Quote:
Originally Posted by jimp  Hi Peter D,
My understanding is that, with the surface area of a hemisphere being twice that of its base circle, provided you use mesh with at least a 50% open area you would wind up with unrestricted flow.
Using flat mesh as you suggest, whilst easier to fabricate and fit, you will restrict the effective open area of your trumpet - and by a substantial amount if the mesh is only, say, 50-80% open area.
However, given that the trumpet is tapered, perhaps all you need to do is avoid restricting to less than the area at the narrowest point of the trumpet.....???
Regards,
Jim |
I fully agree with your approach Jim, I have tested some months ago both systems and the hemispheric grid is a little more efficient than the flat one (mainly at the top end). To be honest I have to precise that I was obliged to cut a little the original Weber trompets to have enough space to install the tea balls and this modification can also contribute to improve power at the top end. Here below one picture of my first mesh grid adaptation on one after market horn (as you can see, I use the "modern" Weber IDF type
). I have to precise that it was difficult to crimp the flat mesh and it was the reason why I have used silicon to seal tea balls.