Screwdriver
Member
- Messages
- 10,549
I can't help with Sketchup, but if you want to use something more civilised
That's great, can you do me a "more civilised" version of this:
- Thread starter ukracer
- Start date
That's great, can you do me a "more civilised" version of this:
Dr.Al
Forum Supporter
- Messages
- 2,354
- Location
- Gloucestershire, UK
I wondered how you'd respond when you read that comment!That's great, can you do me a "more civilised" version of this:
I've said it before and I'll say it again: I'm very, very impressed by what you (and others) can do in Sketchup. However if I had the urge to draw something like that, then I'd use a parametric CAD system, as I'm sure the designers of the original did.
Screwdriver
Member
- Messages
- 10,549
I wondered how you'd respond when you read that comment!
I've said it before and I'll say it again: I'm very, very impressed by what you (and others) can do in Sketchup. However if I had the urge to draw something like that, then I'd use a parametric CAD system, as I'm sure the designers of the original did.
Sketchup is for sketching. If I had the original plans for the JWST, I would use a parametric or "professional" 3D drawing system. Then from that, I would still have to modify the design to allow it to be 3D printed and the scaled items to look a reasonable facsimile while still functioning by folding/hinging etc. FWIW, the biggest problem I had was getting a model part to a state where it was physically possible to print at all. As an aside, the 40:1 scale is chosen because that just allows the largest single item to print diagonally along the bed.
I looked at Fusion but the sheer complexity means I would certainly need to invest at least 6 months while at the same time, it would NEVER allow me to do a "hack, looks good enough" design. They made the decision easy by cutting out the best parts of Fusion (generative design) which would have made the effort worth it. IIRC they chopped out a ton of stuff from the "free" version one assumes because they tricked a large enough group of people it was going to stay free.
What Sketchup has allowed me to do is take a bunch of photographs and one isometric view to make a reasonable model.
It's a pretty good fit if I say so myself.
I have to say having tried a number of 3d modelling programs, I doubt if any of them would allow an amateur user to make a printable model. Look at the ridiculous compound angles on this thing. I am tempted to challenge anyone reading this who thinks they can do it AT ALL with their "civilised" program to design for print one of the parts I am least happy with, say, the front pallet.
Here you go, I have (inadvisedly) released my drawing which will make things considerably easier. Here's what I used:
I still haven't decided what to do with the model. I had hoped to sell them but the price would be ridiculous just for the print time so I'd have to find some way of releasing the model without getting ripped off.
ajlelectronics
Forum Supporter
- Messages
- 9,858
- Location
- Gloucester, England
Sketchup is for sketching. If I had the original plans for the JWST, I would use a parametric or "professional" 3D drawing system. Then from that, I would still have to modify the design to allow it to be 3D printed and the scaled items to look a reasonable facsimile while still functioning by folding/hinging etc. FWIW, the biggest problem I had was getting a model part to a state where it was physically possible to print at all. As an aside, the 40:1 scale is chosen because that just allows the largest single item to print diagonally along the bed.
I looked at Fusion but the sheer complexity means I would certainly need to invest at least 6 months while at the same time, it would NEVER allow me to do a "hack, looks good enough" design. They made the decision easy by cutting out the best parts of Fusion (generative design) which would have made the effort worth it. IIRC they chopped out a ton of stuff from the "free" version one assumes because they tricked a large enough group of people it was going to stay free.
What Sketchup has allowed me to do is take a bunch of photographs and one isometric view to make a reasonable model.
It's a pretty good fit if I say so myself.
I have to say having tried a number of 3d modelling programs, I doubt if any of them would allow an amateur user to make a printable model. Look at the ridiculous compound angles on this thing. I am tempted to challenge anyone reading this who thinks they can do it AT ALL with their "civilised" program to design for print one of the parts I am least happy with, say, the front pallet.
Here you go, I have (inadvisedly) released my drawing which will make things considerably easier. Here's what I used:
I still haven't decided what to do with the model. I had hoped to sell them but the price would be ridiculous just for the print time so I'd have to find some way of releasing the model without getting ripped off.
Cults 3D.
