The U Clamps shown in the McWire pictures seems to be the kind of bracket commonly used to attach a metal plumbing pipe or electrical metal tubing to a wooden beam. They are variously known as "pipe hanger", "pipe clamp", or "pipe strap". Look at plumbing suppliers.by JohnWasser - Reprappers
I think the Mountain Switch encoders are based on mechanical switches and designed for very slow operations such as a mouse scroll wheel. I expect you will need to provide debounce logic on the switches and, therefore, not be able to turn them more than a few revolutions per second without missing pulses. Good luck.by JohnWasser - Controllers
James Switzer Wrote: ------------------------------------------------------- > The full specs are here : > "NO PVC, VINYL or POLYCARBONATE" Looks like BitsFromBytes drawing "cartesian-bot-5mm-laser-cut-acrylic.dxf" (the main sheet of acrylic Darwin parts) fits on an A2 (420 x 594 mm) sheet. This translates to 16.5" x 23.4", well within the 20"x32" capability of the Olin laser cutter.by JohnWasser - Massachusetts, Boston RepRap User Group
Good news for the No Computers Attached! lobby. Zach Hoeken (of RRRF fame) has developed an Arduino work-alike based on the larger ATmega644P chip. This provides four times the programming space, four times the RAM, and 12 more I/O pins than the Arduino Diecimila. The blood-red board is named the Sanguino: I bet the additional pins could be used to drive an LCD screen, keyboard, and SD cardby JohnWasser - Controllers
mimarob Wrote: ------------------------------------------------------- > I get the following hex string over and over again: > 54 sync > 51 HDB2 > 31 HDB1 > 08 dst address Extruder (!!!) > 00 src address PC > 00 version command > BA crc > > The strange thing is, dst address is the address > for the extruder, still the circuit and Java > program work when I conby JohnWasser - Controllers
dtmoi Wrote: ------------------------------------------------------- > I have been looking at controllers and it seems > that the Arduino with a motor shield can only > control 2 servos or 4 dc motors (assumption please > let me know if I am mistaken). The limitations you mention would be limitations of the "Motor Shield" you are looking at. The Arduino has 13 digital I/O pins andby JohnWasser - Controllers
One thing I forgot to mention was the appearance of a pre-release "Sanguino" (http://sanguino.cc/). It's an Arduino work-alike with an ATmega644P processor giving it more I/O pins and memory space. An Arduio Diecimila is almost maxed out by the I/O requirements of the Darwin and the size of the current Single Arduino firmware. The larger processor would provide room for further expansion. Iby JohnWasser - Massachusetts, Boston RepRap User Group
It seems to be working for me. I downloaded the 1.3 firmware, opened Single_Arduino_SNAP.pde which started up the Arduino "0011 Alpha" development environment. I was able to download the program to the Arduino Diecimila. I got a "Can't determine program size" error the first few times I verified (compiled) but after downloading to the Arduino that error did not repeat. When I run the serial moby JohnWasser - RepRap Host
I had a good time at the gathering at Olin College. I had to leave by 5:00 but fortunately the software glitches were worked out and the RepRap Darwin started printing around 4:30 so I got to see it in action. The machine was a joy to behold. Most of the custom parts are currently made of wood which, from what I gather, was cut by hand with a scroll saw. The Z-axis limit switch flag was a gifby JohnWasser - Massachusetts, Boston RepRap User Group
Noon works fine for me. I'll bring my Arduino Diecimila along in case anyone has not seen one yet.by JohnWasser - Massachusetts, Boston RepRap User Group
dwbowen Wrote: ------------------------------------------------------- > A small window appears labeled progress. In this > window the message: > "Waiting For Extruder To Reach Working > Temperature" with a reading of the current temp. > Is this what you are referring to as a debug > message? Sprinkled around the sources are calls to "Debug.d" which appear to be displaying moreby JohnWasser - RepRap Host
Arthur Wrote: ------------------------------------------------------- > Hmm, confusing. But here's the mcmaster > description for the screw > Funny > that in the "part lister > the "Self Tapping Screw 10-24 x 3/4" points us to > the 1/2" version of the 10-24 screw. Oh well, I'm > sure either length will work. The 10-24 self tapping screw lists a recommended drill size oby JohnWasser - Reprappers
dwbowen Wrote: ------------------------------------------------------- > When I tell the software to build the > 10mm-cube.stl found on the website each axis goes > to its home position. I then receive a message: > "Waiting For Extruder To Reach Working > Temperature" > and the temp reading slowly creeps up. When it > reaches only 150 it them begins to attempt to > print,by JohnWasser - RepRap Host
sid Wrote: ------------------------------------------------------- > ABS density 1040 to 1120 kg m^3 > 230x230x100 mm is 0,00529m^3 thats about 5.5 to 6kg I think what he meant to ask was the mass of ABS he would need to make the parts for a Darwin which has the standard working volume of 230x230x100 mm, not how much to fill the working volume. This came up before in and the answer thereby JohnWasser - Reprappers
