3D printer silliness

honegod

honegod

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since hardly any sporty stuff is made for my Yaris, printing what I want seems to be my option.
I need a printer for that.
"as good as a Prusa" being high praise, a Prusa i3 MK3S looks to be the ticket.

where do I buy one from ?
czechloslovokia ?
 
I'll be. I was certain they had a US distribution center.

Their orders are pretty lengthy as well.. 7ish weeks out from even shipping.
https://help.prusa3d.com/en/article...40.1921575268.1594149981-513316073.1594149981

Though, in theory, fast ones the thing heads out.
Choose your delivery method

Fedex MK3 Fixed USA
2-3 days, (special discount for MK3S/MINI kit only)
$50.32

DHL Express worldwide
DHL Express worldwide, 2-3 days (USA), 3-5 days (rest of the world)
$57.41

UPS Expedited USA
UPS Expedited, 3-5 days
$78.43

UPS Express Saver USA
UPS Express Saver, 2-3 days
$113.65
Click to expand...

Pretty sure they are the only suppliers of their printers. Unless you hit up fleabay or FB marketplace to find a second hand one.
 
I created an account, made out an order, placed the order.
prusa didn't like my mastercard {personcard ?}.
so I emailed them.
3D printing IS an inherently complex endevour.
 
After traveling is OKed I'd suggest you stop by the SeeMeCNC factory there in Indiana. They manufactur the best Delta style printers in the world.

A Prusa is what is commonly called a bed slider or Cartesian style printer.

https://www.seemecnc.com/

They also make one of the largest printers for sale in their Part Daddy design.

if you want to see printer silliness. :)
 
since I want to print stuff for my car I need to consider heat resistant plastics, which want a consistant high temperature print environment.
so enclosure design begins to interest me.
the ikea lack table design looks popular but has shortcomings that trouble me.
it's flammable, wood and plastic.
borosilicat glass door, aluminium extrusion frame, sounds better to me.
the prusa Bear frame kit appeals to me.
I just started to think about how the bear frame could easily bolt to a enclosure frame.
a well filtered recirculation fan, that is rated for 200c+ ambient, being nessisary for a dust free printing environment, shall not be infringed
copper heatspreader between the heated bed and the flexy print surface to reduce temperature gradients across the first layers contact area.
with a brutally rigid frame there might be a benefit of rubber mounting a massy slab of something, concrete, to damp vibrations.
if the frame assembly doesn't ring like a well tuned katana it is not done right.
 
Copper moves heat quickly, but that also means it cools quickly (=hotspots). It would be good for spreading the heat out, but for even and consistent heat you'd want a good insulator (like glass, ceramic, or black iron).
 
I do not understand where the heat energy is going, where is the cooling coming from ?
I see 2 fans on the print head, one for the cold end of the tip, the other for the part being printed, neither should mess with the bed much.
I figure a chunk of the enclosure function is to keep random air currents at bay.
the spring steel print surface plate would act as an insulator to slow heat loss from the copper layer.
 
As far as enclosures, since some of the extruder fan parts and axis motor holders and things are 3d printed it is kind of important to not add a heater. For the most part the PSU and other electronics will be fine in a basic enclosure which might keep the inside air around 35°C or so...but if the internal temperatures are really warm it's probably a good idea to at least pull the PSU outside of it. Prusa mentions temperatures 40° to 50°C shorten the life of the PSU. For the older Prusa printers you may need to print a reinforcing bracket to mount in place of the PSU since it adds some support on the older printers.
I wouldn't worry too much about a temperature gradient between the heater board through to the spring steel bed itself - it heats to pretty quick and then the printer does a quick hunt/dance to locate the bed height, and this probably lets it equalize before printing starts. And prior to the spring steel sheet...the Prusa i3 MK2S and prior bed heaters used to have the PEI directly on the PC Board heater so there were areas with the PEI only over screw heads and not heater material - as far as I know there were no problems from that, and I didn't notice it. On that old heat bed it was possible to get gradients from the hot end placing the plastic onto the heated bed where you could trip an over-temperature error for the bed if you were extruding over the temperature sensor in the bed - I haven't had that in the i3 MK 2.5 spring steel bed. In the i3 MK2.5 / i3 MK3 (and S models) you do need access to the heater layer itself for axis calibration, and then the spring steel sheet goes on for the quick hunt of bed height prior to printing. Also a lot of slicer software will adjust bed temperatures for the first layer - e.g. some of my ABS profiles have first layer at 100°C then it bumps up to 110°C for the rest of the print. Reaching 110°C sometimes needs an enclosure on my i3 MK2.5.


