|
Kaiser Schnitzel posted:Is there a good YouTube or somethin on how to correctly use the digital calipers I have? I can get relatively different measurements of the same part based on which way I hold the calipers and how hard I squeeze the jaws against the thing. Just keep practicing. You shouldn't have to squeeze hard at all. How much difference are you seeing? More than the accuracy range of the calipers? And are you measuring solid flat things or irregular or mushy things?
|
#
?
Jan 9, 2024 01:25
|
|
|
|
| # ? Apr 30, 2024 05:06 |
|
|
That's calipers! They read to like 0.0005" but imo are hard to trust beyond 0.005". If you get a 1 and 2" gauge block or a 1-2-3 block you can get a feel for how tight to squeeze to get the 'correct' read but a micrometer is always best for targeting a precise measurement.
|
|
#
?
Jan 9, 2024 01:29
|
|
|
That’s why I went to vernier calipers, chasing zeroes on digital ones was great bait for my anxiety disorder. Thread related, we got some fun new CATIA design tools in the SOLIDWORKS channel so I’m gonna go whole hog on that. If you’ve got any intro to CATIA resources please share!
|
|
#
?
Jan 9, 2024 02:09
|
|
|
A rule of thumb that I follow is that the squeeze is part of the zeroing. You've zeroed at a certain force, so match that force when measuring. Not so much that there is one true force but the consistency is important.
|
|
#
?
Jan 9, 2024 02:15
|
|
|
Here is a useful little blog post about how to do it correctly https://www.designreview.byu.edu/collections/getting-the-most-out-of-digital-calipers But yeah, recognizing the limits of your measuring technique is an important part of metrology. I ignore the last .0005 on my digital calipers, because I've used dial calipers and can see all the different ways that I can make the needle wobble that much. But I'll trust them to 0.001~2 assuming I've wiped the jaws clean and the object isn't soft and I'm reading it square. Or you could just be like Adam Savage and only trust your calipers to .015 because you don't understand how to swing it  https://www.youtube.com/watch?v=sX6qbm7uzsc&t=409s
|
|
#
?
Jan 9, 2024 02:32
|
|
|
Sagebrush posted:Good quality calipers are the first step. I think Mitutoyos are the best, but these are about 1/3 the price and almost as good: https://www.amazon.com/iGaging-ABSOLUTE-Digital-Electronic-Caliper/dp/B00INL0BTS That may be more than I need and I suspect an order of magnitude more than my Ender 3 can handle but boy I’m about ready to chuck the cheapo calipers I got for something else due to the battery and constant zeroing. I’ve got that set of radial whatsits on order already, a depth gauge, and a pocket steel rule with one of those clip deals on it so I should be mostly set. I’ll deal with the cheapo calipers for a bit longer and swap them out for the good stuff if I keep at this. On a separate matter, how is solid works on M series Macs these days? How readily available are “extended trials” if I was to go that way? I’m pretty happy with Onshape, but the fact it’s browser based is driving me a bit insane.
|
|
#
?
Jan 9, 2024 02:34
|
|
|
Kaiser Schnitzel posted:Is there a good YouTube or somethin on how to correctly use the digital calipers I have? I can get relatively different measurements of the same part based on which way I hold the calipers and how hard I squeeze the jaws against the thing. This is why my parts always pass when I inspect them myself!
|
|
#
?
Jan 9, 2024 05:24
|
|
|
I know the spec for maximum permissible error on Mitutoyo calipers (digital and vernier) ranges from +/- 0.02 mm to +/- 0.05 mm. Depending on what you're using it for that may not matter at all, or be far too coarse, but it's something to keep in mind.
|
|
#
?
Jan 9, 2024 16:21
|
|
|
Blondihacks has a tutorial video on using/reading calipers and micrometers. It's a little long, so feel free to skip ahead to the good parts if you don't feel like you need the beginner-y stuff, but the whole thing really is a good watch. https://www.youtube.com/watch?v=v8U_gg6Qz6c
|
|
#
?
Jan 9, 2024 16:28
|
|
|
Does anyone have a good reference for organizing collaboration on projects? I'm overseeing design on our FRC robot and am trying to bring order to the chaos that is 10 high school students in OnShape. Right now it's like 100%  I'm lucky enough to be the only designer at work so I don't have to worry about Carl in quality loving up my assemblies or anything. But this is like a whole new level of potential chaos.
|
|
#
?
