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FDM PLA 3D printing - with a model making inclination

Had a problem this morning - the print wouldn't stick to the build plate on my big Anet printer - I thought it was a levelling problem, but no, whatever I did the filament wouldn't stick & created plastic brillo pads! Thought it may be the filament, so I opened a new shrink wrapped spool of PLA. Whilst I was loading this & purging the old filament, I noticed that when the filament came out of the nozzle, instead of dropping as a thin thread, it came out & curled round the side of the nozzle. I tried cleaning it, but eventually had to change the nozzle - a tricky procedure, as it has to be done with it hot - about 230C - bad enough getting the old one out, but putting in a new one! Despite being careful I still managed to get a few burnt fingers. I obviously damaged the original nozzle somehow, and it wasn't pushing filament out correctly. I'm mystified, as it was printing OK yesterday, and the only thing I'd done to the printer, other than turn it on was change the micro-sd card!
Dave
All I can assume is that the print head collided with the print surface and damaged the side of the nozzle.
Print nozzles do also just fail, sometimes spectacularly, and the filament that was still in it hid the damage until it heated back up again.
 
Thread owner
All I can assume is that the print head collided with the print surface and damaged the side of the nozzle.
Print nozzles do also just fail, sometimes spectacularly, and the filament that was still in it hid the damage until it heated back up again.
I've looked at the nozzle I removed, and I can't see anything wrong with it, bit any irregularities in a 0.4mm hole would be difficult to spot. Luckily brass nozzles are cheap, so it's not a problem. If I was using other filaments like Nylon, brass nozzles would wear out pretty quickly & you would have to use steel, or even ruby-lined nozzles!
Dave
 
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I've been pushing the printers, to find their limits on quality & how small I can actually print - this has meant quite a lot of failures, and a lot of time spent finding that out!
Two things that I found out - never buy any more black filament! Printing black on a black building plate makes it very difficult to see what is actually going on - prices are the same for the basic colours, so anything but black. Another thing is using the whole of the build plate. Invariably, when you open the model in the software slicer, it appears in the centre of the plate, that's fine, but printing constantly in the same place causes the surface to wear. At first, my prints stuck well to the build plate, but gradually they began to fail & I had to use a glue pen ( like Pritt, or Elmers ), I put it down to the wear in the centre portion of the plate - now I'm moving the prints around on the build plate, in all quadrants to even out the wear. This wouldn't happen with a spring steel build plate - but my flexible magnetic bed does wear. - I'll have to get another as a spare!
I'm afraid the USS St Louis is going on hold. The model itself is too big & unwieldy. I find that there are still around 100 parts that I haven't printed & there are multiples of some parts. I should have scaled it down to 1/350, but that would still leave the problem of all those parts. One of those things that I didn't really think it through! The novelty of the printer carried me away. I'm concentrating on 1/350 models from now on!
Dave
 
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I think I've reached the limits as far as the Anet A6 goes - I'm printing some 1/350 bits - I thought I may have trouble with these bits, but no,
DSCF4273.JPG
The bottom part s the lifeboat support structure I didn't think the lattice would print cleanly.
I then tried to print the 'cranes' - I knew that it was pushing it- I tried several orientations, but settled on which there was the least supports. It actually printed very well - but removing the supports cleanly was not possible
DSCF4274.JPG
Top is how it comes off the print, with the supports. The lower 3 bits are the result of trying to remove the supports carefully! They're only simple posts, so scratching them won't be a problem. I've turned to the Monoprice & set it to try and print them, on the highest settings - not really expecting them to be much better!
The problem is not the printing, it's the clean up - with thin delicate parts, it's not really feasible. The PLA is tough, it's not brittle, but resilient, you have to tear, or cut the supports, which ends up with broken parts. You really have to look at the models & try them in various orientations on the build plate to see which has the best chance of succeeding, not something that is immediately
obvious!
Dave
 
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I've learned that the slower you print, the better the results generally are. This is especially true on the Anet A6 printer - the Monoprice is pretty slow anyway!
All this means is that you have to wait longer for a print, but that isn't always viable.
I found a 1/600 model of Fort Drum
Fort Drum.jpg
An island in Manila Bay, Philippines concreted over by the US, & armed with battleship turrets!
As the model is, scaled down to 1/700, the printing time for the 'hull' is about a day and a half! I'm looking into hollowing it out, that leaves just a shell, but that has problems of its' own, very much a WIP!
I've noticed that the price of my PLA filament is climbing - my first 1 kg spools were £10.99 delivered, but that has now gone up to £11.99 - it's still very cheap for what you can do with 330m of filament!
Dave
 
Thread owner
Exploring further into models that can be downloaded - I came across this
MT-T.jpg
Russian MT-T multi purpose tractor in 1/35 ( I think ) This will need a bit of investigation - I'm hoping this uses a standard T-72/T-80 track link. The wheels I could print, but nearly 200 track links isn't going to happen! The model itself is broken down into printable sizes pieces, without any splitting, so it's a possible!
Dave
 
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A printer free day - one, or other, or both printers have been in use every day for the past two months, or so!
A bit of investigation, and I've found that the MT-T ( above ) was based on the T-64 transmission & running gear, so tracks from that should fit!
Here's a model I printed out & primed
DSCF4299.JPGDSCF4298.JPG
Bob Semple tank - the only tanks ( 3 ) produced in New Zealand.............. The model was a minor mistake - I thought it was in 1/72 scale, but it actually is in 28mm (1/56 ).
The next model is very simple - only 3 parts - the hull & turret were absolutely no problem, but I had to have two goes at the superstructure
DSCF4295.JPGDSCF4297.JPG I think this has turned out to be the best print so far.....................
It's the 1/350 French Coastal Defence Ship 'Fulminant' launched 1877- served until 1908.
A lot of the models I find are for SLA resin printing, although it doesn't always say. Some are immediately apparent, but this was a borderline case. You have to assess each one! My first superstructure print was terrible, so I tweaked a few settings, and most importantly slowed the print down. Considering all the bits. like the boat davits etc, it turned out very well ( about 4 hours on the Anet printer ). It took quite a bit of clean up, removing the supports, but they came off cleanly. It's only when you prime can you see how the print really is
Dave
 
I think this has turned out to be the best print so far..............
I was just going to say that your prints are getting better and better. I suppose you refine your approach as you get more experienced.
 
