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People building or using RepRaps.
Re: many motors off one ramps board 
- 10 years ago
How many independent axes are there? A lot of Prusa printers run 5 motors on 4 stepper controllers. (1X, 1Y, 2Z, 1E). Power you'll have to figure out based on size and number of motors and anticipated loads.by Dale Dunn - Developers
Re: BOLTS, a standard parts library for OpenSCAD and FreeCAD - 10 years ago
You seem to excel at giving me tasks that require me to fill in the vast holes in my GitHub skill set. Most likely, I probably still have not achieved competence. The test with mm units was successful. I have some more work to do to be able to test something with inch units. Specifically, using the key in a configuration name is a problem. The forward slash in the fractional inch thread sizes isby Dale Dunn - 3D Design tools
Re: BOLTS, a standard parts library for OpenSCAD and FreeCAD - 10 years ago
OK. I won't be able to test until tomorrow evening.by Dale Dunn - 3D Design tools
Re: BOLTS, a standard parts library for OpenSCAD and FreeCAD - 10 years ago
Oh, it's downstream from my fork. I totally missed that. I will need to pull your experiments from there? For example, I'm not sure if the units in design tables code is in your master branch or solidworks branch. Thanks for the link. I've found that book a few times while searching for answers. I was so focussed on finding answers that I didn't notice what it is. I need to take the time to reaby Dale Dunn - 3D Design tools
Re: BOLTS, a standard parts library for OpenSCAD and FreeCAD - 10 years ago
Quotejreinhardt Ok, that is nice. It seems that is well doable. I have now a branch where I will keep track of your work and add experimental stuff: I just added some code that adds the units to the design table. I hope that works, as I write strings to the spreadsheet instead of numbers. Can you test that? I almost missed this post. Yes I can test that. It should work, since I've done theby Dale Dunn - 3D Design tools
Re: Layer Striping - 10 years ago
It's difficult to see if that's Z axis wobble or a Z layer height that's not an integer multiple of the Z full step height. The wobble comes from having the screws constrained rigidly enough to influence the carriage despite the smooth rods (or whatever your ways are). The full step height issue comes from the repeatability of fractional steps being different from that of full steps. If your laby Dale Dunn - Printing
Re: BOLTS, a standard parts library for OpenSCAD and FreeCAD - 10 years ago
I'll try to get that done this week. I'm building a quite a to-do list.by Dale Dunn - 3D Design tools
Re: BOLTS, a standard parts library for OpenSCAD and FreeCAD - 10 years ago
Quotejreinhardt Can newer version save in old file formats? Something like "Save as" -> SW2010? Targeting only one version requires a difficult tradeoff: * BOLTS is usable for everyone with the targeted version or newer, so to maximise audience one should target a maximally old version * Contributors need to have the targeted version or older, so to maximise contribution one should a maximalby Dale Dunn - 3D Design tools
Re: BOLTS, a standard parts library for OpenSCAD and FreeCAD - 10 years ago
Quotejreinhardt... Good point. That requires some thought. BOLTS knows about the units of the parameters in the blt files, but currently does not use this when exporting to a design table. Currently BOLTS assumes that a parameter is a length given in mm, unless stated otherwise (like e.g. ). It should be not a problem to add other units if needed. Can Solidworks read units from designtables? Aby Dale Dunn - 3D Design tools
Re: SolidWorks i3 - 10 years ago
QuoteNormandC QuoteDale Dunn Ob-pedantry: I understand the default view orientations are common in the car designing biz. Notice I said "default". The standard views could rearranged to anything you like, inclusing some loony diagonal arrangement. I have no idea of the meaning of that neologism (it's not an existing word) or if it was directed toward me, nor do I care. In my own experience a greby Dale Dunn - Reprappers
Re: BOLTS, a standard parts library for OpenSCAD and FreeCAD - 10 years ago
SolidWorks version compatibility: You have correctly guessed the process for moving a SolidWorks file to a newer version: just open and save using the new version. With the small files in a BOLTS distribution, the update process will be effectively transparent when the file is opened to add the design table. Because the update is so easy, I don't think it will be worthwhile to maintain separateby Dale Dunn - 3D Design tools
Re: BOLTS, a standard parts library for OpenSCAD and FreeCAD - 10 years ago
Unless we append units to every number the params put in a design table, we will need separate model files for inch and metric hardware. Perhaps convert units on export to standardize on mm in the design tables? I would prefer separate model files for different units. Do parameters need to be a data type that includes units? It's not inconceivable that some standard specifies cm or m for somethiby Dale Dunn - 3D Design tools
Re: BOLTS, a standard parts library for OpenSCAD and FreeCAD - 10 years ago
I'm experimenting with metadata, and I need to be able to add more than the key and columns. I need to be able to add description and standard as metadata.by Dale Dunn - 3D Design tools
Re: BOLTS, a standard parts library for OpenSCAD and FreeCAD - 10 years ago
How should backwards compatibility be dealt with? With few exceptions, SolidWorks files are not compatible with older versions of the software. It's not at all unusual for users to be using older versions. I have a customer who requires SolidWorks 2011 files, when I'd rather be working with SolidWorks 2014. So, I work in 2011. That's what I'm using for BOLTS at the moment, being aware of the backby Dale Dunn - 3D Design tools
Re: BOLTS, a standard parts library for OpenSCAD and FreeCAD - 10 years ago
Got it. I needed to add python to my path so I could run it from the BOLTS directory. I failed to glean that from the "How to use a development checkout" page.by Dale Dunn - 3D Design tools
