I’m brand new to freeCAD and have no idea what I am doing. I want to design

https://dasai.com.au/products/mochi-helmet

The above helmet but do not need the speaker holes and want it to be wider as I plan to put a bigger screen as shown in the image. The screen also has holes in which the inside of the helmet to hold the screen in place.

How can I go about designing this? I was thinking of using a rectangle but am unsure on how to make it all round.

So I have like 10 years experience using CAD, started with Creo, Solidworks, and Spaceclaim all in school. Then several years of NX experience at work. Lost access due to leaving my job, and don't like the idea of spending 1000$ a year for CAD software...

Been binge watching mango jelly and adventures in creation. I feel like I have a good foundation, but looking for some tips from pros. Things you wish you knew sooner. Bad habits to break early. How I can help the community/degelopment.

Thanks, so excited and grateful this community exists!

I'm in a sketch, setting up constraints - I just want to select one of the properties from a VarSet - is there a way to do that?

This is the sequel to my coldboot post here. I could wax poetic about all the engineering and design work that went into this tiny little subproject of the Laneway House project, but that could get a tad monotonous. Suffice to say that I spent some considerable time dwelling on the minutae of how air flows through ducts and how it can be made to flow more freely by paying attention to sizes and shapes. Also construction methods, and for that I decided to go old school.

In the good old days, that is, when they built those glorious old houses, they had a pragmatic way of doing cold air returns: just nail a piece of sheet metal across two floor joists in the basement and there you go, a duct. This is still allowed by code, at least most building codes, but it's seldom done that way any more. For one thing, joists got a lot more complicated with all kinds of obstructions in them, and for another, it's not the ideal cold air return. Wood causes a lot more air friction than galvanized steel, and the whole arrangement can be a bit leaky and rickety. Leaks don't actually matter that much for air returns - you're just trying to get the air back, after all, and don't much care if it mixes with other air on the way - but in some circumstances it matters, like going past the kitchen, where smells could be picked up and circulated back through the whole house. You also don't want critters setting up home in there.

Anyway, wooden air returns are a thing. After modeling up that sheet metal cold boot I thought about exactly how it would be fabricated and it's actually a bit tricky. Maybe expensive. I decided to do the job in plywood instead, then everything gets nice and simple and easy to build, while being just as good as the metal version as far as I can see.

There are a couple of interesting design problems I ran into. First and foremost, there should be no constrictions in the return air path. Which is to say, the square inches of the path profile should never be less than the cross section of a return air branch. And preferably a bit bigger, because the air has to bend around when it enters the boot and that in itself is a kind of restriction. This is ameliorated by making that part bigger, maybe 20-30% bigger cross section. Rule of thumb territory, because actually working out the fluid dynamics in detail would b a whole project in itself, not for the faint of heart. And not necessary. I just need to get into the ballpark, then experienced HVAC people will look at it and either nod or swear. If the latter, then back to the drawing board.

Without further ado, I give you Cold Boot 2:

Cold Boot 2

So... what should jump at you right away? Red alert: I cut away the bottom of a stud, so what is going to support the wall there? A bearing wall must be supported everywhere ,to keep the the house from sagging or even disintegrating in an earthquake. No good. So what about that?

The answer: plywood is used in a structural role here. There are two plates of half inch plywood on edge sitting longwise under that little 2x4 header, and the header sits across the edges of those. The stud sits on top of that, which should be totally solid. Plywood is incredibly strong on edge. An ordinary 2x4 stud can support about 3 tons of weight when the weight is applied in the direction of the grain (provided the stud has lateral support to prevent buckling). Plywood is way stronger per square inch than bog standard SPF, so this support scheme is adequate for sure.

Those two pieces of plywood reduce my "duct" size somewhat, but the cross section remains larger than the duct cross section everywhere, so that's fine. Then to transition from that slot into the duct there is a piece of plywood with an oval cutout. Something you could do in two minutes with a jigsaw, whereas sheet metal would need a lot more fiddling and not be any better as far as I can see.

There is a diagonal piece of plywood stuck in there, with the intended role of preventing the air from flowing into the corner and swirling around there, creating friction and noise.

What I did not show in this model is the cutouts in the sill plate and concrete that make this whole concept work. Without that it is really hard to get from the attic to the basement, short of a duct chase that invades the living space. I didn't model that only because it's a bunch of work I have to do - create the cutting tool and get in there and use it on two distinctly different objects. Not a big deal, but right now I would rather be posting than cutting. Basically, I will just extend the sill plate cutout that is already there to let electrical cables get past the ends of the structural steel beams. And I will also cut away some concrete, in a way that I have convinced myself will not reduce its load bearing capacity or longevity all all.

