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Re: Z-axis threads accuracy in prints - 8 years ago

Can you PM me with the Ontario Supplier? Thanks, -Rob A.

by RobA - General

Re: cant print proper circles - 9 years ago

Sorry - I messed that up - I was too quick glancing at your diagram. It is Y backlash. So all the same things but on the Y axis. See the attached diagram I generated from a spreadsheet model of backlash. This was for a backlash of 5% of the radius. (i.e. a 20mm dia circle would look like this with 0.5mm of backlash in the system). If anyone wants to play with it I've uploaded the spreadsheet

by RobA - Printing

Re: Adjusting Z zero during printing. - 9 years ago

QuoteChri Best way is to modify your printer so Z uses only one Stepper and Disable Z-hold, then you can adjust your heigh as you want, that especially helps when printing very small and thin layer Chri I have an original mendel (one z stepper and a belt) so that is exactly what I have the luxery of doing. I always leave my z slightly high and then manually lower it to just the right height w

by RobA - Printing

Re: cant print proper circles - 9 years ago

Quotejaques That's a very good explanation, and something I was thinking about myself before. However, I've made the belts as tight as possible (more causes binding) and as loose as possible. Results are the same. I also don't notice any slack on the belts while printing those parts. I've also printed the same circles at 50% and 150% speeds with the same results, if this helps. Could it be a p

by RobA - Printing

Re: Heated Bed Relay - 9 years ago

I just use an off-board IRLB8743 with its own power feed. -Rob A.

by RobA - Developers

Re: Made a new linear bearing - 9 years ago

You have reinvented the original Mendel which used this idea for all its bearings -Rob A>

by RobA - Mechanics

Re: Long linear rods - 9 years ago

QuoteMiertam Would a 3 axis bearing like a roller coaster wheel work in this situation? You could use thiner rods/tubes with support welded to the back. If you used tubes you could make the supports do double duty as connectors allowing you to create a linear run as long as you want. Thanks Mike That's how the original mendel was set up. No linear bearings. -Rob A>

by RobA - Mechanics

Re: Better Cooling For Deltas - 9 years ago

Rather than a fan, how about just a pump (like in a compressor), into a accumulator tank that then feeds your blower hose? Something like a reciprocating piston pump driven by a crank, combines with a couple of valves (marble+spring, diaphragm flap, etc.) -Rob A.

by RobA - Developers

Re: MINTEMP triggered - 9 years ago

I was having an intermittent MINTEMP triggered error as well. Turned out to be cross-talk from the extruder stepper wiring and the thermistor, which I was able to see by putting a scope on the input to the board, I replaced the thermistor wire with sheilded twisted pair and have never had the problem again,. -Rob A>

by RobA - Reprappers

Re: circles aren't circles - 10 years ago

(American) Football shaped circles are a sign of mechanical backlash. Either as tleneel suggests belt(s) too loose, or a pulley is slipping on a motor shaft. -Rob A>

by RobA - Printing

Re: making circuits with conductive glue - 10 years ago

This came out in November: And the company can make custom inks: -Rob A>

by RobA - Paste Extrusion Working Group

Re: Skewed print of gear wheel - other prints OK - 10 years ago

I answered in your other post. This is a sign of backlash in one or both axis. You would see the same oval shape printing any circular object but it will not manifest when printing cubes oriented on the axis as you can "calibrate" out the backlash. -Rob A>

by RobA - Slic3r

Re: genarating surface from game maps - 10 years ago

I wrote a gimp plugin to export dat files that the surface command can utilize: but that surface you linked to does not look like a useful depthmap (heightfiled) rendered output attached it looks more like a normal map or an edgemap. -Rob A>

by RobA - 3D Design tools

Re: Skewed print of gear wheel - other prints OK - 10 years ago

This is backlash on one (or both axis). Check that your belts are adequately tight and there is no slop in them. -Rob A>

by RobA - Mechanics

Re: How to get non-porous print and minimize drooping perimeters - 10 years ago

It looks in the first picture that you have a backlash problem causing alternating infill lines to be spaced apart and together. I've cropped and drawn what it looks like (attached) If you do have backlash causing this (I did on my printer) you will have tremendous problems getting the infill both non-porous and not globby/overextruded. -Rob A>

