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lesterfoster
11-30-2004, 07:07 AM
Scaling,

Hi all

I have a model that I have made that is going to be sent out for 3D printing. It is made to scale in lightwave. A 2.5 inch part, I made it to 2.5 inches in lightwave. The part is 8 inches tall. How ever. After exporting it as a *.DXF, so that it can be imported in to AutoCAD to have the mesuments checked before sending it out for 3D printing, I found out the it is really the size of a peanut. It is only a quarter of a inch tall.

This is the first of what I hope, more parts like this that I want to make with lightwave. But if I cant make it to proper scale, than I am afraid that it is going to be my last. The reason that I have chosen to do it in lightwave is because, for one, I know how to use lightwave, and for two, Lightwave is better than AutoCAD at making organic shaped objects.

I was playing with lightwave's settings all last night, as will as searching the internet to fined out how I can make this proper. But I could not figure it out on my own as well, I could not fined the answers that I was looking for on the internet.

I am hoping that some one out there has used lightwave for sending out for 3D printing, and what did they do to get the size proper.

lunarcamel
11-30-2004, 07:11 AM
Anything I have ever had printed was saved in .STL format (stereo lithography) and that saved the measurements just fine.

Just my experience :)

lesterfoster
11-30-2004, 07:16 AM
How did you export it as a .STL format from lightwave. This is a aircraft part and I am using it to make a new tool to make these parts out of steel.

lesterfoster
11-30-2004, 07:27 AM
Anything I have ever had printed was saved in .STL format (stereo lithography) and that saved the measurements just fine.

Just my experience :)


Did you mean as a still image? I am trying to do 3D printing.

http://www.3darttopart.com/images/index_raptor.jpg
http://www.3darttopart.com/images/index_ninja.jpg
http://www.3darttopart.com/images/index_rustboy.jpg

3D art to part (http://www.3darttopart.com/index.php)

noiseboy
11-30-2004, 08:39 AM
How did you export it as a .STL format from lightwave.

Try Sean Hyde-Moyer's stl scripts http://www.chromecow.com

lunarcamel
11-30-2004, 08:54 AM
Most places I have done 3D printing prefer the STL format - I used an in house converter though. (I had hundreds of parts to print for stop motion mouth replacements)

I heard the exporter mentioned on chromecows site work great too - so I'd give that a try. If you are using 3D Art to Part it seems that they accept LW files - so I'd just give them a call to double check on measurements and you might not need to do anything extra at all.

liquidpope
11-30-2004, 09:17 PM
I think your real problem isn't scale.
Lightwave is metric, and Acad is english. Without adjusting for that difference, a model that's 8" tall in LW will be .2032" tall in Acad. About a quarter of an inch.

I do a lot of "Acad into Lightwave" conversion, and to keep true scale you have to import at a scale factor of .0254. (That number is 1 inch divided by the number of inches in a meter. Roughly 1 divided by 39.37. (my calculator only shows 10 characters, so as close as I can get is 39.37007874...))
So you're going the other way. Scale your Lightwave model up by 39.37, then export to Acad. No sweat.

Acad into Lightwave - scale down by .0254
Lightwave into Acad - scale up by 39.37

lesterfoster
01-25-2005, 06:48 PM
I must thank every one for helping me. This is my first 3D Art to Part model. It is a Piper PA-210 aircraft part. I am going to make it into a stamping tool to make these parts for real. Out of steel.

lesterfoster
02-06-2005, 09:36 AM
Hi everyone.

One of my first posts was about how to make a stamping tool with LightWAVE. And after three years and three hundred postings; I am finely making a stamping tool with LightWAVE..

