# 3D cad



## abby (Apr 17, 2009)

I have noticed several posts related to 3D cad software and for beginners , like me , I can highly recommend 2D/3D Viacad by Punch software.
It is available for both Mac and PC , I use an IMac and it runs well, it can be downloaded for free trial and if you like it buy a license.
At 99.00 USD it is good value. There are several tutorials for down-load and a useful forum.
After only half of the first tutorial the average computer user should be able to build 3D models.
I believe that Turbo-cad uses the ViaCad engine , but I may be wrong.
This is the assembly drawing for a G1 loco that I am building, and to date has over 50 parts or assemblies.





so many that I have hidden some for clarity.




you will need plenty of memory for large assemblies , I have 2.5 Gig in my IMac.
The only problem that I have come across to date is that some fillets cannot be drawn , but this is quite a minor issue.
For a more realistic picture export your drawing as an OBJ.file and render.
I use Cheetah3D.




I have no doubt that building a 3D model before starting on the metal is well worth while and I have found several faults in the original drawings for this loco.
It also makes scaling down a breeze.


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## Kermit (Apr 17, 2009)

Thanks abby

I'll add that one to my 'research needed' list.

I've put in about 8 hours now with Googles sketch up. moving multi-lined assemblies is kinda slow and jerky(may be a memory issue). The more lines in the choosen area the harder it is to move it due to delayed reaction time. Selecting an entire complex object to move caused my work computer to stop responding. It is not a high performance PC by any means but is less than 1 year old.

When you reference memory I'm assuming you are refering to the need for more 'on board' memory chips?

Love your postings so far,
Kermit


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## Kermit (May 1, 2009)

Haven't had any luck getting answers to my questions so far, so without paying any attention that fact.
I'll ask another one.

For the users of Google sketch up...How do you make a 3D 'spring coil'?

I've managed to figure out how to make a 2D helix but I'm not having any luck with turning it 3D.


See attached view for the exact problem.

Kermit 

View attachment Closeup of steam chest.pdf


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## abby (May 1, 2009)

I didn't like Sketchup but drawing springs in ViaCad is amazingly easy , just select the helix tool , enter dimensions and draw the helix. next draw shape of spring section and position it on the helix , finally choose single path sweep tool and choose the section and the path (helix) bingo !


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## rickharris (May 1, 2009)

Kermit  said:
			
		

> Haven't had any luck getting answers to my questions so far, so without paying any attention that fact.
> I'll ask another one.
> 
> For the users of Google sketch up...How do you make a 3D 'spring coil'?
> ...



Form a path with the arc tool - this is best done by making a vertical line at the start/end the correct height for the pitch of the spring. Draw half a circle between the lines attaching to the relevenmt ends to produce a sloping curve.

Repeat this for a long as you need the spring - this takes less time than i took to type this!

Now form a circle perpendicular to the end of the path and use the follow path tool to make the circl;e follow the helix path. Once done it is fairy easy to do. The follow path tool is very powerful when you realise you can sweep any shape round a path.

Remember thar Sketch up is really intended for architecture rather than mechanical drawing.


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## Foozer (May 1, 2009)

Kermit  said:
			
		

> Haven't had any luck getting answers to my questions so far, so without paying any attention that fact.
> I'll ask another one.
> 
> For the users of Google sketch up...How do you make a 3D 'spring coil'?
> ...



Use the Helix Tool (might be a plug in item) to create the basic shape






Add to one end a circle of desired diameter






Use the follow me tool to grab the face of the circle and drag it to the end of the helix






POOF! one spring Hope it helps


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## Kermit (May 1, 2009)

Thanks Foozer, I hadn't though of using a plugin! :

I'm searching Google now for such a plug in but so far no luck.

I've got thousands of returns to look through,so, could be a day or two, ;D

I'll also give the helix a go again with more attention to how I use the follow path tool.


Thanks everyone,
Kermit


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## Foozer (May 1, 2009)

Kermit  said:
			
		

> Thanks Foozer, I hadn't though of using a plugin! :
> 
> I'm searching Google now for such a plug in but so far no luck.
> 
> ...



