Model Engine Maker
Supporting => Additive Machining => Topic started by: Allen Smithee on December 26, 2020, 05:54:12 PM
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My Better Third bought me one of these (https://hobbyking.com/en_us/easythreed-x1-mini-fdm-portable-3d-printer-orange-uk-plug.html) for Xmas:
(https://cdn-global-hk.hobbyking.com/media/catalog/product/cache/1/image/660x415/17f82f742ffe127f42dca9de82fb58b1/1/-/1-_mg_1403-re_1.jpg)
A cheapo 3d printer (under £80) with an unheated bed - piece of complete junk, right? Well surprisingly I've found this machine is much better than you might expect, and with some care on the settings can actually produce good parts. There are various YouTube and website reviews of this machine and they focus on four main issues:
1. The bed is unheated
2. There is no part-cooling fan
3. It needs belt tensioners to remove play in the drives
4. The extruder is really only hot enough for PLA - you can print PETg with it but that really needs a heated bed, and the stronger plastics like ABS and Nylon need more heat.
It also has a very small print volume (100mm/4" cube) but that makes the whole machine very compact - it easily fits on the desk in my study, and can be just put on the bookshelf when not in use. But I'm getting ahead of myself.
Unlike most 3d printers this one comes almost completely assembled - no hours of trying to interpret chenglish instructions and ambiguous diagrams to establish where screw #331 should be inserted, and none of the famous chinese cheese-head screws (made of real cheese). You just drop the vertical column into its slot (feeding the z-axis connector through a hole), connect the connector, clamp the column in place with two bolts and that's it ready to go.
I gave it the once-over and immediately noted two things - firstly the play in the print head is pretty minimal because it has cable tensioners fitted, and secondly it has a part-cooling fan and ducting incorporated into the head assembly. So it looks like the manufacturers have responded to some of the initial criticisms with upgrades (which is nice). The heated bed I'll talk about later, but the PLA limitation is just one you accept for the cost of this machine.
The bed has a flexible printing mat (think of a 4" square, 1/16" thick piece of the material they make fridge door magnets from) that sticks quite firmly to the print surface and seems like a neat idea. I have bought an aftermarket heated bed (I said more anon - patience is a virtue) but if I use that I won't be able to use this mat. I tried it without the heated bed first so I could see if was worth the effort.
The control unit has four buttons - a "home" button that moves the print nozzle to a datum height (but only height, not X/Y positions), a "+" button that fires up the extruder heater and primes it with filament, a "-" button that extracts the filament so you can switch to a different one, and a "start/stop" button which (believe it or not) starts, pauses and stops the print. Each button lights or flashes its symbol to tell you things while they are in use. On the side of the controller there's the DC socket for the power supply, a type-A USB socket which they say is for "future use" and a slot for the micro-SD card containing the file to be printed.
In the box is a USB micro-SD card reader with a card in it. This card comes supplied with some software, the manual and a couple of sample files on it. I couldn't get the supplied software to install, but that didn't really matter because there's better software freely available on the interweb. For those that don't know, 3d printers need one or both of two kinds of software. First there's some kind of 3d CAD software to create the 3d designs in (usually) a format called "Standard Tessellation Language (STL)" - if you're only going to make parts designed by others you don't need this, but I use SolidWorks. Second is what's called a "Slicer", which is a bit of software that takes the STL file and converts it into a sequence of "G-Code" instructions which tell the head where to go and how fast, while also telling the extruder when to turn on and off (and at what temperature) plus lots of other instructions for other machine parameters. Good slicer software allows you to set thickness of layers, wall thicknesses, types of infill inside the solid bits, whether you use a raft/skirt, the type of supports you use for overhangs etc and all sorts of machine parameters like using different temperature for the first layer. I like PrusaSlicer (free version) so I used this for everything.
Before use you have to level the bed by setting the head to the "home" height, pulling the power plug and then moving the bed by hand to the four corners. In each place you adjust the knurled nut to set the distance between the nozzle and the head using a sheet of printer paper as a feeler gauge (going around 2-3 times because the adjustments interact). Some people say you should do this before each print, but I haven't found the need.
The next step is to prepare the print file. I picked a "Yoda" bust from Thingiverse for my initial tests as it had lots of detail and features like overhangs to test the printer's abilities. I loaded the STL file into Prusaslicer and set it for position on the bed, 180degC nozzle temp (190 for first layer), 0.15mm layers and a 3 layer raft with 2mm skirt*. They supply a short (10m) length of PLA filament to play with, but I had read that it's pretty naff stuff so I had a 500g spool of HobbyKing matt-silver "premium PLA" to use.
Once the g-code file is prepared you just copy it onto the micro-SD card and transfer this card to the printer. The printer prints whatever is the most recent file on the card - no menu to select from or anything. So following the instructions I moved to my first print. With the power off I lifted the head around 30mm up from the surface**. Then I pushed the "+" button and introduced the fibre. The "+" light flashes rapidly while the extruder warms up to purge any old plastic from the nozzle and starts the flow or new material. After a couple of minutes the flashing switches to slow and you can push the button again to stop the purging. This was now ready, so I pressed the start button and...nothing happened.
