Thread: Nasty hole redrill problem - 42mm Merbau

Are you using forstner bits?

If so, I'd drill a 19mm hole in a board and clamp it to the bench-top to use as a pilot for starting the bit off centrally in the 18mm holes.

Hmm - that's a great idea. Yes, I will use a Forstner bit so those doggies get a smooooth life! )

Thanks for that - problem solved! Now it's just for me to apply my ham-fisted magic and see what incredible mess I can make of this from here!

Many thanks and cheers,
David
PS. If I hadn't just had a significant tool buying frenzy I'd go purchase a significant drill press! )

Originally Posted by deldridg

Hmm - that's a great idea. Yes, I will use a Forstner bit so those doggies get a smooooth life! )

Thanks for that - problem solved!

Usual disclaimers apply: I'd test it on a scrap piece first.

I hope it is problem solved. I can't foresee any problems, but that's how I get myself into similar messes in the first place!

Much appreciated - will post how it goes! )

David

Agree with Skew's solution. Should work well as long as your board is at least as deep as the bit.

The problem you face is that there is nowhere for the centre of the bit to run. Another solution to this type of problem is to replace the missing timber by gluing a 18mm dowel into the hole. You can then redrill the hole to 19mm with the bit fully supported.

Regards

Larry

Originally Posted by Larry M

David
The problem you face is that there is nowhere for the centre of the bit to run. Another solution to this type of problem is to replace the missing timber by gluing a 18mm dowel into the hole. You can then redrill the hole to 19mm with the bit fully supported.

Regards

Larry

That's what I would do as it's very difficult to drill out an 18mm hole to a 19mm hole. Easier after the whole has been fillede.


Peter.

Thats what I would do too.

I would take the bench dogs to a machinist and have him whip 1mm off them.

Good Morning David

I have been thinking about your problem for a week and basically agree with Larry's suggestion to plug the holes with dowell and re-drill them the correct size. If you try to drill without plugging, IMHO it will be almost impossible to stop the drill from wandering.

However 3/4 inch is actually 19.05 mm - If you drill a new 19mm hole then you may find that the 3/4 inch bench dogs are too tight a fit. You may need to get the marginally larger 3/4 inch forstner bit.

Remember, your bench will be you most important tool for a very long time.

Cheers

Graeme

Originally Posted by Skew ChiDAMN!!

Usual disclaimers apply: I'd test it on a scrap piece first.

I hope it is problem solved. I can't foresee any problems, but that's how I get myself into similar messes in the first place!

Yep me too works a charm, also good for hole saws if you dont want a center drill hole in the offcut!

why not just sand the holes, 1mm is not that much to sand off. all this drilling / pluging is a lot of work

Had a thought about your problem.

While I would have to agree with Groggy that the idea to slim down the dogs would probably be the easiest it would still leave you with the problem that the same would need to be done to any later purchases.

Consider this method - make a square frame which captures your router base allowing no sideways movement. Using a 3/4" bit [mine measures 19.14mm / 0.7535"] locate the frame so that the bit is centred over your hole, clamp the frame and plunge the bit into the hole. This should give the correct size with little or no damage to your existing 3mm chamfers which could then be redone if you feel the need.

Should be able to be done relatively quickly and efficiently. If you don't have a router then perhaps it would be a good time to purchase one of these invaluable tools - just remember that good bits may be expensive but as a rule good bits do a great job.

Regards,
Bob

You are right, and I probably should have put a smilie on that post Bob. I was just putting a lateral thinkers perspective on the problem.

Your solution seems a good one.

I recon everyone is over reacting. You already have an 18mm pilot hole...the 19mm bit is going nowhere except straight down.....too easy.