Scaled VW file to PrusaSlicer

[AdamParboosingh]

Hello there.

Just recently bought a Prusa i3 MK3S+ to start printing scaled models as a theatre designer.  We normally build models in 1/4" or 1/2" scale.  I personally start building models in these scales in VW.  

 

When I export to PrusaSlicer using a .STL file, a warning comes up saying the object is too large for the bed.  So I'm needing to scale down the model in Slicer either through the Scale Factors or more precisely Size.  This makes me have to either do math or bring a scale ruler and a regular regular together to figure out exact size of the overall object.

 

I've even experimented with a simple 4' cube (in scale) and Slicer still gives me that warning.

 

How can I send a scaled VW model to Slicer without needing to possibly screw up my intended printed scale?  

 

And yes, it needs to be precise.  That's why we have computers do things for us.

 

Thanks.

Adam

[VIRTUALENVIRONS]

I believe PussaSlicer is a European company.  Switching your units to metric might solve the problem.  It may convert 1 inch to 1000 mm or something like that.

 

 

[Jeff Prince]

@AdamParboosingh when you built your vectorworks model is the geometry 1 to 1?  I’m not concerned about the scale you display it in vectorworks, rather what the actual size of things are in vectorworks.  If it is 1to1 as is the typical convention, then you need to scale it down before you make your STL file and make sure it will fit within your build envelope.  Once you import the STL into your slicer program, you should be good to go.

 

If your scaled model is still to big for your build envelope, then you need to break your model up into logical parts that will fit and easily be reassembled by hand.

 

keep in mind, fine detail might not print if it is too small for the nozzle you are using.  Sometimes you have to boost the size of some objects prior to making your STL, or delete them to get the final results you want.

[D-Dubs]

So you don't affected the printed scale you may want to copy and paste the model into a blank document first.

Then try Modify > Scale Objects... and scale the model down before exporting to exporting to .stl

You can do this in your current document rather than a blank document just make sure you Undo after you export the file. I hope this helps. 

 

[AdamParboosingh]

Thanks all.  

 

If I'm reading the replies correctly, this still requires me to scale the object down on my own.  Either through scale object in Vectorworks or through the Slicer object manipulation window, this makes me need to figure out the height of the scaled object in reality or proportionally change the size in the Slicer.  

[VIRTUALENVIRONS]

Is your first issue solved?  (too large for Bed).  It would be easier to answer you second question if you have the input units correct.

 

[Kevin McAllister]

13 hours ago, AdamParboosingh said:

Thanks all.  

 

If I'm reading the replies correctly, this still requires me to scale the object down on my own.  Either through scale object in Vectorworks or through the Slicer object manipulation window, this makes me need to figure out the height of the scaled object in reality or proportionally change the size in the Slicer.  

 

Yes, likely. Years ago I wish-listed a way to output scaled objects to STL but that wish was never implemented. If you don't want to do math, then create a sheet layer viewport in the scale you want to print at and then dimension the object to the extent of its bounds on the sheet layer itself. This will give you a size dimension to input into your slicer to print at the correct size. I check print size this way all the time.

 

Kevin

 

 

[AdamParboosingh]

Thanks everyone for your input.  Will be doing some more test prints this week.

[BartHays]

I guess the first thing to know is that STL files don't carry a measurement system. 

If you make a 4 foot cube in VW it will get exported a 48 "units"  - I am assuming your VW file is set to Inch/foot units based on your use of 1/4" and 1/2" scales

When you import into the Prussa slicer it assigns a unit, typically MM, but I see you have the "inches" box checked, so it is doing some automatic scaling.

 

You say you are modelling at either 1/4" (1:48) or 1/2" (1:24)" scale. I assume you mean you have your VW design layers set to one of those scales. 

VW layers can be set up at different scale, but this does nothing to the STL file - this only matters inside VW. 

(create a 4 foot cube on a 1:1 layer and a 1:48 layer, they both export as 48 generic units in the STL file)

 

Either that or you are manually calculating your sizes (a 3/4" - 4' x 8' piece of plywood would be drawn at 1" x 2" and .0156" thick) - I doubt you are doing that. 

 

So, I *think* the simple solution is that you just have to know the scale factor to punch into the Prussa Object Manipulation box

If it is smart enough to do the generic unit to inch conversion behind the scenes then use the your modelling scale factors:

 

1/4":1'-0" = 1/48 = 0.02083

1/2":1'-0" = 1/24 = 0.04167

 

Write these numbers down and tape them to your monitor 😉

 

 

The only caveat is if Prussa shows the scale factor as something other than 1 when it converts its default mm to inches, In which case you have to enter the factor for both the scale conversion AND the Metric conversion

 

1/4":1'-0" = 1:48 = 0.02083 > mm to Inches (=0.0393701) = 0.00082

1/2":1'-0" = 1:24 = 0.04167 > mm to Inches (=0.0393701) = 0.00164

 

Bart

 

 

 

[Kevin McAllister]

FYI this is the scale multiplier chart I shared with Adam in our message exchange..... I usually scale the object before exporting to STL and then undo.

KM