I had not heard of the bear frame kits, but I'm not liking the center upright area being joined together with several pieces...I'm kind of a fan of the Prusa being a single sheet that has threaded holes and notches in all the right places. My general opinion is you don't really want the parts that define how your axes intersect to be too freely adjustable, and extrusions with side plates and other hardware that mounts anywhere along that rail is in that territory. Some issues can probably be calibrated out fine with the Prusa firmware (in the bear frame kit FAQs it mentions an extruder height difference that calls for using older or 3rd party firmware) but I think you might have to be prepared to spend time fine tuning things with a good supply of measuring tools if say the Z axis (upright frame) pieces end up skewed (vs the relatively flat Prusa plate) and also not perpendicular to the build plate. I think it would be helpful to get used to the stock printer first, especially since it looks like you'd have to do the stock build first to be able to print the parts for the bear frame kit.
 
Image4.jpg


I took this snapshot, cropped it, and came here to do a post on how I would like a third option of high temperature printed parts, and read your post.

Tim_axe said:
things are 3d printed it is kind of important to not add a heater
Click to expand...

bootstrap problem, eh ?
that is what capitalism is FOR.

Tim_axe said:
fine tuning things with a good supply of measuring tools
Click to expand...

yes.
I watched a Bear build video, he used a tape measure to align things.
it hurt my soul.
I am looking forward to using heated micrometers, calibrated with heated standards, to align the heated assembly to get it to work right at temperature.
(in a previous incarnation I used that technique to finish hone a propeller shaft bushing for an airctaft carrier to size and shape, so I know where to find BIG micrometers.)

the heatspreader thing ocurred to me upon seeing Flir pictures of blotchy heated beds.

i saw a video about cable drive remote motoring of non Bowden filiment feed head.
that kind of thing would get all the stepper motors out of the heat zone.
I already have some high temperature silicon wires that I am looking to swap for the stock stuff, particularly the wires that have to move, which should also, slightly, reduce drag on the steppers.
 
honegod said:
I took this snapshot, cropped it, and came here to do a post on how I would like a third option of high temperature printed parts, and read your post.
Click to expand...

That's some timing on the screen shot, I didn't see that option on the first site I pulled up (all3dmakers).

Either way it looks like you would get the fun of assembling the printer, even if it is one time with all of the pre-printed upgrade bits, or twice if you do the stock build and decide to go through with the modification. And since it doesn't appear to touch the extruder, you still get some of the fun of staring at all of the plastic, metal, and wire bits and eating gummy bears. The hot end is really interesting in how the plastic printed parts can be designed to attach everything together, so it might help give you ideas when you're designing parts.

honegod said:
it hurt my soul.
Click to expand...

I'm basically with you. I was thinking this should at least have 1-2-3 blocks or a toolmaker square and clamps to try to hold pieces...and a quick look at the assembly instructions seems to show words like "machinist precision square" etc.

honegod said:
the heatspreader thing ocurred to me upon seeing Flir pictures of blotchy heated beds.
Click to expand...

I had to go look up some of the FLIR/thermal video reviews of printer heat beds after that. The screws show up quite cold on initial heat on the bed without sheet, but its averaged out ok with sheet in place. Before some of the firmware safety timers were added, there were videos of people using the heat bed as a Sous-Vide / water warmer / etc. I guess you have to do whatever gets the video clicks.


At some point you'll have to jump into the software side of 3d printing to be able to get parts out, like the slicer that takes the model and uses filament profiles to generate the G code that runs the machine. Or the CAD side where you'll do the measuring and modeling to make parts that fit.
  • I'm using the Prusa Slicer (used to be called Slic3r PE among others) https://help.prusa3d.com/en/category/prusaslicer_204
  • For design I generally use FreeCAD, though it takes some getting used to vs 1st party commercial CAD software https://wiki.freecadweb.org/Download
    • To get the exported STL file to have good resolution there are some simple hings to configure...but the software hides the panel with needed options until you're in the correct module...

Anyways happy prototyping. If your parts in the easily attainable ABS and/or PETG/PET+ materials work out but you find you do need better materials, you can always look into some of the online 3d print services that use the industrial machines to plop out Ultem/PEI parts. But you probably don't need to do much special to just get setup to print stuff.
  • For my boat trailer I've had good luck with ABS so far, and have abused PVC pipe cleaner / PVC pipe cement to glue my ABS parts to PVC pipe.
  • On the boat I use some PET+ (discontinued) to have some nubs screwed to the deck for aligning a portable plastic gas tank so it doesn't slide around.
  • I have a few simple plastic copies of segments of stupid things to help fit check other parts I'm designing so I can stay inside and not have to find the thing just to check parts on it.
  • For indoors stuff I've had surprisingly good luck with PLA for making handles for dressers when I find the hole spacing is a goofy inch number that makes sense in mm, but isn't carried in stores
 
Tim_axe said:
online 3d print services that use the industrial machines to plop out Ultem/PEI parts
Click to expand...

wonderful.
I can keep my machine closer to stock, prototype what I want in cheap easy PLA, and send the finished specs off to the folks with the more expensive machinery.

random thoughts

sealed tub with dehydrator packets, bowden to mmu, dust wipers
hard mount frame to concrete mass block
bed level with bubble level
copper plate adds moving mass
ups connection, auto shutdown
titanium for thermal expansion minimization, less moving mass.
Aluminum Alloy 6061 23.6
Titanium Alloy Ti - 5Al 9.4


triangulation
bore sights for belt alignment
ducts for motor cooling
 
"bed level with bubble level"

sounds doofy, not so much.