Nothing continued to happen for about a minute, and then the head & bed moved to their start positions. Another 30 seconds and the printing started:
(https://i.postimg.cc/PrZh8vfD/IMG-20201226-101831.jpg)
That first print was done with no supports, was left overnight to print and the result was much better than I expected:
(https://i.postimg.cc/BZR46B3s/IMG-20201226-101906.jpg)
One of the most impressive features of this thing is that it is extremely quiet. My "study" is a doorless 8'x4' room off our main bedroom that was originally a walk-in wardrobe when we bought the house, and I left this print running all night - The Boss didn't even notice it was running.
But I had already spotted a snag. As supplied it has a filament spool holder which seems to be designed for something like 4" spools. All the filament I've seen comes on at least 8" spools. In the above print I dodged the problem by turning the spool-holder outwards and sitting the printer on a box so that the spool hung over the side:
(https://i.postimg.cc/KjkqwTpD/IMG-20201226-101824.jpg)
This worked initially, but as soon as the filament started running down it snagged on the flanges of the spool, interrupting the print. There are lots of alternate spool-holder designs on Thingiverse, but to print one I needed a working spool feed. So I went into the workshop and grabbed a piece of 1/8" plywood, drilled four holes in it and produced this crude but workable short-term solution to bring the spool back over the chassis where it could feed more easily:
(https://i.postimg.cc/JzL837t2/IMG-20201226-113711.jpg)
This is working well for my first "large" print - the improved spool-holder:
(https://i.postimg.cc/yd3TnHbD/IMG-20201226-155059.jpg)
(https://i.postimg.cc/vB42Nmhy/IMG-20201226-173542.jpg)
This print is nearly the width of the bed, and is exposing one of the known weaknesses of this machine:
(https://i.postimg.cc/wBv2yJ5c/IMG-20201226-155055-2.jpg)
The initial layer(s) of the skirt and the raft haven't stuck very well to the mat in this corner, so at the plastic cooled this corner has warped upwards. As it happens this isn't important for this print, so I've let it continue. There are four possible solutions to this problem:
1. It might just be that I need to re-level the bed. Personally I think it's more than that, but I will check it again when this print finishes.
2. I could increase the extruder temperature for the first layer to make it "stickier" (this can be dome with settings in the Slicer software)
3. I could rub Pritt glue-stick onto the bed before printing (according to some websites)
4. I could use a heated bed.
I'll try (1), but I don't think it will work. Then I'll try (2), possibly increasing the thickness and reducing the print speed of the first layer to help it "wet" to the printing matt. I really don't want to try (3) because if that's the answer it will need lots of tedious cleaning between prints to get that mess off the mat. And then there is (4)...
As I mentioned above, I bought an aftermarket heated bed when my Better Third first told me what she was getting me for Xmas. It was about a tenner, and will bolt straight on to the machine. But as supplied it has no temperature sensor and/or controller. It needs either a 12 or 24volt supply, and so I've knocked up a simple temperature controller using an LM35, and op-amp, a couple of resistors, a pot and a relay (apols to the Arduino generation - I was born in the mid Palaeozoic era so I do this sort of thing in analogue) which works well enough. On the "keep it simple" principle I will try the heated bed when I've proved that I can't achieve the same thing with just different settings. Amongst other things it needs 12v at 5A, and that will need a power supply with a noisier cooling fan that might cause the machine's indoor residence permit to be revoked.
Once this spool holder is done I will be trying the first "real" job. I want to make some structural parts for the spoiler blades mechanisms of the 1/4scale Fournier RF4 (radio controlled aeroplane) that I'm building - mainly because I can't see how to assemble the designer's drawn solution without the assistance of nanobots and telekinetic techniques.
But overall - I'm very impressed with just how good a machine this is for such a low price.
AS
*This first print got abandoned because the head drives couldn't keep up with pruslicer's default speed (60mm/sec) so I re-sliced it with a global limit of 30mm/sec which worked fine. As I get to know this machine I'll try replacing this global limit with specific feature speeds to "tune" it for optimum performance.
** I have since found out that if you don't do this the puddle from the initial purging of he extruder melts a small pit in the print mat
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So here is that spool mount completed (took about 6 hours to print):
(https://i.postimg.cc/MTtCvSK9/IMG-20201226-232326.jpg)
Note the T-slot feature which slides over the flange features in the moulding on the top of the column
(https://i.postimg.cc/fyr1ffdX/IMG-20201226-232331.jpg)
This is where the base warped upwards due to the first layers of fibre not sticking to the bed (as mentioned in the previous post). In this case it doesn't matter, but I'll need to find the best solution to this. I have just re=levelled the bed and it was indeed slightly low in this corner, so that may be it (but I don't believe I'm that lucky).
