Don't get me wrong I'm all for 'building it yourself'. My entire machine is a mendel design without one printed part, except for two gears on the extruder. But for all you folks who say its easy to build a nozzle with .3 to .4 mm hole please give it a try. Your challenge is to take the smallest pin drill avaliable, drill thru 1mm of brass (assuming you can get to that distance via the blindby dean448 - General
Moving from theory to how to build a hot end is a bit off topic, and I'm sure the opinions vary widely. Like I said above, why bother building something that won't turn out to be as good as something you can buy? I purchased the nozzle, liner and stainless down tube from Makerbot. I fabricated the heater block, but you can buy that too. I'm sure they purchased these parts from someoneby dean448 - General
Agree. Maintain the same minimal clearance between the PTFE liner and filiment from the top of the cold section to the inside of the nozzle tip. Minimal means it sides thru without drag but isn't loose. Keep in mind that under pressure and heat the actual clearance is the result of how much the tube is allowed to expand into the stainless liner. Everything should mate up with out being loby dean448 - General
I have no experiance using this design but would stay away from any hot end design that uses a joint between brass and PTFE to hold it all togather. Because PTFE softens due to the heat, you are always on the edge of pulling the threads out. Also the purpose of that long section between the actual hot end and the extruder body is to insulate hot temperatures from reaching the extruder body.by dean448 - Reprappers
I use a totally enclosed PTFE tube that goes from the top of the cold end to the inside of the nozzle tip. Totally enclosed meaning that it can't move up, down or out. I tried other concpets like transitioning from PTFE to brass with no luck. The material wants to flow back behind the tube through the joint. The hot material is at a high pressure. It doen't want to go out that small holeby dean448 - General
I've seen posts where people complain about printed couplers failing. Does this idea get around having to use a printed coupling? or do you feel the sprial helps out somehow? its a cool look and could help with any slight missalignment between the screw the stepperby dean448 - General
You might also consider how often and the amount of adjustment required. If you adjust it once and the correction is small you could even use shim stock. In this case a shim could be a piece of paper. Think KISSby dean448 - General Mendel Topics
If you are looking for a solution you need to fully describe the design of your hot end, probably the whole extruder. No one would be able to tell that 1/2mm clearance causes jamming.by dean448 - Printing
I keep reading these threads were folks are looking for ready to run printers. The response from the folks who have working printers is always to go a similar route to the way they went. I've come to the conculsion that some folks may not be able to get there due to the difficulty of hardware, firmware and software. They then buy a unit from some internet providor, get no support and eby dean448 - General
Yes you need to tune the image to the printer. I sliced the file using Skeinforge with a layer thickness of .33mm and the fourth layer is per the attached. The print was identical. So in order to see if your file is printable, all you really have to do is slice the STL file. Keep in mind that nozzles do very so .33 is not universal, and the finer the nozzle the better the resolution butby dean448 - General
First off any concept that make you think about the mechanics, physics, firmware, ect like this is a good one and I think this concept is great. I'll join the rest who think the key challenge is in the control of the steppers. Steppers aren't torque control but position control, sort of. Isn't the trick to control belt tension when moving the X axis? Tension would represent the torqueby dean448 - Mechanics
it might be worth looking at the hobbed bolt for any buildup after things go bad. Look for buildup in the grooves. I had an intersting exchange somewhere on this forum where someone recommended using an M4 tap instead of an M3 The problem with an M3 is that the grooves are shallower and tend to build up. I've been using an M3 for a long time with success but I'm putting considerable force oby dean448 - Printing
I use a PTFE coated nozzel which allow you to clean any material off easily. When the extruder is operating properly there is no real benifit from the coating. So I'd say that polishing won't help but nothing prevents you from giving it a try. When your extruder is operating properly material flows freely from it and it doesn't have a tendency to curl back. Since my mendel has a singleby dean448 - Printing
John Oly, I finally got a chance to take a look at about three videos posted on partdaddy.com the other day. Is that your goup or someone else? They were shots of a printer working on a raft. The unit had a triple gear extruder all in plastic. What I couldn't help notice in the video was the pausing. When looking at streaming video you never know if pausing is from the video or not. Iby dean448 - Mach3
Mach3 will run up to 500 lines without a liscense. My Mach3 files for wood cutting are between a few hundred and a couple thousand lines. My printer files are often above 75K lines. Keep in mind that a printer is all straight cuts because the mesh is all triangles. Depending on you CAM processor Mach3 relys on arc cuts which cuts the code down considerably. Using G03/G02 cuts very smooby dean448 - Mach3