'bed leveling' in 3D speak means telling the print head what the shape of the bed is.
here I am talking about leveling it like leveling a shelf on the wall.
I do not think the Prusa messes much with tweaking the bed level mechanically reletive to the frame, focusing more on the head/bed relationship in software.
excellent, but the whole thing could be sideways to local vertical, put it on a table with a tilted top.
I think having the whole thing aligned with local gravity is a good idea.

the Black Box arrived. Joy !

BB1.jpg


lots of rattling chunks of metal inside, Dread.
 
the rattling noise came from me resting the Black Box on handrails as I lugged it to the apartment, the handrails were doing the rattling, not the BB.
Dread abated.

RT
mount a stationary aluminium heat reflector below bed heater, but it heats the slider bearings too.

Bear kit, with printed parts, on order.
Dark Blue anodised.
 
cleaning bearings with isopropyl alcohol would work better if the fluid was heated.
get the juices zooming around and stirring stuff up at the molecular level.
but iso boils @ 180°f and explodes shortly therafter.
so don't boil it, but DO execute the operation in a pressure cooker.
the pressure in the sealed pressure container shouldn't get too high for the container to contain.
math time.

google
vapor pressure of isopropyl alcohol at 120°F
first hit
https://www.engineeringtoolbox.com/vapor-pressure-d_312.html
"The vapor pressure of a liquid is defined as the pressure exerted by the molecules that escapes from the liquid to form a separate vapor phase above the liquid surface."
yep, now for numbers.

squirrel !
beer2.jpg
 
getting the frame assembled all square has been on my mind.
it occurred to me that it is not the frame that needs to be square, it is only the rods that the bearings ride on that need to be planar and parallel.
the frame just needs to hold the rod mounts solidly.

a Starrett 18" X18" X 4" pink Granite grade B surface plate only costs $500.
but it weighs 150# .
so although it would be excellent for getting the frame assembled square AND it would be a nice mounting base for the completed printer, I do not want to have to carry it around.
plus I am not sure the table I plan to put the printer on would support it for long.
 
Along the line of surface plates, I was at one point looking at import options. For my Prusa i3 Mk2.5, I could probably do a smaller 12x18"...however a ~$50 from Shars 18x24" Grade B, 3" thick (no ledge - these are thinner/lighter) would end up with starting just over $100+ for UPS Ground (from their location in Indiana to where I am a few states over). Getting one with a ledge and the extra thickness (weight) pushed into freight territory and I didn't try to get quotes there. For the Shars options, most of the better grades are the thicker ledge style...I suppose if you were not too far from their location (St. Charles, IL) they offer pick up.

In the end I just got the rods close to square in their holders (12" calipers for across ~7", tape measure for diagonals ~15"), and for the older Mk2/Mk2.5 models the center plate needed to be adjusted (12" calipers for diagonals ~12" front half, ~9" back half) since the distances were set with all-thread. In the Mk3 I think those are pretty well machined lengths on aluminum channel, and the lengths of pieces are staggered to have the center plate in the right spot.

I did build a wood and insulation enclosure / box (including wood bottom/floor), and for a while it was on a fairly level and flat 3/4" plywood shelf in my shed. I moved a while back so now it is on a plastic modular shelf which has an obvious bow from the weight. I think I had to re-run the first layer calibration to tune if after the move (https://help.prusa3d.com/en/article/first-layer-calibration_112364) but at some point I upgraded my Mk 2s to a Mk2.5, so I did eventually redo the XYZ calibration (https://help.prusa3d.com/en/article/xyz-calibration-mk3-and-mk3s_112351). That upgrade was a pretty significant change...so I can't really compare if what the box was sitting on made a difference to the prints. But if I could I'd put the printer back in a shed so I don't have to smell it.
 
Weight Of Granite
1.555 ounce per cubic inch ...
1 ounce is equal to 0.0625 pounds.

I think a 1" thick piece of granite 16" X 16" ( 25# ) would do fine for this.
folks who make granite countertops should be tooled up to make one with a reasonably accurate surface.
a slab 16x32 (50#) might be big enough for a MK3 and a Mini side by side, any reason to not put them both in the same enclosure ?
the Mini would need to be on the left so the spool could be outside the box on that side.
I guess there WOULD need to be a partition to keep air temperatures separated for different materials per printer.
(I get (16)2 from the box that the MK3 frame parts come in from Prusa.)

