As this forum has no Hints and Tips section, Tech-Talk seemed the best place to put this - General now seemingly reserved for people with problems with their purchased (non RepRap) printers and Tech-Talk is only read by about three people, but maybe one of you will find it interesting. Spring wire clips are hardly a new way of holding parts to other parts, but it works amazingly well with 3D priby leadinglights - Tech-Talk
There are clear cases of asking questions that have been answered many many times in the history of the forum; but having said that, I don't think that the problem is entirely with the noobs. The combination of really poor search tools in most forums, documentation (wikis, etc.) that are so outdated as to be nearly useless. In the forum some answers to oft-repeated questions so brief as to be ofby leadinglights - General
Those that the gods would destroy they first make mad Those that the organisation would destroy they first make bad Mikeby leadinglights - General
The first CNC miller that I made had all 6 limit switches wired in series (they were connected as NC switches) The controller "knew" which motor it was running and in which direction. Any operation of any of the 6 limit switches except when it was homing that axis would signal an error - machining beyond the limits, broken wire or possibly a screwdriver dropped in the works. The control program fby leadinglights - CoreXY Machines
5mm should be fine. If the contact point is too small then there is a risk of damaging the PZT ceramic while if it is too large much of the bending would be in theo uoter part where there is no piezoelectric material. Your design should work well but try not to let the perimeter of the bed snag on the body part of your supports - as long as there is a little clearance around the edge then a quicby leadinglights - General
Sometimes the specification of the printer leads you inexorably to a particular kinematic. I was approached some months ago by somebody who wanted to 3D scan people to print full size for making lightweight armatures which would be used for making bespoke dummies for shops and other displays. The idea was to reinforce the armature with glass fiber rods and finish them off with about a 1mm layer oby leadinglights - General
Quotepandaym ........... Do you have any video of that two axis bed slinger? Would like to see such a machine working. ................................ The XY mechanism being used for some light milling in The reason why I didn't want to move the hotend mechanism in At the moment it is stripped down to replace the printed gears shown in the second video as they kept breaking. Mikeby leadinglights - General
Hi Pandaym, Having 3 axes working independently does intuitively seem the way to go. For myself I would rather build my next 3D printer from cast iron; filed, hand-scraped, and, if necessary, chewed into perfect flatness and squareness. The numbers however tell a different story: Many Delta printers made by happy amateurs achieve accuracy throughout the build volume not too far from the cast-ironby leadinglights - General
I am investigating a new method of probing the build stage for leveling/compensation and for the Z height of the nozzle (or nozzles). I started on this in the general section of the forum but I think that it should be in this Tech Talk section. To rehash: Underbed sensors have been used and been found reliable as long as the force at which the sensor triggers is fairly high and the sensors areby leadinglights - Tech-Talk
The compliance is not enough to be called loose. There is an old posting at where I measured the deflection with a 500 gram load and got less than 40 microns. That is for a single cell and includes a little compliance for the mounting. As you will be sharing your load between 3 piezos with a simpler mounting I think the figure at the piezos will be closer to 20 microns per kilogram on the bed.by leadinglights - General
For most purposes, you should use the piezo disks in radial mode even though it introduces some unwanted compliance into the system. The additional compliance is usually so little that it can be safely ignored. Compression mode does give a very rigid structure but needs greater care to get it working well. Bending in one axis can give problems with some piezos that where there can be a substantiaby leadinglights - General
A true luxury of questions. I will do my best to answer all of them. @Chowa, The Z-axis is not shown on the chart and the Y-axis is in ADC counts. Having said that, with a Z speed of 2mm/second the 32ms X duration covers a Z travel of 64µm. Z drive is from a 0.9° stepper driving a 1mm pitch lead screw with anti-backlash nuts. The printer is not a Delta but a slightly unusual Cartesian type wherby leadinglights - Tech-Talk
@DC42 O.K., it looks like I will be going 32 bit. Mikeby leadinglights - General
@DC42 Do you mean that RepRapFirmware would be able to do something like the following in G and M codes? Move to a position over underbed piezo sensor Probe with Z carriage touch sensor to get a starting datum Move the first nozzle to that position and get a Z offset for the first nozzle (reading from underbed sensor) Move the second nozzle to the same position and get Z offset for the second nby leadinglights - General
Thinking a bit more about this, I think there is no reason to use an optical sensor as both nozzles can be lifted at the same time and the whole z carriage lowered. A simple microswitch or piezo touch sensor could then be used: The piezo device could easily operate with as little as 1 gram of pressure. The diagram below shows the general idea. The requirement still exists to find a way of gettby leadinglights - General
What is the best or easiest (or even possible) way to automatically get Z offset and bed leveling with two different sensors? Specifically, is it possible to perform a G30 to set the Z probe offset using one sensor and then a G29 to perform leveling/mesh compensation with a different sensor and different input pin? A bit of background and detail:- An under-bed sensor and conditioning board thatby leadinglights - General