by RobA - General

Re: Pronterface heatbed temps showing strangely... - 10 years ago

I was having the same issue on my hot end. I replaced the thermistor wires with shielded twisted pair, and added a tantalum capacitor just before the ramps board, and the drops have all gone away. This was after throwing a scope across the thermistor line and seeing how bad the noise was... -Rob A>

by RobA - Reprappers

Re: modeling software with slicer but without Gcode - 11 years ago

Slic3r has a SVG export option for DLP. -Rob A>

by RobA - 3D Design tools

Re: Why would my hotend shut off after 5 hours into an 8 hour print? - 11 years ago

You could add a post-processing script to slic3r to reset the temperature every Z move.... bit kludgy, mut it might help. STF for "slic3r post processing" for examples. -Rob A>

by RobA - Reprappers

LCD/Button controll and SD on RAMPS 1.2? - 11 years ago

My printer has an older RAMPS 1.2 Is there any way to connect an LCD display + rotary selector knob plus SD card reader to this board? Thanks- -Rob A>

by RobA - RAMPS Electronics

Re: New to 3D Printers - 11 years ago

Scubasteve23 Wrote: ------------------------------------------------------- > Well I have made up my mind and I am going to go > with the Eckertech Printer the Ecksbot. I really > like that they have created a soild version of the > Prusa Mendel and incorporated the best parts of > the Mendel. Also the support that I will receive > will be better than any other dealer I have spo

by RobA - Canada, Toronto RepRap User Group

Re: Painter bot (based on Reprap/ Eggbot?) - 11 years ago

How about something like this: -Rob A>

by RobA - Let's design something! (I've got an idea ...)

Re: 120degC MOSFET, huge voltage drop on MK2 heatbed - 11 years ago

I switched to a IRLB8743 and can get away with a 1cm2 heatsink with no fan, and it remains touch cool. -Rob A>

by RobA - General

Re: Wood Plugin for Slic3r? - 11 years ago

There is a varient written in python as a post-processor for Cura: (from this page: ) Maybe thios could be called with the postprocessing scrip option? -Rob A>

by RobA - Slic3r

Re: Smallest nozzle ever? - 11 years ago

And depending on the slicer you use, there are often options to infill every X layers. This lets you reduce perimeter thickness while keeping the infill extrusion thicker so it spans better. -Rob A>

by RobA - Printing

Re: Does what I'm looking for exist? [Looking for a 3D Printer] - 11 years ago

The Ecksbot by eckertech might be at the top of your price range but is a solid, easy to assemble kit with a fairly active developer. -Rob A>

by RobA - General

Re: OpenSCAD file import help needed - 11 years ago

Look at any of the provided examples (i.e. example007.scad) You need to extrude the imported file to get any geometry. -Rob A.

by RobA - 3D Design tools

Re: 2D bmp to 3D conversion... How do you do it? - 11 years ago

Jasper1984 Wrote: ------------------------------------------------------- > Stupid question: How do i use it? According to the > wikibook, i must 'simply', but one does not > simply. Frankly i am also against simplying. Assuming you have gimp with python support installed, just save the file as openscad_surface_export.py in your plugin folder. Then after creating/opening an image, per

by RobA - 3D Design tools

Re: Y Axis Freaking Out Randomly - Mendel - 11 years ago

Along those lines, I also had an issue when the stepper wires were bundled with the endstop wires. There was crosstalk that was creating false endstop events randomly. -Rob A>

by RobA - General Mendel Topics

Re: poor 1st layer, can anyone suggest what is wrong? - 11 years ago

I'll second Clem's suggestion. If you have a HPB there is no need to use tape for PLA. Just keep the first layer low and slow. Depending on the PLA I use, my HPB is between 60 and 90 degrees and gets a good stick. Also, If you have a fan (recommended) blowing on the printed piece to minimize curl-up, don't turn it on until after the second or third layer. -Rob A>

by RobA - General Mendel Topics

Re: 2D bmp to 3D conversion... How do you do it? - 11 years ago

I wrote a python export plugin for gimp to generate openscad surfaces : here is a grab of a heightfield source image and the resultant image in openSCAD: -Rob A>

by RobA - 3D Design tools