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How to Derive from an Assembly?
jack_erhart
Member Posts: 129 ✭✭
in Drawings
I have a need to be able to derive a fully assembled model into a new Part Studio for scaling the model as a whole.
Can this be done?
I have a friend that uses a program called Inventor, and that program has that feature, so I thought I would ask.
Thanks for the help.
0
Comments
How many part studios were involved in making the assembly? Could you scale each of those instead?
Is this just for a one time thing or do you need to do more work with the CAD when it's scaled?
Exporting the assembly as a Parasolid (or STEP) and re-importing it into a single part studio would be another way to allow you to scale the whole thing.
You can make a new part studio in context of the assembly. Then Transform - "copy in place" all the bodies. Finally scale all of these as you need. E.g.
Great information guys, now this leads to another question.
What mathmatical number in the Onshapes transform to scale area do I need to use to go from 1:1 to 1:87?
I had to tweek a cube in a test to find that I needed to plug in 0.08333333 to get the part to scale to HO size (1:87). Am I missing something here, or is there an easier way?
Here is a link to a document I have used to try and figure out how to change scale from one size to another.
https://cad.onshape.com/documents/d37ce4bb9fc9f4bacb10f959/w/564886a4fb7e3b55ae96c50d/e/1d44ec8a12acf4d2dddd3f02?renderMode=0&uiState=6793d98310a14617771840a9
If you take a look at the ratios you will see that I had to plug in some extented number to get it to scale to the right size. This doesn't seem right. There should be an easier way to preform this task.
Appreciate your insight guys. Thank you.
1/87 should get you to HO scale. 0.0833333 is 1/12, so you must have some inch/foot confusion somewhere. Your workspace units are inches.
I'm not sure what you mean by confusion. In the document I made a 6' square cube and tried making all the conversions from and to different scales and size. I am just having a hard time with the process making any sence math wise. I'm having to plug in up to 8 decimal places to just get the numbers to round out even. Is there a fix to that?
You can enter the scales as fractions. There's no need enter 8 decimal places. You can also enter "6 feet" as exactly that, and not manually do the math to get "72 in" an inch document. You shouldn't need to use 1/12 or 12/1 anywhere if it's just to sort out inches and feet. You can just set the measurements to the right units or if you want to keep the document units in inches you can enter measurements in feet.
You've labeled your transform/scale features very oddly. Your HO feature had 0.0833333 which is 1/12, not 1/87. You have another which is named 1:1 to 1:26, with a scale of 0.26. 0.26 is ~1:4. I'm really confused what you're trying to do.
Jack you can just type in "1/87" (or whatever you need) in the scale input field…and don't need to worry about decimals:
That might make it more intuitive.
I am scaling from a multible part model that is .26 and want to scale it to HO 1/87th. So if I just plug in 1/87 won't that scale the model at 1/87th of .26? That's to small for my needs if that is what happens. So the conversion is from one scale to another. Hope that makes better since.
What is 0.26? A measurement? A scale? Looking at wikipedia on model train scales I see nothing that's related to 0.26 or 1:26. I'm lost.
It's the size the model was built to fit a particuler space, it's not a scale used by model railroads. I'm trying to scale it so that it is a reccognized scale, HO or 1/87.
For the ratio math, you need to start with what you have now, and what you want to end up with, plug these values in, and you should be good to go. Forget about train scale - that only applies to starting with a full scale train , right?. I would use rail gauge as the "measurable" constant on any model you have, and use these numbers to figure ratio.