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Printing issues ...
Re: A few newbie (pre-purchase) questions - 13 years ago
There seems to be some variability in the smell of extruded ABS. I've only ever had a slight odor from ABS, and my wife has never even mentioned it, much less complain. I do know what ABS can smell like, based on experiments involving a soldering iron when I was young. That stank enough to give me a headache. I probably should have stopped... So far, I've used ABS from MakerGear and Protoparadigby Dale Dunn - General
Re: Mendel wobble in z-axis of prints - 13 years ago
Karl_Williams Wrote: ------------------------------------------------------- > After a few months of getting very nice prints, my > mendel has developed the same problem. Will > replacing the captive nuts solve this problem? It > seems that the nuts are over constrained in the > mendel design. Is there a way to let the z-axis > nuts move slightly in the holder since it is the &gby Dale Dunn - General
Re: Convert RepRap files to STP - 14 years ago
A free method to do this is described in the second half of this post. If you get too many manifold errors, you may not be able to make a good STEP file. If your vendor hasn't been able to get volume information (sounds like a manfold problem) it may simply be that you need to repair the .stl file before sending it to them. There is a free on-line tool for repairing slt files, but I haven't usedby Dale Dunn - 3D Design tools
Re: z axis treaded bar rotating but not traveling - 14 years ago
Something is coming apart, if the screws are turning and it won't go up. My guess is X assembly jammed on the Z rods, and the Z screws are being pulled out of the coupler. Can you tell if this is happening?by Dale Dunn - General Mendel Topics
Re: drooling prints - 14 years ago
I think I see some layer height and width issues. The real experts may need to know what hot end, nozzle diameter, layer thickness, width, nozzle temperature, material and what process you used to calibrate. For the record, that is far, far better than my early prints.by Dale Dunn - Mechanics
Re: Some thoughts on a cheap, fast and accurate SCARA reprap - 14 years ago
Interesting idea for support. Have you read Gary Hodgson's thoughts? The SCARA robot is going to be a challenge. You will need very high angular positioning quality to achieve prints comparable to the Cartesian bots. The second challenge will be using a printed screw for Z axis. Since Z position and layer thinckness are critical to print quality, you might want to start with commercial screws foby Dale Dunn - Developers
Re: Anyone Heard of Proto Paradigm? - 14 years ago
I recently started using some 1.75 natural ABS from them. It seems to be working well so far.by Dale Dunn - General
Re: Plastruder-ish filament driver - 14 years ago
The MakerGear drive is a gear from SDP/SI. I don't have the part number handy, but it has been posted in the MakerGear Google group a couple times.by Dale Dunn - General
Re: Marlin: Mostly awesome ... - 14 years ago
I think I had similar issues, but it was a year ago and I've forgotten the specifics. It may be that you're tripping the thermal shutoff on the stepper drivers. Try a long manual Z move and see if it pauses intermittently on the way, stopping short. Some firmwares shut off the Z steppers between moves by default to keep them cooler. Others don't. I think most of them have a setting, and "late enby Dale Dunn - General
Re: Temperature vs. Print Quality (ABS) - 14 years ago
210° is what I've been been using for ABS with my MakerGear hot end. Sometimes 200°, sometimes 220°. The temperature read by thre thermistor with vary some from one machine to the next, depending on exactly where the thermistor is, how good the thremal contact is, etc. On top of that, different batches of ABS will require different extrusion temperatures. So, for every batch of ABS on your machinby Dale Dunn - General
Re: SCAD - 14 years ago
Pasta, this comes up from time to time as people who are familiar with more powerful tools get exposed to RepRap. I agree with you. It's not difficult at all to grasp how to use OpenSCAD. Hopefully FreeCAD will mature (I hear you can script it too, if you like) soon and free us from SCAD. In the mean time, you'll never convince people to stop using their favorite tools, just like no one could poby Dale Dunn - General
Re: Whats with the "ribbing" on my prints - 14 years ago
Dale Dunn Wrote: ------------------------------------------------------- ........ > Since installing the isolators, I haven't printed > any parts that don't have sections so thin they > end up being filled 100% despite Fill being set to > 35%. I was thinking that perhaps the bulges are a > symptom of a slight overfill condition resulting > in a periodic overflow. I need to try aby Dale Dunn - General
Re: Globoidal CAM in OpenSCAD - 14 years ago
What you are describing would be called a sweep in SolidWorks, and maybe other systems. However, if you are planning to do this with a 2d profile, it won't work. Modeling cams is a subject that turns up from time to time in CAD forums because sweeping the 2d profile will not result in the same shape the end mill or your cam follower will follow. What you need to do is create a multitude of copiby Dale Dunn - 3D Design tools
Re: Whats with the "ribbing" on my prints - 14 years ago
jcabrer Wrote: ------------------------------------------------------- > This is clearly Z-Axis wobble. Post a picture of > your vertical threaded rod, including the bit > where stepper meets rod, and I can tell you where > the problem is. I'm not so sure. I had some Z axis wobble that clearly measured the same pitch as my Z rod. The pattern in the parts noticeably followed a helicaby Dale Dunn - General
