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rwanttaja
02-10-2019, 10:47 AM
I found a Solidworks model of an aerospace vehicle from my past. I downloaded it, planning on making a small keepsake of my involvement in the program using my 3D printer.

One problems: The Solidworks model is full-scale. My printer can't handle a 15-foot wingspan, and I'd have trouble finding a spot for it on my desk.

I've been experimenting with altering the design table to produce a scaled version of the original part. Have had two issues come up.

First, after transferring the dimensions to the design table, the "save" icon on the Excel interface is grayed out. I can't apparently save the updated version. However, if I just click on the main drawing area, the design table is apparently accepted by the program. Is that's the way it's supposed to work?

Second, the scaled alternate configuration produces a bunch of errors. I seem to have traced it down to the fillets...they don't scale down with the design table (eg, tries to keep a 40 mm radius fillet on a model 100 mm in size). Any quick way to fix that? I'm going through and manually changing the radii, and it's a bit of a slog.

Ron Wanttaja

Dana
02-10-2019, 04:18 PM
Can Solidworks scale an dumb (imported) solid? If so you may be able to export and re-import it via STEP and scale the imported copy.

rwanttaja
02-10-2019, 07:45 PM
Can Solidworks scale an dumb (imported) solid? If so you may be able to export and re-import it via STEP and scale the imported copy.

I actually received the vehicle in several formats...one of which WOULD have printed if I'd set the printer scaling factor to 1%.

However, I do want to be able to edit the vehicle to reflect the difference in the mission I was associated with, and to optimize it for my particular 3D printer. And...I'm hoping to modify it to use as a stand for the challenge coin I received after mission completion.

I may end up just redrawing it from scratch; a good training exercise. The amusing thing is that all the features on the model I bought ($7) have German labels. Been pummeling the online German to English dictionaries to figure out what stuff like "Schnitt-Linear-Austragen-Dünn4" is....

Ron Wanttaja

cwilliamrose
02-10-2019, 08:07 PM
There's a SCALE function built into SWx. It's main purpose is to compensate for material shrinkage when designing tooling like molds, casting patterns, etc. You can scale a model equaling in all directions or choose different scales for each (X, Y, Z) direction. I believe it will work on dumb (imported) models or native SWx models.

rwanttaja
02-10-2019, 09:28 PM
There's a SCALE function built into SWx. It's main purpose is to compensate for material shrinkage when designing tooling like molds, casting patterns, etc. You can scale a model equaling in all directions or choose different scales for each (X, Y, Z) direction. I believe it will work on dumb (imported) models or native SWx models.

I tried the scaling function, but it's confusing. It shrinks the screen size of the model, but all the dimensions, apparently, stay the same.

I'll keep fiddling with it.

EDIT: OK, think I see my mistake. I needed to scale it around the origin. All the model dimensions are nominally unchanged, but a small feature drawn next to it is at the proper size. Thanks!

Ron Wanttaja

cwilliamrose
02-11-2019, 08:54 AM
I did this demo using a two body part and scaled one of the bodies around the Centriod which is the default. Any measurements taken of the scaled body are 1/10 of the pre-scale size. This function also works on imported (dumb) solids.

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rwanttaja
02-11-2019, 10:11 AM
I did this demo using a two body part and scaled one of the bodies around the Centriod which is the default. Any measurements taken of the scaled body are 1/10 of the pre-scale size. This function also works on imported (dumb) solids.
Thanks! Got it to work. Printed the file of that ~15-foot wingspan vehicle as a 1.5" model. Now I've got to edit a copy of the file to eliminate all the fine detail like panel lines, thruster nozzles, etc. that don't come out when it's scaled so small. Also fattening-up some items like the fins because they're too delicate when shrunk down to 1/100th-scale; the 3D printer can't handle them well. I've also had to alter the model to handle other limitations of the printer, and have learned a lot from that.

I'm still being thrown by the differences between SW and 2D drawing packages I've used. After running the "scale" function, I originally thought it didn't work since the dimensions of the design were all the same. Didn't notice that a "Scale" entry had been added to the end of the features list.

The Seattle area has been hammered by a rare series of heavy snowfalls, so Solidworks is getting pretty heavy use in my house.

Ron Wanttaja

cwilliamrose
02-11-2019, 11:02 AM
Yes, it scales the geometry of the body and doesn't change the dimensions used to create it. Your experiments in doing it that way show why that's not a good approach.

A little more snow and you'll be a SWx expert!

PaulDow
02-12-2019, 09:19 PM
... all the features on the model I bought ($7) have German labels. Been pummeling the online German to English dictionaries to figure out what stuff like "Schnitt-Linear-Austragen-Dünn4" is....
If you have an Android phone or tablet, install Google Translate. Sure, the big Alphabet company will know what you're doing, but you can point the camera at the text, and it will display translated on the screen.