Thread owner
I was just going to say that your prints are getting better and better. I suppose you refine your approach as you get more experienced.
I think a lot is accepting that certain models are not suitable for my printer & rejecting them, they never get to the stage of refining! It takes a lot of time, tinkering and tweaking to improve prints, and I can understand that it's not everybody that has the time & patience to do this.
I had the box containing the printer bits delivered on Jan. 5th, and the first print was done on Jan. 24th. I can say that it has been very rewarding - it is a very steep learning curve, and at times exasperating - but now I think I've got the basics in hand. It would be quite frightening to total up the hours I've spent on this, just as well I'm retired..................
Dave
 
Thread owner
Whilst printing the boats out for the Jaureghiberry - I did a bit of investigation for the MT-T, and I think I can source tracks for this beast, if not the wheels & sprockets.
I've been preparing the .gcode files, these are the instructions to the printer - what temperature for nozzle, build plate, speed & all the commands for X,Y & Z-axis movements. It sounds complicated, but the slicer software does all this.
This is one side of the hull, on the build plate - it's just about the largest I would want to print, & only just fits on the diagonal.................
side.jpg
This is using PrusaSlicer software, most slicer programs are very similar.
I tried various orientations, to see which was best for supports. The supports are generated automatically, and allow printing of overhanging parts.
side support.jpg
Orange is the actual part, green is the support material. this will hopefully just crack away after printing ( with luck ).
With all the settings I have chosen, this will take over ten hours to print, so I'm going to set this going overnight - I just hope that in the morning I have a finished print & not a pile of plastic wool!
Dave
 
Thread owner
This is what I found on the build plate this morning
DSCF4301.JPG
Looks similar!
After a long time, cutting, prising twisting - I got all the supports off - and primed to see what it looks like:
DSCF4302.JPG
Not too bad - the rough bits will be hidden behind the road wheels - the underside is very poor, so I won''t show it..............
I/ve been digging in the stash & found some suitable tracks, also sprockets & idlers, that may fit. The tracks are actually T-72 bits. The MT-T was based on the T-64 running gear, as was the T-72, so I'm using a bit of licence with the tracks. The MT-T is substantially longer than the T-64/72,so I need more than one set. I'm cannibalising a part-finished Zvezda T-72 & taking bits from an Italeri boxing ( it's a pretty poor kit anyway ). I'll be printing out the other side overnight. Then I'll have to change filament - blue next!
I'll be starting a build log on the MT-T soon..................
Dave
 
This is what I found on the build plate this morning

Looks similar!
After a long time, cutting, prising twisting - I got all the supports off - and primed to see what it looks like:

Not too bad - the rough bits will be hidden behind the road wheels - the underside is very poor, so I won''t show it..............
I/ve been digging in the stash & found some suitable tracks, also sprockets & idlers, that may fit. The tracks are actually T-72 bits. The MT-T was based on the T-64 running gear, as was the T-72, so I'm using a bit of licence with the tracks. The MT-T is substantially longer than the T-64/72,so I need more than one set. I'm cannibalising a part-finished Zvezda T-72 & taking bits from an Italeri boxing ( it's a pretty poor kit anyway ). I'll be printing out the other side overnight. Then I'll have to change filament - blue next!
I'll be starting a build log on the MT-T soon..................
Dave
Surprised you didn't build that on its back Dave, all the support would have been inside.
 
Thread owner
I changed the filament on the Anet - it should be quick and easy, but every time I do it, I disturb the Z-axis ( one side lower than the other ), and in consequence I have to go round & check the build plate levels. The printer is now muttering away, doing the cab for the MT-T. This is an important part, as it will be probably be the most visible part of the model - it's going to take about 8 hours to print. The new blue filament is much easier to see on the black build plate.
Looking for models on the internet, I'm consciously looking for models that don't have a plastic counterpart. If I wanted a Tiger, Sherman, Panther etc, there's loads available, but Meng, Takom, Tamiya and the others have covered these extensively So, it's the odd & obscure that I'm looking for - at times it's not obvious whether it was a real thing, or a a steampunk/fantasy. One of these is a crossover - the tank from ' Indiana Jones and the Last Crusade' !
Dave
 
I admire you fellas that can do this sort of stuff.Its the future of figure sculpts for many.Id love somebody to do some Sherman aerial pots for glacis plates to help with conversions.
Good work.
Richard
 
Thread owner
After 8 3/4 hours the cab has printed out............
DSCF4304.JPG

First thing tomorrow will be to remove the supports from the inside of the cab. Next part to print will be the load bed - essentially a large postcard sized flat plate!
FDM printing is one way forward, SLA printing ( UV curing resin ) has more potential, but has it's drawbacks - toxic resin & chemicals, nasty fumes, flammable liquids for post printing processing............... hopefully future developments will reduce these problems.
However FDM printing with PLA filament is a non-oil based process. PLA is a plant-derived & a sustainable product.
Dave
 
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