Jan 11, 2024 13:49
|
|
|
Yooper posted:Does anyone have a good reference for organizing collaboration on projects? I'm overseeing design on our FRC robot and am trying to bring order to the chaos that is 10 high school students in OnShape. Right now it's like 100% An age appropriate technique might be organizing the team like a scouting patrol: https://troopleader.scouting.org/the-patrol/ Everyone is going to have to get together to nominate themselves/someone and vote on who has what specific duties, if y’all already have a team captain it’ll make things easier. I imagine you have some kind of spec sheet or requirements for the competition, so you’ll want to start doing proper design reviews to compare progress to milestones if you haven’t already. Onshape has a blog post about some of its tools for collaboration, definitely click through on the assigning tasks via comments one: https://www.onshape.com/en/blog/6-ways-to-improve-your-design-collaboration-with-cad I’m not sure if that’s available on free versions, but it’s definitely worth seeing if you do. Assigning tasks during the design reviews will be crucial. If the comment task assignments are too granular or you want to keep track of them in a higher level, Trello has been a great tool for some projects I’ve been on: https://trello.com/ Make sure that you use task completion and revisions as well. Each time someone completes a design task or update (not necessarily a review task) increment your revision so you have both the Kanban board and Onshape tools agreeing that a task was completed. That’s about all I’ve got pre-coffee. Getting folks organized and ownership over specific parts or problems will hopefully channel the chaos.
|
|
#
?
Jan 11, 2024 14:38
|
|
|
NewFatMike posted:
Nice, thanks! We're using a DAKBoard with Trello for task organizing and there's a pretty good structure for the various groups. I'm lucky in that regard. I'm using this as a good design and structure : https://cad.onshape.com/documents/a...192c55299dd5099 That is a pretty complex unit broken down into digestible bits.
|
|
#
?
Jan 11, 2024 14:50
|
|
|
Ooh, good luck there. I don't have to deal with FRC stuff until next school year, but I'm expecting it to be a shitshow both for code and CAD.
|
|
#
?
Jan 11, 2024 15:44
|
|
|
This is tangential to CAD but I figure someone here can point me in the right direction.  I’m trying to sort out how to get angle of the diagonal bit on the bottom right in the picture above. That should be a bit of Trig to sort out but I don’t have enough pieces to work with as best I can tell and it’s been long enough since I’ve had to do this that I can’t recall what additional mathematical tricks I could use to get enough data to do a solve. Does anyone have a suggestion? EDIT: As far as tools on hand go I have: Calipers, ruler, protractor w/compass. Using the protractor is straightforward enough, but I'm at a loss as to how to get the angle of the piece of furniture I'm pulling these measurements from. It looks like that would be an Angle Finder, so I guess I'm off to Lowes/Ace. Warbird fucked around with this message at 17:35 on Jan 28, 2024 |
|
#
?
Jan 28, 2024 17:24
|
|
|
I don’t think that there is enough information there to solve, since the depicted shape is open, and there are no angles shown to set up a construction for a solution. But I may be wrong about that.
|
|
#
?
Jan 28, 2024 17:37
|
|
|
That's what I suspected but I remember you can get really stupid if you want to so long as you're off in "2D land". As for the shape being open, this is just the important part of the thing I'm trying to make a mount for so that's not a going concern. I've got an angle finder to pick up from Depot here in a bit that should give me plenty to work with. I've got a neat idea to extend the 15.5mm bit at the bottom there past a hair and then using a screw/nut to keep it in place on the X+ axis as pictured. Y and X- should be accounted for via fitting to the shape so the only thing unaccounted for would be Z +/- (towards/away from the viewer's perspective) which actually may be desirable so the mount could be adjusted as needed. Apologies if that makes no sense, I don't have the lexicon for this stuff nailed down.
|
|
#
?
Jan 28, 2024 18:01
|
|
|
Stop! Don't go to Home Depot! All you need is a ruler and a protractor. β = 180 - α
|
|
#
?
Jan 28, 2024 20:14
|
|
|
The drawing is just an approximation I’m afraid. Already gave my shiny new angle-getter so we’ll see how close you and my drawing were.
|
|
#
?
Jan 28, 2024 21:10
|
|
|
No, I mean you can do that in real life on the object. Put your ruler up against this piece that sticks out, then put your protractor on top of it, butted up against the bottom. Measure the angle between the protractor and the ruler. e: just realized i didn't line the protractor up correctly 
Sagebrush fucked around with this message at 21:45 on Jan 28, 2024 |
|
#
?
