4mm t nut problem

[oceanobsession]

Hi folks, im looking to fit 4mm t nuts into 25mm birch ply first you drill a 4mm hole then you have to drill a 5mm hole so far into the wood to take the outer diameter of the thread, how do you make sure that the 5mm is in the centre of the 4mm hole, only unlike steel the drill does not follow the shamfer . cheers all phil.

 

[Spindle]

Hi

Use lip and spur bits and drill the holes from largest through to smallest.

Use a pillar drill if possible.

Regards Mick

 

[carlb40]

What he says ^^^

With timber you do it in reverse. So drill the 5mm hole. That will leave you with a centre point to start the smaller hole off.

 

[oceanobsession]

What he says ^^^

With timber you do it in reverse. So drill the 5mm hole. That will leave you with a centre point to start the smaller hole off.

I see what you mean, its for a speaker so I was hoping to drill through the speaker which has a 4mm holes I suppose if you place a flat
piece of steel under the wood and stop on resistence you will have a small starter at the back to use for 5mm, this could work I think.

 

[carlb40]

What he says ^^^

With timber you do it in reverse. So drill the 5mm hole. That will leave you with a centre point to start the smaller hole off.

I see what you mean, its for a speaker so I was hoping to drill through the speaker which has a 4mm holes I suppose if you place a flat
piece of steel under the wood and stop on resistence you will have a small starter at the back to use for 5mm, this could work I think.

Ahh i see the holes are pre existing then. Yes one option would be to use either a metal or even a piece of mdf etc with a 5mm hole. Centre that over the 4mm hole and drill through the template. Another option could be a step drill? - Except having just looked they go up in 2mm steps.

 

[oceanobsession]

The holes that hold the speaker in place are 4mm, and the best way to drill them accurately is to go through the speaker into the wood
if you place a flat piece of steel say 2mm at the back of the ply once the point of the wood drill hits the steel there will be a resistence, so then I would drop a bolt in and do the next once all are done turn the ply over and you will have a tiny point hole to start the 5mm hole.

hope ive made sense would this work

 

[Spindle]

Hi

I think you are over complicating it - why not just mark the centres of the holes on the back of the panel using the speaker as a template and drill as I suggested?

Regards Mick

 

[oceanobsession]

Hi

I think you are over complicating it - why not just mark the centres of the holes on the back of the panel using the speaker as a template and drill as I suggested?

Regards Mick

Good point that would work, cheers phil.