real world scale for laser cutting

[tomwyn]

Hi all,

I'm creating a simple 3D model to be laser printed & rebuilt with various materials. However I need to export my .obj to a very specific scale tolerance.

Does anyone have any tips about measuring real-world scale in houdini?

Obviously there is the measure sop, but I know the scaling in Houdini is mainly for DOPs, and that the units can be taken to mean anything from mm > Km, so am struggling to judge the actual scale this things will have in reality.

I've searched & found the following threads/otl which is of some use, but as I mentioned, if I measure 7.5 units, I don't know what those units represent.

http://www.sidefx.com/index.php?option=com_forum&Itemid=172&page=viewtopic&p=106028&highlight=&sid=99b43f820babf1fa2cac5a5127b39e84

http://www.sidefx.com/index.php?option=com_forum&Itemid=172&page=viewtopic&p=105594&highlight=#105594

http://www.sidefx.com/index.php?option=com_mailarchive&Itemid=212&view=WEB&msgid=50F3B60E.9030004@br1.org&perpage=20&revdate=off

Any tips or shared experiences would be greatly appreciated!!

Thanks.

[lukeiamyourfather]

I have milled and 3D printed objects from Houdini and other 3D software. What matters is how the CAM software interprets the geometry because that's what will create the tool paths for the machine (mill, 3D printer, router, laser cutter, whatever). Generally speaking one unit in computer graphics is equal to one meter unless otherwise specified. You could make each unit whatever you want like inches or centimeters and just make sure the CAM software knows that information when importing the geometry (or relay that information to the person using the CAM software).

[tomwyn]

Thanks lukeiamyourfather,

I assumed that the operator of the CAM software would be prompted by some-kind of interpretation dialogue, as in Cinema 4D when importing geo it lets you choose mm/cm/M/ etc. I just wanted to make it as easy as possible from my end so that the workflow was relatively stress free.

I've modeled my stuff in Meter units as that's what I want the final structure to be, so I think I'll leave it as it is & see what the CAM operator thins.

Thanks for the heads-up, appreciate it!