ABOUT ME

I live in a camper van with a West Highland Terrier for company.
My passion is creating images but it is a work in progress.
I am always willing to share what knowledge I have and can be contacted through the comments on this post or e-mail ADRIAN
ALL IMAGES WILL ENLARGE WITH A LEFT CLICK

Thursday 18 November 2021

ONE PROBLEM SOLVED.

 I have solved one problem, not to worry there are plenty more to go. 

I decided to remodel the flywheel for the little engine. It's not a big job in CAD software but I like to have a pretty picture as well as a drawing. Now if I make the spokes in FreeCAD and do a polar array of them to make several spokes it stops the computer. I have struggled on and got a result but it's a pain, worse than trying to get AutoCAD to accept my password. As far as the latter is concerned I wouldn't mind too much if it was my password but it's not it's theirs. Bastards just don't want a poverty stricken OAP having a play with their software. 

Look at this.

This is what I've been having to put up with. 
This is what I now manage, or the computer achieves. A gorgeous rim and the solution with all things computer is all down to the file system one uses. Pop crap in get crap out. Years ago I found that I could swap (obj. files) between FreeCAD and Blender. Happy it happened I carried on doing so with the occasional foray into (.stp) for folk wanting summat for a 3D printer. I've been doing it all wrong. I knew there was something amiss so this morning I tried different file formats. After several failures I happened on one that works and one that both Blender and FreeCAD can accept. It's STANFORD (.ply). I bet there's a downside but it does this job to perfection. I don't know why it works but am desperately trying to resist the temptation to delve deeper and find out.
I now have adapted and model one spoke in FreeCAD which seems very good at the job and fire it into Blender which is drop dead perfect for arrays. I wanted elliptical section spokes which is hard to do in Blender. It's a piece of piss in FreeCAD.
Here we have three sketches, the upper ellipse is offset by the spoke length required the ellipses are on one plane and the green line is sketch 002 on a plane at 90° to it. Easy peasy, lemon squeezy. Then we go to 'Loft' press the tit with one ellipse selected and bugger all happens again. You have to tell it that you want the green line and it will shoot an ellipse, or any shape up it. Then you have to select 'Multisection' select the sketch remaining and you get a perfect elliptical sectioned tapering spoke to let Blender have a go with, where, as I said it does the array perfect.
A perfect Additive Pipe. I know I said it lofted but when I get the result I want it changes it's name to additive pipe. Not addictive pipe, that's what the Bidens use whilst molesting children.

Going back to the rim FreeAD I like. One quick sketch like this.
A revolve and we have the outer bit in seconds. I just have to remember to export and import as (.ply) files.

I do wish that I'd been born in the computer age but my son was and the computer teachers were next to useless when he was at school. Much like my maths teachers. I had one physics teacher who encouraged us to search out information for ourselves. I blame him for all this malarkey. To be fare the bloke was a star. He taught me most of my maths calculus, boiled it all down to the hard bit is deciding on the upper and lower parameters for integration, daft bat, at our level we were given those in the problem. He was a multilingual man with a Marxist bent. We climbed together for years and as a bonus he had a super fit daughter. The wife wasn't shabby but he only had ten years or so teaching then went climbing full time, financing his climbing by rebuilding Gardners and I got my kicks from cars and bikes. I was about as good a bike racer as I was a mathematician. 
Have fun.
 

 



2 comments:

  1. Moving to a .ply file format certainly made a great difference. Apparently it was designed to store three-dimensional data from 3D scanners.

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    Replies
    1. John, I should have tried changing the file format ages ago. I have another problem when using Boolean modifiers on some arrays. I'll see if using .ply solves that.

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