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Maybe your problem has something to do with thermal expansion?
Do you always wait until the bed is fully heated, before you start recalibrating?
Not that it would change much in the Z height of the bed, mostly XY would scale,
but maybe the printbed flexes as it heats because of uneven stresses in the glass/pcb?
by
FalloutBe
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Mechanics
You are NOT going to get smooth even 20 micron layers
You won't even get smooth even layers at 70 microns
But in my previous post I attached an image, 50 microns and it indeed was smooth! I don't understand why you say it is impossible, if I could do this on a cheap Prusa I3
And I did often smooth my parts with acetone. This makes them look great, but it doesn't change the fact that I want a bet
by
FalloutBe
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Mechanics
Hmm well yes, the Z precision of my XY axis will probably be worse than the Z axis.
But right now I have a terrible Z axis, and I just want to get it as good as I possibly can.
I don't care if my XY axis becomes the worst factor in play. At least I will be happy with my Z axis then.
I attached a picture of what I have in mind right now. What do you think?
It is a 1204 ballscrew
by
FalloutBe
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Mechanics
Quotethe_digital_dentist
How did you print the outside at 50um and the support material at 400 um?
In Slic3r, there is a setting for the infill: "Print infill every # layers", which I set to 8.
by
FalloutBe
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Mechanics
Couplers can indeed be tricky to mount. A lot of times, the screw ends up rotating off-center.
That's why I wanted to buy motor and lead screw in one piece. But hmm.. I'll use a coupler (: In the end, I will be glad to have it in two pieces.
why such a tight layer size?
When the layer size is for example 20(+-1) microns, that means the layer thickness will vary by 5%
I can indeed not see with th
by
FalloutBe
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Mechanics
Alright, not 20 microns then 40 or 50!
The smallest nozzle I have is 0.25mm.
So what about the Z axis? Which leadscrew should I buy?
by
FalloutBe
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Mechanics
Thanks again cozmicray, for all your help (;
I'm going for the cantilevered platform, 4 bearings, 2 smooth rods and a single lead screw.
What do you think will be best?
(delrin nut)
or
(motor attached, regular nut)
or
(motor attached, regular nut, coupler)
?
The delrin nut states to have much better resolution, and it is cheaper.
The regular lead screws all seem to have an 8mm pitch, which
by
FalloutBe
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Mechanics
This is what currently seems like my best solution (see attachment)
4 lead screws, supported mount at the top to eliminate backlash, and pulleys at the bottom, with a bearing to keep it in place.
Motor and bed not shown, just to keep the drawing simple. Smooth rods will not be used, as there will not be much force on the bed in the X and Y direction.
What do you think of this?
If this is good,
by
FalloutBe
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Mechanics
Ok. I will use regular bearings then, and put sone axial force on them to fix the backlash problem.
I did some research on how I need to mount the lead screw. To eliminate backlash, it turns out I have choice between:
- One bearing on each end of the screw, with nuts on the screw that push the two bearings apart. (like this example)
- Two bearings on one side with nuts that push the bearings to
by
FalloutBe
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Mechanics
Alright, I think I'm going to go with 4 lead screws, driven by a belt (single motor).
Do you think I need smooth rods, or will 8mm lead screws provide enough strength to keep the platform from moving?
I also need some kind of bearing, which can rotate but keeps the lead screw from moving up or down.
I have no idea how this kind of bearing is called, can someone tell me please? ^^
by
FalloutBe
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Mechanics
I had a prusa I3, where backlash wouldn't be a problem because gravity would keep the Z axis down.
However, when moving down,
because of little friction on the linear ball bearings sometimes the whole Z axis would "stick" in place, and then fall down after a while.
Ball screws seem Sooo damn expensive!
Oh, and I was looking on eBay for lead screws which have a round end (without thread on it),
by
FalloutBe
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Mechanics
Thank you for all your replies!
Something like this (example 2 of what dc42 has suggested) might be the best solution. 3 or 4 lead screws, driven by a belt and one single motor.
Do you think it'll be necessary to add smooth rods to keep the platform in place?
Or would the leadscrews be stiff enough to keep the platform from moving sideways?
What do you think is the best way to secure the le
by
FalloutBe
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Mechanics
I know (: but it really needs to be thin.
Multiple linear bearings orientated vertically, which are only a few cm's apart, is going to be bad.
The platform will be about 30x30cm. I'd say that needs at least 10cm of spacing in between the bearings.
A cantilevered platform is something I really don't want in this design :/
by
FalloutBe
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Mechanics
"The one that doesn't move"
Haha, indeed (;
But Something has to move in the Z direction. I could lift up and down my XY assembly, which is basically the same (more difficult actually) as moving the bed up and down.
I'm quite stuck now with the idea of "really wanting the bed to be my Z axis" because I am really happy with how well the XY assembly performs.
"A single threaded rod/lead screw"
Oh
by
FalloutBe
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Mechanics
Hello!
I am designing a new printer. The head moves around both the X and Y axis, and it works just fine.
The Z axis is my bed, which will move up and down.
I however have questions about in what way I should construct the Z axis, for it to be very acurate!
After typing this whole post, I realized that many people won't like to read this much text.
You don't really have to, the basic question i
by
FalloutBe
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Mechanics
I have always used black for the preview. It was always perfect for me to view the model, but now it suddenly is very weird.
