could find just don't look right. I've only ever seen the old Airfix/Dapol 1/76 Scarab as a model, and I thought one in 1/35 would look very different from the usual 4 wheelers!
Dave

 

[Gary MacKenzie]

https://www.cgtrader.com/free-3d-mo...ail-scammell-scarab-no-1-dummy-old-steam-days << free , might be ok
https://www.printables.com/model/477475-scaleprint-scammell-nightman-00ho-scale >> free on printables , but a different nose to scarab
https://www.printables.com/model/295661-oit-scammell-mechanical-horse-1-148 >>> mechanical horse version

 

[Dave Ward]

https://www.cgtrader.com/free-3d-mo...ail-scammell-scarab-no-1-dummy-old-steam-days << free , might be ok
https://www.printables.com/model/477475-scaleprint-scammell-nightman-00ho-scale >> free on printables , but a different nose to scarab
https://www.printables.com/model/295661-oit-scammell-mechanical-horse-1-148 >>> mechanical horse version

Thanks for that, Gary - I'd seen this one before - first on your list, the Scarab I'm looking for

When you get it to 1/35, there's no real detail - even the windows aren't marked..................
The other two, well, Im not familiar with these, are they earlier, or later than the curved version?

I didn't know that they were also called 'mechanical horse', or 'nightman', so that may be another avenue of search.
Cheers
Dave

 

[Gary MacKenzie]

The problem with a lot of the 3d stuff is it can be printed, but maybe shouldn't be due to low polygon counts in the designs.
They tend to be made for use in games , where a skin is wrapped round the frame and creates the details

I remember the yellow/orange painted 3 wheeler tractor and a trailer behind it in Edinburgh and Newcastle stations in the very early 70's. but at least one had no cab on it.

 

[Tim Marlow]

Mechanical horse was an early designation for them, but I thought that was the version around in the days of the big four railway company (pre BR) days, superseded later by the scarab. Never heard them called “nightman” though, that’s a new one on me. Seem to remember pictures of them cabless, but can’t find any on line so that might be my imagination.

 

[Gary MacKenzie]

One version ,​

Conveyancer-Scott unknown British Railways Electric Elevating Platform Truck​

=========================================================================

This states there were 3 wheel units that replaced the item ( d ) , but no pictures of the replacements


Electrically powered trolleys were invented at a railway station in Philadelphia (USA) in 1906 and arrived in Britain shortly before the First World War. These would not be seen on a branch line platform but all the major passenger stations and larger goods depots had them. Early types were often rather complicated looking machines (see Materials Handling - Introduction) but Fig___D shows a type in common use on the railways, docks and in industry from the mid 1930's to the end of the 1960's. The driver's left foot is raised as he has taken it of the 'dead man's pedal', cutting power to the motor and applying the brake. This type was taken out of service in the 1970's because of health and safety legislation. They were replaced by small three wheeled or later four wheel tractors with a seat and steering wheel, first seen in the 1930's but mainly confined to larger stations.


The closest I can find that I ''remember''

https://www.modelrailwayscenes.com/products/oo-scale-platform-truck-tractor-1-pack

 

[Tim Marlow]

Your first photo is the type I remember from pictures Gary. The second type developed into British Railway Universal Trolley Equipment (BRUTE) in the sixties. They were everywhere up until the eighties when loss of parcels and newspaper traffic made them redundant.
The trolleys were like this


They were pulled by these


A lesser known use was as an invaluable place to base yourself when train spotting. They were just the right height to sit in comfortably and held your kit while you were at the station.

 

[Gary MacKenzie]

Your first photo is the type I remember from pictures Gary. The second type developed into British Railway Universal Trolley Equipment (BRUTE) in the sixties. They were everywhere up until the eighties when loss of parcels and newspaper traffic made them redundant.
The trolleys were like this


They were pulled by these


A lesser known use was as an invaluable place to base yourself when train spotting. They were just the right height to sit in comfortably and held your kit while you were at the station.

I remember a variation on the last pic you placed where the shield up front was more like a motorbike windshield curved design, but as I said either Edinburgh Waverley or Newcastle , and usually hauling mail sacks and a few larger baggage items

 

[Dave Ward]

After the Merchant Navy, eventually I ended up at Lister-Petter, in South Gloucestershire. This was an odd factory in that it was about 2 miles long, but nowhere more than 200yds wide,sitting in the bottom of a valley. Moving stuff around was a major problem - but it was solved by using something called a Lister Auto-Truck

This consisted of a twin cylinder diesel mounted in a ring, which swivelled the whole engine around for steering, with a single driven wheel underneath.

Even a passenger version - Not at Listers, I couldn't find a picture!
These were made from the 30s to the 70s in large numbers including versions that ran on narrow gauge rails, had hydraulic lift platforms, used as tractors, in the military, railways & generally light transport. They'd been out of production for about ten years, when I went to work at L-P, and they were still in use, but gradually dying of old age and overwork, being replaced by fork lifts! The Auto-Truck had become non street legal, which was why production stopped. There are still a lot around, maintaied by enthusiasts
The first time I saw these odd little machines was as a kid, on holiday. Quite a few seaside resorts used these on their promenades to move stacks of deckchairs etc. I can remember them at Bournemouth and Bridlington!
Dave

 

[Tim Marlow]

Nice picture Dave. The rail versions were similar to the WW1 simplexes I believe.