As pointed out by the_digital_dentist and ruggb, there is a problem with 4 point leveling. If both the bed and the carriage that it is mounted to are solid then an adjustment is near impossible. If the bed is flexible while the carriage is rigid than adjustment will cause the bed to warp. It is possible to have some carefully calibrated flexibility in the carriage and achieve workable adjustmentby leadinglights - Printing
As far as the cooling of entire parts I can claim no knowledge whatsoever; cooling on one part stopped it from distorting while a similar part warps badly if cooled. I do however have one observation that seems to hold up to test: Cooling the filament slightly immediately after it has been laid down helps to keep fine detail. This can be done with a circular air nozzle or a "Berd Ring" to drop tby leadinglights - General
A 3mm aluminium plate will bend, it is more a matter of how it can be minimized and what residual bend can be tolerated. Having a fairly thick glass plate can reduce the bend but over that area maintaining good thermal contact with any bed heater may cause problems. My take on it is that you will probably want to use 4 supports with that thin a plate and even 4 will be overconstrained and any atby leadinglights - General
I think that I am convinced by the article from Well-Engineered and will add making a titanium heat-break to my backlog of projects. A note to the unwary: Titanium machines fairly readily unless you stop the smooth onward movement of the cutting tool - at this point it work hardens and you would be better served watching a GoT video, drinking a pint of beer and wondering why you started the dumbby leadinglights - General
I think there are two significant problems with mixing nozzles: It takes some time for the filament to be purged before printing can start with the next filament There is little or no possibility to change the temperature, nozzle size and possibly other factors between filaments. While your requirements may vary, I can find few things that would work within these limitations other than multipleby leadinglights - General
I have to agree with MKSA to the extent that many interesting projects never result in feedback to the forum. In trying out new ideas the failures are as important as the successes but only if the details are also published. As far as my gut feeling goes, I would go with parallel, but if the leads on each piezo are extended then both can be tried. On the 4 underbed piezos, mounting a bed on 4 cby leadinglights - General
I also used a flat heatsink as shown below. I did find it an advantage to extend the coupling distance as shown by the bit marked "Copper coupling tube". This photo is of an earlier model and the length of the copper tube was extended then trimmed to get the best thermal consistency across a range of materials. In later models, the tube was hidden beneath a PEEK terminal block so not availablby leadinglights - General
I know very little about skiving as a machining process so won't comment on that. I will, however, comment on the use of copper in this otherwise very interesting design. I feel I am able to give some input in this as I have prototyped a few heatsinks and hotends with different materials. While the thermal conductivity of aluminium is only about 60% of the thermal conductivity of copper, the demby leadinglights - General
Although I have not tried piezo elements in series, I would think that the voltage is additive at any point in time; even if some of them are giving a negative value. As an example, say after 5 milliseconds the outputs are Piezo1 = 2V, Piezo 2 = 2V, Piezo3 = 1V and Piezo4 = -2V then the sum would be 2V + 2V + 1V - 2V = 3V. In this case, if all else is equal, and assuming the amplifier is a voltagby leadinglights - General
I did a bit of research on the temperature gradients in my nozzles some years ago although not nearly as comprehensively as deckingman. I did learn in the process that some "upgrades" were not as good as hoped. All results here are from memory as life is too short to go through handwritten and digital notes. I have attached a drawing of my earliest hotend with a detail showing the aforementionedby leadinglights - Developers
Braiding together twisted pairs would electrically be better than the wide braided cable in the photograph. Cross talk is not reduced as much between the cables in the flat braid but is about as good with when related to conductors not in the braid. The advantages of the flatter braid are in the greater flexibility - in the case of braided twisted pairs, each twisted pair is slightly less flexiblby leadinglights - General
I have tested braiding as shown in the photograph and it is effective in reducing noise. it is also a method sometimes used in low level multi conductor signals cables e.g. ecg or multiple photodetectors. Mikeby leadinglights - General
A method I have found very satisfactory is to braid (plait) the wires. This eliminates the need for sleeving, gives better cooling of the high current (heater) wires, is more flexible than a sleeved or even a naked bunch of wires, has reduced electrical interference as well as reduced fatigue at the wire ends and quite possibly cures scrofula - I like it anyway. The picture below shows braided 7by leadinglights - General
If:- You have many years of experience. You can deduce from available clues as to where the dangerous (live) parts are. You have learned from many mistakes and lots of damaged equipment in the past. You are sure that you have overlooked nothing (like water getting through the drilled holes). You have prayed really really hard to the right God at a time that you believe him (her) to be listening.by leadinglights - General