(https://i.postimg.cc/cHsqxHZK/IMG-20201226-232337.jpg]https://i.postimg.cc/cHsqxHZK/IMG-20201226-232337.jpg)
Here's the inside of the T-slot - the camera exaggerates what is actually just one layer of loose strands which were removed by a few scrapes with a small screwdriver. Frankly I'm stunned - this is a void about 1/2" wide which the printer has bridged without supports. I didn't add supports because I could see them being difficult to remove cleanly, and this amazing little machine has done without them!
(https://i.postimg.cc/hvjHm5Xc/IMG-20201226-232521.jpg)
This is how the support is used. The existing spool holder is unscrewed from the side and pushed into the slot, held in place with a short self-tapper into a boss which has been formed in the print. I used one of the screws that originally held it to the side - perfect diameter but about 3mm too long, so it broke through. I was very impressed that (a) the hole was precisely the correct diameter for the self-tapper so it screwed in easily, (b) the material was strong enough to hold the thread so I could nip the screw up to a hard stop with no feeling that it might be stripping, and (c) the boss showed no signs of wanting to split even though the "grain" (the print layers) ran along the axis of the hole. This gives me lots of confidence in the strength of PLA. As seen here I just need to unclip the spool shaft and put it on the other side.
(https://i.postimg.cc/G3g0Rdf2/IMG-20201226-233703.jpg)
These images show the finished item mounted on top of the column with a 0.5kg spool, showing the much simpler and more direct feed into the extruder:
(https://i.postimg.cc/Jh3VCJwV/IMG-20201226-234819.jpg)
(https://i.postimg.cc/cLnGT2XJ/IMG-20201226-234829.jpg)
(https://i.postimg.cc/mrWfnj5y/IMG-20201226-234843.jpg)
The whole assembly is MUCH more rigid and generally satisfactory than the original design.
AS
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No such thing as a bad printer just some haven't reached their potential yet.
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Looks neat and great value. I like my Prusa i3Mk3 but as I only play with it perhaps I should have bought what you have!
Happy New Year BTW!
John
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Update:
The next item I printed is a mount for the control unit. For this print I re-levelled the bed and then changed the print settings for the first layer (.35mm thick and 205degC extruder temp rather than the 0.2mm and 180degC I use for the rest). This completely cured the adhesion/warping problem noted in the previous posts, so I still don't have a need for that heated bed:
(https://i.postimg.cc/Y2PtgSGc/IMG-20201227-145517.jpg)
That made this part (the flash makes it look rougher than it is):
(https://i.postimg.cc/BQ14CGHj/IMG-20201227-151427.jpg)
...which mounts the control unit on chassis rails like this, making it a much more compact and neat machine:
(https://i.postimg.cc/FHyv2gPm/IMG-20201227-151507.jpg)
(https://i.postimg.cc/HkDHZP9B/IMG-20201227-151516.jpg)
I'm getting the impression that a 3d printer is just like a lathe or milling machine - the trick is to learn its foibles and work to exploit them so that a skilled operator can make good parts even using cheap machine through practice and feel.
AS
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It's true Allen, most machine tools have their own tricks and techniques to learn, but after a while you get the hang of them and satisfying work starts emerging. The process often has a lot more to do with the "bench to tool interface module" (the user) than the tools themselves.
Nice progress with your inexpensive printer! :ThumbsUp: :ThumbsUp: :ThumbsUp: :cheers:
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Allen:
Personally I think 3D printers are more like shapers, rather than a lathe or a mill - you can make just about anything on them except any money.
My first 3D printer was a cheap Chinese clone printer kit, relatively speaking it was cheap, but it was still a lot more than you paid. You learn a lot about 3D printers and 3D printing by trying to wring the most out of what you've got. Keep at it, but it looks like you are doing just fine.
Yes indeed, bed-leveling is important. If that first layer doesn't stick properly you might as well abort the print, fix the problem, and try again - because it won't get any better. With my first printer I'd have to re-level the bed every couple of weeks. With my current printer I only level the bed after I've had to work on the print head or the bed.
Be sure you get, and keep, lots of spare parts on hand. I kept spare nozzles, heat breaks, heater cartridges, thermistors... I kept adding to the list as things broke and I had to repair them. You might also want to grease the linear bearings if you haven't done that already, they probably came bone dry - mine did. (Unless it's got the IGUS style bushings, then - NEVERMIND.) I actually kept a spare set of bearings for my first printer and just swapped them out when they needed work. (When they started getting noisy.)
Apparently 3D printing is kind of addictive, because when something breaks you'll feel the need to get the printer running again right away. If you don't, you'll start to go into withdrawal - DAMHIK.
Don
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My Better Third bought me one of for Xmas:
Allen:
I meant to ask this earlier. I know what a "Better Half" is, I know what a "Smarter Half" is, I even know what SWMBO means.
