Holes for Neutrik D XLR

Has anyone tried using a 15/16" punch or step bit to make holes for a Neutrik D chassis mount XLR connector? Neutrik D connectors require a 24 mm hole. 15/16" is 23.8125 mm. Will the 0.1875 mm difference give me a hole too frustratingly small for the connector to fit?

I think I just answered my own question. The Neutrik D connector actually requires a 23.6 mm hole. 15/16" is 23.8125 mm so it should work, right?

yes it will work. use a round file to enlarge hole if needed in any case

dave yourself some trouble and get a step bit also known as a uni bit. It can do holes in various sizes and depending on which bit can do the size you need and then some. worth the 40 bucks they cost.

A 15/16" spade bit (wood bit) in a drill press makes a perfect hole in aluminum panels. Clamp the panel between two pieces of MDF. The hole in the top piece of MDF acts as a guide to keep the bit from wandering. Line up the point of the bit with a pilot hole, clamp the panel, then position the predrilled MDF and clamp it. A drop or two of dish washing liquid makes a good lubricant. The cutting is done by the little points at the end of the bit, so if the material is too thick, it won't work. Home Depot sells individual spade bits. Cheaper than a punch, cleaner than a cheap step bit (though they work fine, too).

Drop a connector into the hole, secure it with tape, then use the screw holes as guides for drilling the mounting holes. Measuring never works for me...

FWIW I have never managed to make a clean hole larger than say 16mm with a step drill, especially in the back panel which is usually made of steel. I finally caved in and ordered a hole punch...

The Qmax punches widely available in the UK are only easily available from Canford Audio in the 24mm size - most suppliers only stock 25mm punches, which will 'show' the edges of the hole around the connector.

I use both 24mm punches and Starrett type hole saws - on aluminium die cast boxes the hole saws are usually quicker and easier.

With respect to the mounting holes, it isn't too difficult to mark the hole positions - centre punch the mark, then drill using a 2mm size, then enlarge to 2.3mm with another drill.

This hole can then be tapped M3 - making it really easy to fit the machine screws. I like stainless steel screws, which are easily to find.

If you drill the screw holes to 2.7mm, you can use thread forming (eg. Taptite) M3 screws, which saves tapping them.