What I've been up to... (Burny burny)

[chalky]

Incredible - your level of patience far exceeds mine - I'd have given up after the 2nd attempt!

[GfK]

How come the 3D printed stuff looks so... rough?

[edit] Just watched the whole thing - I wonder if the roughness of the 3D printed thing is why you had so much grief getting a good imprint with it?  Maybe if it was smoothed out first it might be a bit less "grabby"?

[Dabz]

How come the 3D printed stuff looks so... rough?

Well, they dont come out spot on, you have the lines from the layers, remember, its 200c gear coming out that settles then goes hard, so you see layers, also, when its moving across the print, you might end up with the odd string of gloop, or nipples at points (See Jet the dogs tail), which you can cut/sand off.

This is a 400 quid machine using PLA filament, but even ones that run up to a fortune still produce prints that need to be worked on afterwards to tart them up. You can use different types of filament that makes post-print smoothing much easier, like ABS filament is reactive to acetone, so you can leave a print hanging in a jar with a little bit of acetone in the bottom and the vapour will "smooth" out the lines... At the minute, noone has really found a good matching way for PLA, the stuff doesnt really react to much.

I tend to use filler primer that you use on car bodys, works an absolute charm, but, the issue is, you still need to sand it off, and getting sand paper into some of them nooks and crannies didnt seem worth it, but that wasnt the real problem I was having, it helps though, the problem I was having is that when whacking down the sand (Or the pattern), you can clearly see even some intricate details were being released lovely, the thing that was knacking certain sections up was simply a bigger grains of sand lodging into the small areas, thus holding the smaller stuff above, so, when I was pulling it out, it was obviously tearing... There's no way I can beat that without being just lucky.

The green sand I'm using is my own mix of sieved play sand and bentonite as a binder, works really well, but, you can buy all sorts of different casting sand, some oil based and that, but, I'm only playing, green sand you can reuse really, get rid of the black bits, squish it back up, remoisture it and away you go... It can go a long way and just needs refreshing once in a while when you replace loses... Its inexpensive, 17kg of it cost me less then a tenner, oil based stuff is the opposite, not as reusable and rolls in at £20 for 5kg on eBay

So, unless I've got something really good to cast and, well, I know what I'm doing, lol, I'll just have to work with the cons of my green sand for now, and one of the cons is delicate work is hitty missy!

Dabz

[GfK]

Dunno if it helps but I watch loads of videos like this (3d printed stuff, wood turning, casting, restorations etc) and I've seen people use acetone vapour to smooth out 3D printed things.

Very flamey, though, so probably wise to keep it well away from the burny stuff!

[Dabz]

Yeah, I mentioned acetone in my post, seen it on, great for ABS filament, doesnt work with PLA... Nowt does... And, well... Fire should work, but I burn boiling water so have no hope for my piece!

Anyway, aye... Due to Enays post, I've just made this over a coffee [attached], at the minute, that is a workable project which I will be able to do something with and make look pretty at the end!

Dabz

[Derron]

GfK is right about the issues with your 3d print:

- first is the shape of the logo - it is not smooth, it looks like it uses too few vertices (when thinking of polygons) or has sharp edges (vectors...)
- the print shows some issues - like if there was heavy over-extrusion when the "shape" began

Elsewise you should be able to print with a layerheight of 0.3 (mm) and not see big "issues" - if your printer is having tight belts. I am using 150 euro printers (geeetech A10 - and before an Anet A6) and the only issue I had for long time was "adhesion" - printing on special glass beds now and once it is well leveled, it works as it should.

What I suggest for you with models like this: do changing layerheight prints. This way the ground plate could be print with 0.3mm - and the elements on top with eg 0.1. Why?
The big ground plate will take a while to print - so the bigger the layer height, the faster it will be done. Also the ground plate is easy to get "grind" by you (to be smooth - it does not have to look polished and glossy - of so, just take a little flame torch and go around fastly, it will make it slightly glossy again, as you bring back the surface tension of the PLA material). The top part will be printed in 0.1mm so you do not get these overly visible "ripples" which are hard to grind away with these little gaps (else you might come along with a small bit in your dremel --- and clean it up manually.

how the layerheight changes are to do -- depends on the slicer. Slic3r should be able to do on its own, Cura might require some addon. Else the basic idea is to have the model sliced with two different heights - and then use the gcode of layer 0 to "wherever the fine details start" + the gcode of the layer "where details start" to last layer.
Mix them in a file - and print this file.


What else is important: use chamfers! if your plate is not "laser cut", it will have slight chamfers when stuff like the logo "begins" - and when it ends.
Benefit of chamfers is, that sand won't stick that easily in the sharp corners.


I use chamfers when doing cookie cutters, playdoh cutters and "playdoh toys" for the kids, I also printed custom duplo/lego bricks, brio train stuff - all of them customized to be "round" as it helps with a lot of stuff (like connecting them)

And I use chamfers/"bevels" for other stuff - eg when printing some prototypes for hardware devices at work (holders, "pens" containing electric measurement stuff, ...)
 

Good luck and have fun with your hobby


PS: GfK meanwhile brought up the acetone thing --- as Dabzs wrote, this does not work with PLA. It only works with ABS material - and ABS is harder to print - and it's fuses (when printing) are ---- let's say you better have an open window to not poison yourself


bye
Ron

[Dabz]

- first is the shape of the logo - it is not smooth, it looks like it uses too few vertices (when thinking of polygons) or has sharp edges (vectors...)