 

[Dave Ward]

I've been revisiting some of my earlier models, to see if different settinfs, especially in the model supports can make a difference. In some it has, others not. It has allowed me to retry a model, which I never managed to complete. due to varoius problems.
This is the Dingyuan - a Chinese 1881 Ironclad battlwship

Apart from the two masts, it's one single print - I have lost two pairs of fragile boat davits, but easily replaced.
This is blown up to 1/350 from a 1/700 free file from Thingiverse. It took about 10 hours to print. One major thing I've taken to heart is that printing at slow speed works best. I've no doubt that later printers can do this in probably half the time, but I set this running overnight, so time isn't a factor. There are details missing, the designer has separate generic files for the ships' boats - they apply to others of the models this guy produces. I've printed some of them before, but there's one I want to have a go at - although the hull will have to be printed in two pieces, as it's too long for the build plate in 1/350
Dave

 

[Dave Ward]

In 1/350, the French Armoured Cruiser ' Gueydon' of 1903

The hull was printed in 2 pieces, the funnels, turrets & bridge being separate parts, The boats & davits have yet to be added. The only casualty was the spotting top on the bridge - it broke off on clean up & the carpet monster got it. I'll print up a replacement.............
This is a 1/700 print of French Battleship 'Charles Martel' of 1897

Single piece print - blown up, the model is about 20mm to big to print in 1/350 on my build plate. I've split it in two - but I think the detail may be a bit too heavy in the larger scale, we will see.
These are all printred using the organic ( tree ) support function in PrusaSlcer 2.6.1 & using my standard Geeetech PLA filament in silver
Dave

 

[Dave Ward]

It's very easy to make mistakes - I'd split a model in two to fit it on the build plate, sliced them & then printed............................ first one was OK, took about 7 hours to print - I decided to print the other part overnight. As is usual, I watch the first few layers be printed, to make sure it sticks & the filament is running smoothly. before turning in. Next morning, print is finished, but looks odd! I try the two halves together.........................one is bigger than the other! A scratch of the head & a few curses! After a brief ponder I realised that I'd fouled up my carefully calculated scaling factor - I'd even written it down! For one I'd used 87% ( correct ), but for the other 78% ( NOT correct ) - all too easy to dyslex the numbers......................
Another model too big to print in 1/350 is the Charles Martel ( previous post ), so the model was split & the larger parrt printed overnight - this took 13 hours - this is the result, stiill on the build plate

This is using the organic ( tree ) supports - it looks a complete mess, but a carefull clean up with sprue cutter, pliers & dental probes will reveal the model beneath. This is the aft part - the front part will follow!
You have to decide where to split the model, the obvious place would be in the middle, but this would coincide with the side turrets & give a really nasty joint line, so I moved it forward to a cleaner area, so now its not two halves, but a third, and two thirds..
Hopefully tomorrow, I'll have the two bits prepared, and the Charles Martel will be revealed in all its' ugliness!
Dave

 

[Dave Ward]

A modification that I made to my printer was to replace the build plate with a PEI spring steel plate. This improves the.print sticking to the bed & aids removing a finished print. There are two sorts, those that are magnetic & those that are held on by clips. The magenitic plates are over twice the price over the clip sort. Naturally I went for the cheaper! It has a disadvantage, I find - unless you place the clips carefully, there is a possibliity that the nozzle can come into contact with them. This happened on my print of the Charles Martel. it resulted in a slight chip, or nick in the nozzle, so that the filament came out an angle, not at 90 degrees. I watched the first level go down & stick to the plate - it seemed to be OK, so I left it. Next morning, it had finished, but looked terrible, the layers didn't stick together properly - it felt like a sponge!
It tool quite a while to figure this out, but a new nozzle was the solution. I managed this for the first time without burning my fingers. After a nozzle change, the bed has to be re-levelled -not a problem, just takes time. The printer is now happilly cuckling to itself.
The nozzles are brass, and they do wear out, they are cheap, and can be considered a consumable, I do have a small box of spares, like nozzles, drive belts, fans - all simple replacement parts. I get them from China, where they are all made, it can take a couple of weeks to get them, hence my spares. You can get them a lot faster in the UK, but they are still the same Chinese made parts at a substantial premium!
Dave

 

[Dave Ward]

The aft part of the Charles Martel cleaned up nicely................

.........but revealed a problem. .stl files are a large mesh of triangles - the larger the number of triangles, the better the definition, but the larger the file. if you have too many triangles, the slicer programme won't work. The Charles Martel was designed in 1/700, when I blow it up to 1/350, the size increases, but the number of triangles stays the same. The surface definition is the same as at 1/700. When you look carefully at a round obfect ( like the turret ), it's actually a polyhedron, with facets
Nothing you can do about this - printing at it's original scale is fine, but there is a limit on how far you can blow things up. Angular objects, no problem. Curves are the limiting factor.
Front part of the Martel, with supports still attached - they cleaned up nicely
Dry assembly of the two parts, the jointiiing faces need to be sanded smooth

This battleship was completed just 3 years before HMS Dreadnought made it & all its sisters obsolete............
Disappointed with the final result - things don't always turn out the way you thought!
Dave

 

[Gary MacKenzie]

Dave , this may be of interest to you

https://www.amazon.co.uk/dp/B0BT9HNN71

Black Friday Deals : eSUN PLA Filament 1.75mm, 3D Printer Filament (7 colours available)​

 

[Jim R]

This is using the organic ( tree ) supports - it looks a complete mess,

I looked at the photo before reading this. It really looks weird. Cleaned up it looks good though.

 

[Dave Ward]

Dave , this may be of interest to you

https://www.amazon.co.uk/dp/B0BT9HNN71

Black Friday Deals : eSUN PLA Filament 1.75mm, 3D Printer Filament (7 colours available)​

I'm not a Amazon Prime member, so the price would be £17.99 + p&p - I get my Geeetech filament from an Ebay shop at £12.99 delivered, although my favourite silver filament seems to have vanished - I'm now going to use black. I'm using the same brand, hoping that this reduces any tweaks I may have to make, with the change
Dave