Please can you take this one step further and add texture/decal baking for full colour 3D printing? I fell foul of this recently as barely use materials in Rhino.
I would like to see some good use of this commands
- Move UVN
- Drag modes
- Select points toolbar
- Select chain
- Organic Toolbar
- Soft move
- Match perspective + _DollyZoom
- Flow along surface + _Dir issues.
- Edge tools
JoaquĂn
Thanks Dave. Use the subscription for another worthy contributor. I have a subscription thru my work.
Dennis
Hi Dave,
What about Cage Editing? No one seems to ever talk about that and itâs hugely useful if you donât overdo it.
Also, what about an in depth look at the History Enabled Functions in Rhino? They can be a real time saver.
What about a real world use for âFlow Along Surfaceâ and âFlow Along Curveâ. I use the commands frequently to put complex patterns onto manufactured shapes for production (etching or CNC work). Imported artwork from Illustrator turned into a 3D patterned object.
What about âA beginners Guide to Grasshopperâ. I still havenât a clue about grasshopper. Although, this may be more appropriate for V6 since it will be shipping with Grasshopper.
Ryan
I like all of Ryanâs suggestions, especially the history functionality idea. An intro to Grasshopper would be great too - while youâre at it how about a Panelling Tools tutorial?
https://wiki.mcneel.com/rhino/faqtolerances
High tolerances are not needed because existing manufacturing methods cannot print the models with high accuracy. The machines can cut alloys with high accuracy, but they cannot print alloys with high accuracy. If you make mechanical parts that must fit perfectly (e.g. bearings or gears), you define these tolerances with written dimensions. A craftsmen will ignore your model and he will set his cutting machine to follow your written dimensions. Swedish firm Arcam makes electron beam machines which print variety of strong alloys with +/â 0.4 mm accuracy. Other printing machines have lower accuracy. Parts made of polymers are elastic, so 0.5% accuracy is generally enough to ensure that they fit. If you design all fitting parts, give them extra space - better to make the fit too loose than too tight. Typical mold shrinkage of polymers is 2% - the polymers shrink when they solidify.
The angular tolerance is important when you make molds for polymers because it may be difficult to remove the part from the mold having wrong draft angle. Rhino DraftAngleAnalysis command is necessary to check the molds.
If the parts do not have to fit, the only reason to exceed 0.2 mm tolerance is to reduce friction (aerodynamic drag or hydrodynamic drag). In other words, the surfaces must be smooth rather than accurate. Rhino EMap and Zebra commands are best to estimate smoothness. A seam between two surfaces looks smooth when the continuity between the surfaces is G2 (curvature continuity) or better (G3 or G4). G2 corresponds with degree 3 polynomials. Some experts claim that high quality NURBS surfaces have degrees of 5 or higher, but they cannot prove it. High degree surfaces slow down Rhino and use more memory (RAM). Many mechanical CAD programs cannot import surfaces that have higher degrees than 3.
The smoothness is very important when the parts are made of monolithic bulk metallic glass. When the parts come out the mold, they have perfect mirror finish - they look like things that have been polished. If your model of the mold is not smooth, its flaws will be easy to see.
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Thanks for all of the suggestions, but please keep in mind that these are intended to be 5- to 10-minute stand-alone demos. Grasshopper and paneling tools could easily require an hour or more.
If youâre a lynda subscriber, there is a NonDave â and excellent â course called Learning Grasshopper by Chris Reilly. I highly recommend it.
After setting up a 3dm file water tight. Saving it as an Stl file and cleaning up the mesh in preparation of three dimensional printing. Including reshaping the mesh eliminating the extremely small triangles.
Hi Dennis
That is very generous. Iâd still like to send this to you â if you could think of a friend / family / needy student / colleague to pass along.
If no one comes to mind, then no problem. Iâll find a home for it.
Dave
I tend to select a tolerance based on my needs ⌠and to avoid exploding fillets! The manufacturing or prototyping process is important, but my main concern is model accuracy.
Fortunately, the latest File â New templates, like âsmall parts / mm,â do a great job for 99% of my needs.
This is intriguing ⌠but, when prototyping, I focus a lot of attention on keeping my model super clean and closed. Then, when I create a NURBS-to-mesh conversion, itâs pretty much 100% clean and closed as well. The few times where my mesh has a problem appear, I do the following:
- delete mesh
- review NURBS for any problem areas / naked edges etc â fix as needed
- re-generate a mesh-to-NURBS conversion again OR with slightly different settings (tighter or looser)
- check the result ⌠and its usually OK
But, this process could make a great little demo.
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Youâre right, Dave. Apologies, I was thinking of your 60 minute project series you started a while ago. Most of my suggestions would indeed require more than 5 - 10 minutes.
I believe I did watch some of that course, Iâll take another look.
Speaking from experience I feel like understanding the concept of splitting an edge was a huge boost for modeling complex shapes for me. I always tried to fill in the gap with what I had available (edges of surrounding surfaces) and if it didnât work I attempted rebuilding everything so that I will have only 4 good edges leftâŚ
and that brings me to my other point
I think it would be a lot more helpful to explain how to model something rather than how to use a toolâŚFor example how to layout surfaces? Most people probably make surfaces with edge to edge approach and its easy if you are modeling something like table lamp but how would you layout surfaces if you are asked to model something like this https://ae01.alicdn.com/kf/HTB1Zn84KFXXXXaiXXXXq6xXFXXXp/Brush-cutter-Handheld-mini-DC-Power-electric-battery-cordless-small-grass-cutting-machine-cutter-saw-dc.jpg
I suppose you could make a body as one piece with very complex geometry but surely there is a better approach
How many users have had the experience of finding tiny little lines that prevent otherwise apparently continuous lines from joining, or tiny surfaces that keep polysurfaces from closing, etc. Maybe this has already been addressed by previous suggestions about tolerances, but I would like to see a video focused specifically on avoiding the annoying little âbitsâ that Rhino is prone to creating.
I have seen this from some of my students, but not in any of my files for a long time. Can you post some visual examples? This could be a very good demo IF we can duplicate this behavior / understand how it happens.
Hi Dave,
Sorry, I donât have any examples and donât know how to generate them, but will be on the lookout and will send you the file next time I find something appropriate. .Maybe someone else on the forum will be able to contribute.
Hereâs an example and a great response from Pascal - itâs so helpful:
I mostly use edge softening in Keyshot now rather than applying a fillet but the script helps find small details that often make commands fail. It also helps identify how to clean things up before using _ptUnrollFaces - unroll faces in panelling tools.
I saw someoneâs suggesting of using Make2D to create continuous curves where SelDup wonât help and of course, CurveBooleanâŚ
Andy
@Andrew_Nowicki @MisterB Hi Guys, I donât know if this is helpful, but these days higher printer resolutions arenât uncommon. I know of an additive metal deposition printer capable of printing in 50micron resolution (0,05mm or an 8x higher resolution then you stated). The same company offers strong and dimensionally stable polymer materials utilizing carbon fibre in their high resolution 3D printers. So High tolerances might still be needed.
Have a look if you like: https://markforged.com/metal-x/
And in general I would model with a tolerance at least 10x smaller than the precision required for the part. For example if you need 0.01mm tolerance machined parts, model with 0.001mm tolerance. if your 3D printer can hold 0.1mm, model with at least 0.01mm tolerance.
That way you will be sure that any errors in precision of the final part come from the manufacturing process itself, not the from your 3D computer model. Itâs always better to have a 3D model that is more precise than you need than one that is not precise enough.
âMitch
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@Helvetosaur, agreed. Thanks for your addition. 