Tips about advanced Woodskills needed

why work with wood when you can work with clay?....easy to manipulate

think out of the box :lol:

first use clay, then when you are happy with the shape, take 2 casts of each side with plaster of paris

then with these 2 halves do your fine finishing

with these 2 finished pieces yo can do many things to make your exact master

you could strap the 2 plaster pieces together and poor 2 part expanding foam into it, but remember to leave a weep hole, and to use release agent/wax

the other method is to use fibreglass

the expanding foam way is quicker, and if yu cap off the plaster for a few minutes more the foam will set more dense, but remember to open the weep hole otherwise it will explode all over your work place

Getting back to the question of maintaining shape. If you are going to form a female shape, a starting point would be to make your two main axis shapes as templates. Then what ever material you start to carve, you can gage it as you go. I was spoilt with my first horns I did in the mid '70's. My patterns and master moulds were made by a pattern maker from Lotus cars. After a while, I just did them myself. The elliptical horn is more difficult. I did an elliptical horn, to go on the back of the lens in the old Concert System, I took it straight from the JBL horn that went on the back of their lens. You have to cheat once in a while.

you don't really have to even carve

if you were to make 2 jigs, and instead of moving the jigs/guages over the clay, you put 2 jigs either side of your lump of clay in line with each other

then get some fine wire (piano), while holding it taught, bring it down across the face edge of your two jigs

the do the following with the other 2 profile jigs

would take only minutes

anyway, enough of this, Bitzo don't like me teaching him things smiley3

cheese wire, not exactly going to find an old piano anywhere

just seen the second picture, so yes you will need to still do some carving, but at least you cab get your 2 profiles quickly
and you're half way there

Or a top E guitar string. Might as well keep it musical.

even better, because no one likes the smell of parmesan

this wire idea make me thinking....
I'm thinkig to build a frame just like a window door....then to it fix a lot of wire tangent to the shape of plug, then get heat by a car battery charger...so put in the frame a cylinder of foam then round it. Something like a lathe.
Uhmmm I have to check if foam is cheaper then mdf, and a glue to put the foam slice together.
However I modelled the 2 section plug, harder to model and build than the first one, it's like coaxial horn. I have to work a lot to make it buildable by a newbie like me.

mykey I like the stuff which anyone teach me. I lost the time to see the pictures :think: . Anyway Parmesan stinks, parmigiano reggiano and grana padano perfume . smiley16

nice idea mykey smiley20 . its got to be easyer then wood to shape..... smiley32

it's the way they build prototypes for cars....
to see how they react in wind tunnels etc

Didn't I mention foam when you started this?