Tim_axe said:
diagonals ~15"
Click to expand...
so an 18" vernier caliper should be big enough, excellent.

18 caliper.jpg


in that vein, Shars looks to be about a 3 hour drive in my Sport Yaris.

Tim_axe said:
so I don't have to smell it
Click to expand...
yah. the apartment bathroom has a external vent in the ceiling that I think I can rig a nondestructive duct to from the printer box.
I wonder what sort of pressure differential between apartment internal ambient and outside wind across the roof I will need to contend with.

yes, I ordered a Mini from Prusa earlier this week.
 
Tim_axe said:
FreeCAD, though it takes some getting used to
Click to expand...
you got that right.
I am sure it all makes sense once I figure out how to look at my prospective 'thing' from the correct perspective, but finding out what that perspective is appears to be non trivial.
youtube helps with what buttons to press but the explainers tend to assume I share their perspective on WHY since it is so obvious to them.
fine, I am sure I'll figure it out.

I ended up using the bathroom mirror as my flat surface to check the Prusa i3 MK3s level, it was satisfactory and I completed my first Benchy with no significant flaws.

20201024_025014[1].jpg


perfect it aint, but definitely good enough.
20201102_115639[1].jpg
 
That's an odd looking hot end with those teethy looking wraps.
 
the video started freaking me out a bit when he fired the printer up and V the V started jumping around on my 65" oled. had to post.

the shift knob of my 6 speed Yaris is in the wrong place. so as a learning project I am figuring how to Print a more suitable replacement.
I could get a program for artists and sculpt one with the wacom, or a program for engineers and type in all the numbers.
I ended up getting STL files from thingiverse for a Tundra and a Miata knob.
the tundra knob is the right shape and has the right shift pattern engraved, but the threads are wrong. the miata has the right threads.
so far the program that does what I want in a streightforward way is microsoft 3D Builder.
it popped up as the first choice to open the STL file.

1 put the miata threads in the tundra knob.
carve away all of the miata knob that wouldn't fit inside the tundra knob, superimpose the two and merge.
I used Prusaslicer to step through the layers and make sure everything was mechanically sound.
it printed fine, the internal threads are crisp.

I printed it in PLA , which is strong but heat sensitive so the test units will work well enough for testing.

it is the right shape and puts my hand where I expect.

But, it weighs nothing and I liked what the 1 pound knob did in the stock position, so that has to be fixed.
the stl knob from 3D builder is solid, Prusaslicer generates a shell and fills the interior with reinforcements.

2 add mass.
create voids for weights internal to the knob.
3db can do that, I have a bunch of coins handy, dimes fit the best.
 

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Prusaslicer can pause the Print, I can install the 54 dimes, glue them in place so they don't rattle, and resume printing.
 

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the numbers are carved into the knob, and big enough that the top of the knob feels rough.
so I filled them in with epoxy of a contrasting color.
after sandpapering off the rather crude print lines, I printed the knob at .30 "draft" setting so the layer lines were prominent.
 

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If you get a final version you may look at molding the part in silicone and casting it in resin to get that final weight you want.
 
that knob works but is still too light.
1 pound of 1/4" Lead wire arrived.
in 3dbuilder I hollowed the knob completely, with a 4mm shell.
Prusaslicer saw the interior void as a solid and wanted to stuff it with infill, I told it no.
it also wanted to infill the inside of the walls, but increasing the number of perimeters filled that in, plus strengthened the construct.
instead of pausing the print, this time I cut the knob into an upper and lower bit, and printed them that way.

the notion is that I can shape the lead to conform to the interior volume, maximising the volume of lead with a minimum of wasted space.
the top bit checks that the lead doesn't project into the next layer, crashing the nozzel.

the notion is to use this prototype to shape the lead so I can pause the "real" print, add and glue a layer of lead pieces, resume printing, pause again add layer, etc.. and end up with a lead filled solid.

I think a "raft" might be a good idea because the printer is a "bed slinger" and yanks the knob back and forth, possibly ripping it off the bed what with its small base and weight up high.
the 'Dimes' knobs had no problem without one but the 'Lead' is noticibally massier.

the crude stuffing has so far got most of the lead wire coil into the shifter knob, I think a bit of refining of the shape of the very malliable lead wire will let me fit most all of the remainder.
 

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modi123 said:
If you get a final version you may look at molding the part in silicone and casting it in resin to get that final weight you want.
Click to expand...

I am leaning more toward printing the final version in Nylon.
I have been looking at epoxy resin casting tech, mostly to see how well it would generate me a flat surface. table top casting stuff.
but the point of this exercise is to learn how to 3D print whatever I can dream up to use the tech to my advantage and joy.
 
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