Has any body tried to use a small brushless dc motor as a galvanometer? I took apart a DC brushed motor last night and removed the brushes, I connected + voltage to one of the three windings, used the 2nd one as common and the third to a PWM output and the motor acted like a galvanometer. My wires were too big so it did not move linearly but I will try again with a small brushless as soon as I caby tag16c - Polar Machines, SCARA, Robot Arms
@timogiles , I love the design. Could I see your galvanometer driver circuit.by tag16c - Polar Machines, SCARA, Robot Arms
@A2, how about part of a rubber glove glued to the back of the mirror and streched across mounts I think the center fulcrum would help.by tag16c - Polar Machines, SCARA, Robot Arms
Dino, First moving faster allows movement without turning laser off ie 2 colums not connected. More powerful laser would mean more complicated peice or faster print or finer laser resolution and squarer corners. But this could cost upto $5.00 with driver amps for the coils instead of the .10 for a diode and cap. The microcontroller of choice for me is the PIC 12F1501 cost about $0.75 8 pin dip.by tag16c - Polar Machines, SCARA, Robot Arms
Your design is simple and looks great! Wish I had thought of it.. Maby springs instead of rubber bands. Have you done the math on compensating for the fulcrum on the rear of the mirror instead of the front, (mirror thickness,distance, at the reflected angle) it should not be too hard to do?by tag16c - Polar Machines, SCARA, Robot Arms
A simple clip on the back of the mirror (Made by the printer) on the string could be used to "PUSH" the string to the front face of the mirror to effect a front surface pivot point. This way the string is continous and glued to the rear of the mirror but in the Front Surface Plane for rotation.by tag16c - Polar Machines, SCARA, Robot Arms
This might be a way to make small quick mirror adjustments for both X and Y using audio. Two of the circuits below can be attached to a very cheap (35 cents) microcontroller to allow up to a 20 Khz amplitude modulated sound wave to generate 20,000 X,Y points for laser mirrors at sound card resolution. Any Micro controller (I use Microchip) with at least 5 I/O pins and any Op amp rated at 60Khz rby tag16c - Polar Machines, SCARA, Robot Arms
Removed duplicate postby tag16c - Polar Machines, SCARA, Robot Arms
I have a problem with the Z axis homing. I get 2 different points. In one mode the z motors drive down till the homing switch is made then reverses till the switch opens. In the other mode the z motors drive down till the homing switch is made then reverses till the switch opens then slowly moves back down till the switch is made again. There seems to be no rhyme or reason as to which homing I geby tag16c - General
I powered up my max tonight for the 1st time to test it out. Pronterface can talk to the arduino I can turn on the heaters but the arduino is not talking to pronterface. I can read raw temperature data using my own sketch (usb port) but getting no temp feedback in pronterface. any sugestions on what to checkby tag16c - RAMPS Electronics
Cheap Stepper motors on eBay. Search Nema 17 stepper sort by lowest price Less than $7.00 each and $5.00 shipping for each groupby tag16c - Stepper Motors, Servo Motors, DC Motors
I have been considering what you said about the instability around (0,0). Unless I have made some basic mistake, using the calculations from the attached sheet, that instability should not be a problem, and as long as the Top diameter is less than the base diameter the calculations work great. You do have that nasty Sin-1() table, but it can be in motor degrees (ie. 1024 Mdeg/Circle) so that motoby tag16c - Kartik M. Gada Humanitarian Innovation Prize
BeagleFury () I am new at Reprap so just ignore this if it has been considered and rejected. My drafting skills are as rusty as my mind sometimes. I submit this as a modification to your concept. Some Notes: My statement about the calculations had more to do with relative motor positions than math for two arms. When the base table rotates it changes the part table angle just a little in this desiby tag16c - Kartik M. Gada Humanitarian Innovation Prize
Are you starting a Spinning Topic? I would like to be involved. This seams to have great possibilities. I am just starting to look at the math to convert from Duel disk radians to static XY on the top disk. Hope I can be involved Great and innovative idea!by tag16c - Kartik M. Gada Humanitarian Innovation Prize