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Dammit Nimrod. Your mad mechanical skills just make me feel like a poser. Elegant and simple. I did the previous method on some cabs yesterday and liked it. Yours is better. Did you add gasket or some dampening along the unsupported edges of the grille?

LelandCrooks wrote:...Did you add gasket or some dampening along the unsupported edges of the grille?

Nothing added to the grill edges. they are solid and don't touch anything. I only notched out sections on the top and bottom to make room for the tweeter horns edges.
(the grill's back foam actually sits flush against the face of the tweeter horn flanges) see here:



Here's a close up pic of the grill-cab fit and one of the bottom feet (you can barely see the grill's mounting block):

Probably a stupid question, but do you own a metal brake (bending tool for sheet metal...I think it's called that). Those edges are perfect. It's pics like those that help me to learn. Thanks for sharing them.

miked wrote:Probably a stupid question, but do you own a metal brake (bending tool for sheet metal...I think it's called that). Those edges are perfect. It's pics like those that help me to learn. Thanks for sharing them.

he said he had a metal shop cut and bend it for him

Yes, he did. I missed that. Thanks.

So what do you guys do to cut a grill in a straight line? I have grills from larger cabs that I want to cut down to fit my WH8s. Any jigs/tips/tricks for that? I can cut a straight line in a panel of plywood, but have no idea how to go about with the perforated steel.
I have an angle grinder but the results wouldn't be pretty

If it is heavier stuff (16ga and up), use an abrasive blade on a skillsaw with a sled. You'll have to clean the flash off the cut edge, but it will be straight. If it's thinner stuff, either cut with a pair of aviator snips or score it with a razor knife and bend it off. The scoring method works good, but you'll need to clamp the metal in between two pieces of lumber right next to the cut line. Although, I can't imagine that anything thinner would be a good idea on a stage monitor.

I'm not used to think in gauges, but I'm pretty sure the razor knife would not cut this. Abrasive blade and panel jig, I hadn't thought of that. Thanks!

N.Webber wrote:

LelandCrooks wrote:...Did you add gasket or some dampening along the unsupported edges of the grille?

Nothing added to the grill edges. they are solid and don't touch anything. I only notched out sections on the top and bottom to make room for the tweeter horns edges.
(the grill's back foam actually sits flush against the face of the tweeter horn flanges) see here:



Here's a close up pic of the grill-cab fit and one of the bottom feet (you can barely see the grill's mounting block):

Good Lord, that's gorgeous!

AntonZ wrote:So what do you guys do to cut a grill in a straight line? I have grills from larger cabs that I want to cut down to fit my WH8s. Any jigs/tips/tricks for that? I can cut a straight line in a panel of plywood, but have no idea how to go about with the perforated steel.
I have an angle grinder but the results wouldn't be pretty

I clamped the grill between two pieces of 1x4 and used my jigsaw with a fine-tooth metal blade running right along the edge of the 1x4s......it went way better, faster, and cleaner than I thought it would when I started.

I have a 24" brake, handheld shear, and aviation snips. All gathering dust. I order my grilles.

jimbo7 wrote:

miked wrote:Probably a stupid question, but do you own a metal brake (bending tool for sheet metal...I think it's called that). Those edges are perfect. It's pics like those that help me to learn. Thanks for sharing them.

he said he had a metal shop cut and bend it for him

Indeed. I ordered these grills directly from a punching shop. They actually CNC-punched them from raw sheet according to my specs, hence leaving the folded edges un-punched.

I have cut grills for other cabs from stock perforated sheet using an angle grinder running along some straight edge clamped to the cut line.
I used 1.5mm (1/16") cutting disc and the cut comes out really nice. A pass with a cup steel brush takes care of the remaining sharp bits.

This method is the one I would like to employ for my OT12's.
The issue with the OT12's is the ID of the cab is obstructed by the angle of the horn panels. If I were to have the metal mounting blocks along top and bottom (4 in total), and omitted the folded edges of the grill along the sides, thus not affixing the grill at all along the horn panels, does anyone think this would be successful in terms of having no vibration issues?

commander_dan wrote:This method is the one I would like to employ for my OT12's.
The issue with the OT12's is the ID of the cab is obstructed by the angle of the horn panels. If I were to have the metal mounting blocks along top and bottom (4 in total), and omitted the folded edges of the grill along the sides, thus not affixing the grill at all along the horn panels, does anyone think this would be successful in terms of having no vibration issues?

Would the edges of the grill, along the horn panels, be bent at all?

Initially I was thinking that I would omit the grill edge along the horn panels, but now that I've thought about it a bit more, I don't see a reason why I couldn't include grill edges matched to the same angle as the horn panels, thus being able to put mounting blocks along those edges. The trick will be finding a shop that can do the folding in Perth for a reasonable price.

Can someone please confirm the required angle for this? is it 35 degrees?

Cheers.