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Everybody here is a developer. Share what you are doing !
Re: Electrical noise in temperature measurement? - 13 years ago
It would seem that the issue definitely stems from the mill power supply. With the scope probe grounded, I saw 50mV+ of noise when turning on the supply. Might be some of the problemby Koko76 - General
Electrical noise in temperature measurement? - 13 years ago
I am working on and extruder for use at first with an existing CNC mill. I will be using the mills 4th axis to drive the extruder stepper, so I am using the mills 4 axis drive electronics. Since I'm not using the standard electronics, I've taken pieces from the existing electrical boards and put them together to make a temperature controller. I have an AD595C with a K Thermocouple. Output of tby Koko76 - General
Re: 2nd layer not printing on first - 13 years ago
To test if you are missing steps write some g code of your own to test the motion of the system only. Try moving in a square, again and again. Attach a sharpie and write on paper, You will see if things are off. Missed steps "look" like what you are describing, and have many many causes. Biggest one would be mechanical interference, check all axis for smooth motion with belts disconnectedby Koko76 - General
Re: Where can I get recommendations for designing parts (thickness, etc) - 13 years ago
What is it that you mean by "correct"? Is the question : Can this part be fabricated using a given method (in this case printing on a RepRap or similar)? Are the dimensions of the part suitable for a given load? Does it look right? Are the dimensions given correct for the part to fit? You are making a part for a machine that no one has built before (assuming your version is unique) so it's goingby Koko76 - General
Re: Vapour Smoothing System (HP) - 13 years ago
It's a cool idea, but personally I'd be wary about vaporizing solvents. Lot's of opportunity for danger when you do things like that. They use the words "carefully controlled conditions" but don't say how carefully controlled.by Koko76 - General
Re: Mantis 9.1 - 13 years ago
Traumflug Wrote: ------------------------------------------------------- > Watching this thread for a while, I think I want > to chime in here. Using a full fledged PC also has > the cost to require a lot of energy, e.g. for hard > disks, monitor, you name it. Also there isn't much > a PC can do for a Mendel-type machine an Arduino > can't. > > Insisting on G02/G03 curvedby Koko76 - General
Re: Mantis 9.1 - 13 years ago
Although you might use a separate controller to actually generate pulses (I use a board with an fpga for this) you still need trajectory planning. Both EMC and Mach3 do this and keep tool speed constant. This becomes important when trying to get cutting tools to work right. They also have several levels of hardware interrupt for various things like limit switches, spindle control, coolant oby Koko76 - General
Re: For developing new forms of printers. - 13 years ago
I'm somewhat familiar with hobby servos, I've used them before in many projects, including bipedal walking robots. To begin with positional accuracy of those units is not going to cut it for motion control of the sort needed to make a printer. Stock servos do not give positional feedback, and using the potentiometer to do so is going to leave much to be desired. A potentiometer is NOT an encodby Koko76 - General
Re: For developing new forms of printers. - 13 years ago
Motion control really isn't the bleeding edge, industrial positioning systems have been at work for many years. Easy and relatively cheap access to them is newish, but again, nothing really groundbreaking. Servo control systems are rarely cheaper than steppers, especially accurate servo control. "Real time" position feedback is not a trivial thing, and complications arise when the mechanicalby Koko76 - General
Re: Mantis 9.1 - 13 years ago
You aren't going to "upgrade" a PC parallel port system like EMC2 or Mach3 by using RepRap electronics. For useful milling you need far more in terms of motion control, acceleration, and trajectory planning. G02 and G03 would be a good start. Without the capability to mill arcs using interpolated movement rather than sequences of tiny lines, you really limit what you can do for making good parby Koko76 - General
Re: Architecture Models? - 13 years ago
> > You can also do a powder printed mendel, and then > paint the parts with an epoxy. (I'm not sure how > well that works.) > > I have seen a skateboard ~16" long deck made from epoxy saturated powder print that had a 180 pound guy ride it, and not delicately either. Powder printing with the right infiltration can be incredibly strong. Even the CA infiltrated ones are verby Koko76 - General
Re: Glass nozzles for extruders - 13 years ago
Marble molds are usually made of graphite (mine are). The problem with shoving the glass in is that the wall thickness in the smooshed region will be dependent on the amount of glass that is hot enough to move, and this is difficult to judge and control. Drawing the point out and cutting it off, then grinding back as has been done is going to be the best way to get a smooth tapering bore to a tby Koko76 - General
Re: knurling knowledge kneeded - 13 years ago
I'll put up a pic in a bit, you can see my work so far at teamnar.blogspot.com . I'm doing a different setup than most, timing pulley reduction with the large pulley bored out to take a 5/8 diameter brass rod. I bored the center of that to take a couple needle roller bearings. Whole thing spins on a shoulder bolt across the frame of the extruder. I dislike live shafts except where absolutely neeby Koko76 - General
Re: knurling knowledge kneeded - 13 years ago
How about a $6-8 single tap that's exactly what you need? I don't advocate buying any kind of set, just the ones that you need at the time. Then you will always have the good tool, and if you do find a project you need it for the good one is waiting for you. The average cordless drill sold at Home Depot or Lowes has an engineered lifetime of 12-13 hours of drilling time. People buy disposableby Koko76 - General