3-D scanners, 3-D printers, lightwave, moldmaking. (http://vbulletin.newtek.com/showthread.php?t=24631&highlight=Finely+movie6.gif+file) :)

I started with the AutoCAD drawings, and had to make a mold with LightWAVE. The first thing that I did was import the AutoCAD drawings into CorelDRAW to convert it to a *.ai file, so I could import that into modeler, as modeler cannot import a AutoCAD file The first thing that I did was to setup my background to trace. Than after that I made a 3 inch disk on layer 2. But where was the disk? It was very very small. So I scaled the AutoCAD drawings to fit LightWAVE and I made the model according to LightWAVE.

But after drawing the model that is only 8 inches tall, I found after saving as a AutoCAD file that it only was of a inch tall. The size of a peanut..

So after that. I started over, and imported the *.ai file into modeler again, but this time I did not scale the AutoCAD drawings, or the *.ai file. And made the model that way. After saving as a autocad file and opining it in AutoCAD, I found that it was still to small. But not as small as trying to make it to LightWAVE scale. It was only 20% smaller than what it should have been.

I had to find a solution to this. I started looking for a anser. I looked in layout, and I noticed that it could import a AutoCAD drawing. So I imported it into layout and saved it as a LightWAVE model object from layout. I imported it into modeler and did not scale it at all. This time, instead of redoing the model in LightWAVE. I just made a disk to fit the 3 inch disk from AutoCAD. I saved that disk that I made with modeler to AutoCAD format. I opened that file in AutoCAD and checked its dimensions. To my surprise, it was the right size.

So I reset up my AutoCAD drawing in lightwaves modeler to make the model again. After finishing the model, I saved it as a AutoCAD file from modeler. I opened the model up in AutoCAD. And guess what. It was the right size

Now that I had it the right size, without scaling. It was time to prep the model for 3D printing. I deleted the end caps, and used the smooth shift command in LightWAVE to make the inside walls to what looked like 1/8 of a inch, and we sent it out to 3D Art to Part for printing.. They printed it with out scaling.

After about a week, we got the aircraft part from 3D art to part. It was almost perfect. It was only a little to thick in the neck area. So I fixed the neck area, and started to make the stamping tooling with LightWAVE.

As this report is quite long. I am going to half to divide it up in to parts. So keep checking this thread for my next update, where I am going to go into more detail an how I used LightWAVE to make this aircraft part the right size, and what I think that NewTEK can do to fix LightWAVE. As well, I am going to upload some source files for all to check out.

To sum things up. This 8 inch model, ended up being over 25 feet tall in LightWAVE. The 3 inch disk that I have been talking about. Ended up being over 10 feet wide in LightWAVE. And the 1/8th of a inch walls for the test printout, ended up being over 3 inches thick in LightWAVE.. Keep in mine, I made this aircraft part, without scaling in LightWAVE. But the original source files, or my working files, came from AutoCAD,

UnCommonGrafx
02-06-2005, 10:25 AM
I bet Deuce is watching this one...
:p

Fascinating topic and use of LW. Fabrication really does make sense. Waiting for more, Lester. Thanks for sharing it with the community, too.

Why didn't you send Art to Part a LW file? Just curious.

Gordon
02-10-2005, 05:46 PM
Hi Lester;
Good to hear that you got something of a 3D print working. Do you know what caused the 'necks' of the muffler to be too thick? Was it a modeling error or a conversion error?

Have you tried AccuTrans 3D convertor to go from AutoCAD to LWO? The full version is available from:

http://www.micromouse.ca/

The name (AccuTrans) seems to suggest that it will do an 'Accurate Translation' from one objet to another. The program has been developed by a person in Regina and he just posted an update not too long ago. The cost is only $25 CAD after the 30 day trial period has ended.

Matt
02-10-2005, 05:52 PM
Probably get shot for saying this, but, why use LightWave for something that should really be done in a proper engineering package? LightWave just isn't meant to used in this way - hence its lack of tools for such an application.

I'm not saying LightWave can't be used for this type of work, just that there are more suitable packages out there.

mattclary
02-11-2005, 05:13 AM
I agree with Matt.

Gordon
02-11-2005, 09:25 AM
Doing this project in LightWave is not without it's merits. Although not the best tool for the job (SolidWorks comes to mind) there are many other reasons.