Jan 28, 2024 21:24
|
|
|
How can I dynamically find the focal point of an equation-generated parabola in either Alibre or Inventor? Preferably Alibre. Iirc there's a parabola tool that includes the foci in Solidworks, but I don't have access to that right now. I know I can manually calculate foci for a given parabola, but that's prohibitively-slow if I want to play with the parabola's parameters a whole bunch. In principle I can use equation-driven dimensions to locate a point dynamically in the right place on a generated parabola, and have it relocate appropriately if I adjust the parabola equation, but I'm not sure if my CAD options have all the operators I'd need for that, + i'm not mathematically-inclined and haven't done that kind of higher-level math to drive dimensions before. E: I suppose I could also generate a parabola through one of the geometric proof methods that involves a foci, like the one where you start with the focus point and directrix and draw a bunch of radii and directrix-offset lines of chosen dimension intervals, and the points where Xmm arc and Xmm line intersect are the nodes for a spline that's a parabola. That might be the best method for Alibre, which only draws equation lines with crufty plugins. Would be awkward, though, and modifying the focus point/directrix with equations might not work without me deleting and re-adding a bunch of points and constraints for each modification, alibre tends to be picky in situations like this. Ambrose Burnside fucked around with this message at 01:21 on Jan 29, 2024 |
|
#
?
Jan 29, 2024 00:54
|
|
|
Sagebrush posted:No, I mean you can do that in real life on the object. Put your ruler up against this piece that sticks out, then put your protractor on top of it, butted up against the bottom. Measure the angle between the protractor and the ruler. Well poo poo, that would be a bit easier now wouldn’t it? I’ll give that a shot after I use this fancy new angler finder.
|
|
#
?
Jan 29, 2024 03:26
|
|
|
In a stroke of fate I really should have seen coming the angle finder is too long to work with this drat end table so I just used the ruler+protractor method mentioned by friend Sagebrush. It looks to be about 110 degrees if anyone was wondering.
|
|
#
?
Jan 29, 2024 04:15
|
|
|
I want to design a greenhouse for my backyard. I used Sketchup for our kitchen remodel in 2019-2020 but having a hard time getting it to... do what I want? for this project. Is there a better program that's more turnkey and free/free trial I should check out, that's easy for morons and idiots like me to use? Don't really need exact dimensions, just layout/design that I can translate to the real world/generate ideas etc. Is Revit on a free trial a good choice, or is the learning curve very steep?
|
|
#
?
Jan 29, 2024 15:22
|
|
|
What are you planning on making it out of? Checking to see if the relevant profile is included in any tools I have on hand might be handy. Onshape is free and good. The Frames feature should be exactly what you need. The blog post below has a little video to show how it works, and they’ve got a link to the Frames elearning course in it. I’d probably check out the regular fundamentals first, but I’m not your dad: https://www.onshape.com/en/resource-center/tech-tips/use-parts-build-frames
|
|
#
?
Jan 29, 2024 16:05
|
|
|
NewFatMike posted:What are you planning on making it out of? Checking to see if the relevant profile is included in any tools I have on hand might be handy. The frame tool is awesome and feels like cheating. I did an elevated catwalk, it took me like 10 minutes to do the whole works with railings and guarding. Really amazing workflow and the cutlist is great.
|
|
#
?
Jan 29, 2024 16:11
|
|
|
NewFatMike posted:What are you planning on making it out of? Checking to see if the relevant profile is included in any tools I have on hand might be handy. Currently, about a 3ft cinder block footer (possibly with brick facade) and then wood stick a-frame on top. With polycarbonate walls/roof. 15ftx30ft or so structure. Will check this out, thanks!
|
|
#
?
Jan 29, 2024 16:45
|
|
|
Oh that might make me doing this mount a good bit easier, I'll have to take a look into that. On a related matter, how do most CAD programs handle implementing things like screw holes and so on? Given they're a standard size I'm surprised that Onshape (as best I can find) doesn't have a "generate a screw of X type" option so you can intersect with your object and remove what you want that way. Not that it would be particularly hard to do, but it seems like time wasted that you'd be running into pretty frequently.
|
|
#
?
Jan 29, 2024 18:35
|
|
|
We mostly use the star of the previous thread title: The Hole Wizard 🕳️🧙♂️
|
|
#
?