But "Better Third" has got me scratching my head, come on... Give. (Enquiring minds want to know.)
Don
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I used to describe her as my Better Half, but the Weights & Measures Office pointed out that this claim was a grossly inaccurate from a mass/volume perspective.
Meanwhile...
I've been experimenting with settings to get to know the machine. Printing (Hobbyking "Premium" PLA) down at 180C definitely gives better results, and the raft serves no useful function so I've switched it off. I found the "retract" setting that pulls the fibre back from the extruder between prints (like when crossing gaps) which has completely eliminated stringing and surface pimples.
I also Just discovered by experiment that the "accurate" feature is the outline, not the planes parallel to the bed. I designed a part that looks a bit like a saddle clamp, and printing it sitting flat on the bed gave results that were OK, but not brilliant. But printing it sitting on its edge with the groove vertical and the screw holes parallel to the bed makes a much cleaner, more accurate part. This is counter-intuitive and a useful thing to know.
Finally I've discovered that it's better to create the part geometry (STL file) two or three times real size and then shrink it down in the g-code generator (pruslicer). This seems to give much better surface detail - possibly something to do with the way SolidWorks generates the STL files.
Every day is a school day (unless you're in Tier 4)
AS
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I used to describe her as my Better Half, but the Weights & Measures Office pointed out that this claim was a grossly inaccurate from a mass/volume perspective.
...
:ROFL:
Better not EVER describe her as the better two-thirds!
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I'm not going there at all with ANY COMMENT WHATSOEVER about better 1/3rds 2/3rds etc. :zap: :zap: :zap: :disagree: :disagree: :disagree: :disagree: :Lol:
I have found rafts to be helpful only on rare cases. Most of the time they waste a lot of filament and add cleanup effort. If you do have a small part to make and are having trouble getting it to stick to the bed, a brim feature works great. This is just a single layer "mat" of material 6 or 8 mm out from the first layer outline, to increase the adhesion layer area.
You have discovered how build direction can be a pain or that it can work for you. Build direction is a lot like thinking about grain direction when doing woodwork. (yes, I know it's a bad word to use here.) Lets say you want to print a chisel. If you print it starting at the handle end upward along its' length, it has little strength because the forces on it work on a small area. Lay it down on the table, making only a few strong layers of large area, it will be much stronger. You can always make a separate glued on piece for the parts you chopped off the handle side to get the part laid on the bed. :cheers:
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Oh, I don't know... He could probably get away with describing himself as the Lesser 2/3's of the equation.
Designing for 3D printing is quite important. I think of the parts as plywood when I'm printing them. If a print is going to come apart it's most likely to delaminate between layers. I try to orient parts when printing so that any stresses that will be applied to the part will try to crush the part, not split it apart. Again think plywood, it's relatively easy to split a piece of plywood between the laminations with a knife. Cutting it in two with a knife through the laminations - not so much.
Now to give you something else to think about. Shrinkage, and I not talking about what happens in the swimming pool. If you've tried printing a precise part and had it come out different dimensions than what was designed, welcome to the world of pain felt by metal casters. What's that got to do with 3D printing - a LOT! Both heat a material enough to change it from a solid to a liquid, and both have to deal with the effects of thermal expansion. When we print a part we're printing at a couple hundred degrees C - ish. If we print it to the design dimensions at that temperature, when it cools to ambient temperature it's going to shrink. We get around this by telling the slicing software to scale the part up and print it a little bigger. Then when it shrinks it's the right size, eazee-peazee.
Of course if you're just printing a 3D bust of Yoda to sit on the shelf, do you really care if it's 97% of the size it was designed at? Just sayin' that if you are printing parts that need to fit a dimension, then shrinkage MUST be considered.
Don
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I am just seriously toying with the idea of getting an Ender 3, possibly a v2 or a pro.
Could you expand on your shrinkage warning please, do you have to physically design your 3D model oversize to start with, or does the printing software deal with it.
I use Solidworks, so can save my parts as STL files very easily, I am thinking in terms of printing some parts to do a trial assembly prior to making them from metal, but I dont want to have two separate models for plastic and metal.
Phil
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pgp go Ender 3 V2. I find that when printing parts supplied by thingiverse, yeggie etc. the pla prints to size but abs I need to increase the size by 1-2 percent due to shrinkage.
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pgp001:
Design the parts to your desired size. The slicing software gives you the option scaling the part, at least I know that Slic3r and Simplify3D both do. I don't know about Cura since I don't use it.
When I built my first printer, it was a Chinese clone of a Prusa I3, I couldn't figure out why my parts weren't printing to dimension. I had just gone down both the 3D printing and 3D CAD rabbit holes, so I suspected that I had screwed up somewhere. I eventually figured out a way to modify my printer's steps/mm setting using g-code to get the right dimensions. I didn't want to mess with the Arduino programming because I didn't have the original files for my printer, and I didn't want to take the chance of breaking an otherwise usable printer.