1. By using LightWave you learn the program. Strengths and weaknesses and become more proficient. Knowing LightWave can lead to other opportunities for employment. For Lester this may be very important. OTOH, learning SolidWorks and becoming proficeint would not open up as many job opportunities nor be as much fun. I know I would rather be proficient in a tool that can be used to make a "Jimmy Neutron" or SciFi movie than one that is associated with making mechanical parts.

2. This was and remains, a proof of concept exercise. Lester already has LightWave so there is no need to spend the big $$$ on other software just yet. Once the concept of 3D modeling to 3D printing to casting is proven and the company is willing to pay for new software then it would be time to consider getting the best tool(s) for the job.

3. It took a lot of persuading and personal time on Lester's part to even get the company to try this. It would not have even been considered if the company had to 'contract' it out and/or buy more software. In fact, at first the idea was shot down and thought to be a dumb idea. Besides, contracting it out to someone else wouldn't have done Lester any good. :eek:

4. LightWave should have been able to handle this efficiently and accurately. If there is a solution to the scaling problem for moving the object between the two programs then it is feasible that LightWave could be part of the pipeline for this type of job. That would be a good thing for all of us as the more diverse markets there are for LightWave, the more money is generated which can go to more development.
This would affect not only the mechanical parts 3D modeling and rendering but also benefit architectural work. Just because LW may have some shortcomings in one area, is not a reason to roll over and play dead and suggest that another, better tool needs to be used. Instead, let's work on solving the problem and making the software even better. :)

liquidpope
02-11-2005, 02:54 PM
4. LightWave should have been able to handle this efficiently and accurately. If there is a solution to the scaling problem for moving the object between the two programs then it is feasible that LightWave could be part of the pipeline for this type of job.

As my other post failed to accurately state in regard to the scaling issue, there isn't a scaling issue. I shouldn't have used the word "scale" at all, and here's why.
ACAD's native unit of measure is undefined. Generally, we assign a default of "inches" per drawing, or per project. ACAD UNIT = 1 INCH.
Lightwave's native unit of measure is the meter. LW UNIT = 1 METER.
When transfering models back and forth, this must be taken into consideration, because meters are quite larger than inches. (I believe this falls into the "duh!" category of seemingly useless information, but it is somehow repeatedly ignored.)
Not a scaling problem, just a difference between native units per app.

I definitely would have used both cad and lw to generate that particular model.

Gordon
02-12-2005, 08:17 AM
Thanks Liquidpope;
I remember your explanation about the default units of measure between the two and this makes perfect sense. Scaling is NOT the problem but can be the way to work around the issue. As you mentioned just multiply everything in LW by 39.370787 and it will be accurate in ACad.

To sum things up. This 8 inch model, ended up being over 25 feet tall in LightWAVE. The 3 inch disk that I have been talking about. Ended up being over 10 feet wide in LightWAVE. And the 1/8th of a inch walls for the test printout, ended up being over 3 inches thick in LightWAVE.
1 inch in ACad = 39.3700787 inches in LW

therefore
8 inches in ACad = 26 feet 3 inches in LW
3 inches in ACad = 9 feet 10 inches in LW
1/8 inch in ACad = 5 inches in LW

lesterfoster
02-13-2005, 12:34 AM
Oh wow. All you people are just to good to me. I am speechless. The only thing that I can say, is thank you all for all the help over the past 2 or 3 years. It all comes down to this aircraft model and my next aircraft part for me, It is like I don’t know where to start.

I could start by quoting every one and responding to all questions. How ever I just want to thank every one for helping me and talk about how I made this aircraft part model the right size..

After making this model about eight times now, I have learned a lot about size in lightwave and autocad. I want to share some of my test resoults and methods with everyone. After descovering that if I imported the autocad drawing into lightwave and than saving my work to the size of the autocad file, without scaling, that it is the right size after transferring back to autocat.