Ruby script helix12.rb whatever that means can find a bunch here especially the point.rb one.


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## sparky961 (May 1, 2009)

For what it's worth (about $0.02, I'd say..), Google's Sketchup is simply indispensable for quick mockups and ideas. The majority of things I've ended up committing to wood and metal have first been put together using this program.

I always seem to discover a few "gotchas" with my ideas, and committing them to a 3D digital design first has saved a lot of time and trouble for me.

Also, I rarely print out dimensioned plans anymore. I have the computer in my work area and I just walk over and take a virtual measurement wherever needed.

-Sparky


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## rickharris (May 2, 2009)

Foozer  said:
			
		

> Ruby script helix12.rb whatever that means can find a bunch here especially the point.rb one.



Ruby is a programming language that Sketchup can use to insert extra functionality (a plug in).

To insert the plugin right click - save link in - select the sketchup folder and then the plugin folder. It should download a .rb file into the plugin folder. The necessary menu will appear in the draw menu in drawhelix case.

Drawhelix13.rb works for me. Note you need to ungroup the helix from the edit menu to get followme tool to work.


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## Kermit (May 2, 2009)

rickharris  said:
			
		

> ... you need to ungroup the helix from the edit menu to get followme tool to work.



?? Is 'ungroup' another command to be found in the menus?

Or is it something that comes up(as from a right click on the mouse) ?


I'm real stupid till I get 'it',
Kermit


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## rickharris (May 2, 2009)

Kermit  said:
			
		

> ?? Is 'ungroup' another command to be found in the menus?
> 
> Or is it something that comes up(as from a right click on the mouse) ?
> 
> ...



Select the helix once drawn and than go to edit menu. At the bottom it will say something like group 1 - Click on this and several options will pop up. The ungroup command in sketchup is actually Explode.

After that you will be able to make the profile you draw follow the helix line. The profile you draw MUST be perpendicular to the end of the helix.

Note that you can produce positive and negative threads (external and internal) if you draw a suitable profile at the end and sweep it round, Deleting the inner edge will produce an open thread (almost a negative) for use in nuts etc. This is a qurk of the way sketch up works.


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## Kermit (May 2, 2009)

That clears it up. Thanks.

I've run into the quirk several times when doing intersecting through holes. I would lose the internal wall of the other hole, then redrawing the curve to make it reappear would be a tedious trial and error mouse movement ballet to get the program to draw in the correct x,y and z orientation.

Whew!

Dedication is its own form of hell.  
Kermit


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## Maryak (Jun 20, 2009)

I didn't know quite where to put this post - there have been so many in threads various which have helped me but "The Penny has Dropped" and I am on the way with 3D cad. I think it was a combination of Workplanes and realising that no matter how you orient the drawing the X, Y and Z axes are always in the same relationship to each other and a 3D object must have a Z axis.

From this humble beginning I hope to grow an engine.






Best Regards
Bob


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## kustomkb (Jun 21, 2009)

Well done, 

modeling parts in the computer helps me visualize and double check things alot.

And its alot of fun!


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## John S (Jun 21, 2009)

getting back to Viacad,

I downloaded the demo and had a quick look at it and decided to watch the tutorials, only problem was I only had 4 tutorials so did a search and fired a query off to Viacad and then decided to start doing a simple drawing of a PCB.

Had a bit of trouble getting a grid setup for 0.1" pitch so went for help - no help- Hang on windows program usually has help where you can click the second tab and it comes up with index to allow you to search, but not in Viacad.

OK so open the pdf and search in that, get the grid setup OK

Place text but it's too large, go to set text and it's user definable by default, set it to what I want and place more text but it now shot back to user definable instead of what I set ?

Can't see to find this in the manual.

Got a reply back from Viacad that they only supply the demo with 4 video's, the rest are on the paid for version ????????
How do I know I want to buy it if I can't see how it works ? Got a week of travelling coming up and watching these on the train would have been ideal.

Seems a funny way of working.

John S.


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## Cipsip (Jul 20, 2009)

I have a MK1 project that has its armor cut down so I will need to fabricate all the armor, has any one produced CAD drawings or dimensioned plans? Any help would be appreciated.


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