Jan 29, 2024 18:44
|
|
|
That being said, people that don't use the hole wizard are: everyone that I have to make drawings for, apparently.
|
|
#
?
Jan 29, 2024 18:51
|
|
|
tylertfb posted:We mostly use the star of the previous thread title: The Hole Wizard 🕳️🧙♂️ Solidworks has a Stud Wizard now. Both just generate placeholder holes/studs at approximate sizes for fit checks, though. They don't model the actual threads (& in most cases you don't need to, you be fair).
|
|
#
?
Jan 29, 2024 19:01
|
|
|
Some Pinko Commie posted:Solidworks has a Stud Wizard now. If you’re designing a part that will be milled, PLEASE don’t model the threads. Use the other option (whose name I forget now). If it’s for 3D printing, on the other hand, go wild.
|
|
#
?
Jan 29, 2024 19:27
|
|
|
Warbird posted:Oh that might make me doing this mount a good bit easier, I'll have to take a look into that. Modeling threaded holes is a great way to tank the performance of any particular thing, which is why I field a lot of calls from folks using McMaster-Carr fasteners because they can just download the files from the website  Onshape does have a screw library, but a Boolean operation like that is kind of backwards from most design workflows You set the hole using the hole tool in the part design and then in the assembly space you pull in and locate the fasteners to the holes. In the part design studio you just use a "Hole" feature and choose which kind you want to use. Onshape has decent tools at picking the correct fasteners. This is done because assemblies normally have bill of materials tools that part design spaces do not. Threads are not modeled because of how threads are manufactured -- off the shelf tools are used for virtually every single thread profile, so all you need to do is call out what kind of hole it's supposed to be and the position. Most manufacturing software will automatically handle tapping size drilling and thread milling/tapping. It just saves a bunch of performance and time for everyone.
|
|
#
?
Jan 29, 2024 20:14
|
|
|
NewFatMike posted:Modeling threaded holes is a great way to tank the performance of any particular thing, which is why I field a lot of calls from folks using McMaster-Carr fasteners because they can just download the files from the website At least if you download from McMaster they have STEP and Solidworks files where you can suppress/delete the thread feature for making the load on the assembly lighter.
|
|
#
?
Jan 29, 2024 21:04
|
|
|
Oh hey, that hole feature sure does do most of what I want. Thanks for the info. I don't particularly care about the screws, but insetting nuts and so on. That said, I think I can get where I need to be with this.
|
|
#
?
Jan 29, 2024 21:06
|
|
|
NewFatMike posted:What are you planning on making it out of? Checking to see if the relevant profile is included in any tools I have on hand might be handy. This is rad as hell, poo poo. Coming from SW with weldments to Fusion with fuckall, this is making me want to use Onshape more and more.
|
|
#
?
Jan 29, 2024 21:16
|
|
|
Warbird posted:Oh hey, that hole feature sure does do most of what I want. Thanks for the info. I don't particularly care about the screws, but insetting nuts and so on. That said, I think I can get where I need to be with this. Sure, use your hole tool for a clearance hole instead of a threaded one for the desired fastener and you’ll be in great shape! Embedded nuts are so choice. sirbeefalot posted:This is rad as hell, poo poo. Coming from SW with weldments to Fusion with fuckall, this is making me want to use Onshape more and more. Yeah, Fusion has a hilarious lack of features and that hole tool drives me up a wall. I LOVE HOLES 
|
|
#
?
