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dudz
09-11-2015, 01:10 PM
This must have been asked before....but doesnt come up on search.

Does there exist an affordable Cad pen, to create cad drawings freehand ?.
I remember in the days of the commodore 64 PC, we had light pens that worked by drawing straight onto the pc/tv screen (before LCD)

komatias
09-11-2015, 01:47 PM
yes you can get graphics tablets. They are ok for artists, not sure how they work with CAD packages.

suesi34e
09-11-2015, 01:59 PM
Calcomp make CAD based tablets. I imported one from America for CAD but I was a big waste of time and money to me, that said my one was used and I did not get it working. Not through lack of trying!

dudz
09-11-2015, 02:14 PM
Ok. I was thinking more of without a tablet. Maybe a mouse like this for moving over a plan. If I trace the outline of an awkward part onto paper, then I could possibly use this mouse to trace and then upload it. Then apply any details after.

http://www.amazon.co.uk/367/dp/B0020ZK6MU/ref=sr_1_25?s=computers&ie=UTF8&qid=1447078177&sr=1-25&keywords=cad+mouse



(http://www.amazon.co.uk/367/dp/B0020ZK6MU/ref=sr_1_25?s=computers&ie=UTF8&qid=1447078177&sr=1-25&keywords=cad+mouse)

Neale
09-11-2015, 05:26 PM
Looks to me as if that mouse is designed to be used with a Wacom tablet, not as a normal mouse. Could be wrong but needs checking?

I needed to make a cutout in a piece of wood to mount an irregular shape piece of pottery tile. I used my scanner to get a bitmap image and then used a trace feature in a CAD package to end up with a DXF. The scanner output needed scaling (it came out as something like 97% of the original) but once I'd tweaked it, it worked very well. Just a thought - it all depends on exactly what you are trying to do.

Packages like Fusion360 and OnShape do make drawing easier than with a more traditional package like TurboCAD. You "sketch" shapes like rectangles and circles, then snap them together, add corner fillets, then dimensions, and you can pretty quickly end up with quite complex shape, all fully dimensioned and with the ability to edit very easily. I remember light pens and the like from dedicated graphics workstations from what seems like long ago now, but on the whole I would rather use a mouse and a good CAD application.

alboy
09-11-2015, 10:19 PM
well you can get digitisers but they are mucho expensive, see here. http://www.logicgroup.com/LogicTrace/Digitizer.html?gclid=CNehpJCvhMkCFeVz2wodc7sDug

graffian
10-11-2015, 05:07 AM
I bought a Wacom[cost 12 quid from the local paper] to do the shading in a logo I was painting on something, it worked pretty well but my lack of artisticness showed. Since I have the tablet I have seen posts about using them for CAD, not that I have tried. I think people use slightly larger and newer ones than mine. Mine just has the two buttons on the pen, but I gather some have a menu area on them. With the Wacom I could draw lines far better than I could with a mouse, and I could vary the line width if I wanted.
I get shapes like manifold flanges into the pc by tracing them on white paper with a fine pen and after scanning them I draw over the TIF in cad. I did try the livetrace option in illustrator, I found it slower.

njhussey
10-11-2015, 07:04 AM
I looked into the same thing a while back as I wanted to get an RC plane plan and put it on a surface and trace over the outlines etc with the mouse/puck. I remember back in the late 80's early 90's being at uni and using a tablet and puck for cad....on a Commadore 64. There are tablets out there but as been said their blinking expensive!

dudz
10-11-2015, 08:40 PM
Maybe I will wait until all the existing technology inc 3d scanners come down in price......maybe 5 years from now

magicniner
10-11-2015, 10:41 PM
Maybe I will wait until all the existing technology inc 3d scanners come down in price......maybe 5 years from now

Or you could scan or photograph it, resize the image appropriately, then import the image into a CAD program, from there it's quite quick to create an accurate drawing,

- Nick

dudz
25-11-2015, 06:41 PM
Or you could scan or photograph it, resize the image appropriately, then import the image into a CAD program, from there it's quite quick to create an accurate drawing,

- Nick


Sounds feasible
Any free cad that does this ?

njhussey
25-11-2015, 07:04 PM
Draftsight does, its what I use to do drawings of RC planes.

magicniner
25-11-2015, 10:42 PM
Good to know there's a freebie option, I use BobCAD-CAM V25 for 2.5D, 3D & 4-Axis stuff so I bought the art package with a view to engraving work, it turned out to be of more use for 2D part replication ;-)

- Nick

graffian
27-11-2015, 05:47 AM
I looked into the same thing a while back as I wanted to get an RC plane plan and put it on a surface and trace over the outlines etc with the mouse/puck. I remember back in the late 80's early 90's being at uni and using a tablet and puck for cad....on a Commadore 64. There are tablets out there but as been said their blinking expensive!

I remember something similar in the 80's, a bloke I know spent a bundle of money on a vinyl cutter and computer[they will never catch on].
I never took much notice of it, I was there when he did a van for a local motorbike shop; he drew a logo free hand with pencil and paper, then he went over it with a thing with a lens with cross hairs. I think he had to press a button at points and it created it on the screen.

magicniner
27-11-2015, 08:48 AM
Time, and software has moved on. With the quality of digital imaging now available, and with the advent of packages with a good "Trace" function capable of generating vector outlines from bit-mapped images, the time of "digitising tablets" for accurate generation of technical drawings is well past it's sell-by date.
Starting with a scanned image or photograph I use Photoshop for bit mapped image sizing, manipulation and processing then Illustrator for vinyl cutting vector art generation or Bob-Art for machining jobs.
The only potential problem when photographing parts is distortion of the image caused by short focal length lenses, and/or having the focal plane too close to the object, by using at least a 50mm lens with the focal plane at least 1m away for parts up to 100mm length the results are good. For larger parts hanging on a wall and using a telephoto lens from longer distance would make sense.

- Nick