Design aspects + recommendations for entry-range 3Dprinter sought + discussed

[Geebee]

Hi everybody

Having read across the forum and some web sites I want to enter the 3D world with as little a reasonable budget as necessary (aiming at <500€ for machine with bed plate and first spool of filament). I am under the impression that one must jump into the pool to know what to keep one's eyes upon yet I would of course start with sth. that meets my expectations and assumptions as listed below, especially if they be correct.
Summing up what I kept in my memory my prior concerns are (not necessarily in this order):
1) stability and inertia/damping of the structure.
is it advisable to build a system as with the old hi-end record players, i.e. heavy static structure on dampers with light and rigid beam and as little as possible moving mass? I read about a wooden frame (favour the idea) being user and modder friendly yet noisy and somehow challenged by vibration, alloy profiles being a nuisance in case of modifications (which I hope would not occur too often)
2) the use of technology to reduce play/tolerance in movement of extruder and evtl. beam : cog rails/wheels vs. stepper/flexible band or wires etc.,
3) little need for repeated calibration. Is the re-occurence due to temperature changes like with many precision devices or is it due to wear in the machinery? I read of devices being difficult to calibrate (Rostock - love the design btw).
4) availability of / reliance on open software.

I may have forgotten some aspects now that I write this down yet I would like your expertise/comments earlier than never.

Ah yes,
5) - some parts, i think the extruder/nozzle,"hot tip" or what is it called should be preferrably metal - which are these?
And
6) this may be important since I don't know what awaits me - the user friendliness of the software. Not being nerd neither know-nought in technical matters (even studied mech. eng. once!) I would prefer a viable interface.
7) No need to have a display/key pad or such on the printer since the surf station is running/idling most of the time anyway yet I would like to know that the job CAN be uploaded to the printer to make the production proof against any connection trouble.
8) To reduce the inital capital surge I would gladly assemble the printer myself, even provide the frame structure , if there are suppliers of decent electro-mechanical kits that leave the choice of the structure and assembly to the buyer.
Living in western Europe some models/brands may be harder for me to get at than others but let that not stop you from any suggestions. I have no professional interest in 3DP. Technology-curious by principle I want to experience a little creation instead of merely sketching and/or digitizing at home as I did till now.

Thank you in advance for any feed back

[curious aardvark]

stuck for choice with kits.

Delta's look easiest to build and most fun to watch :-) Plenty of kits for around the £350-400 mark.
Personally I'd make sure you had an sdcard reader and lcd screen.
That way the printer doesn't need to be tethered to a pc.

Heated plate - not essential, can be useful but in atoss up between heated plate and screen/card reader the heated plate would lose, by a large margin.

Last time I used my heated plate was simply because it was 12c in my workshop, put the plate on 30c just to get the pla to stick a wee bit better.

[richardphat]

My opinion...

1) one is a big fail in printer world, unless we're talking about 4-5 figures machine expect to vibrate a lot. Enough to make locknuts loose if not maintaining for a while. Comming from student working wit the vibration department.
2) Completely irrevelent, they aren't the one you should worry about. It's the shrinking that is the killer when it comes to tolerance, shape, the infill that affect your external walls if you screwed up for example.
3) For a machine under 1000$ I can guarentee you will calibrate often.
4) Open source is nice for that, Cura, Slic3r, Kiss, heck even Simplify3D I am starting to be curious about.

5) Get all, .35, .4 .5 and .7 if you can get .2 from nonstandard do get them. It's like a machining, you use appropriate fly cutters in milling, or drill press and drill bits. For printing efficiency get a set of nozzle pay extra if you must. Look for a printer that you can screw the nozzle in and out. Such as the ultimaker, the rostockmax V2 from seeme CNC.
6) Harsh answer, you don't want user friendly if you are concerned about the tolerancing. At the beginning yes, easy UI is nice, but really bottlenecked your ability to print if you don't configure the settings by yourself to print the way you want.
7) Ihmo, it needs to have a display or key reader. I got my prints ruined by my colleague for accidentally shutting down the pc while I was distracted. The SD key allows you to print with no interruption no worries. Further, printing on USB works, if you have the certitude nothing will mess with it.
8) Don't have an answer for that.

TLDR;
Yes, kit is the answer if you haven't figured it out by now.

[Geebee]

Thanx for the extensive reply, Rich!