A couple of years later I saw a video by Clough42 where he described a similar problem that he was having with a 3D printed part, and his simple fix using the slicing software. I had one of those Homer Simpson head smacking "DOH" moments when I realized that I was just compensating for shrinkage, and not correcting for a Chinese factory boo-boo in setting up the printer.
You can calculate the shrinkage amount from the coefficient of thermal expansion - if you want to get really precise. You can find that coefficient of expansion on-line for just about anything. I usually just scale up the model by 102%-103%, in all axis, and print a test part to see how close I am. It's usually good nuf for gubmint work, if not then I change the scaling factor and print it again.
Don
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Hi
Thanks for that explanation, I just watched the video you mentioned and it all makes sense.
I have just been looking at the specs for a Geeetech A10, and it looks almost the same as an Ender 3, there seems to be a price and availability advantage with those as well.
Does anyone have any first hand experience or advice on the Geeetech before I decide on what to buy. I am still leaning towards the Ender 3 V2, but there might be a wait to get one at the right price.
Phil
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Not sure about the price advantage - There's a vendor on Banggood.UK who currently offers the Ender 3Pro for around £150 with free shipping (shipped from within the UK - takes about a week). The 3Pro has the stiffer bed mountings, and it also has the magnetic building mat like my little EasyThreed - this is very good for printing materials that need bed temperatures below around 80degC, but if you want to do any of the stringer materials that need a hotter bed you'll need to swap it for the non-magnetic bed of the base model Ender 3 (costs around £15).
I've just ordered one of these Ender 3 Pros, because I've realised that one of the jobs I want 3d printing for* would need the parts chopping into far too many pieces to print on the smaller machine. Once it's here and running I guess I'll have to decide whether I should hang on to the little one as a spare or sell it on.
AS
* I do electric ducted-fan RC models, and forming intake/exhaust ducts in balsa or 1/64" ply is a pain. I've been doing sone trials and it's actually very easy to take accurate measurements and then produce lofted models in SolidWorks that I can output in STL format for printing. Even the little EasyThreed machine seems quite happy printing complex duct sections with a 0.8mm wall thickness, but only in sections that would fit into a 4" cube in each print
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Hi Alan
I am still thinking I will push the boat out and get the Ender 3 V2.
There seems to be less vendors available for those though, I can get one from Technology Outlet for £239 post free but they are not available till 25th January, so they must be in a shipping container somewhere on the high seas I reckon. Bangood also sell it for a similar price, but again not available till the end of the month, so its probably on the same ship. Sellers on ebay are wanting £300 plus.
I have just been playing around with the Cura software, and it seems that I will also need a smaller 0.2mm nozzle for it to be able to do the tiny lettering on the hub rings I want to make for the Marshall Portable engine wheels. With the 0.4 nozzle selected it just ignores the lettering altogether.
I keep thinking of all sorts of things I can make with it, so it should be good fun and very useful.
Phil
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I keep thinking of all sorts of things I can make with it, so it should be good fun and very useful.
I brought my "Cheap as Chips" printer early last year and used it to teach myself about 3D printers. After the initial flurry it hardly has been used. The current plan is it will be used to make jigs if required but it has not been required (so far).
My friend's 30 year old son, after the initial flurry of printing space monsters/dragons ::) etc, doesn't seem to use his either.
Jo
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Phil, how big is the lettering on your hubs, might be possible to CNC it.
At least going down the CNC route I get plenty of use out of that. If I did have a 3D printer I think it's main use would have been the odd pattern but as I can make wood or plastic patterns on the CNC I can't see me buying a printer any time soon.
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At least going down the CNC route I get plenty of use out of that.
CNCs are rather more expensive than a 3D printer ::)
Jo
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I keep thinking of all sorts of things I can make with it, so it should be good fun and very useful.
I brought my "Cheap as Chips" printer early last year and used it to teach myself about 3D printers. After the initial flurry it hardly has been used. The current plan is it will be used to make jigs if required but it has not been required (so far).
My friend's 30 year old son, after the initial flurry of printing space monsters/dragons ::) etc, doesn't seem to use his either.
Jo
It was the same for me. I bought my 'Cheap as Chips' printer early last year, about the same time as Jo. I used it more or less continuously during the first months of this pandemic, to print face visor frames and other bits of PPE for our hard pressed health service (NHS) workers. Since then, the NHS supply problem had been sorted and my 'Cheap as Chips' printer is now gathering dust on the top shelf. I rarely find a use for it. If anyone wants a bargain, they can come and take it away for free. Oh! while you are here you can also take away the 3D bust of Yoda and the other things I downloaded and printed from Thingyverse
I have decided , if I ever need a high quality printed 3D object, I will go to a professional print house like Sculpteo or Shapeways. They can produce a super high quality print in a vast range of plastic materials. They also offer Laser sintered metal prints, for a much higher price.
