Planimeter

Here's one for you. Considering I am in the UK, does anybody know a place where I can get a planimeter, preferably cheaply as poss. Also, in the mean time, and whilst I'm saving to buy one, what are the alternatives which get the most accuarte results. There must be some surely???

 

Try www.macnaughtongroup.com/yds_drafting_tools_order_form.htm

 

planimeter Cheep

Since you said cheep, try www.ebay.com. Last time I checked they had 13 of them listed.

Cheers;
Mike Schooley

 

Simpsons rule

You can always use Simpsons rule, it's an averiging system that works really well on irregular areas, thoogh not as exact as a planimeter but still useful.

I'll post an example later

Erik

 

Although this may be mixing technologies, when working on an initial design, I like to work using splines and ducks, this gives a better feel for what is going on, before transfering to a design package, HOWEVER I develop sections in Autocad, since I can instantly calculate the area and compare with my SAC, then print off and trace into my lines plan.

On this basis, you could Scan your sections, strip them out, and use the area function in Autocad, an added benefit is that it can calculate the properties of the area as well.

 

Sounds a good idea. What sort of price is AutoCAD, and ae there any budget packages that will do the same job if it is expensive? (P.S. I know I sound relly tight, but what the hell

 

AutoCad is ~$3000. If you are a student though you can get a good deal on most AutoDesk software (for example through http://www.journeyed.com/ or http://www.campustech.com/ in the US).

 

I should let someone else answer this, but until they do, I'll add that there is an LT version of AutoCad (2D only) for much less money, but it's still pretty steep for a 2d-only program (though you do get familiar with AutoCad if you later want to move to the full version). Value-wise you would be better off with Rhino ( www.rhino3d.com ) or something like Turbocad ( www.turbocad.com ) or IntelliCAD ( www.cadopia.com ) (But I'll qualify this post by saying that I have no experience with the latter 2 programs in a long long time and only a little time spent with Rhino so far, so as I said, I should let someone else give you a better recommendation.)

 

When I said Autocad, I meant Autocad LT! which has these functions. Although it is not inexpensive, it is good and for yacht drafting is fine, Autocad or rather .dxf is the industry standard.

All the yards I have worked with use it, as they will not pay the £ 3000 for full Autocad!

 

does anybody know, then, if Rhino has the functionality to scan in drawings, and work out the area of irregular shapes?

 

Yes, you can import the file as a .bmp file trace it over then turn the curve into a surface and find the area. I did it few times and it worked fine. I checked the result manually with a planimeter.