My opinion...
1) one is a big fail in printer world, unless we're talking about 4-5 figures machine expect to vibrate a lot. Enough to make locknuts loose if not maintaining for a while. Comming from student working wit the vibration department.

OK, i will see to that i eventually put some weight on the frame of whatever machine but first I will have to find a priceworthy frame and/or kit. Since I live in a kind of outback here I may be forced to buy one to see one.

2) Completely irrevelent, they aren't the one you should worry about. It's the shrinking that is the killer when it comes to tolerance, shape, the infill that affect your external walls if you screwed up for example.

Good to know that I will have a loooong learning curve. Had hoped and feared to produce first parts in days of course.

3) For a machine under 1000$ I can guarentee you will calibrate often.

Okay, so I'll get decently trained.

4) Open source is nice for that, Cura, Slic3r, Kiss, heck even Simplify3D I am starting to be curious about.

Yeah, there may be a lot of programs to be tried. If only I knew what soft I will be using (depends of hw to be decided upon) I might start there and try to master the steps to production. I am not sure though what I will be using since even the OS for the preparative steps is debatable (Win/Linux or even OSx?). I'd like to know what to rule in/out but that's not so urgent as the hw decision..

5) Get all, .35, .4 .5 and .7 if you can get .2 from nonstandard do get them. It's like a machining, you use appropriate fly cutters in milling, or drill press and drill bits. For printing efficiency get a set of nozzle pay extra if you must. Look for a printer that you can screw the nozzle in and out. Such as the ultimaker, the rostockmax V2 from seeme CNC.

Not sure if I understood your first phrase- I should gather nozzles in lots of diameters, nonstandard being a brand name or what?
Know the names of machines and some extruders, yet lack of detailed photos of extruders I could not decide yet. Extruders do not fit all printers I assume. Or are they all screw-able with a common thread?

6) Harsh answer, you don't want user friendly if you are concerned about the tolerancing. At the beginning yes, easy UI is nice, but really bottlenecked your ability to print if you don't configure the settings by yourself to print the way you want.

Oh, by user friendly I did not mean graphic, colored buttons or talking. I feared sth. like text windows with Chinglish messages.

7) Ihmo, it needs to have a display or key reader. I got my prints ruined by my colleague for accidentally shutting down the pc while I was distracted. The SD key allows you to print with no interruption no worries. Further, printing on USB works, if you have the certitude nothing will mess with it.

So an USB stick might work on the USB port? What port does a device without LCD panel have for me? Just asking, hope to find out sometime.

Thank you!

[Geebee]

stuck for choice with kits.

Delta's look easiest to build and most fun to watch :-) Plenty of kits for around the £350-400 mark.
Personally I'd make sure you had an sdcard reader and lcd screen.
That way the printer doesn't need to be tethered to a pc.

Heated plate - not essential, can be useful but in atoss up between heated plate and screen/card reader the heated plate would lose, by a large margin.

Last time I used my heated plate was simply because it was 12c in my workshop, put the plate on 30c just to get the pla to stick a wee bit better.

Thank you Curious,

so a display is more important than a heatbed. That is impoprtant info because I had hoped not to need a display if only I had a port for a memory like a SD card, USB stick or other.

[richardphat]

Standard nozzle are .35mm, .4, .5 and .7 I might skipp some?

There are some aftermarket selling .2mm which isn't wide spread.

Alternatively, you can purchase nozzle that hasn't been drilled and ask some technician to machine non standard hole. They sell various of micro drill bit.

[Geebee]

Hello back Richard and Curious

I have now taken a big step forward in building my firstling. So. told me among other things that the NEMA steppers usually found on the market have around 10% of steps misses and that the end stop switches' connectors on the PCB boards may not even be connected to the circuitry, I got nervous and hopeless. Even more so when I heard other "premonitions" about the software adaptation to the individual printer's parameters being far from easy or sucessful, re-coding the better way to do it.
But I may have luckily found some pretty expensive but less used NEMA steppers, bought a Raspberry Pi B+, RAMPS 1.3 and Arduino 2560 R3 and other electronics parts, connectors and stuff and will now assemble the circuitry for my Prusa-Mendel or such. Hotbed will be an epoxy-carbon plate. Software for the Raspberry resides on a mysterious 32G microSD card.
Any comments on the selection? I will eventually report on my assembly progress if it befits this thread.
Thanks for your suggestions in the meantime and Happy New Year to everybody.