Others, will no doubt get different milage
Stay in, stay safe
Mike
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At least going down the CNC route I get plenty of use out of that.
CNCs are rather more expensive than a 3D printer ::)
Jo
Probably cheaper than one that prints metal, my CNC produces metal parts too. Though the small 3040 CNC routers are not too pricy and would be more than capable of making patterns and the odd small non ferrous part.
Also CNCs are not expensive if you are given them :LittleDevil:
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So, time for an update...
The machine worked well enough, and I was getting to grips with its foibles. But three days after I wrote the above the extruder nozzle started clogging. In every print the extruder would stop extruding after the first 10-15 layers. I tried different nozzle-bed clearances, different nozzle temperatures, different layer thicknesses and retraction settings but it made no difference. I would clear the nozzle by withdrawing and then hot-feeding the filament until it gave a full normal extrusion, but it just clog again. So I had a bit of an exchange with Hobbyking customer service, and they agreed to take it back for credit. I was happy to take store credit rather than a refund because I'll generally spend the ~£80 with HK within a month or six.
So that machine wasn't as usable as I initially thought, but after using one I had decided I definitely wanted to have a 3d printing capability, so I looked around. The general view seemed to be that for most aeromodelling uses the Creality Ender-3 (as also mentioned by Cornixt) was the popular choice. It's bigger than the EasyThreeD one, with a printing area of 220x220mm and up to 250mm high, it has a heated bed and is generally a more sophisticated machine. They've been around for a while and are available in a range of versions from the original to the latest "V2". The list price of the latest model is around £300, while the original model is still available in some places for as little as £130. Hobbyking offer the original model for around £140 but only from the main warehouse, which accrues up to well over £200 with shipping, and you'd undoubtedly pay VAT & duty on that at the moment. But I looked around and found one of the Banggood UK shops which was offering the updated "Ender 3-Pro" discounted to about £150 with free shipping, shipped from the UK (so no VAT paid and no duty) - a lot cheaper than the V2 without losing too much in functionality, so I bought one. It arrived in about a week. So now I'll review the Ender!
This is a much bigger, more complex and more capable machine than the EasyThreeD. and it also needs quite a lot more assembly. Assembly takes about 40 minutes, and all the required tools are in the box - a set of rather nice long-series ball-ended allen keys, a screwdriver, some spanners and a pair of side-cutters which are actually for cutting the filament rather than for assembly. Oh yes, and there's a scraper for cleaning stuck plastic off the print surface. The assembly sequence is straightforward, guided by 16 colour drawings (rather than written steps) in the instructions. The whole process is made simpler by the way that all the screws are separately bagged and labelled to make it clear which ones are used where. Th3y provide spares of some of the screws, plus a spare extruder nozzle and a spare PTFE clamp fitting for the filament bowden tube. There was one sequence error, but it's immediately obvious when you get to it and it only requires removing two screws and then replacing them again.
In the box there is a microSD card with a USB adaptor, and that contains a video of the assembly (ignore it - it has some serious errors in it), a PDF start-up and operation manual, the Cruzer slicing software* and a number of sample things you can print. As with the EasyThreeD the easiest way to use this machine is to put your print files (g-code) on the microSD card and then plug that card into the machine. But it's different in that the Ender has a control panel with a display, so you can read the card and choose which file to print. But I'm getting ahead of myself. The finished machine looks like this:
(https://i.postimg.cc/Jzdx0vyw/IMG-20210109-090805.jpg)
On of the features of the "pro" model is the magnetic printing mat (like the EasyThreeD one but bigger and with much firmer magnets) which is nice, but you must keep the bed temperature below 80degC when using it or the magnets are destroyed - so if you want to print ABS or Nylon you have to swap the bed for a glass one (available as an extra). Before starting you have to level the bed, which is done by setting the head to "home" and then switching the stepper motors off on the control panel. You then move the bed around the extremes and wind the levelling screws (which have very nice big wheels on the heads). Once the bed is level you introduce the filament to the feed motor - I found it initially a bit fiddley to get the fibre through to the exit hole, but you just find the knack. You then push it through until it has passed down the tube to the extruder and you're all set.
Everything is now done on the control panel. It has a single knob that you press to get a menu, rotate to move between menu items and then press again to select things like any other "jog wheel" interface. From this panel you can select things to print, start/pause/abort prints, preheat the nozzle and bed, feed/remove filament etc. You can also override the programmed settings for temperatures (in mid-print if you wish), fan speeds and a few other things. And when it's printing you get this "status" display:
(https://i.postimg.cc/QM9bTm5F/IMG-20210109-175916.jpg)
On there you see various useful info like the temperatures and fan speeds, the duration so far of the current print and the approximate %age completion. So in that picture you see the job had been running for nearly 17 hours and was 62% complete - it was a big one! This is what it was printing (it's the housing for a double tool drawer that clips under the front next to the control panel):
(https://i.postimg.cc/VkN4YmkB/IMG-20210109-175941.jpg)
I've printed quite a lot of things with the Ender, and it's an order of magnitude better in print quality, but then it's more than double the price. But it has impressed me so far.