With the sill plate and concrete cut away, the air path will then reach that little space between the last joist and the concrete wall, which by complete accident happens to be the perfect size for the grill that will go along the ceiling. If that gap were any smaller, and nothing prevents that, it's just a random relationship between my 1 ft joist centers and the width of the house, then I would have to cut a joist and add support for the cut ends. Which I still might do anyway, because it's pretty easy, and there is one more major detail still to address.

That detail being, how do I route electrical cables past this contraption? A whole fistful of cables has to run through there on its way from the electrical panel on the main floor to the kitchen in the basement. I could drill through 2x4s to get there, but that's a lot of holes, or I could run the cables up through the soffit, or probably a few other possibilities, but all of these ideas make the cables longer, and that eats electricity. Not much, but enough to bother me. So what I am going to do, probably, is just route the cables right through the duct vent space. The grill will be two or three times the required size there, so flowing its way past some electrical cables will not be a problem. To sweeten the deal, I can run those cables through a little conduit, just a piece of PVC pipe. Simple, easy and cheap.

OK, modeling this up went pretty fast. Much more time was spent researching and brainstorming than modeling. That's a nice change. But I have to say that the modeling took three times as long as it should have, because bugs. Array elements that won't come back after being toggled invisible, TNP (still not gone), sketch edge renumbering (another issue just as bad as TNP, but so far not getting any developer attention like TNP), external links broken because of loading documents in the wrong order, etc. Painful, really. Here's hoping that all of those issues go away pretty soon, because everybody is going to hit them sooner or later if they haven't already. There is nothing obscure about these bugs and they are not fun to have popping up again and again.

But still, the bottom line is, FreeCAD is awesome.

Postscript.

Now I am going to fill in some of the math behind my cold boot design. I promised not to, but sometimes I fib.

A "7 inch" oval duct is actually 9.125 inches wide. They call it 7 inch because it is supposed to be equivalent to a 7 inch round duct. Which it isn't, it is actually about 30% worse than a 7 inch round duct according to people who have looked into this deeply.

A 7 inch round duct is about 38.5 square inches in cross section, compared to a 9.125 inch oval duct cross section, which is 27.4 square inches, or about 30% less. Oval creates more turbulence than round, but I have no idea how much extra turbulence so I am just going to go with the 30% worse number for now. In any case, my 7 inch oval duct is arguably overkill for this return branch because this is only one of three return branches, all of which feed into a single 7 inch trunk.

Anyway, I must not go below that 27.4 square inch profile anywhere on the path through the boot. Because the boot has a few square edges, plus the air has to change direction, I arbitrarily tack on another 10% in cross section and use 30 square inches for my baseline goal.

So, what is the cross section of the space between two wall studs at 16 inch OC? Easily calculated, it is (16 - 1.75) * 2.5 = 35.625 square inches. Bingo! Comfortably more than the 30 square inch cross section I am designing to. That is with my two plywood header supports in place. Which means I don't have to do anything special there, I can just use that gap between two studs as my channel up into the metal duct. This immediately widens out to 3.5 inches, or nearly 50 square inches after exiting the header support. I can soften the transition between the two spaces by ripping the plywood edge to 45 degrees, reducing turbulence by a small but satisfying amount.

Now, going the other direction, why did I feel the need to widen the vent out to two stud spaces when one already seems to be enough? Simple. The air coming into the slot has to bend 90 degrees, twice. That's a whole lot of air friction. It helps a great deal to double the size of the path. As I understand it, air friction increases by much more than a linear factor versus velocity. I seem to recall it's a cube relation, but even if it is only square then I reduce the air friction by a factor of 4 by doubling the slot width. Worth.

On top of that, doubling the slot width only costs me 4 little pieces of plywood and a scrap of 2x4, plus a modest amount of carpentry, so definitely worth it.

(edit) My recollection of the nature of air friction was more or less accurate. "Air friction has terms proportional to the square or even higher powers of the velocity." Going through a grating and around corners will be turbulent for sure, and higher order terms most probably apply. But for my purposes the square relationship should be appropriate. This does draw attention to the advantage of maintaining laminar flow through the duct path.

Just as the tittle said I am looking for other software and or tools to use along FreeCAD.... such as conversion tools, PCB design ect. I am on Linux (Ubuntu) lates build ATM

Like I wanna make a base but how do I do it?

If you haven't tried it yet, asking chat GPT your free CAD questions in plain English is surprisingly productive. You get back plain English answers that usually are the correct solution. It's like having an expert.

Just thought I'd mention it, a lot of the questions people ask here they could probably get a quicker answer and not load down the forum.

Is there any place to download the TechDraw templates from the current and/or previous versions?

I am working on a project wich is made of several pieeces.

i began the project with Freecad 0.21, it did not accept merging pieces together.

Freecad 1.0 does allow that but it uses to crash easiily after reaching some level of complexity.

