Jump to content
Hash, Inc. Forums
Sign in to follow this  
UNGLAUBLICHUSA

Need Help Exporting for Plastic Injection Molds

Recommended Posts

:angry: Hello and here is my scenario:

 

I have developed MANY detailed models in A.M., V15 - that I want to have plastic Injection Molds made from. The Models are to Exact Scale because threaded Inserts will be needed and holes will need to be lined up and they need to interact with other components in the "Industry Standard" size. I am trying to convert one of the many files with little success.

 

My Problems:

 

1. AM's MDL files are not supported except in Wings 3d (Old version).

2. When I export the model into a *.OBJ or *.DXF File - I lose my curved surfaces. I must have curved surfaces (I thought DXF supported that? No? How do Autocad users get their smooth models?).

3. I got help from someone very nice on the Forum with V16 to do an *.STL conversion....it has all hard edges as well.

4. No matter what way the file is exported, the model increases in virtual size from ~14" to 37 1/2" wide - Dude W.T.F. is A.M. doing that for? I need it to be exactly the same size I modeled it in.

 

Anyone want to touch this with a 10 foot pole? Thanks in advance,

Share this post


Link to post
Share on other sites
:angry: Hello and here is my scenario:

 

I have developed MANY detailed models in A.M., V15 - that I want to have plastic Injection Molds made from. The Models are to Exact Scale because threaded Inserts will be needed and holes will need to be lined up and they need to interact with other components in the "Industry Standard" size. I am trying to convert one of the many files with little success.

 

My Problems:

 

1. AM's MDL files are not supported except in Wings 3d (Old version).

2. When I export the model into a *.OBJ or *.DXF File - I lose my curved surfaces. I must have curved surfaces (I thought DXF supported that? No? How do Autocad users get their smooth models?).

3. I got help from someone very nice on the Forum with V16 to do an *.STL conversion....it has all hard edges as well.

4. No matter what way the file is exported, the model increases in virtual size from ~14" to 37 1/2" wide - Dude W.T.F. is A.M. doing that for? I need it to be exactly the same size I modeled it in.

 

Anyone want to touch this with a 10 foot pole? Thanks in advance,

 

All export-plugins will convert patches to polygones. There is no way to export to CAD-curves or something like that in A:M. (in fact I dont think that any 3d-programm can do that, so I am not sure).

If you want to 3d-print something out that is not too much of a problem so. STL, which is the file-format used by many 3d-printers although consists of polygones. The question is: How many do you export with? Use 16 polygones per patches and prepare your models to have more splines/patches than needed in A:M so you get a nicer surface in polygon-models. Another way is to export for example a ply-file, reimport it and export it again... like that you increase the resolution of the model and the amount of polygones.

 

See you

*Fuchur*

Share this post


Link to post
Share on other sites
:( So it looks like I will have to remodel everything in another program....after I buy it?

Share this post


Link to post
Share on other sites
:( So it looks like I will have to remodel everything in another program....after I buy it?

 

Try the PLY export and reimport to increase the subdivisions, then export to STL.

 

PLY is included in A:M

Share this post


Link to post
Share on other sites

It's GOT to have rounded edges in some places - some parts must be smooth and not faceted. I can probably import the DXF into Autocad if I buy it......

Share this post


Link to post
Share on other sites
It's GOT to have rounded edges in some places - some parts must be smooth and not faceted. I can probably import the DXF into Autocad if I buy it......

 

Doesnt matter where you import it... polygones are polygones... all you can get is something near to smooth edges, but polygones are always facets... in other programs you can smooth it optically (using a special shading-algorithm) but it still remains facetts... it is only a trick to get it otherwise...

 

Keep in mind that 3d-printers, etc. can only print a certain resolution too... that means they will produce automaticall a layered object which will not be smooth anyway.

The more expensive the 3d printer, the higher the resolution, but somewhere it is over and you will have to use sandpaper to get it smoother anyway...

 

But lets begin from the start: What do you plan to do with the data?

 

See you

*Fuchur*

Share this post


Link to post
Share on other sites

I need data for a CNC Machine to cut Plastic Injection Die Molds out of metal. What comes out of the mold - needs to be sharp edged in some areas and smooth in others. Curves need to be smooooooooooooooth. STL - even in ABS wouldn't be a strong enough demonstration piece.

Share this post


Link to post
Share on other sites

Just curious.... What file formats does a CNC machine take?

Share this post


Link to post
Share on other sites

1 of them is the native Autocad Format. I would have to look up what software my possible sources use that may take other formats.

 

EDIT: Also - Solidworks, ProE, STEP, ParaSolid, ACIS, IGES.

Share this post


Link to post
Share on other sites

Depending on the complexity I might be able to convert the files to true cad files and provide a set of open nurbs for you from an obj file using Amapi Pro.

 

Steps I did from the test AM file I had is I exported out an obj at a tesselation of 16.

Imported the obj to Amapi Pro merging all points and duplicate uv's etc

Sub divided the obj using a doo sabian at a minimal smooth of 1

converted the sub d to a nurbs smooth.

 

If your doing tons of models for injection modeling you should be using another program other than a program that exports polygon based models. The closest thing to Amapi is T-splines for Rhino or Max but the investment is pretty big along with the learning curves.

 

Organic models that aren't dimensionally critical can be done in many programs and stl files are usually fine.

 

There might be other programs that can convert the objects the way I did that I'm not aware of.

AM_model.JPG

amapi_nurb_conversion.JPG

Share this post


Link to post
Share on other sites

Never heard anything back on this, if you want you can post a mdl, I can try to convert it to nurbs for you and provide open nurbs file you can use. Specify the exact dimensions on the object and I can confirm if there is distortion or not. Exporting to size really doesn't matter since I would be converting units to real dimensions.

 

In AM I usually stick with cm which it seems happiest.

Share this post


Link to post
Share on other sites
No matter what way the file is exported, the model increases in virtual size from ~14" to 37 1/2" wide

This might have something to do with the fact that A:M does it's internal calculations in centimeters. 37.5 cm = 14.8 inches. So the model was just converted to centimeters when A:M exported it.

Share this post


Link to post
Share on other sites
This might have something to do with the fact that A:M does it's internal calculations in centimeters. 37.5 cm = 14.8 inches. So the model was just converted to centimeters when A:M exported it.

 

So A:M converts it to 37.5cm but doesn't convert it back into relative inches again when re-opened and just leaves the number at 37.5 even if the units selected are inches and not CM? Do you think changing the units to CM before he exports it would maintain the original scale? Ya know as it'd already be 37.5cm so no conversion of units would need to take place.

Share this post


Link to post
Share on other sites

I use cm's in AM becuase at one point there was an issue with one of the plug ins not supporting the other units. It really doesn't matter as long as proportions are correct.

 

If your making objects that are going to be made into real life objects then you should always check the model in an outside program and change the units if necessary.

Share this post


Link to post
Share on other sites

I am reducing the files in size in AM then exporting to DXF and using "Other" software for my usable files. That said, I think there is an inherent problem if the convert to DXF OR OBJ plug-In's on their own, increase the 'real size' of the model. The Translation is taking 37.5 CM and making it 37.5 Inches - that is just not right and should be addressed.

Share this post


Link to post
Share on other sites

Just for giggles I opened up one of the models you sent me to convert a while back, changed the units to CM and then exported it to .STL. Try opening it in your other software and see if it's still blowing up the model size.

 

STL_13_Inch_SNARE_Sub_Woofer_MASTER_Part_1__Drum_10_18_2011.zip

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

×
×
  • Create New...