The green triangles do not stay in the same position on the model, when I rotate my camera.
Even if I just use a simple cube as a model, it has these strange green triangles on the sides.
by
FalloutBe
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Repetier
Hello,
I wanted to try out the pressure advance feature of Slic3r, but I'm having some problems with it:
I usually have set a 3mm retraction (bowden), and it always worked fine.
When enabling pressure advance, I'm getting extractions of about a full cm?! Even when pressure advance is set to only 1.
This pulls molten plastic into my cold end, which makes me disassemble the whole extruder every t
by
FalloutBe
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Slic3r
Hello.
Since I updated my AMD video driver, the 3d preview in Repetier looks really ugly!
I can't see the layers very well anymore, unless I zoom in ridiculously far.
(see attached pictures)
There are these strange green zigzag lines at the corners of the model too. This usually never happened.
It looks like there is no more anti aliasing, however I have it enabled, and the grid on the bed is s
by
FalloutBe
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Repetier
Quotechris33
is the m5 captive at the top they freely to move. if not id try use a lead screws instead
Kind of freely, but not entirely. I used to use M5 nuts to get some tiny pressure on the axial bearings.
However, these nuts were not machined in high quality and the top part of the nut, which should push on to the bearing, was not touching everywhere!
It only pushes on one side, which is why I
by
FalloutBe
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Reprappers
It is a custom made printer. I used all electrical components from my old Prusa I3 and bought new mechanical parts. The frame is acrylic, lasercut.
The XY axis is quite the same as an ultimaker.
The Z axis is something I did not see on other printers, it uses 4 M5 rods which are connected by one large belt.
by
FalloutBe
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Reprappers
I tested with another slicer but the result is the same.
I think my z rods are indeed rotating with more and less resistance every time they make a turn. I tightened the belt, hoping to reduce that effect, but now some part broke and I can't print another, CRAP!
You can see the broken plastic part, the ring around the bearing which prevents the belt from slipping off :/
So basically, the belt
by
FalloutBe
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Reprappers
Quotethe_digital_dentist
Congratulations! You have rediscovered "Z wobble". Please see the article here: on page 29.
I thought this thing was different from regular Z wobble. Check the attached image (:
by
FalloutBe
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Reprappers
Hello,
I have a problem with the thickness of my perimeters.
It has this wavy pattern which has the same pitch as my M5 Z rods (0,8mm) but I have no idea how this is possible.
Maybe the rods were rotating off center, and pulling the bed left and right, but in the cross section (see attached image),
you can see that the walls don't shift around the XY axis, but they simply become thinner and thic
by
FalloutBe
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Reprappers
I'm pretty sure it is your filament! This also happened to me.
I ordered black ABS 1.75 and it seemed to be a more viscous; less 'liquid' as you say, even though it was also just black ABS 1.75 but from another brand.
The filament needed a LOT more force to get it pushed through the extruder. I was kind of supprised that there could be this much difference between brands.
Luckily I could simply
by
FalloutBe
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Reprappers
If the hot end temperature is measured 0ÂșC,
then the heater must be shut off immediately because it means the thermistor wire broke.
Is it possible to set a lower temperature limit for this somewhere?
EDIT:
Can't beleave I really just looked over it in the Configuration.h file My apologies!
by
FalloutBe
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Safety & Best Practices
Updates:
- Added a white CCFL light from a scanner to the front of the printer to illuminate the printed part. Held up by custom printed brackets
- Added a part cooling fan
- Printed a small piece that goes right in between the fan and heatsink of the extruder, because when tightening the screws, the fan was bending
- Printed two clamps that go around the 8mm Z axis rods to prevent the extruder f
by
FalloutBe
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Reprappers
Quotedc42
What do you mean by "fast" - have you a speed in mind?
I was thinking of higher than 200mm/s (this on a 200 to 50 micron layer height and with a 0.4mm nozzle)
Quotedougal1957
Try the E3D V6 nozzles go from 0.25 up to 0.8 and with a thermocouple (As supplied by RepRapWporld) is capable of going very hot but 290 as std is easy as well.
The Volcano is a modification to the E3D V6 by the
by
FalloutBe
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Reprappers
Hello,
I want to buy a good hot-end for fast printing for 1.75mm filament and +-0.4mm nozzle.
Am I correct if I'm looking only for hot-ends which have a long heating length?
I also want to be able to print Nylon with this, so high temperatures are also a must!
I found the pico hot-end; it has a long heating area which should help for fast printing. However it seems to be quite expensive.
The E3
by
FalloutBe
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Reprappers
Ah thanks for all the replies!
I just followed the assembly manual that came with my 3d printer;
so basically they connected the hot end fan to the pins that were intended for a part cooling fan :O
I'll change this, thanks for the suggestion MindRealm! It'll be a lot better if it is always on.
Oh, and G code controlled 12v also seems awesome!
by
FalloutBe
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Reprappers
Hello,
Because I'm printing quite a lot of parts, and because I don't always want to wait for the heated bed to warm up,
I chose to leave the heaters (both bed and extruder) on after a print has been completed.
However, the fan just above the extruder heater (the fan which cools down the metal block, where the extruder heater is mounted onto)
always stops spinning after print completion! This i
by
FalloutBe
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Reprappers
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