Andromodon Wrote: ------------------------------------------------------- > ... I STILL don't know how to put my name/address > on the RepRap Map. Click on the "Edit" button just above the description of the map. Navigate to your location on the map. Right click (ctrl click on a Mac) on the map and select "Add a placemark" from the pop-up menu. In the "Title" edit box put your identiby JohnWasser - General
Are you talking about the Tom's RC SC-8000 8-channel USB servo controller? If so, read this: You use the bits in the mask to specify which of the 8 RC servo channels you want to control. Each control message can separately control any combination of the eights servo channels.by JohnWasser - Mechanics
Joshua Merchant Wrote: ------------------------------------------------------- > Is the RepStrap "Seedling" just a RepRap with a > McWire Cartbot instead of the Cartesian Robot 1.0? Pretty much. > If so, could I just build a v1.0 Seedling, make > the Cartbot 1.0 parts, and then switch the McWire > Cartbot for the standard Cartbot? Would I then > just have a RepRap? Yes, but tby JohnWasser - General
Larry_Pfeffer Wrote: ------------------------------------------------------- > Are the resins for this approach available, and > what's the ballpark cost/volume, anybody know? "In terms of consumables, the first thing to consider is the material. This is priced atby JohnWasser - General
RepRap SNAP Command Documentation Stepper Motor Controller SNAP Protocol Version 0 Extruder Controller SNAP Protocol Version 0 Looks like you will at least have to emulate the hardware to identify the type and version of each addressable device.by JohnWasser - Controllers
The Magnetic Rotary Encoder will allow the computer to know the position of the motor shaft. By tracking the position over time the computer can determine the speed. The computer can then increase the power (pulse width) or decrease the power to adjust the motor to the desired speed.by JohnWasser - Controllers
Larry_Pfeffer Wrote: ------------------------------------------------------- > Everybody: Please post, indicating whether you > can make that date. Saturday the 26th works well for me.by JohnWasser - Massachusetts, Boston RepRap User Group
Forrest Higgs Wrote: ------------------------------------------------------- > Since the polymerized monomer sticks to the glass > plate the is being raised, I guess I'm left to > wonder why it doesn't stick to that glass plate > that the polymerizing light is being shined > through? The diagrams says "Vacumm Diffuser Module separates each new layer bond from the glass after it'sby JohnWasser - General
It looks like USD$1395 is a very good price for a set of commercially RP'd parts. By comparison a FULL set of mechanicals (including cast versions of all the RP-able plastic parts, metal parts, and motors!) is GBPby JohnWasser - Reprappers
Looks like anyone can remove a pin. I clicked on the "Edit" button at the top of the name list, selected the "Timeout Restaurant and Sports" pin and in the pop-up information box on the map clicked on the "delete" link. I don't know if I'm SUPPOSED to be able to do that. Andromodon Wrote: ------------------------------------------------------- > As another question, how does one remove a "pby JohnWasser - General
A problem with using a string for the Z axis is that it provides no means of keeping the four threaded rods synchronized. If one axis slips, just a little, over time the stage will bind because the four corners are no longer in the same plane.by JohnWasser - Mechanics
Even if the ladder belt had a tenth of an inch of play that would translate to about 1/100 of a rotation on a 3" diameter cog. If the Z axis threads have a pitch of 1.25mm that would cause a vertical offset of 0.0125 mm. Since the specified positioning accuracy of the RepRap is 0.1 mm I think that will be plenty close enough. Squintz Wrote: -----------------------------------------------------by JohnWasser - Mechanics
And speaking of previously unknown Boston-area resources: The topic of electronics parts stores came up on the Make Magazine blog (http://blog.makezine.com/) and among the comments was a pointer to an electronics parts store in Littleton, MA called "Electronics Plus". Looks similar to "You Do It" in Needham: "Electronics Plus is conveniently located off Exit 31 on Interstate 495 in Littletoby JohnWasser - Massachusetts, Boston RepRap User Group
As near as I can tell the 'Enable" inputs on the stepper driver board 1.1 are not currently used by the Arduino electronics. It goes straight to the ENABLE input of the L297 so a look at the L297 specification would say what happens when ENABLE is pulled low. I think the easiest way to add a 4th axis would be to consolidate the limit switches with some OR gates, using only two inputs instead ofby JohnWasser - Controllers
If the LED side of the optical interrupter is infrared you might be able to tell if it is lighting up by pointing a webcam or inexpensive digital camera at it. They usually have some sensitivity in the infrared. Test the camera with a TV remote control to see if it is sensitive to IR.by JohnWasser - Controllers
It seems to me that one of the more complicated (and expensive) mechanical sections of the Darwin design is the Z-axis drive. The toothed drive belt is not cheap and the matching cogs have too fine a pitch to be printed with a RepRap. I've read of someone experimenting with bead chain. If the cogs are printable on a RepRap and a way is found to create continuous loops then that would be a fairby JohnWasser - Mechanics