Re: Use inches instead of metric system - 14 years ago
It would be easier to get used to working with mm. Try to stop converting to inches in your head. Machining feed rates aren't really a relevant comparison to printing feed rates anyway. I was raised on inches, but working in the world economy, I've had to start thinking about machining in mm (I design fixtures for a living). It doesn't take too long for the metric numbers to start feeling comforby Dale Dunn - Slic3r
Re: GT2 Belts and Pulleys teeth count? - 14 years ago
That sounds about right, the shaft vs bore thing. The 12-tooth GT2 pulley is actually what I use, and it does the job admirably. I wouldn't want to make the center bore without proper tools though (lathe, etc.).by Dale Dunn - Mechanics
Re: GT2 Belts and Pulleys teeth count? - 14 years ago
I don't know why it would say 12 is the minimum, unless that was the smallest pulley the author could find at the time. That's what I'm finding after a quick search at SDP-SI. The same place shows the 10-tooth stock. They're not going to sell pulley stock with a tighter radius than the belt can bend, so I'd go with the 10 and get a little more force and precision.by Dale Dunn - Mechanics
Re: [project] Heavy mendel, a self replicating 3Dprinter/mill/PCB engraver - 14 years ago
Nice. How repeatable do you expect the wire drive system to be?by Dale Dunn - General New Machines Topics
Re: Filament and rising costs - 14 years ago
ProtoParadigm has 1kg [2.2lb] of ABS starting around $40.by Dale Dunn - General
Re: help brainstorm a better bed leveling adjustment mechanisim - 14 years ago
Well, that might work. Or maybe drill tap half of a coupler, if there is enough wall thickness. To keep the bed low, one could redesign the Y carriage with lower mounting points.by Dale Dunn - General Mendel Topics
Re: durability & strength of parts printed - 14 years ago
Be aware that ABS or PLA printed gears won't have the wear resistance of Nylon or Delrin gears, especially if they were cast with something like a glass fill. Printed gears can be strong enough, but they will wear out much faster. Especially if you don't reproduce the tooth forms accurately.by Dale Dunn - General
Re: Solid Model files for Prusa Mendel - 14 years ago
The STEP directory in my repository for my fork of the Prusa has STEP models converted from .stl files I took just after Prusa 2 was announced. If you want more current models, and can import STEP files, then you can use FreeCAD as an intermediary to make STEP from current stl files.by Dale Dunn - General
Re: [project]Self replicable 3Dprinter/mill/PCB engraver - 14 years ago
I'll be watching for this. Your design goals are similar to something I'm collecting ideas for. I'm curious how the steel cables will work. Will they wind onto a drum?by Dale Dunn - General New Machines Topics
Re: save all your scrap plastic - 14 years ago
My day job is designing fixtures for machining die cast aluminum. Die cast aluminum accuracy can be comparable to or better than FFF plastic, especially when compared to the simple bracketry used to build RepRaps). Warping is a lot less than I've seen come off my printer in ABS, but that may have to do with careful cast part design. Some parts do go through thermal stress relief, but that's onlyby Dale Dunn - General
Re: Parametric pulley - lots of tooth profiles - 14 years ago
I think the reproduction aspect of RepRap is in a difficult place with pulleys. We want to print them, but the tooth profiles that suit the diameter pulleys we want to use are too fine for easy FFF. I've been very happy with my GT2 pulleys from Stock Drive Products, but I don't see ever printing them. I wonder if even powder bed or laser sintering can produce a pulley that fits a GT2 belt reallyby Dale Dunn - Developers
Re: help brainstorm a better bed leveling adjustment mechanisim - 14 years ago
richrap Wrote: ------------------------------------------------------- > I think that's a similar idea to what Nophead has > implemented on Mendel90 - Using simple threaded > metal spacers and nuts to screw and lock - no > springs. That standoff construction is what suggested to me the idea to turn the differential pitch screw idea into two screws of different pitch connected by a cby Dale Dunn - General Mendel Topics
Re: Marlin Arc Detection - 14 years ago
TheIrrationalDevotion Wrote: ------------------------------------------------------- > @DaleDunn > > I use SW to do all of my modeling as well, but > haven't had the chance to look. Does it have the > same functionality as openscad's > "$fa = 5, $fs = 0.5" > > Also, if I'm following correctly; Increasing the # > of facets will lower the # of arc-artifacts? or is >by Dale Dunn - Firmware - experimental, borrowed, and future
Re: Marlin Arc Detection - 14 years ago
nophead Wrote: ------------------------------------------------------- > Seems poor for a professional package as it makes > it useless for any 3D printing or milling, which > needs even smaller facets as there is no smoothing > effect. Perhaps this is why profesional CAM software works directly with the BREP instead of using a faceted intermediary representation. I've never even heaby Dale Dunn - Firmware - experimental, borrowed, and future
Re: Marlin Arc Detection - 14 years ago
I have access to SolidWorks, and it has similar controls. The problem is most apparent to me when I print a large radius. I did some parts a few months ago that were long enough to reach corner to corner on my Prusa, with arcs on the long sides of about a 400mm radius. With the highest accuracy settings SolidWorks allowed, the facets were still visible.by Dale Dunn - Firmware - experimental, borrowed, and future