AS
* I initially tried it, but quickly reverted to my preferred Prusaslicer software which gives me much better control over the machine parameters - this is a matter of personal choice
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I can only agree with your sentiments about the Ender 3, AS. I have had one since last February and have found it to be a wonderful machine for the price. Amongst other things, I have made a 1:25 scale model of an engine in our museum with all the parts except piping, decking, etc being printed. Even most of the visible nuts and bolts are actually printed as part of the structure they relate to.
Ian.
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* I initially tried it, but quickly reverted to my preferred Prusaslicer software which gives me much better control over the machine parameters - this is a matter of personal choice
Alan
Re the Prusaslicer software, is that a free download or did you have to purchase it ?
I have just pulled the trigger and ordered the Ender 3 V2, which is due for delivery around 25th Jan, so I am getting everything I need ready for then.
What filament are you using by the way ?, there seems to be a lot of choice and price ranges out there and I have no idea where to start looking really.
How much do you think that the ambient temperature will affect printing, mine will have to live outside in either the workshop which is only at around 12 to 15° C when I am in there but is regularly down to only 6 or 7° C overnight. or in the garage which is only and odd degree above outside temp most of the time. I am thinking I will need to organise some airtight storage for the reels of filament to stop them absorbing moisture.
Thanks
Phil
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Re the Prusaslicer software, is that a free download or did you have to purchase it ?
It's a free download. I also found (somewhere) a Prusa profile for the Ender 3 family of printers which saved me some setting-up effort - if you get one ping me an email address and I'll send it to you. I've tweaked that profile by setting it to heat the bed and the extruder nozzle concurrently at the start of the print. The standard settings heat the bed and then the extruder which takes much longer. I felt that the PSU must be rated to do both at once, and it hasn't complained.
For completeness - other than Cruzer and PrusaSlicer other slicer programs you might also like include Meshmixer and Netfabb (both either free or with free versions). I like PrusaSlicer because it has a very logical layout to the various settings for the chosen printer, the current print and the chosen filament, but I know other people who find Cruser easier to use. Each to their own!
What filament are you using by the way ?, there seems to be a lot of choice and price ranges out there and I have no idea where to start looking really.
I've used PLA filament from Hobbyking - it's "Matt Silver Premium" rather than the "X3" range, and I have used orange PLA+ from 3d Printz Ltd (in Telford). Both print nicely, and the PLA+ is significantly stronger. I've ordered a reel of black PLA from 3d Printz which should arrive on monday because I want to make some add-on parts for the machine and they'd be much nicer in black. There are lots of filament suppliers and I've barely scratched the surface, so I'd suggest just going by the reviews and try them. PLA and PLA+ are very easy (unfussy) to print with, but when I have more confidence with the machine I intend to try the more demanding materials (ABS, Nylon etc) and also the printable elastomers (TPU etc). In fact I van even think of uses for printable PVA when I get a round tuit.
Note that filament should arrive vacuum packed with a sachet of silica gel to keep it dry between manufacture and use.
How much do you think that the ambient temperature will affect printing, mine will have to live outside in either the workshop which is only at around 12 to 15° C when I am in there but is regularly down to only 6 or 7° C overnight. or in the garage which is only and odd degree above outside temp most of the time. I am thinking I will need to organise some airtight storage for the reels of filament to stop them absorbing moisture.
As you say, the main thing about filament is too keep it cool, dry and free from UV light, so if you're storing it outside you might get one of those plastic boxes with a clip on lid and some re-bakable desiccator packs (we had some from when we had a caravan) and store filament in there. In other words the damp might be more of an issue than the cold. I keep mine in just such a box even though it's indoors. If it's possible you might perhaps try to store your filament somewhere indoors, but I doubt it's a major issue provided you can keep it dry. I don't think there should be any problem about printing outdoors in the cold - the print bed is heated, and the filament gets heated through the extruder, and most of the issues people discuss are how to ensure the freshly-extruded layer cools quickly enough to prevent distortion or warping. Indeed the part-cooling fan in the print head is there solely to do this. The only problem I can think of might be condensation on the plate before the start of the print - especially on the V2's glass bed which heats more slowly. But you could mitigate this by using the "pre-heat bed" option on the control panel, or perhaps add a standard bit of g-code that heats the bed for (say) 3 minutes before each print.
One thing that might be an issue - it's generally a good idea to keep an eye on the print in-progress. Certainly watch it for the first layer or so to make sure it has stuck to the bed, and then maybe check on it every hour to make sure the filament hasn't clogged or (as happened to me once) the part hasn't unstuck from the bed and moved out of the way so that the extruder is just squirting spaghetti into space!
