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charlieuk
29-11-2014, 10:07 PM
without much success I have been trying to look in to some sort of scanner to use in conjunction with my cnc. What I would like to do is be able to scan existing surfboards that I have hand shaped and be able to replicate them the cnc and to make changes along the way.

I have used my machine with a disto attached and manualy moved the axis and taken mesurements at points but it is a very slow process

There are companies that already have this technology but I can find out many details and the threads that I have read seam to die before they get to a conclusion.

I think things like david scan will be out the question as some of the boards are up to 16' long and I don't have the space required to set up david.


There is a example in this video of what I would like to do im just not sure how complicated it would be ??

does any one have any experience of this?

many thanks

https://www.youtube.com/watch?v=NnLBXBG_Jr4

EddyCurrent
29-11-2014, 10:14 PM
Anything here any use ? http://usa.autodesk.com/autodesk-123d/
watch the video about '123D Catch' for a start.

charlieuk
29-11-2014, 10:35 PM
looks interesting I wonder how accurate it would be? the app doesn't seam to get great review but will look into it more

EddyCurrent
29-11-2014, 11:10 PM
We've been there before in this thread; http://www.mycncuk.com/threads/7842-laser-scanner-cnc-router-mounted?p=61215#post61215

Boyan Silyavski
30-11-2014, 12:39 AM
Now if you have made them, you should know all by heart. So it would not be difficult to design them with some Cad. I believe this is the preferable option.

Ok, you can scan them but the out put will be STL. So google now "how to convert STL to solid" , you see, not so simple and much time consuming.

Plus you will surely design new in the future. So the experience in drawing is needed. In short if i was you , i would draw them from scratch in some good parametric design capable CAD. The more you draw the faster you do it. And you will need the skill, for the first client that comes and wants something complicated.

charlieuk
30-11-2014, 09:55 AM
Drawing them is fine and I have a cad program for that there is even a add on program you can get specifically for scanning so it is just the hardware that I need to sort.

It is possible to do it manually but its taking the measurements that is the problem and its not just my own boards I want to scan, I also like to keep details of as may boards as I can that I have used and break down the designs to compare and it can take literally hundreds of measurements just to start with.

I have used a disto fixed to my gantry and moved it at increments and taken measurements but it is very slow and hard to get accuracy around tight curves.
It appears that most are using some sort of photoelectric sensor to take measurements but that is about all I can figure. The pro tools link looks to be in the right area but would like to know how much more there is to it as it looks like a photoelectric sensor too and you can get one from 50-200 pounds not 1500

edit: from my research apparently the camera style systems do not work well on objects that are relatively smooth surfaces as they find it hard to fix recognize the different point between scans

phill05
30-11-2014, 10:36 AM
Have you seen this http://structure.io/ you need an Ipad to use it but it works well.

Phill

Boyan Silyavski
30-11-2014, 12:26 PM
If you have an answer to what minimum scanning precision is acceptable, then its no brainer to find the proper scanner.

charlieuk
30-11-2014, 01:11 PM
.5-1mm range accuracy would be fine with a depth of around 350mm is the sort of thing I need

Boyan Silyavski
30-11-2014, 01:22 PM
Then all that stuff in the 300-600eur range is fine for you. The scanners meant for scanning person and make 3d prints and similar. cause when we are speaking 1500-2000, we are talking ~0.05mm or better precision.

Just have a look at Aliexpress (http://www.aliexpress.com/premium/3d-printer-scanner/2.html?g=y&needQuery=n&SearchText=3d%2Bprinter%2Bscanner&CatId=0&shipCountry=es&initiative_id=SB_20141130041537&prNum=0)

I believe something like this (http://www.aliexpress.com/item/Free-shipping-3D-scanner-3D-system-for-3D-Printer-3d-scannering-machine/32231288747.html)would be best for you.
PS:Now i am confused, it seems to be cheaper by half on other sites. Is this the same unit or the Chinese used the housing?Read reviews, some seem say it works just fine, most are not happy with the Sense.

-Its hand held, so you can go with your laptop to a shop and scan all the surf boards
-I have seen the results at a local shop.I believe same model or something very similar. Nice person 3d prints. Now i have not seen the proces, but i will be visiting him someday and see how its done froms scratch till the end, to see in reality if its worth the hassle.

I think that somebody who has used one of these will be best to fill us in.

charlieuk
30-11-2014, 02:29 PM
that looks like the sort of thing however it says maximum volume scan volume is 3x3x3 so not sure if that is the the volume of the area you want to scan or a max length in each axis. the same ones are on ebay for 300GBP

Edit : I have watched a few video and it does appear you are restricted by the scan area, it is possible to then mesh them together in can but I think if I am going to go to the effort to do it than I want the process to be simple and quick.

dazza
30-11-2014, 03:20 PM
if your looking to do this as some sort of business I say save your money, where decent scanning is concerned theres no cheap fix, what you think you saved in purchase you lose in time fecking about with scan after scan cleaning it up and getting poor results.
there all a bit of fun 3d printing and so on.
I came to this realisation a while back and ended up using two different companys to do my scanning.
when I eventually get one it will be something like the riftek rf603b this is what I consider starting point for what I need.
the lad ive used the most is in the link depending on how long it takes to do a scan it could work out cheap till you get sorted.
http://www.1-2-3d-scanning.co.uk/

EddyCurrent
30-11-2014, 03:27 PM
Take a side view photo then a plan photo of the board. e.g. http://www.mycncuk.com/threads/7823-How-to-get-panels-into-VCarve-Pro-7-5?p=60995#post60995
Import into CAD and trace the outlines or use Inkscape (free) to trace them. Orient the traced outlines on the X and Z azes then do a '2 rail sweep' to obtain a solid 3d model, Rhino3D does this great.
Use the control points on the curves to fine tune your shape. There are videos showing this.

This one uses the similar 'surface from curve network' ;http://www.youtube.com/watch?v=BRRIBptfFxg

I'm thinking you could make accurate cross section drawings at various points along the surfboard and the CAD software would draw the in between parts to create the solid model.

Clive S
30-11-2014, 03:59 PM
Would it be more accurate to use the hand held scanner fixed to the router to get a very smooth slow pass. ..Clive

charlieuk
30-11-2014, 07:49 PM
I don't mind spending the cash if its a good product and not over priced I would rather get it right first time than wase money on cheap half way solutions that end up wasting a hole heap of time. I have tried the photo method and its just not accurate enough to work from which I why I started taking manual measurements with the disto. I will contact prototools and see what they have to say about there product tomorrow. Basically it is just a series of cross sections I need to take down the board and one running length ways. It may be able to be done with some sort of probe even possibly?