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Mike N
11-18-2006, 09:57 PM
I want to carve 12 seperate pieces with each having the same design but I want each to have an arc of 30 degrees. Each piece I want to be maybe about 2 inches wide. When I'm done carving I will cut each with angles and glue them to put into a ring as part of a vase I am going to turn on my lathe. If anyone knows what I'm talking about or knows how to do this Please help. I tried but CW does not show me what the arc is of the curve, at least I don't know where to find it.

thanks
Mike N

Greybeard
11-19-2006, 06:14 AM
Hi Mike.
I hope I've got your problem correct. You want to include in your turning a carved section about 2inches deep(you don't say what diameter though).
This is to be made up of 12 sections, truncated wedges of 30 degrees, which have the outer surface curved to be the correct diameter.

I've attached what I think is the key element your looking for in the cw software. If you draw a rectangle on a new board, click on the surface tool and choose horizontal dome. Set it to 0.5 inches deep. Pull the rectangle to the lower edge, then use the isometric tool to tip the board up so you can see the curve you've chosen. If you run your mouse over the surface you'll find the curve is 0.5 at the sides and 0.4 at the centre.
If you now shrink the rectangle so that it's narrower, you'll find that the two depths are still the same.
So, by choosing the correct depth and width of the rectangle, you can generate any cylindrical surface you want.
You'll need to use a draw programme to work out what cross section is right for your project.(or use pencil,compasses and paper !)
Shout if you need anything explained in more detail.

John

Greybeard
11-20-2006, 07:01 AM
Last night I thought I'd better try out the idea with a carving planted on the curve. If you give the pattern the same depth as the surface then an additive merge brings the carving neatly onto the surface.
John

Mike N
11-20-2006, 12:27 PM
John, thanks that helps out alot. But one major thig I need to know is what is the arc of that curve such as 30degrees. For example if I wanted to cut 12 of those pieces that you did then I would need to make sure that they are each 30degrees to fill a 360degree circle. I cannot find anywhere in the software that tell me the degree of the angle.

I hope I explained that OK.

thanks
Mike N

Greybeard
11-20-2006, 02:01 PM
How I set up the project was to start in coreldraw and draw a circle and convert it to a 30 degree arc. Drawing a rectangle round this gave me the height and width of the arc.
This then gives the dimensions to set up in Designer. So doing it this way round, you don't need to have Designer give you these sizes.
Is this ok?
If you give me the diameter that the carved surface needs, I'll give you an example.
On the practical side, I'd cut the blocks out first with the 30 degree angle ready done. Do a dry assembly to check, then mount them on a board for the machine to carve.

John

Mike N
11-20-2006, 02:25 PM
John, thanks that helps, I quess I will have to use Corel, hopefully Adobe Photoshop has something like that so I don't need to but Corel. I really wish CW would just ask what arc I want. I really don't know how big these are going to be for each project I just know the arc I need. Some will be 8 segments and some 12 and it also depends how wide I want the bowl also.

An example would be a 8inch bowl would need 45degree angles. So I will need to carve 8 pieces with an angle of 45 and mayby a width of 1.5 inches. Where I'm going to run into problems is figuring out if 1.5 inches wide would do for an 8 inch circle. I should have paid more attention in Hihg School math class.

Mike N

Greybeard
11-20-2006, 03:08 PM
Mike does this help ? This is for 12 pieces around the circle with a 30 degree arc.
(I strongly suggest that a pair of compasses should be on your next shopping list :D )

I've just thought of another problem now that you have mentioned the word bowl. Is the carving going to be on the outside, around the rim ?
Are you intending to start with a solid block made up of segments, or with a partially shaped, hollowed block ? I'm thinking of the thickness limit of 5" timber throught the cw. The pieces that will have the carving on could be cut from quite thin timber if you have more of them round the rim.
I'd be happy if you want to send me a pm with details.

John

Mike N
11-20-2006, 03:25 PM
John, I know exactly what you are saying in the word "bowl" problem. For now I just want to use these carved segments for eith the top or bottom so they won't be at an angle. Maybe when I get good at this I will worry about putting them at a vertical angle.

As for the thickness... I am thinking I'll use a 1inch board and hopefully have a half inch or more left to glue the segments together. Then I will carve the inside of the bowl maye to 1/4 inch thick. As for the outside I am thinking that I will not have to carve anything on that ring because hopefully the 30 degree or 45 degree angle will all mattch up. Thanks soooo much for your help on this. I'll keep in touch and tell you how it works out. Hopefuuly someone from CW is reading this and get get the arc angle in the next version to either show me what it is based on my dimensions or let me put in the angle I want.

Mike N

Greybeard
11-20-2006, 03:34 PM
Happy to be of help :D
John

Dan-Woodman
11-20-2006, 04:09 PM
Mike
There's a good website for drawing segmented shapes,at www.benchnotes.com scroll down to where it says information,then on the right it says GEO-SHAPES it shows how to drawout the diameter of your project , then divide it into segments, and it tells the width of each segment. nice website.

Greybeard
11-20-2006, 04:22 PM
Hi Dan - I've never come across that method for creating a five sided figure with a compass before - nice one :D

John

Dan-Woodman
11-20-2006, 04:55 PM
Hey John
That 5 sided object looks like it would be a fun project with carvings on each flat side and then turned into a vase or whatever, one tricky part would be the 36 degree's. I saw the other day that Woodcraft has a new digital angle gauge for under $40.00 that attaches to your sawblade and reads out the angle in one degree increments. That seems like it would make it easy . OK SANTA?