Importing from Solidworks and some solutions to scaling issues

[Anonymous]

Hello CADsters! 

Hopefully I can be of some use to anyone who has the task of importing Solidworks models into AutoCAD. What follows are a series of steps and general notes I have accumulated during my attempts to accomplish this goal. I hope that this is not a "one off problem" and helps other users too. I would appreciate feedback; in case I must set up another person in my company to do the same thing. I apologize if I am long winded; but I would rather be thorough and concise in my process. Also I am running AutoCAD 2020 and Solidworks 16. Having said that, lets dive in.

Goal: Import part or assembly from Solidworks at the correct scale.

To start, type: IMPORT and select the desired Solidworks file. Let the program process. When the balloon in the lower right pops up, click the blue text and watch the model import. Here is where I ran into my first problem. The Assembly I am importing has a known dimension of 12" so I can reference it. The part was measuring at 0.3048". I know that when you import the model, you can select the geometry and look to the "Block Reference" properties window to change the scale right there in the: Scale X, Scale Y, Scale Z, under the Geometry tab. You can also see what the scale is; and in my case was: 0.0254 for X,Y,Z. If you multiply .0254 by 39.3701 (1 mm = 0.0393701 inch), you get 1.00000054, IE: 1"... SO I change all three scales from: 0.0254 to 1, and the part measures correctly. No clue as to why its scaled as such; seeing as the part in SW is set to inches and the drawing units in ACAD are as well. This is one work-around, but it involves a few extra steps and that kills efficiency over 2000+ parts and assemblies. I also stumbled across the "delete the part" and then "insert" it at the correct scale (still not fully understanding what the distinction of insert vs. import is; or why it changes); but that is another workaround.

After replying to another post on the forums, I started really digging into the INSUNITS, INSUNITSDEFSOURCE, & INSUNITSDEFTARGET commands. I eventually sketched a table out and started experimenting (I would Crtl+Z all the way back to "nothing left to undo" and close the drawing and start over if my result was undesirable; so the settings I was playing with wouldn't save). Knowing that when you change the INSUNITS value to 0 from 1, you define the drawings units as just a coordinate ("unitless"); I was able to start playing with the other variables. For my issue of scaling 1mm to 1", I changed the INSUNITSDEFSOURCE to [6] (meters), and the INSUNITSDEFTARGET to [1] (inches). I did this because the Block Properties menu has a section that defines the block unit as meter, and I just assumed this would be a good place to start. The next time I tried the IMPORT function, the model came in at the correct scale. ***NOTE*** You need to set the INSUNITS before you import anything. I have these settings saved in my .DWT files that I use as my base import, so I only have to do this once.

To reiterate, I do not know why the Solidworks file was importing at micro scale because I set the drawing units to IPS in SW myself. I don't have a lot of knowledge in the realm of SW, so that could be part of the problem. I am sure that when I need to insert a block from another source, I will need to use the "scale with base-point" if it comes in incorrect. OR adjust the INSUNITS command. 

Another thing I noticed, that I did not detail in the process, is the "-DWGUNITS" command. I don't know if it influenced the import or not... I thought it did; but when experimenting, I could import the correct scale when the "scale objects from other drawings upon insert?" & "Match INSUNITS to drawing units?" were set to yes, or no. To start the initial round of experiments I had both set to "no"; in case it does matter. 
OH! On the Solidworks side of things; the coordinate systems native X,Y,Z is different than ACAD. If you navigate to the front view (for example) the 'Y' is pointing "north", the 'X' is pointing "east" and the 'Z' is pointing at you. If you do the same in ACAD (front view); the 'Y' is pointing away from you, the 'X' is pointing "east" and the 'Z' is pointing "north". A simple "3DR" ought to set you right. That bit me in the butt after an oddly symmetrical part came in and I didn't notice.

Really when it comes down to it, I just needed to slow down and read and understand the commands at each point along the way. It is intuitive after you comprehend what you are doing. But for this guy; with time constraints and the request from management to "just do your magic!" on a timeline, its quite an intimidating process to undertake. Maybe this post can help as a guide; and maybe the admins can elaborate on steps; or explain the why's where I assume. Or point me out if I am wrong! I don't want to misinform if I can help it.

Okay, I think it's over. Thanks for reading!
Gabriel

[cadffm]

😂

Much work (to write it down), for this you get a Like from me.

Yes, it's hard to understand all these things for the first time.

(but it would be really good to attach a source-DWG from SW and the target DWG from if you like to discuss with some others)

It is impossible to write down the easy way for all, because others (also you, at the next time, next project) have

other settings, other templates

and then ??? Yes, the only thing what works perfectly is to know what is important and how it works.

Knowledge is the only key.

[Anonymous]

Haha, yeah it took me a little bit that's for darn sure. I am unable to attach a specific DWG or SW.part today; as I'm working on a DoD contract. I'll have to break away from actual work at some point to make an example file, and probably an example .DWT template too. I don't want to violate the NDA I signed; that would probably suck to deal with...

But yeah I didn't really consider the changes I have made from the bone stock ACAD up to this point; and I likely left out key parts of the process. I came into this role two months ago as a good 3D designer and modeler; so to be doing the setup and admin work with only the forums as help was a sweaty lil piggy. But hey, I can market myself as such now haha! A low level admin; not a sweaty lil piggy...

Thanks for the response and positive feedback; that makes the whole deal that much better. 

[lynx20]

Excellent explanation for the work around except for one issue.  Import a SLDASM file.  Yes, the main block comes in at a scale of 1.0 and measures correctly using imperial dimensions but all the ‘sub-blocks’ [the blocks within the main block] are at a scale of 0.0254.  Open the block in the block editor and every object is scaled down to 0.0254 [sub assembly blocks, polylines, circles, etc.].

Workaround: Explode the parent block and now all the sub blocks are magically transformed to scale 1.0.

Here is the real magic - all the circles, etc. are scaled up X25.4.  Example.  Before you explode the parent block, draw a circle with a diameter of 0.05” within the block.  Explode the block.  The circle is now Ø1.9685”.

Now recreate the original parent block and you now have a correctly scaled assembly.

But wait – all the blocks and objects within any of the sub blocks are still at scale 0.0254.  If Autodesk refused to acknowledge this a bug after all these months [or should I now say years] – that tells me they either don’t know what is going on or they don’t care about users who need to share between other programs.

[pendean]

@lynx20 Bug reporting to Autodesk is done here https://www.autodesk.com/company/contact-us/product-feedback then here https://knowledge.autodesk.com/customer-service/account-management/users-software/support-options#:~.... and every one of us has to do it: they may have a list or they may not, but they don't come to these forums looking for more issues.

Do your part. TIA.

[Ewan_D_Ball]

Thank you! I was having the same issue. I had just never scrolled down far enough in the properties pane to realize that the block units the solidworks part used was "meter" even though in solidworks I changed everything to millimeters. Changing the source units for incoming content to meters fixed it, and now it comes in at the right size scaled to 1.

Since I draw in acad then redraw in SW then bring it back to acad to make sure it's identically drawn (for various unchangeable reasons), I had to keep changing the scale to 1 over and over and over. I'm much obliged.