Now, this model may have worked ok this time. It is unacceptable to my boss that I could not tell him just how big it was. At that time I could only tell him that it was either of a inch tall, or it was over 25 feet tall. I had to find a way of making these models, not just the right size with out scaling, but I needed to know just how big they are as I am making them...

On one hand I could not just do it in lightwave in inches just to scale up to fit autocad as you get floating point errors. In other words. The computer just can’t scale a object from 8 inches tall in lightwave and make it over 25 feet tall to work with autocad, without some distortion. And that is what I had after trying to do the scaling method. My model was out of proportion trying to do it this way.

The other way of importing background files from autocad without scaling into lightwave for 3D tracing, did work, how ever I had no idea on just how big it was. But this did put me on the right track on how to use lightwave with other cad like programs.

There are 2 scaling unit standards in lightwave. One is the base unit in lightwave is one meter. And all other units in lightwave work off of this meter. In other words, 39.37 inches is the same as 1 meter in lightwave. Just as it is in real life.

Now, in cad programs. A unit is what ever you want it to be. One unit in autocad, could be one inch, or one foot, or one meter or even one kilometer. A unit in autocad is what ever you need it to be. But a unit is still a unit no matter what you call it. The units do not change. Just what you choose to call it.

So after thinking about this for some time. I thought that if one meter in lightwave was one unit. Than I should be able to switch lightwave to meters, and it should be compatible with autocad without scaling. So I changed my units from inches in lightwave to meters in lightwave. And guess what I found. My model was 8 meters tall. Not 25 feet tall, the disk at the base of my model was 3 meters wide. Not 10 feet wide. And the wall thickness was 1/8 of a meter thick, and not 5 inches thick, like in lightwave.

Now I knew from all of my testing, that this model was 8 inches, the right size in autocad. And not 25 feet tall. Now in lightwave, with my new setting as meters. My model was 8 meters tall, or a better way of looking at it, Is it was 8 units tall. Every thing worked out. Now I could tell my boss that the model “is” 8 units tall, with a base of 3 units wide and the walls are 0.125 units thick.

To sum things up. If you want to make something in lightwave for animations, than all you need to do is use lightwave just the way that it is. But if you want to make something in lightwave that is compatible with autocad and other cad like programs “without scaling“. Than use meters in lightwave, as meters in lightwave are the same as units in autocad. All that you need to do is think of that meter or unit in lightwave as inches or centermeters or what ever you are using in your cad package. And lightwave is compatible with autocad without the need for scaling and the risk of having to deal with floating point errors .

All that I want NewTek to do to fix this, is just document this for others to benefit from.

Thanks for reading this.


________________________________________________
Some extra tips on 3d printing.

1) Don’t use lots of surface in lightwave. The 3D printers look at surfaces name the same as layers. Use part name in lightwave instead of surface names if you need to name things. If you do use surface names, the 3D printer will chop up your models and the 3d printers or you are going to half to fix it.

2) Use meters in lightwave, and think of it as inches. Or what ever units that you want it to be. Just tell the 3d printers what units you want it to be.

3) All of your objects have to be closed objects. There can not be any holes in your model. Things like eye sockets have to be patched some how.

______________________________________________
http://www.acornwelding.com/new/images/NewUPLOAD.zip


Here is a sample file of my stamping tool that I made with lightwave.
http://www.acornwelding.com/new/images/NewUPLOAD.zip

Gordon
02-14-2005, 12:25 PM
Hi Lester;

All that you need to do is think of that meter or unit in lightwave as inches or centermeters or what ever you are using in your cad package. I'm glad that you've managed to work around it. Eliminating the scaling up in size by 3937.007874% before saving the object - should save some time.


