Dear DAVID Community,

As you are probably aware, the entire DAVID company, team and product range has been integrated into HP Inc.
This forum is now read-only. Relevant content has been migrated to HP and merged into HP's Support Forums on November 1, 2016.

To start new discussions for 3D Scanning, please register and post your new topic at the HP Support Forums

Scan to CNC

Questions, problems, comments and tips regarding the 3d scanning process.

Scan to CNC

Postby Jerry In Maine » Thu May 10, 2007 1:45 am

Some "If" type questions:

IF I get a good camera and a decent laser source...
-and-
IF I carefully follow all instructions and tips here...
-and-
IF I practice until I get all performance that DAVID can offer...

Could I potentially get scans (of simple objects) that I can use on my CNC router with decent results?

I just finished building the CNC wood router - and have choked at the price of some of the "3D" images available for sale. They're nice (still life, animals, floral outlines, etc) but hard to justify on a hobby budget.

I was curious if DAVID would potentially offer me a means to make my own images suitable for routing.

Anyone else currently doing this?

Thanks -
Jerry In Maine
 
Posts: 19
Joined: Wed May 09, 2007 4:19 pm
Location: "Down East" Maine, USA

CNC routing

Postby CliveB » Thu May 10, 2007 5:43 am

Hi Jerry,


my answer is definately Yes.

you have to make sure that your model is stitched together well and that there are no open edges. My presumption is that you are using the Stl file format for your cnc machine. I don't know what program you are using for cleaning up the model but you can download the free Wings3D program
( www.wings3d.com) to fix the obj model.

I hope this helps


Cliveb
CliveB
 
Posts: 121
Joined: Wed Mar 28, 2007 4:12 pm
Location: Toronto, Canada

Postby Jerry In Maine » Thu May 10, 2007 1:10 pm

When shopping for a laser...

Other than shopping for a generic laser-level, is there a specific range of specs that are best for use with DAVID?

Reason I ask is that hobby-type surplus electronic suppliers often have laser products (out of various OEM gear) for decent prices. As a bona-fide "tinkerer" I often find myself scrounging through their catalogs and websites. They sometime lists the specs and this could help in selecting one that's ideal.

I would imagine that I'm looking for a particular range of wavelength, intensity and beam spot diameter. Anyone know of a optimum range on these?
___________________________________
"I'm just a number in a great design..."
Jerry In Maine
 
Posts: 19
Joined: Wed May 09, 2007 4:19 pm
Location: "Down East" Maine, USA

Postby WalterMo » Thu May 10, 2007 7:19 pm

Hallo Jerry,
Please have a look at my posting of April 14 in the column "Red or Green".
The power of the laser depends of what colour the surface of the to scanning object has and how large it is. 5mW should be sufficient.

Walter
User avatar
WalterMo
Moderator
 
Posts: 2363
Joined: Mon Apr 02, 2007 6:52 pm
Location: Braunschweig, Germany

Postby Jerry In Maine » Thu May 10, 2007 8:55 pm

Thanks!
I find a 650 nm @ 10 mw on ebay at < $20,00 shipped. This is a lot cheaper than I thought...
Can the laser be too "hot" in intensity?
___________________________________
"I'm just a number in a great design..."
Jerry In Maine
 
Posts: 19
Joined: Wed May 09, 2007 4:19 pm
Location: "Down East" Maine, USA

Postby WalterMo » Thu May 10, 2007 9:07 pm

Yes Jerry it can,
read my report to the scanned ear model.
I think a CMOS camera is easier to overdrive than a CCD camera. But there are only a few CCD Web Cams on market.
User avatar
WalterMo
Moderator
 
Posts: 2363
Joined: Mon Apr 02, 2007 6:52 pm
Location: Braunschweig, Germany

Postby Simon » Fri May 11, 2007 10:24 am

Alternatively you can look for a camera with an adjustable lens aperture (iris). Then you can avoid oversaturation by closing the aperture. But normally the cheap 5-10mW lasers are not too bright.
User avatar
Simon
DAVID Developer
 
Posts: 423
Joined: Sun Jan 21, 2007 3:40 pm
Location: Braunschweig - Germany

Just how detailed han you get

Postby CAMCOMPCO » Sat Jun 02, 2007 4:41 am

I wish to use DAVID rather than a digital prob to scan 3d objects, convert them into some dxf or stl format for reading into autocad (or turbocad, etc)

What is the greatest level of separation I could obtain...0.1 mm, 0.01mm, etc...In essence, what is the smallest object I could separate into two distinct contours?

Also, what hardware recommendations would accompany this capability?

Thanks much...PS Major newbie to David....

John
Insanity is doing the same thing over and over and expecting different results - Albert Einstein
CAMCOMPCO
 
Posts: 2
Joined: Sat Jun 02, 2007 4:34 am
Location: Chicago, Illinois, USA

Postby WalterMo » Sat Jun 02, 2007 1:08 pm

Hallo John,
Some days ago I have scanned both sides of a coin (see User Gallery). The maximal elevations were less than .1 mm. With some more extravagance it should be possible to detect details of .01 mm.
But this result you cannot achieve by freehand scanning. You should use a translation stage with a fine resolution and a high resolution firewire greyscale CCD camera. A very stable set-up is an assumpion.

Walter
User avatar
WalterMo
Moderator
 
Posts: 2363
Joined: Mon Apr 02, 2007 6:52 pm
Location: Braunschweig, Germany


Return to 3D Laser Scanning

Who is online

Users browsing this forum: No registered users and 3 guests