Re: BOLTS, a standard parts library for OpenSCAD and FreeCAD - 10 years ago
OK, I've worked through the GitHub processes to fork, clone, edit and sync to my repository. I added files for nuts to my repository here. It should be visible as a fork of BOLTS as well. Please feel free to open issues for items you need from me to proceed. I also did this: c:\Python27>python C:\0Home\GitHub\BOLTS\bolts.py export solidworks Traceback (most recent call last): File "C:\0Homby Dale Dunn - 3D Design tools
Re: SolidWorks i3 - 10 years ago
QuoteNormandC That last link has the printer assembly rotated on its back (with Y axis as "up") which most probably means it was modeled in SolidWorks, because it's the only CAD system I know of that stupidly puts XZ plane as ground instead of the universally acknowledged XY plane as ground. So maybe you can ask Thingiverse user twelvepro if he's willing to share his original files. Ob-pedantryby Dale Dunn - Reprappers
Re: BOLTS, a standard parts library for OpenSCAD and FreeCAD - 10 years ago
I figured a SolidWorks user's supplement would eventually become necessary. I should be able to make some contribution there, but I'll wait until I have some idea what I'm talking about.by Dale Dunn - 3D Design tools
Re: BOLTS, a standard parts library for OpenSCAD and FreeCAD - 10 years ago
Thanks, I think that will help immensely. I got as far as figuring out that BOLTS is a command-line tool, and even did "./bolts.py --help" to convince myself that I had the install correct. I'm on Win7, I can't write Python (though I might be able to read it slightly), and I barely know Git. I think I understand fork, commit, pull, pull request, and the reporting of issues. So I was well satisfiby Dale Dunn - 3D Design tools
Re: CoreXY Build - 10 years ago
Nice! The belts in the t-slots looks nice and tidy. Please don't use screws for the Z axis though. The threaded rods aren't perfectly straight and cause the dreaded Z-wobble. Have a look at using cables of belts for the Z axis. Tantillus has excellent layer alignment with the cable Z axis, and Ingentis has a large belt-driven Z axis working.by Dale Dunn - Reprappers
Re: BOLTS, a standard parts library for OpenSCAD and FreeCAD - 10 years ago
I thought I answered this this morning. Maybe I forgot to press "post". Here I Go again: Last weekend I downloaded a clone and got to work trying to understand everything. I have nut.sldprt and .base files, but I didn't get as far as getting BOLTS to generate output based on them. I have Python and the relevant dependencies installed, I just ran out of time learning how to actually get BOLTS toby Dale Dunn - 3D Design tools
Re: Rapid Tool-Head changer (very light multi-extruder) - 10 years ago
MattMoses, I like this idea of a single stack of magnets. The force of the magnetic coupling could be largely negated by parking the tool over or under a stack of opposite polarity magnets mounted in the magazine. The only problem is, the magnets are where I want the tool body (extruder, digitizing probe, engraving spindle, etc.) To be.by Dale Dunn - Developers
Re: 3D Infill Algorithms, Experimenting - 10 years ago
How did you choose OpenSCAD instead of OpenCASCADE in FreeCAD? I would think it would be more robust, but I don't really have even an inkling of the programming behind such a project as this. For my other ideas on infill, see my comments on Gary Hodgson's blog post here.by Dale Dunn - Experimental
Re: Z wobble hack - printed part - 10 years ago
I designed a similar mod for my MG Prusa, but on the nut that does the lifting. It helped immensely. My layer alignment errors are now dominated by the wobbly Mendel frame. Parts for an Ingentis derivative are now accumulating...by Dale Dunn - Tantillus
Re: Prints are too small? - 10 years ago
ABS shrinks when it cools, which is also the cause of warping. Print a test part and figure out how much your filament shrinks in your machine. Find the scale setting in your favorite slicer and use it to compensate. Hopefully it is saved with the material profile so it gets applied automatically. I keep forgetting to look into this because it's been so long since I printed something that had toby Dale Dunn - Printing
Re: geard stepper z axis - 10 years ago
Well, you could print the gears, like Tim Rastall (jimjimma here) did for his Ingentis printer's Z. Find it on G+, or about halfway through this thread. Scroll down until you find the geared version. Several other ideas are discussed in that thread as well.by Dale Dunn - Mechanics
Re: Use pulley as idler - 10 years ago
I've had good results using the toothed side of the belt against the idler. If the idler has flanges to keep the belt from running off, the teeth will rub on the flanges and cause noise and maybe wear and artifacts. I printed a crowned pulley to keep the belt on it without the problems caused by flanges. Crowned pulley: Thingiverse 14117by Dale Dunn - Mechanics
Re: New polar concept/design - 10 years ago
That donut could be just a 90° segment. (Or 120°, etc.) That way you can get back to a simple axle and don't need a large lazy susan bearing. Lots of interesting ideas since I last peeked into this thread.by Dale Dunn - Polar Machines, SCARA, Robot Arms
Re: ABS print speeds? - 10 years ago
I've printed ABS successfully at 150mm/s, but needed very high temperatures to get there. IIRC, I was running at 240°C, which is just short of damaging my MakerGear hot end. In the neighborhood of 220°C, I can print at 100 mm/s, but quality is still suffering. I'm usually not that worried about cosmetics, so I run at 90 mm/s quite often. Faster than that I run too high a risk of finding some resoby Dale Dunn - Printing
Re: Z axis with 1 stepper motor over belt - 10 years ago
It has been done to a Prusa Mendel before, but I can't remember by who. The original Sells Mandel used a single motor and belt to drive the screws from below. However, I think you might also consider a belt driven Z axis. The screws cause the famous wobble problem, and speed limitations. The downside to the purely belt drive system is that a way must be devised to keep the Z axis from falling whby Dale Dunn - Mechanics