Ovals or eliptical

garys said:

Can someone tell what the difference is between oval and elliptical is and how do you make one or the other. I have a head board with a name in it. The name is curved and I need to cut a oval (or ellipses) with the same curve or arc as the name around it. I would like to hear what would be the best way to go about it.

Thanks
The math dunce.

Click to expand...

Might want to check with mr webster but as I recall math people like to use ellipse and most people use oval and they both are for the same "egg shape" to add another name for it.

Now on to the problem...... I don't know of a good way to figure it out sounds like it might have to be a bit of luck and trying different sizes/shapes.

If you had a digital camera and could center yourself then shoot a picture and post it I could try and get something close in my cad package????

Maybe someone else has a better idea??

Ed

just another thought - the ******* Method!! possibly do a rubbing or tracing to use as a paper template - place on a piece of thin plywood or scrap MDF - sketch freehand shape following the outside shape - at points along this outline place marks perpendicular to the outline at the distance you want to be offset - put small brads or nails in along these offset points - use thin piece of plastic as a guide - place it upright against the brads and trace your line. Hope that makes sense. The plastic acts as a sort of template against the brads and as it curves it smooths out the line. Kind of like a free-form french curve.

Or use Ed's generous offer - problem there would be getting the scale correctly - he'd need some type of base/registration measurement - or possibly a ruler with large numbers in the photo to scale from.

(the geometry of an elipse is a form that has a large radius along the top and bottom with a smaller radius at both ends that is tangent to both of the large radii)

Ed, I do own a digital camera but I don't know if I could get the right picture for you. The oval will be about 4 and a half feet across so even if you did figure it out how would I print out the diagram. I think you may be right about the trial and error method but I will try to post a picture tonight for you to at least look at.
Gilbear I do understand what you are saying and I may try to use it.
I have seen a tool that will draw a oval but it says it is for up to 30inchs. If I could extend that to the size I want I may give it a try since I will be doing more of these only smaller.

Thanks for the responses
Gary

Gary and Ed -
If you could create a drawing with your software then dimension it along a line drawn from the center to the center at each end as a base line - but then you'd still be stuck with trying to create the smooth curves with a guide like I mentioned - see if this pdf makes sense - hope it's readable

I was wandering around and stumbeled onto this for laying out an elipse - thought I'd pass it on:

http://benchnotes.com/Laying out an oval/laving_out_an_oval.htm

Now thats more my speed. No math envolved on my end.
Thanks Gilbear that will work for me.

woodweb..../knowledge_base/A_Jig_for_Drawing_or_Cutting_Ellipses.html[/url]

best I have found

I doubt this 2 year old thread will assist the member at this point, but since it was dredged up there is a free plan available for building an elipse or oval jig. My computer is down for repairs and I can not access the plan at the moment but you can get the idea by visiting Rockler and looking at their jig. All that is required is a wooden square with two dovetail slots cut cross ways in it, two wedge shaped sections to ride in the dovetails with screws or bolts in them and a wooden strip for the guide arm. The photo's are self explanatory here: http://www.rockler.com/product.cfm?page=17282&filter=oval jig