Jan 29, 2024 21:36
|
|
|
This isn’t a particularly CAD-dey project, but it doesn’t really fit in well anywhere except for the 3D printing thread. That said: I temporarily lost most of my hearing around the new year, and it got me interested in mechanical/acoustic hearing aids that preceded modern electric aids. you know, ear trumpets, like old people use in the cartoons? the really stupid looking ones? those things. because, stupid looking or not, i was struck by how there are literally fewer accommodation options today for someone in my situation (mild-moderate and/or temporary hearing loss, or for people who can't afford conventional hearing aids) than existed 100, 150 years ago. 3D printing could make a purely-acoustic hearing device widely-accessible for a couple of dollars worth of filament/resin, but afaict nobody's designed a modern ear trumpet design that is designed to be effective and practical for day-to-day use, and that isn't just a novelty or a joke item. So I'm taking a crack at it. Hearing aids are incredibly expensive to buy, expensive to keep running in good order, and there is no budget-friendly alternative, so I want to offer one to whoever cares to print it. Ear trumpets only look like big horns you hold up to your ear for the earlier part of their history, say before ~1850 or so. As you get closer to the 20th century, you see refinements in design start cropping up more and more, design choices that let you get better audio gain from a smaller and more practical device, and which selects for human speech audio frequencies in preference to higher/lower ones as much as possible. And one of the biggest developments in that regard is parabolic reflectors being used to ‘concentrate’ sound as part of a multi-step process. By far the most common parabolic design, and maybe the most popular ear trumpet design overall from the late 19th century onwards, is the ‘London dome’. It very cleverly uses a bell-shaped parabolic reflector to focus captured sound into a secondary ‘collector horn’ that coils inside and around the bell, making the overall device basically as large as the parabolic bell, but featuring a long and sophisticated audio waveguide that would be big and awkward if straightened out. Some representative examples, as well as a tortoiseshell London dome that showcases the internal arrangement very well.   It isn’t camouflaged to look like something else mundane, or designed as a beautiful jeweler-fashioned statement piece/accessory- both of which are their own very interesting avenues of design- it’s a practical and efficient tool ideal for occasional everyday use, that prioritizes getting as much acoustic gain as possible in a device that can be held/concealed in one hand, more or less, with a design that is robust and can live in your pocket or a bag without needing delicate handling or a storage case. So, my own designs currently being tested and iterated. This was my first attempt:   All parabola, with a little collector horn and a horizontal hearing tube I took from a German example. This design was constrained by me wanting it to be a one-piece print on a resin printer, printable standing on the edge of the bell with only a handful of supports inside the tubes/under the dome, so it’s short to limit print times. Also it looks like a Diva Cup.  I used two-part silicone putty for the earpiece so I could just mould it to suit my ear. It… works? It definitely works, but not in a useful way. It’s selecting for high-frequency noises that are outside of the speech range, it’s spooky, it picks up the rustling of clothes or someone rubbing their fingers together, the sounds of coins clinking together, etc but the gain on actual speech is poor. I think it’s because of the small radius of the reflecting end of the parabola, plus the very undersized collection horn, which I made much smaller than most historical references have. Smaller reflector and collector selects for higher frequencies, but to a degree I didn’t expect. My clean-sheet MK2 redesign, which hews much closer to some historical examples in style and proportion:   This time I’ve used a much larger reflector radius and collection horn, and just cut the reflector parabola off at a convenient diameter to hold in the hand, at which points it becomes a straight-sided tube. The sides being parabolic past the edge of the collector horn does nothing because sound can’t enter from the open side of the bell, it has to bounce off the back first. Putting the listening end of the horn up and at an angle like this is also much more ergonomic to use, it turns out. This one is larger than the MK1 prototype, and I’ve given up on it being a single-piece print, it’s too hard to get the supports out that way. I split it down the centerline to get two symmetrical halves, print each floating on supports with the acoustic waveguide part facing up to guarantee a nice clean finish, add some matched alignment pins/holes to aid in assembly, and just glue the two halves together once they’re printed and cleaned up. I can juuuust fit both halves and their supports on a single large resin printer build plate, like a Phrozen 8K or thereabouts, only about an hour and a half + about 110 mL of resin to print all the parts which isn’t bad at all. I have high hopes for this one being closer to a properly-practical ear trumpet, if everything works out I want to attempt a design with an off-axis reflector, where the collection horn is off to the side and the bell is unobstructed clear back to the reflector, because such a reflector could be a semicircle/ ‘D’ shape in profile, which is ideal for two headphone-disguised ear trumpets worn on the head, one for each ear, an arrangement called ‘auricles’. Hence the parabola focal point stuff. But I'm getting ahead of myself, once I have a robust London Dome that's easy to print and use i can worry about auricles
|
|
#
?
Jan 30, 2024 04:30
|
|
|
Sick bong bro Kidding, that's super interesting.
|
|
#
?
Jan 30, 2024 04:45
|
|
|
That is very cool, and your projects are consistently cool - please keep posting them.
|
|
#
?
Jan 30, 2024 19:42
|
|
|
|
| # ? Apr 30, 2024 05:06 |
|
|
Ambrose that's super neat! I am very curious how different geometries highlight different ranges. Is it all varying the geometry of the parabola, or might a hyperbola or non-conic section like a catenary work for different sounds?
|
|
#
?
Jan 31, 2024 20:43
|
|