But I'll try to keep this thread updated with how I'm getting on with mine - perhaps you could do the same with yours when you get it so we can "share best practice" and "capture lessons learned " as all the best management consultants say...
:LittleDevil:
AS
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Alan
Thanks for the very comprehensive reply, I can't wait for mine to arrive now :ThumbsUp:
Phil
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People asked what I'd use this thing for, so I thought I'd come back on that. As some of you know my main hobby is RC model flying. A week or two back I suffered a bout of Paypal Tourettes in response to a one-day sale bargain mailshot and bought a waterplane - a HobbyKing Skipper:
(https://i.postimg.cc/ZqKBBdXB/Skipper.png)
It's a cheap bit of fun, but you look at things and can't resist correcting mistakes. The motor cowling on this aeroplane is a classic example of style over function. The cooling intakes are behind the motor and there are no cooling exhausts. There are also no drain holes to allow water to escape. I could have carved a wooden replacement from balsa, or carved a plug and moulded a replacement in glass, but both of those are time-consuming especially where there are design iterations. But 3d printing combined with a CAD system is a very different matter. So I persuaded the supplied cowl to let go (a little gentle easing with a scalpel) and then drew around the back face, marking the top and bottom centre datums. This drawing was scanned into solidworks to use as a template. I them measured the distance from the rear face to the spinner ring and some reference dimensions so that I could locate the spinner face in three dimensions with respect to the rear face. Using all of this my first approximation was to produce a replica of the stock cowling to confirm I had the geometry correct:
(https://i.postimg.cc/brPdszkZ/4-2.jpg)
A rough print, but it fitted like a glove (other than the detail that the stock foam spinner is 33mm diameter and my metal replacement is a 30mm one) and has the correct lengths. So then to solve the design shortcomings. The motor in this aeroplane is a brushless "outrunner", which means the windings (the hot part) are on a stator in the middle and the magnets are attached to the inside of a rotating outer can. To properly cool it the cooling air must be directed into the front of the can and over the stator windings. To achieve that needed the air intakes to be moved to the front, with a baffle blocking most of the path around the outside of the can. The air would then exit from the rear of the can and would need some exhaust vents. Finally a combined air exhaust and water drain would be needed at the lowest point. Several hours of shouting at Solidworks (because I haven't used it for anything complex in ages, and one forgets the basics!) went through a number of iterations before evolving into this:
(https://i.postimg.cc/Z5kDSrCS/Version-3.png)
(https://i.postimg.cc/pX5140VC/Version-3a.png)
(https://i.postimg.cc/66mmHsKT/wireframe-3.png)
(https://i.postimg.cc/tghgJ1Wb/23.jpg)
(This is a rough print with just the support material pulled off - there's about 5 minutes of work with a needle file and some 280/400grit paper to clean it up for actual use. It's also printed in PETG because that's the only white filament I have at the moment. PETG is horrible stuff to print - it's stringy & brittle and suffers pimples and rough spots. As soon as I can get some in white I'll be printing a replacement in PLA or preferably PLA+ for a much better finish).
There were three major design concepts, each of which had several development increments, so I've made about nine or ten versions before settling on this one. Each one takes 3 hours to print, but it's not me-time - I just go off and let it get on with the job. I do lots of things like this, and this machine makes things possible which would have taken days or weeks to achieve using traditional machining or hand-fabrication. The ability to go straight from the Solidworks model to a finished part rather than producing drawings and then spending days machining & filing is what makes it useful. It's rather like the olden days when I would produce drawings and sent them down to the toolmakers to make the thing, but without the incessant stream of complaints about how my drawings were unclear, ambiguous and/or impossible to actually make (what do you mean you can't do a blind 5mm undercut 30mm down a 3mm bore?!).
;D
AS
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I've been 3D printing for 5+ years and started with a Da Vinci 1.0 (ABS only machine) then a cheap chinese knockoff Prussia I3 for PLA and after much modifying I purchased a Ender 3 v2 and am mightily impressed with it. I use Cura for slicing as it has good support methods. The first mod you need to do though is replace the plastic filament feed with an aluminium version as it will crack fairly fast and a piece of capricorn tube to place in the hot end as the teflon tends to melt a bit and cause problems down the track. A good source of is the U tube channel 'Filament Friday'. Oh yes 3D printing can become a dark, slippery rabbit hole from whence you may never return.
Pete
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Ender3 Pro user, I switched to PrusaSlicer from Simplify3D last week. V2.3 comes with profiles for most or all of the Creality printers. Very complete, with concurrent hot end and bed heating, beep at end of print etc. (I think Cura has a terrible UI from a usability pov)
I found this YT explanation of managing the profiles etc. the best of several: https://www.youtube.com/watch?v=Wz2Soog4HkQ It essentially lets you customize the pre-configure filament settings for your specific ones.
A most useful machine in the shop.
Gerrit