Show all posts by user
Page 1 of 2
Pages: 12
Results 1 — 30 of 43
Hello,
I've been running very successful prints for a while now but I ran one today (the only difference between this and the last being new filament) and about 20 layers into the print (all of which were almost identical to each other as the print is mostly vertical) the part suddenly started building with a huge Y offset (~25mm). The printer still believed it was in the correct place.
I didn
by
awmt102
-
Printing
Thanks for the advice. I will try it out and see but I think the design of the Mendel mitigates misaligned rods - the carriage is only constrained on one rod, it floats on the other, so slightly misaligned rods should make a difference. I would also have thought that binding of the carriage or underpowered steppers would be a bit more random so each layer would be misaligned with the last, but my
by
awmt102
-
Printing
I see your point.
To try and find out more I made a simple part - a box 50 x 50 x 1 mm. I then printed 3 copies of the part arranged like so:
Y
--------------------------------
| ___ |
| |1 | |
| |___| |
| ___ |
| |2 | |
| |___| |
|
by
awmt102
-
Printing
Sorry - completely forgot to mention!
It is a Reprap Mendel (cartesian). I use Repetier firmware and Repetier Host so I can change the steps per mm in the EEPROM.
by
awmt102
-
Printing
Hi All,
I'm struggling to calibrate my steps per mm and can't figure out whats going on...
I spent a long time calibrating my X and Y steps per mm with a particular object and thought I had them spot on. I went to print a different object that was slightly larger and it came out completely wrong.
I did a bit of investigating and worked out that I calibrated in the lower left quadrant (close to
by
awmt102
-
Printing
Hi,
Thanks for the replies - although not really answers to the questions I asked. I am well aware of why the holes come out undersized - the list I presented are the proposed solutions to this, including designing the part with the shrinkage in mind (i.e. using nopheads polylines concept). I was actually interested to know if others had had success with Slic3rs 'print external perimeters first'
by
awmt102
-
Slic3r
Hi,
After some reading I have determined that the best advice people are giving to get hole sizes and general dimensions accurate are:
- Make sure the printer is mechanically calibrated
- Make sure the printer firmware and Slic3r are properly calibrated
- Print external perimeters first so that excess gets squeezed into the inside of the print rather than making holes smaller.
- Design holes to
by
awmt102
-
Slic3r
After some investigation I initially found that if I put a 0.1uF filter cap across the Z endstop signal and ground it behave as expected. However, on looking at it today the problem has returned.
Does anyone have any advice?
Thanks
Andy
by
awmt102
-
Repetier
Hi,
I have just switched to Repetier FW and Host. Everything is good so far except for the Z-endstop. I am using Generation 7 Electronics and Gen 7 optical endstops on a Sells Mendel. My endstops in Configuration.h are as follows:
// ################ Endstop configuration #####################
#define ENDSTOP_PULLUP_X_MIN false
#define ENDSTOP_X_MIN_INVERTING false
#define MIN_HARDWARE_ENDSTO
by
awmt102
-
Repetier
Its been a while but i finally got around to trying a few more things:
Reflashed the bootloader - did not help.
Tried two brand new ATMega644p chips (with verfiied bootloaders) - did not help
I then had a minor improvement in things...
Recompiled firmware on a separate machine and tried to program - did not help at first...
Reflashed the bootloader on one of the new chips, setting all empty me
by
awmt102
-
Firmware - mainstream and related support
Hi,
At first I thought this was just happening when changing a few pins (since up until then changing Esteps was working fine), however it is now failing every time no matter what is changed. It seems to me that the bootloader is not working properly. I need to reflash it, but need to borrow a laptop with a parallel port to do this. I will see what happens when I get hold of one.
Thanks
Andy
by
awmt102
-
Firmware - mainstream and related support
Hi,
I am trying to add a fan to my teacup based reprap. When I tried to reprogram it failed with an avrdude verification error. In order to investigate I reverted back to my original working firmware:
// name port pwm
DEFINE_HEATER(extruder, DIO3, 1)
DEFINE_HEATER(bed, DIO4, 1)
//DEFINE_HEATER(fan, DIO14, 1)
and tried to simply swap the heated bed and extruder pi
by
awmt102
-
Firmware - mainstream and related support
I think you misunderstand my issue - the print is not offset from that point onwards, only a single layer is offset before it returns back to the correct (zero offset) position and builds as normal. So I end up with a piece 750 layers high with one single layer jutting out by 1mm.
I will look at my acceleration, but I would expect that if this was a problem it would happen a lot more often than
by
awmt102
-
General
Thanks for the advice but as I said - stepper drivers are well heatsinked and the symptom of a skipping motor would be an offset from that point on in the print, not a single layer that then returns to normal. Drivers are also set to just less than 0.4V.
What do you mean by the acceleration? I thought all firmwares use some form of acceleration? Therefore I must have it enabled. How does this fa
by
awmt102
-
General
Hi,
I am experiencing an odd phenomenon with my Mendel.
Part way through a print (about 75% through) I got a single layer offset in the y axis by about 1mm. The next layer printed properly directly above the first 500 odd layers, as did the remainder.