I could not just do it in lightwave in inches just to scale up to fit autocad as you get floating point errors. I'm not quite getting this. Using 'Modify-Size' and using the numeric requester to scale it up by 3937.007874% should be accurate to within one millionth of one inch. Where are you having the problems in floating point errors?

lesterfoster
03-19-2005, 05:05 PM
I have been thinking about how to reply to everyone comments and suggestions for quite some time now. I have been trying to do it without quoting everyone. But as I am not a creative wrighter, I fined it hart to reply. So I am just going to quote some of you.


Anything I have ever had printed was saved in .STL format (stereo lithography) and that saved the measurements just fine.

Just my experience :)

At first, I thought that you were talking about a STILL PHOTO or Render from lightwave. But now I understand that what you were talking about was a 3D file format, that is new to me. Thanks for the small but important tip.
________________________________________


Try Sean Hyde-Moyer's stl scripts http://www.chromecow.com
Thanks. I have downloaded it, but have not checked it out yet. On the other hand. I have been looking for the person who made a homemade laser 3D scanner for quite some time now. I Finlay found it at that link that you provided for me.

http://chromecow.com/mig/albums/3D_Scanner/06_Painter_Detail.jpg

________________________________________

If you are using 3D Art to Part it seems that they accept LW files - so I'd just give them a call to double check on measurements and you might not need to do anything extra at all.

Yes. You are right. 3D art to part was able to print it just fine. Even thoewI I had errors in my mesh. They were able to fix them for me with no extra charge..
________________________________________



Acad into Lightwave - scale down by .0254
Lightwave into Acad - scale up by 39.37

The lightwave into autocat setting worked, more or less just fine.
But the autocad to lightwave settings did not work too good. But thanks for the help anyway.


=UnCommonGrafx]I bet Deuce is watching this one...
:p

Thanks! I hope that the Deuce is watching. I think that this may help other lightwave users out there in the use for other things, other then just using lightwave for making movies.


______________________________________

Hi Lester;
Good to hear that you got something of a 3D print working. Do you know what caused the 'necks' of the muffler to be too thick? Was it a modeling error or a conversion error?

It was a modeling error on my part. All that I did, was add a spline disk in the neck area, and re-skin the object to fix this problem.
______________________________________


I'm not saying LightWave can't be used for this type of work, just that there are more suitable packages out there.

What programs would you suggest? We are looking at a 3D portable measuring arm (http://www.axila.com/) like this one. We are also looking at a new 3D package that can do organic modeling. We are thinking of RhinoCeros, NURBS modeling for windows (http://www.rhino3d.com/). What do you think of this program, or another one that would work with a measuring arm.

_______________________________

For simple things of this nature I have found lightwave a good tool. I am not using it to make real airplane plans or a big building. I am just trying to make one simple stamping tool with it. And I think that lightwave can do this. Not only that, but I think that it can do this faster and better than some cad package that is not strong at making organic shaped objects

I have made lots of these stamping tools, with my hands, and I feel that if I could do this with the computer and some kine of 3D modeling software. I could not only make them faster. But It would eliminate shrinkage of the materials and the casting prosses..
______________________________________

(I believe this falls into the "duh!" category of seemingly useless information, but it is somehow repeatedly ignored.)
Not a scaling problem, just a difference between native units per app.

I definitely would have used both cad and lw to generate that particular model.

I agree!! What do you think that newtek can do about this. I would like to see a demo video, explaining this, as well as a conversion chart in the manual explaining this. I think that if people had this explained to them. They would be able to use lightwave more like a cad like modeling program, rather than just a visual arts program
________________________________________


I'm not quite getting this. Using 'Modify-Size' and using the numeric requester to scale it up by 3937.007874% should be accurate to within one millionth of one inch. Where are you having the problems in floating point errors?

This is a good example of point errors. The number that you are talking about is 39.37007874%. Not 3937.007874%..!.. If I was to scale it up by this figure, It would have ended up being the size of the moon.

I wish that you were the accountant at work. This reminds me of the time that I got a rase from $9.00 an HR to $10.00 an HR. But the accountants at that time misplaced the dismo. I ended up getting a pay roll back to just $1.00 an HR. I am hoping that whin I get a rase to $20.00, that you can be the accountant so that you can pay me $2000.00 an HR.