Screwdriver
Member
- Messages
- 10,549
The problem is not how to sell the model (about 100 individual .stl files). It's more about how to stop anyone else from copyng it and selling it themselves. After all the business enterprises I have been ripped off for, that would end me.
Cheers bud.
This looks like a very useful thread for me as I can mess about with various programs till I get one that suits me.
Apart from that big props to screwdriver as I can drill out as soon as I am near my mill.
I almost did....lol
I replied hours ago but forgot to press post..
(just sent the reply)
northwest
Searching for the Holy Grail.........
- Messages
- 5,822
- Location
- Manchester UK
Well you all know where I am and as I have mentioned, yesterday I went down for an ultrasound. Chatting to the Technician I asked him the plan? Oh he said, need to measure some bits like Arteries and such. Righto and how do you do that? Well, he said I need your height and weight and the scanner will work it all out from that. Fek knows how much the machine cost, that is some pretty impressive math. We are all getting far too clever for our own good.
Screwdriver
Member
- Messages
- 10,549
Cheers bud.
This looks like a very useful thread for me as I can mess about with various programs till I get one that suits me.
Apart from that big props to screwdriver as I can drill out as soon as I am near my mill.
Depends what you're after. For model making and CAD, you're probably better off with Fusion or Blender. Sketchup is legacy software. I use the 2017 version locally because I don't want to be tied to cloud connected software. Getting it to make a .STL is also not really what it was designed for and I use a plugin.
If starting from scratch, I dearly wish I was as comfortable with Fusion but as I said, even if I was, the fundamental philosophy is that you know what you want and can use that software to make it. I never know what I want so I use Sketchup to sketch objects in 3d, tweak the design, copy/paste (impossible in Fusion!) and I have been doing it for so long now (20 years??), I am very (very) quick with it. Speed is of the essence because I do my own designs, even if some of them are copies of buildings, repair items or even giant telescopes.
That's not to say I am particularly skilled, a trained Sketchup user would run rings around me but I have developed my own path with it and that's how I like to work. Too late to change my workflow now, well, too difficult to unlearn/relearn and not enough of an upside with anything I have seen yet...
This is useful.
To be honest I wanted to have an STL of that model you did 16mm deep. But I was hoping to learn how to do it in sketchup (purely as I seems it might be more intuitive than fusion.
I can draw an 118.10mm round in fusion and extrude it. Placing holes at strategic points. But it would take me hours and might not be accurate.
There is a way using a scan but I don't know how to do that yet.
I have just learnt my sister in law has less than a month to live and i am not sure how hard its going to impact my wife, so i am trying to do things that keep me close to her but are useful. But also keep my mind occupied as i lost my mom in february my dad does not want to be here anymore and it feels like everything is crumbling around me and i feel guilty.
So I am confusing things by wanting to learn . Bit like learning to swim by jumping off the 6 metre board....lol
Screwdriver
Member
- Messages
- 10,549
This version of the model will be easier to work with. The dimension version had a lot of solids taken out of it. It is a line drawing effectively. There is an stl . I have added a 1mm step because that's what the picture looks like but since the later picture shows a broken part suggests the whole ought to be closed in the centre, I wonder how useful any of this is.
Just ask and I'll send a 3d print...
Just ask and I'll send a 3d print...
Screwdriver
Member
- Messages
- 10,549
We all live in the shadow of death. I discover my own fate in a couple of weeks. Doesn't look promising.
very useful mate.
At least I can see what I am going to get if I drill the holes in the right place.
I have just got back home and tried printing the STL but the holes in the inner ring are free floating though.
I am now on my PC rather than phone and re read the comments. But as soon as I sat down on the PC my scan was still on screen and I can see what you mean about later pics show the center as a solid.
I acual fact I tried not to confuse everyone but by doing that I forgot to explain the 12 holes are in one solid piece of steel. (The center ripped out) so from the top view there are stepped holes 17mm wide and 11mm through hole set 8mm down.
It is held in place by capheads which fit fairly flush
Misterg
Member
- Messages
- 1,162
- Location
- North Wales
That sounds very ominous...
Here's hoping for good news.To go back to the original question...
