Thread: How would you drill...

Originally Posted by Artesano

.....a hole big enough for a bottle to get in? The wine bottles are about 80 mm. in diameter , and I usualy use a holesaw , but it's very limited in depth. This time I search for a way to drill the hole deep enough for the bottle , 200-250mm. Idealy I would be looking for a machine that could be clamped , strapped or fixed with screws to the piece of wood ( a tree trunk) , like some kind of a portable drill press , into wich I could fit some industrial grade drill , powerfull enough to handle 80 mm. bit (if such bit exists , that is )
Any ideas?
P.S.- It would be very nice if the thingie could be used in a small workshop , and purchased without the need for a mortgage

A small chainsaw with the right width bar and 25 mm rod or pipe bolted to the very end of the bar nose can do this.

Start by drilling a 25 mm hole into the wood where you want the bigger nose.

Clamp the wood firmly to a surface and insert the rod into the hole and while running the saw at full throttle rotate the saw around the rod often as you drive the saw slowly into the wood. (technical comment: For end grain it's best to have a near zero top plate cutting angle on the cutters - this will reduce vibration and give a better finish).

It sounds scary but it's not as bad as it sounds
This is a well known technique used by some fence builders.

A small electric chainsaw should be able to do this.

Use a forstner bit and go slow

A Forstner bit in end grain is no fun at all. Have a squint here: https://www.woodworkforums.com/f13/forstner-bits-44107/

The chain saw will leave a rounded bottom. A turner named Mark Lindquist uses the technique freehand. If that's acceptable, probably simplest. For a flat bottom, a lathe with captive boring bar would be cleaner, if the workpiece fits. You may need to attach a circular ring to the outside, to ride on a steady rest, if you wish to preserve a rustic outside.

Cheers,
Joe

This might be of use.

https://www.woodworkforums.com/f8/lon...-boring-83866/

use a chain mortiser to cut a square hole of the required depth and then cover the hole with a 20mm cover piece with a round hole in it
if you want to retain a grain match, cut the cover piece off the face side before boring the hole

Originally Posted by Ashore

Use a forstner bit and go slow

I use forstner bits in end grain quite regularly with good results, just remember, clamp it well and calculate your speed and you shouldnt have a problem

Thanks for the info folks
The lathe wouldn't work - I think about whole tree trunks , probably 500 mm. thick and heavy as they come , but the chainsaw looks promising. I have no problems with the rounded bottom of trhe hole , and even if the 25mm. guide leaves a smaller hole in the bottom of the big one , I'll have to live with that - any link to what the thing looks like? I suppose the chain will have to run trough the 25 mm. rod or pipe?

what about stitch drilling with a smaller bit and hollowing / finishing by dremel / hand / flapwheel in a drill / hand chisels...

just thought i'd mention since noone else had yet.

Neal.

Originally Posted by thompy

what about stitch drilling with a smaller bit and hollowing / finishing by dremel / hand / flapwheel in a drill / hand chisels...

just thought i'd mention since noone else had yet.

Neal.

....all the 30 or 40 holes?
Joking mate , don't shoot- but I realy want to make each hole in minutes , not hours.I checked that Forstner bits , and 80 mm. are available , what I'm don't know is if freehand drilling with such a beast is do-able.

Originally Posted by Artesano

....all the 30 or 40 holes?
Joking mate , don't shoot- but I realy want to make each hole in minutes , not hours.I checked that Forstner bits , and 80 mm. are available , what I'm don't know is if freehand drilling with such a beast is do-able.

Chainsaw takes ~ 2 minutes per hole

The tip of a small electric chain saw is about 50-60mm wide, so the bar or pipe will have to be offset to allow the chain saw cutters to reach a radius of 40mm. I think the best way to achieve this is to use a round bar with a flat milled or cut on one side for attachment to the chain saw bar, well back from the end of the cs bar so it doesn't foul the end wheel. Two bolts for attachment. Grind another region slightly deeper to clear the chain around the nose. Draw a cartoon plan view of the 80mm hole, the 25mm round bar (centered thereon), and the chain saw tip to get the picture.

For best control, I would have one person roll the log on a table or ground, while the other operates the saw. Probably two minutes to drill the pilot hole, and another two with the chain saw.

I'd use a cobalt drill bit to drill the bolt holes in the cs bar.

Cheers,
Joe

Hard nose Chainsaw bars are generally wider and have more parallel sides than sprocket nose bars (bars with little wheels on the end) and range in size from 65 to 100 cm wide. I have a 20" long bar which is 70 mm wide and a 30" bar which is 95 mm wide, so I guess there will be one that has the right size for you.

The hard nose bar can also be drilled very close to the chain rails and some already come with a hole in the middle of the nose.

Thanks again.I think I (finaly ) got the idea , and you made me discover a way of using the chainsaw I would never think of
I won't start drilling that log right now , this is a future projeckt I'm planning - I'll keep you posted when I start.