I do have it installed by means of flatpak repository, i am not using the Appimage and i got 1.0 as an update.

Does exist any kind of adjustments i be able to perforn on my system aiming towards some stability?

I am new to FreeCAD and was wondering if it has a feature similar to
Fusion 360. In Fusion, every measurement is assigned a short ID, which
can be referenced in other measurements across sketches.

For example, in
the first sketch of a part, I might define a length, and later, if I
need another dimension to match that same length, I can simply enter the
ID (e.g., L1). This way, the measurement remains consistent even if the
original value is changed.

Does FreeCAD offer a similar functionality? If so please explain it simple because I installed it yesterday.

I am trying to make this whole design parametrically generated. There are two pads, the wedge shape and the rim segment adjacent to it. I am trying to polar pattern these pads, but the number of occurrences will vary based on certain parameters.

Filleting is applied before patterning because I'm not sure if it's possible to do so after, since the number of wedges is variable.

Here's a link to the file if anyone is interested: https://filetransfer.io/data-package/66k0qqV9#link

When I try to pattern the two pads and filleting the max number of times with no overlap at the end, everything is fine. You can see the gap in the rim since there is slightly more than 1 pattern width remaining.

https://preview.redd.it/pweyhbkorg4e1.png?width=589&format=png&auto=webp&s=96b0d65616d1b65adbab9425f3ed8f68248d2498

Unfortunately, I need them to overlap. But when I add one more instance of the wedge, the pattern just turns into the filleting only (although it's mostly right angles, except for the curve at the bottom of the wedge). It also doesn't include the additional instance of the filleting that would overlap. There are no errors or issues shown in the report view.

https://preview.redd.it/g9hh3dsqtg4e1.png?width=784&format=png&auto=webp&s=50123846628f782a1d347b53dfeef891cdf6f223

Trying to pattern just the pads while the filleting still exists on the first instance works fine for a non-overlapping number of instances, but when I try to add the overlapping one, the drawing is not updated and I get the following error:

11:50:07 <Part> ViewProviderExt.cpp(1308): Cannot compute Inventor representation for the shape of Retainer#PolarPattern: Bnd_Box is void

https://preview.redd.it/2uot7tbgtg4e1.png?width=806&format=png&auto=webp&s=90d698bfd5e8fec6b24561435638287fd9c04e51

However, if I delete the filleting and pattern just the pads, it works fine even with overlap.

https://preview.redd.it/fuq79klssg4e1.png?width=748&format=png&auto=webp&s=96229fd80d1d08add1f46ecc6c9b216f3c2b7239

Long story short, moved here from blender because im tired of worriyng about topology. Watched basic operations and thing tutorials, modeled simple details. Are there any good advanced tutorials with modeling curved or complex shapes and etc.

I've been using SolidWorks for almost 20 years, and I've made several attempts to start using FreeCAD, but so far, I haven't managed to stick with it. With this new version 1.0, I want to give it another try, but I'm encountering some minor issues that I can't seem to solve. For example, I'm having a lot of trouble getting edge flanges in sheet metal to take the shape I'm used to in SolidWorks. Do you know how I can make these bends have a closed corner?

Thanks!

https://preview.redd.it/x3hpfnncpf4e1.png?width=1143&format=png&auto=webp&s=8b456c3bac14a41a27bc3de12a07e0367df34f6c

I readily admit ignorance.. I hoped MangoJelly could help but I guess he is creating not printing. I need to create a file of the clone so a friend can test print.

I have successfully (I think) created (a body) in Part DESIGN WB... Went to DRAFT and scaled down clone of a BODY... (at least the sheep head is there and the image looks like the parts of the body) at least it looks like the larger one...

So how does one use this clone to 3D print (resin) or send to an outside printer for printing? (I'll guess somehow... I need to create /save an STL file ONLY of the clone.)

My friend does not use FC so he did not know.

Thanks in advance for the help. I got a new laptop and installed FreeCAD 1.1.0 dev. Now the sketch contraints appear as red letters in black boxes. I can change the red but I can't figure out how to get rid of the black boxes.

edit: should mention this is Windows, LG gram with Intel ARC graphics.

I have read suggestions my graphics drivers are out of date (they were, but nothing changed) or that display setting, in particular anti-aliasing, to no avail.

Any suggestions?

edit: this is a bug in the dev version. I have been running dev versions forever (including my old machine) and not encountered this. It turns out my new machine was 1 dev version ahead of the old machine but I thought it was the same version.

I've been digging through documentation, and looking for posts or videos, but I haven't found a specific answer.

A time saver I use sometimes is to create multiple shapes in a single sketch and then pad some of them and pocket others. An example would be a small box with screw holes at the corners. In a single sketch I would draw four squares, one at each corner to be material for the screw hole. And then draw circles inside the squares for the screw holes.

