clock inserts and forstner bits

[gilljc]

Anyone have much experience drilling holes for clock inserts? the first two clocks I made used an insert to fit a 50mm hole, and the only forstner bit I had was marked 51mm, which fitted a treat. I have two different inserts that are sold as fitting a 60mm hole, so I bought a 60mm forstner bit. The cheap looking plastic one (which actually cost more) fits the hole fine, but the lovely slim line metal one with a gold face just will not go in
I have searched online, but can't find a 61mm forstner bit, any suggestions?

 

[NazNomad]

62mm any good? http://www.amazon.co.uk/Tungsten-Carbid ... B0064P0G9U

 

[martinka]

Why not cut the hole with the scroll saw, Gill? Or isn't it that simple?

 

[ChrisR]

I don’t have any large forstner bits, so I mark out the cut out required, then remove most of the stock making multiple plunges with the largest/most suitable bit I have, then trim the remainder with a very sharp chisel.

I use the same method when cutting out bowls with a router, (saves the router a lot of work), I know this is not scroll sawing, but thought it related to the above,( ie) removing stock, for which you do not have a suitable/large enough cutter bit.

Hope this is of some help.

Chris.

 

[AndyT]

Wrap some 60 grit abrasive paper round an offcut of plastic waste pipe or anything else round that you can find. Scrape it round inside your 60mm hole a few times until the insert fits.

 

[beganasatree]

Hi Gill,
I had the same problem some time ago.But With some 80 grit paper the 60mm was soon big enough.

Peter.

 

[gilljc]

Thanks a lot guys, lots of good ideas there, and will probably give them all a try. I didn't want to cut a hole with the scrollsaw because I wanted the back to be plain.
In the meantime, I took off the good quality rubber thing from round the edge and replaced it with a rubber band, bit uncouth but it works for now :wink:

 

[CHJ]

One of the many cheap sanding drum kits would make such tasks as adjusting blind hole size easy.

Axminster do more exotic/expensive versions that use flat strips.

 

[beganasatree]

Hi Chas/Gill,
I have a kit from Axminster it is the same as the Screwfix one but replacement sleevs are not always available,so I now make my own drum sanders .I turn a bit of wood to the Dia that I want then drill a small hole just smaller than 1/4",I then push a 1/4" hex screwdriver bit into the wood and then glue on the abrasive .When the bottom section is worn out I cut that away and move up the drum until it has all been used,break the wood from the screwdriver bit and start again.I also use the same sort of thing for my sanding arbors,150"driver bit,conical shaped bit of wood,foam rubber,and some velcro.

Peter