And to anser your question about floating point errors. Odd numbers just don’t add up. Regardless on how small that fraction of that number is.

Thanks every one for your help

------------------------------------------------------------
_______________________________________

Below, you can see my big update. I got this from 3D Art to Part ,just yesterday. And it is the right size. Thank God. The next step is to send it to the brass people so that they can make it into brass. If it survives the casting process, than we are going to send in the rest of the stamping tool parts to 3D Art to Part.

Karmacop
03-19-2005, 08:22 PM
That is awsome. I hope it all turns out alright.

lesterfoster
03-20-2005, 09:06 AM
This is my next project. And it took me just a fraction of the time to make this tool as it took me to make the last one. The only problem with this one, is it’s size. Not the scale. But it’s size. It is almost 20 inches by 20 inches.

It is to big to print, using 3D Art to Part. So we are looking for other printers with bigger equipment that we can send our files to. As well as other printing methods, such as 3D CNC Milling.

We have found www.3drapidprototyping.com who is able to print something of this size, But they want too much money. Has anyone got some suggestions on who we can send the file to for 3D printing or 3D milling? I am afraid that if we cant find a method of printing, that I am going to half to go back to making these tools by hand, rather than using lightwave to make them.

Thanks in advance

Karmacop
03-20-2005, 03:25 PM
could you split the model in two, and get those two parts printed, and then stick them together after?

lesterfoster
03-21-2005, 06:04 AM
Yes! You guest it. That is what I did for my last 3D print. I just used the clone tool in a paint program to hide the seem. But with my next model. I would half to split each part of the model into 9 blocks so that 3D Art to Part can print it.

Now with most of these tools. You need 4 half’s to make one set of tool. So that means that I would have to have 36 blocks printed that would have to be reassembled back into the 4 parts that I am looking for. This is getting back to it being easier, faster and cheaper to just make it with my hands. This is why I need to fined someone who can print or mill these bigger models. The biggest one that I have made so far with my hands is 3.5 feet by 4 feet by 1.75 feet thick.

P.S. I found this good video explaining how 3D Milling works. I liked the video, so I’m passing this on for everyone to enjoy. :)

Freeman Manufacturing & Supply (http://www.freemansupply.com/video/preparing/machiningqt300.htm)

Karmacop
03-21-2005, 06:57 AM
Very cool. I saw one of these machining umm .. machines at a CG thing last year. with their examples you could easily see where the drill had been just like in the video, but they didn't show any examples of a "finished" product after using smaller drill bits. It's actually made me interested in them after seeing that video.

Gordon
03-21-2005, 11:56 AM
This is a good example of point errors. The number that you are talking about is 39.37007874%. Not 3937.007874%..!.. If I was to scale it up by this figure, It would have ended up being the size of the moon.

I should have used the word "Size" instead of "Scale"; sorry for the confusion.

Method A - Size by a Percentage
I created an box in LightWave 8" x 3" x 1/8" (.125") and Sized it by 3937.007874% (which rounds off to 3937.0079% (percent sign at the end of the number is very important) using the 'Size' tool and numeric requester and the end result was a box that was:
26 feet and 2.96 inches by 9 feet and 10.11 inches by 4.922 inches

Method B - Scale by a Factor
I use the same 8" x 3" x 1/8" (.125") box and Scaled it by 39.37007874 (which rounds off to 39.3701) (Note that there is NO percent sign at the end of the number) using the 'Center Scale' tool and numeric requester and the end result (after moving the lower left corner to position 0-0-0, was a box that was:
26 feet and 2.96 inches by 9 feet and 10.11 inches by 4.922 inches

So if you Scale it by 3937.007874 (no percentage sign) you would end up with a very large object. What I meant to say was to Size it by 3937.007874%

Either method (Size by percentage or Scale by a Factor), gets you the exact same object size.