AFAIK: You can't measure a picture with Fusion360 (or any of the other 3D CAD programs that I'm aware of). All you can do is import it onto a selected plane (INSERT -> CANVAS in F360) and use it as a template to draw over by eye, taking advantage of your known dimensions (much as @Dr.Al 's little tutorial above).
I would start by drawing a circle at the origin at your known OD *before* inserting your picture as a canvas onto the same plane. During the canvas insertion process, you get to drag and zoom the image until it is a good fit to your OD circle. (There is another method where you insert a canvas then 'calibrate' it to a known dimension.)
It's not a particularly accurate process, but you can improve things by adding any dimensions you can actually measure, and knowing that you expect all diameters to be concentric; holes equal and evenly spaced, etc, and looking for dimensions that are close to round numbers (metric and/or imperial), but the last one can be a bit dangerous.
I've attached a f360 file which is a series of sketches traced over your original image in case you want to play
(Note that you will need to switch the 'canvas' on and off to see the sketches properly - it also has an 'opacity' value if you edit its settings.
*I don't know why the holes and polygons that they're based on as showing as unconstrained (blue / brown) - I think that they are and can't move them, but I wouldn't be happy normally.
(Your last reply arrived as I was typing.)
Screwdriver
Member
- Messages
- 10,549
Sorry my fault. I left a bulkhead inside the stl.very useful mate.
At least I can see what I am going to get if I drill the holes in the right place.
I have just got back home and tried printing the STL but the holes in the inner ring are free floating though.
View attachment 360390
I am now on my PC rather than phone and re read the comments. But as soon as I sat down on the PC my scan was still on screen and I can see what you mean about later pics show the center as a solid.
I acual fact I tried not to confuse everyone but by doing that I forgot to explain the 12 holes are in one solid piece of steel. (The center ripped out) so from the top view there are stepped holes 17mm wide and 11mm through hole set 8mm down.
It is held in place by capheads which fit fairly flush
Too late now but here's the fix.
forgive me if I seem ultra thick and I am tempted to clamp the old one over the new blank. BUT as I said to Hitch I love to learn, even if it does not last long in my head. But what exactly does the 100mm signify.
It might be that I can see the wood for the trees but I am looking at the different diagrams and sketches etc to see what I can understand (nothing so far)
Its most likely as I am expecting to see different figures.....for example taking the co-ordinates from the center might be a bit longer but would make sense to me (I think)
So from the center ......*HOLD ON**** sparks came from my head and I "thinjk" I am getting it.
Screwdrivers measurement are all taken from a datum line 100mm from the center in both X and Y axis... So I find the center and come out 100mm.
Along the center line I come out 100mm along y axis and then I go up 149.21 (y axis )and drill the top hole. to drill the bottom hole I go back to the 100mm and go up 50.4mm and drill the bottom hole.
always working from the imaginary 100mm lines???
Have I finally got it??? lol
Its most likely as I am expecting to see different figures.....for example taking the co-ordinates from the center might be a bit longer but would make sense to me (I think)
So from the center ......*HOLD ON**** sparks came from my head and I "thinjk" I am getting it.
Screwdrivers measurement are all taken from a datum line 100mm from the center in both X and Y axis... So I find the center and come out 100mm.
Along the center line I come out 100mm along y axis and then I go up 149.21 (y axis )and drill the top hole. to drill the bottom hole I go back to the 100mm and go up 50.4mm and drill the bottom hole.
always working from the imaginary 100mm lines???
Have I finally got it??? lol
- Messages
- 13,442
- Location
- England
You could work from the centre... Set the dro to 0,0 on the centre, wind it out to -100,-100 and zero it again.
Then the above coords will work.
Or work from an edge.. setup finding the edge on x, Set the x dro to -half the diameter of the blank, same on the y. Wind out to -100,-100 and zero it off again to use the supplied coordinates.
Then the above coords will work.
Or work from an edge.. setup finding the edge on x, Set the x dro to -half the diameter of the blank, same on the y. Wind out to -100,-100 and zero it off again to use the supplied coordinates.
If I could get out to workshop I could trial and error check it. But baby sitting again.. Lol
So trying to prepare my head to make it easier later.