Then I'll first pad the squares down into the box, and then pocket the screw holes into the new pads. The problem is selecting the squares. You have to control select all four sides of each square, 16 mouse clicks.

I figured there has to be some key combination that will force it to select all connected wires of an element in the sketch. I thought maybe I can select all and then just control click the circles to unselect them. Nope. That didn't work.

So is there some simple trick that I'm missing?

I am in the midst of modeling the hvac for my Laneway House, first draft is here. Naturally this changed a lot subsequently - filling in the details, simplifying and optimizing, and incorporating some excellent design suggestions from right here on the sub. My basic prescription being, first do the model, then do the research, I did get around to researching my design features on the interwebs. I soon discovered that the vast majority of hvac pros absolutely hate the idea of having a return air in the kitchen. One variant of US building code even explicitly forbids it, but most building codes including my local one allow it. Whether it is a good idea of not is another question, a very good one.

My first draft has a return air near the open plan kitchen. Close enough to call it "in the kitchen". I decided to leave it there (perfectly compliant with code where I am) but put a damper on it and design in an additional cold air return further away. In general, more air returns is better, subject to not having the walls so full of them that the R-Value drops below code. So I set out to find a place to put a new return.

That wasn't so easy, far from it. The issue is, these big concrete walls are in the way of running ducts into the basement. Got into some serious navel gazing over that one. Am I going to cut holes in the concrete? Embed ducts in the concrete? Or what. Well, the what finally occurred to me in a blinding flash while asleep (seriously, happens). It turns out that only a slight modification is required to my concrete basement walls, similar to the mods I am already doing, to wit the "notch" all the way around the top inside to support the outside ends of 2x4 joists. I just make that notch a couple inches deeper and voila, I have a usable air path through the concrete wall.

The next part of this is, what does the sheet metal look like that goes through my new hole in the wall into the basement, suitable for a nice big air return grating in the ceiling. Here is my first draft of a solution:

https://preview.redd.it/1tpq2pjrlb4e1.png?width=1920&format=png&auto=webp&s=3b515a37283de52b80397ff2c5f1bf07605e0282

The bottom part is to be custom fabricated by a local shop and standard oval duct fits into it. This is what it looks like in context:

https://preview.redd.it/ekj9tpkylb4e1.png?width=1920&format=png&auto=webp&s=ccc68c845bebb47d52f6d2e7a307ae4f9fd2d148

And I will have a long narrow ceiling grill on the bottom side of that floor. This is already looking workable and buildable, but I think I can do better. I dub this the "cold boot" because it is a cold air return boot fitting. Also, cold boot means something special to us computer nerds, so there you go.

So what is wrong with this?

• It hits the structural steel beam on the left
• It constricts the cross section below the cross section of the duct
• It blocks the shortest path from the electrical panel to the kitchen
• Slight modeling errors
• Not very much else

So now I am cooking the next iteration that I hope will remedy all those points. Fascinating topic, right? Maybe not... but I am sure, quite interesting to those who are quite interested in this sort of thing.

Things I had to worry about in this design:

• Don't constrict the air and make it whistle
• Don't reduce the structural integrity of the wall
• Don't crowd out the electrical panel
• Don't block the (many) wires between the panel and kitchen
• Don't run into the structural beams
• Don't make me move the windows
• Don't require an invasive chase inside the living space
• Don't make it hard to fabricate
• Do be far from the kitchen exhaust hood
• Do have a large grill to serve the entire basement
• Do line up with the gaps between truss chords
• Do provide a pleasing aesthetic for the inside grill

So, this model isn't great but it served the important purpose of convincing me that it can be made to work and that there is a good solution in there somewhere. Seeing the thing in context made a huge difference. The power of CAD, and thanks again to FreeCAD.

After another creative sleep some new ideas arrived that I am modeling now. I expect this will take the design from merely workable to actually elegant. Meaning not only working better, but looking better and being easier to build.

I have been trying all the tutorials I can find with no luck. Some leave me with total garbage and some get me close. The image below shows my latest conundrum. There are no blue squares and text aligns to the line in what seems randomly. In addition, the text doesn't always left or center align.

I'm pulling my hair out and about to give up and return to SketchUp. Any help would be greatly appreciated! If someone lets me know how, I can upload a copy of the SVG file. Thanx.

I have found that the Start Page on build b39380 is not displaying the "thumbnail" images for both the Recent and Example file links:

build 39380

b39109 v1.0.0

(The above screenshots were just now captured within 30 seconds of one another. These are the .AppImage builds from GitHub.)

Linux Mint v22/Mate:

my system

Has anyone else experienced this?

I was looking in the gear work bench and timing gear looks closest but not right.

I'm trying to design a jig to cut bicycle chain rings using the drill press and band saw. (It's what I have)