I have heatsinks and fans on my stepper drivers (in any case I would not expect a slip in one direction followed by an opposite slip of exactly
by
awmt102
-
General
Sorry - didn't clarify - PLA at 180 Degrees.
Printing with a fan is the goal, but of course I need to be able to print the fan duct first. I will try printing slower until I have a fan installed.
by
awmt102
-
General Mendel Topics
Hi All,
I am having an odd problem printer the 20mm calibration cube. Everything adheres to my heated bed OK and I get no curling on the lower layers. However as the build goes higher the corners start curling up a little. This becomes more exaggerated as more height is added.
Can anyone give me a clue as to what would cause this and how to counter it? I will state again that this is not the '
by
awmt102
-
General Mendel Topics
OK,
So I think it was all my fault! Having looked through the code I remembered that for some reason (not sure why!) I modified temp.c by removing the dimension of the temp_table array which obviously results in the code looking in an incorrect memory location and reading the wrong number.
Have not tried it yet but I'm certain that is the problem. Sorry for the confusion!
Andy
by
awmt102
-
Firmware - mainstream and related support
Thanks for the suggestion - I think that was a hangover from early testing where my E stepper was not moving properly so I set it really high, not knowing what the units were and assuming the IDE would warn me about an overflow.
Not sure if you are suggesting my E-Steps per m is also very high, but that is what it needs to be to draw in a metre of filament.
It is a 10k, but I think you misunder
by
awmt102
-
Firmware - mainstream and related support
Sounds to me like your step stick current limits are not set correctly.
You need to trim the little pot on them so that you have enough current to prevent missed steps but not so much current that you overheat the drivers and they shutdown (which also causes missed steps!). On my machine it was quite a small window in which they would operate, I basically wound the current right down then told
by
awmt102
-
Firmware - mainstream and related support
Hi,
I have been successfully using Teacup for a while now. I have both heated bed and extruder thermistors but they are identical so I have just used a single thermistor table and all is well.
I am about to move to using a different hot end that has a different thermistor so I need to have two thermistor tables now - one for the new hot end and one for the original heated bed.
In preparation
by
awmt102
-
Firmware - mainstream and related support
I do not think that is the case for two reasons:
1 - There is infill with this part, its a single walled calibration piece and I am talking about the perimeter.
2 - The model is a straight line 20mm long going from 88 to 108 (minus a small amount for the corner radii) so 0.8.4 is doing the correct thing in making one large move between these two locations with a fixed Y (~0.01mm error only) val
by
awmt102
-
Slic3r
Hi,
I have just upgraded from 0.8.4 to 0.9.1 and when printing a single walled calibration piece noticed that the axes juddered a lot when moving. They still followed the correct line but it was almost as if they zig zagged along it with very shallow movements. Looking at the G code confirmed this:
Here is the 0.8.4 gcode sample for one complete revolution of the piece:
G1 F1200.000 E-5.00000
by
awmt102
-
Slic3r
Hi,
I am just starting to use Slic3r 0.8.4 with macpronterface for printing with my Reprap Mendel.
My machine is all setup correctly and my E steps per mm is correct (extruding 50mm draws 50mm of PLA into the extruder). I use a 0.5mm nozzle. My PLA measures at 2.94mm - I have entered this into Slic3r.
Slicing the 0.5mm thin walled calibration piece calculates that I should get a 0.53mm wall. I
by
awmt102
-
Slic3r
Hi Traumflug,
Thanks for the information on the updated page, I had not realised that it was more about the size of the dremel.
I would love to make a spindle myself, in the vein of the Mantis one. I did find a great article on the internet about making your own spindle but I cannot seem to find it anymore. My problem is that I lack the metal working tools to do it well and it would just end up
by
awmt102
-
CNC Routers, Mills, and Hybrid RepRapping
Victor,
Thanks, but I was after a tool holder for a Proxxon tool, not a Dremel. Dremels are not really any good for milling as the bearings are generally quite poor.
by
awmt102
-
CNC Routers, Mills, and Hybrid RepRapping
Hi all,
I was wondering if anyone here has tried using a Proxxon rotary tool to mill PCBs using their Mendel?
If so would they be able to share their design of tool holder? Reading through the RepRap Wiki somebody has definately made one:
But they have not posted the model file for it. I am not adverse to making my own, but if somebody has got one that works already it would save me a bit of
by
awmt102
-
CNC Routers, Mills, and Hybrid RepRapping
Thanks for the replies everyone. In answer to your questions:
@ brnrd - My feed and flow are both set to 25 - I can't imagine this is a major issue given that pretty much everyone I have read about uses a number in this region.
@ NelsonRap - My fill is more anaemic than bulging so I am sure it is not this.
@ Andrew - My 20mm cubes come out with near perfect dimensions and the walls are not wav
by
awmt102
-
Skeinforge
Hi Everyone,
I am having some trouble getting my holes to print the correct size. I am printing a 2mm high simple ring, ID 22.4mm OD 34mm.
In order to get my ID to the correct size I have to enter VERY high numbers in the stretch page, but this introduces strange 'artefacts' such as that seen in pictures 1 and 2. These artefacts make the diameter of the hole smaller in that particular spot so
by
awmt102
-
Skeinforge
Page 1 of 2
Pages: 12