No argument there, that was laziness on my part, as I made a model, with a smaller logo on, and "Ex32" underneath, and for that, just nipped the bush off it and whacked it on my plaque template, then scaled it up, which exaggerates things obviously, thought I would just sort the jaggies when dressing the piece... Obviously not! [See attached]

Anyway, that was originally for our Neils bairns to dress up and paint and stuff so he could have it in his office, and, well, still never got around to take the bloody thing over!

- the print shows some issues - like if there was heavy over-extrusion when the "shape" began

I use the slicer that came with the machine, I usually put it to "Hyper" when printing something out... Seems like, erm, I had it on "Standard", doing that triforce print now to see if there is a marked difference!

that sand won't stick that easily in the sharp corners.

Top tip, thanks for that Derron, like I said, I'm learning, playing, only way to learn it to make mistakes and have a bit chew!

I know one thing... I'll not forget to preheat my ignot maker up again... Proper soiled meself when a splattering of molten metal started spurting!

Good luck and have fun with your hobby

Keeps me out of trouble! hehehe

Dunno if it helps but I watch loads of videos like this (3d printed stuff, wood turning, casting, restorations etc) and I've seen people use acetone vapour to smooth out 3D printed things.

Oh, so do I, I love out like that, even got a lathe and frightened meself with it a few times (some videos of it on me channel), proper dodge mind, had a good few kicks from it, even now when I look back at them, it dawned on me I was wearing gloves... Absolute massive no no, but at the time, I just never give it a thought... I was honestly like "Eeeeee f***ing hell Michael man!!!" :/


Dabz

[Derron]

Dunno if it is the light (flash light) of your camera ... but the surface (side, not top) of your print looks pretty "rough" and not "smooth".

On flat surfaces (90° angle from the ground) you should see lines - but they should not "wobble" or be randomly "more or less".
If this happens you might be printing "too fast" (maybe this is your "hyper") or your hotend cannot squeeze out constant flows of extruded material ... or .... or ... or.

Maybe first thing is to print the outlines way slower (infill can be ... ugly if you do not need so much sturdyness). With my old anet I printed at about 80-120mm/s and the result was OKish to checkout the form, the noise was high. When doing "nice" prints for work (so surface should be smooth and shiny and... yeah) I printed with 0.1 layerheight at about 50mm/s.

My geeetech now is less noisy and more accurate (my anet one had a non linear increasing inaccuracy - and you needed to increase all drill hole diameters by half the nozzle size to make them fit... this sucked). Ok so now I print with about 60mm/s and the first layer with slow 20mm/s (for nice adhesion and first layer quality).

I think the surface is rather smooth now. Exception is if I use some older PLA (some is 3yrs open now ...). I only have bought 2 rolls for >30 euro/kg - because we needed stuff at work and they only buy from normal vendors, not ebay, not amazon (strict rule). Personally I just use the 8-12eur/kg PLA materials or ~15 eur PETG rolls. But hmm, think I have still 20+ rolls unused laying in the shelves. Biten more than I could swallow I guess

I once tried with Primer and Glossy Paint ... while I was able to get rid of these small lines (especially on top surfaces) the painted look was ugly. It looked "cheap" - cheaper than the original.


BTW some slicers have the option to "polish" top surfaces - by moving the nozzle over the already printed surface. Might help a bit too. Dunno if the printers software can do it too.


PS: Do not get my postings wrong here - just am trying to help, not nitpicking or "blaming" you of doing stuff the wrong way. It is your hobby, you enjoy it - and if you improve over time, then the better

PPS: I also watch a lot restoration videos the last weeks, even my 5yrs old enjoys when they remove the rust and make stuff "shiny" again (he is a little bit "princess like" there ).


bye
Ron

[Dabz]

Hehehe No worries Ron, there's no offence taken, I know your trying to help matey!

I've printed the triforce thing off, and the edges are really smooth, I mean, there still is lines there, when I rub my fingernail along the grain, its smooth as silk, against the grain, there is a bit of scratching, so they are there, but, they dont seem that deep, but they are there... Its all a bit glossy so I'm thinking the light brings everything up, regarding the top, it's okay on hyper, though, I think you are right, it needs a bit more when it comes to flat bits. I've never really explored my slicers "behind the scenes" options, just, always went for usual shop front options if you get me, but, having a peek, you can indeed set each layers thickness and what not individually, which will be handy to know, and have also seen some options that get rid of extruder travel burr's, it either moves off the print and goes around to get to the next printing point or hops (lowers the bed, moves, then raises it back up), thats handy to know as well!

I should really have a play with them, but, again, its been the time, not until now where I've give myself a little sabbatical I've had a go at getting my teeth into it a bit more, going back to work on the 11th, but then, not sure what will be happening on the sites [building], not fussed really, I've found myself in the lucky situation that all I need is money for bills, no mortgage or anything remotely big like that now, it's not as if I'm going anywhere due to Covid constantly knacking everything up, as long as I can pick up a bit of private work to tick over, I've got a bit of cash I'd hate to break into, because I saved it to do the house up, so, I think I'm pretty much good... Other then that, more time for just me, my printer, a shed and a 1000 degree celsius crucible of sloppy gear! \o/ yay

Dabz