I had a reason to install mach3 into an obsolete PC a week ago. The computer was running XP and had a parallel port as built into the main board. No matter what I did I couldn't tune the output from at PC. The steppers moved, but not with a nice constant hum like my other machine. I dialed them back to 1/2 of the max speed and was able to demo something, but I wouldn't want to cut that wby dean448 - Mach3
I uploaded the pulley to the Autodesk 123D gallery Timing belt pulleyby dean448 - General Mendel Topics
It can not print without some sort of support. Defining support is not that easy. Support can be a previous layer parallel to the print direction, even at some angle (>45 might work). Or support could be walls that are not parallel to the print direction (Spanning across two fixed walls). I've observed that when printing across larger spans the material tends to sag initially then pby dean448 - Printing
Interesting comment about dropping code. I had that problem when using Gen3 electronics. It was just not keeping up. Switched over to ramps and have no issues keeping up, but I'm not trying to drive the printer at high speeds. All modeling software outputs STL in a series of triangles that look like flats on any curved surfaces. One issue I had with Sketchup is that the flats are more prby dean448 - General Mendel Topics
When I open your sketchup models all the holes are a series of flats. the larger the hole the more flats. Is this part of the design or sketchup? I got frustrated by sketchup some time ago and went to another free modeler called autodesk 123D. The few parts I looked at look pretty good. They are all printable. The only concern I would have is strength of some features in these prby dean448 - General Mendel Topics
I'm not sure if this post belongs here or in the Skeinforge folder... This is an FYI on folks trying to decide which way to go. For new folks... both programs allow you to connect up to your printer, allow you to run controls and ultimately send gcode to the printer. I recently had to move from my trusted XP machine to a Win7 64 bit machine. I decided to give pronterface a try and foundby dean448 - RepSnapper
I'll keep an eye out for the photos. The design looks clean. I have a threaded rod mendel and find no issues with rigidity. I have seen plenty of posts where folks complained about lack of rigidity so I know it exists. I believe that the weakness with the threaded rod mendels isn't the rod but the printed corner members, mostly based on a guess because I'm using corners that were builtby dean448 - General Mendel Topics
Sounds good. You put a lot of thought into this. I'll take your word on holding and alighing the upper Z axis guide rods. I'm not getting whats going on by the photos alone.. but no need to at this time. On the less technical side.... I believe that in order for any of these designs to become popular they need to target one of the following user types: 1) I need a printer fast, don't whatby dean448 - General Mendel Topics
Your design appears simple and rigid. I like the feature were you can align stuff in along the length of the extrusions. printed parts seems minimal. Design is expandable (can scale it up) Possible Issues: from looking at your photos I would be concerned about Y axis alignment in the Z direction... possibly corrected by adjusing the corner joints? Also the alignment of the upper Z axisby dean448 - General Mendel Topics
I just happened on the cnczone forum covering 3D printers and found cnc2printer3d who is doing something similar to you. Its interesting that this website is concentrating on a seperate temperature controller, which makes sense because most folks using Mach3 don't have a temp controller. I can't say how common this is but I only turn the temperature on at the start of the job and turn it offby dean448 - Mach3
OK. I wonder how many folks have a parallel port on the back of their computer? A smoothstepper card adds another $160... the last time I checked. By the way for anyone not following this a parallel port was a used for many years to drive printers. This obsolete port has about 25 wires and ALL are used by Mach3 to control the electronics on your machine becase its sending step and directioby dean448 - Mach3
Welcome John oly I'm seeing a different and intersting point of view in your website... I'm sure sure you will get many comments. Since you asked to add a Mach3 topic it would be interesting to start with the advantages of using Mach3 to control a 3D printer. I'm not doubting that it can be done but why would someone getting into this want to pay for Mach3 when they can get open source cby dean448 - Mach3
Early on I followed this path. Host software with gen 3 electronics. 20mm cube barely looked like a cube if it would print at all. Errors all the time when trying to communicate between the PC and Gen 3, extruder jammed a lot... tried to manualy write gcode to debug... I discovered the following: Host software is poorly written and won't reliabiliy work with gen 3 - adopted newer code Gen 3by dean448 - Reprappers
When running PLA without a heated bed I'm seeing warping start at a length to width ratio of over 5:1. I normally run the length parallel to the X axis and have problems keeping the ends of the long axis on the table. Sometimes I notice the first dozen or so layers are warped then they become straight, resulting in a non flat bottom only. I'm printing on double sided carpet tape to help to hby dean448 - General
Tubes and hose clamps might be OK to get started. After that try to design and print one.by dean448 - Mechanics