Re: knurling knowledge kneeded - 13 years ago
Oh boy where to start...disclaimer I guess, I am a machinist by day so forgive some of the overly #$@ retentive tendencies in this. Number one you aren't knurling, as knurling is a different process. Similar result but totally different. Most common knurls use pressure to form metal, cut knurls are big $$$. You wouldn't want a knurling tool for this job regardless of type. Now on to the taps.by Koko76 - General
Re: I MUST build a new extruder advice please. - 13 years ago
Anthong Redbeard Wrote: ------------------------------------------------------- > Quick update, I think I came up with a very simple > / cheap solution to sensing a common failure to > take action... > > on my new extruder I'm putting a thermistor as > high on the brass tube as I can, then will trigger > a series of actions of the temp of the top > thermistor is with a dby Koko76 - General
Re: New Makerbot Thing-o-matic model - 13 years ago
Anthong Redbeard Wrote: ------------------------------------------------------- > I like the direction it's heading but I wouldn't > want to replace a heated bed with a conveyor, from > what I can tell the conveyor belt doesn't have a > heated bed. > > The rest of the improvements sound great. I'm > curious to know the objective print quality > between it and a Mendel. Iby Koko76 - General
Re: General Reprap Design Idea - cartridges - 13 years ago
My build is not anything like a RepRap, but I am using a similar cartridge idea to mount the actual "head" of the machine, for several reasons. One is to make switching to a totally different head type easily, if not automatically possible. And two, to make it easy to swap in spares. A side benefit is the way that the mount is designed, it makes the head able to "crash" without damage. Lotsby Koko76 - General
Re: Question about resolution - 13 years ago
Autarkyboy Wrote: ------------------------------------------------------- > What about commercial 3d printers like Stratasys? > Do they have the resolution to print this? > > What about a 5 axis mini milling machine? Like > this , it cost > 1225 $. Has anyone any experience with milling? The five axis mill is only part of the puzzle. Even if the listed machine was 5 axis (itby Koko76 - General
Re: How do you post process (clean up) your parts? - 13 years ago
An injection molding machine is next to useless without molds, which are hard to make without a subtractive cnc and or edm machine. Even in a cnc mill detail isn't free, the smaller the stepover (closer together each successive pass is) the longer it takes to cut the part. Then you need to consider what kind of tool you can get in where you want to cut, and how. A .0625" ball end mill for examby Koko76 - General
Re: Glass nozzles for extruders - 13 years ago
Wacky idea for those with a drill press. Take a small block of aluminum drill a hole through it as close as you can to the size of the tubing. Make the hole relatively close to the edge of the block. Saw through the side of the hole, making the slot parallel to the axis of the hole. Then drill through the slot, perpendicular to the slot, with a tap drill. Open one side with a clear drill.by Koko76 - General
Re: Glass nozzles for extruders - 13 years ago
You just hadn't mentioned safety gear before, I feel it's important that others not familiar with this stuff know the right precautions to take if they decide to try it for themselves. Don't mean to come off as a safety Nazi. I have the torch, kiln, and a good stock of boro, as well as a couple lathes/spindles that I could press into some use. Not set up at the moment as it's been too hot to hby Koko76 - General
Re: soft grip filament drive for extruders? - 13 years ago
I am going to attempt to use a brass hobbed drive roller, with a urethane idler roller on an adjustable but not sprung axle. We shall see if its effective.by Koko76 - General
Re: Can Mendel handle my huge Iron Man suit project???? 
- 13 years ago
first, most laser cutters can't cut metal - just engrave it. That specifically depends on the laser in question. We have a 2500 watt and a 4000 watt laser at work. The 4k will cut 3/4" steel at 30 inches a minute. Thin aluminum is at more like 300-400 ipm. Many sheet metal shops use laser blanking, its even competing favorably with punching with some more modern systems than we have. Theyby Koko76 - General
Re: Glass nozzles for extruders - 13 years ago
Couple of notes on your glass nozzle project. First off a word of caution, flame working borosilicate tubing can be very dangerous, particularly to the one thing that's hard to replace, your eyeballs. The sodium flare given off by working boro is enough to damage your eyes without protection. Get yourself some filtered glasses. Clear boro isnt quite as bad as colored, so you can use the cheapeby Koko76 - General
Re: New person here! (and a few questions) - 13 years ago
The point was not the cost or what to do when the inevitable happens, take any component down to a $0.03 washer. If all you plan for is the bare minimum, as the original poster seems to be doing, prepare for problems in the end. Everyone has a cost/time whatever threshold, I'm not criticizing people for being "cheap". It's just that starting a project with a lower than average budget an zero rby Koko76 - General
Re: New person here! (and a few questions) - 13 years ago
Disclaimer : my 3d printer is currently in the design and construction stage. That being said, I have build a rather robust 4 axis milling machine with stepper drives, as well as a host of other projects in my day. I don't want to come off as negative but going at it in the absolute minimum figures with everything is not the path to success. What happens when you accidentally toast one of yourby Koko76 - General