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moh man
20th October 2011, 09:32 PM
Hi all,

What would be the best way to drill end grain. Im struggling to make candle holder, the part where you fit the cup for the candle.
Any ideas would be most appreciatted

mohman

TTIT
20th October 2011, 11:03 PM
Saw-tooth Forstner bit - 3/4" from memory. Or if you don't want to buy one, a sharp spindle gouge used the right way makes easy work of it. Please don't ask me to describe how to do it - I'm no good at instructions like that :no:

dr4g0nfly
21st October 2011, 01:54 AM
If you're going to use the spindle gouge method, I'd recommend drilling most of it out with the biggest 'Jobber' drill your jacobs chuck will hold (or you have) - probably 1/2" or 12mm.

Once done you can also clean up the sides and apply a slight taper by running the point of a 1/2" skew in and scraping the sides to the angle the metal cup is manufactured to.

moh man
21st October 2011, 08:05 PM
Thanks, got it sorted. I used a really good forstener bit. Im happy it drilled really good and no run out.:2tsup:

cheers

tea lady
21st October 2011, 08:11 PM
Thanks, got it sorted. I used a really good forstener bit. Im happy it drilled really good and no run out.:2tsup:

cheersAh yes! Sharp tools is usually the solution!:D So ya better show us your candle sticks soon! :cool: No pressure or anything! :D

moh man
21st October 2011, 08:14 PM
Ah yes! Sharp tools is usually the solution!:D So ya better show us your candle sticks soon! :cool: No pressure or anything! :D


Yup, agreed il post it soon....and now for some tea...lol

tea lady
21st October 2011, 08:39 PM
Yup, agreed il post it soon....and now for some tea...lolAh yes! A cup of tea is the other solution to everything! :cool: :D

rsser
23rd October 2011, 06:04 PM
Another tip that's been posted here is to use an auger bit. And maybe to file down the thread at the tip so that you rather than it is in control of the feed rate. Haven't tried it; just passing it on.

Bushmiller
23rd October 2011, 08:20 PM
Another tip that's been posted here is to use an auger bit. And maybe to file down the thread at the tip so that you rather than it is in control of the feed rate. Haven't tried it; just passing it on.

Ern

It is a good way. If you are using a hand held drill is is neccessary to file the thread as particularly in the larger diameters the thread wants to pull in too fast even on the slower setting and it will keep stalling even large drills and eventually burn out the motor. However on a lathe it is possible to spin at a suitable speed.

My son has been drilling 32mm holes in the end grain of dry hardwoods (mainly ironbark) and a speed of about 300rpm is ideal for that, but be prepared to retract the auger frequently as the flutes will not clear the shavings for very long.

Increase the speed as the diameter of the hole decreases. The advantage of the auger is that the hole has to be straight.

Regards
Paul

brendan stemp
25th October 2011, 01:16 PM
I reckon I've drilled more holes down end grain than most particularly with the recorders and grinders I make. Basically, if the drill bit starts drilling in the centre it is more inclined to follow the line of least resistance and continue to drill down the middle. So, my tips would be:
1/ make sure your tail stock lines up perfectly with your head stock.
2/ give the drill bit a good start by cutting a small countersink into the end to be drilled. I do this on the lathe using a skew chisel as a scraper. If tail and head stock are not aligned then this step will help overcome the problem by guiding the drill bit into the centre.
3/ start drilling with a short and therefore rigid drill bit. This will also help the drill bit to start drilling dead centre. I am often drilling up to 300-400mm down the middle of a 40mm square blank and will start with a short bit and then a longer one, and finish with an even longer one.
4/ I use twist drill bits for the recorders but you need to regularly clean the swath. This means extracting the bit every 20mm of drilling.
5/timber selection can be critical. If there is a big difference between the density of the summer and winter growth (as in radiata pine for instance) the the drill bit might follow the line of least resistance which will be the softer wood and this can throw the bit off course.

One of the best bits for drilling end grain are auger bits as the swath is cleared beautifully due to openess of the single flute. With these bits I drill as far as the quill travel will allow. It is simply not true that you need to file the thread off the tip when drilling on the lathe because both the wood and the drill bit are secured. In fact I have drilled with auger bits without the tail stack locked in place and, given you have the lathe going at a slowish speed, the thread will help to pull the bit into the wood and continue drilling unassisted. I dont like spade bits for this job because their shaft is too thin and flexible. Forstner bits are good but you need to regularly clear the swath. If you don't you can find the drill bit gets stuck in the hole by a compacted build up of swath.

TTIT
25th October 2011, 01:25 PM
........ Forstner bits are good but you need to regularly clear the swath. If you don't you can find the drill bit gets stuck in the hole by a compacted build up of swath.You need to give the Colt forstners a try Brendan :; They clear the swath faster and for much longer (ie: deeper) than any bit I've ever used :2tsup:

rsser
25th October 2011, 03:16 PM
They're in line for a play TTIT. Looking forward to it.

Thanks for the tips Brendan.

For pepper grinders I've used std high carbon or HSS saw tooth bits with a wood chopstick poked into the gap to help clear the shavings. This tip is courtesy of Bernie Kiyabu.

The downside with these on dense timbers is the amount of heat generated even when the bits are sharp. Have changed the colour of sapwood when present.

No, I don't have a compressor to provide some cooling air; prefer not to blow fine dust particles to where they can be breathed in.

old pete
25th October 2011, 05:18 PM
I reckon I've drilled more holes down end grain than most particularly with the recorders and grinders I make. Basically, if the drill bit starts drilling in the centre it is more inclined to follow the line of least resistance and continue to drill down the middle. So, my tips would be:
1/ make sure your tail stock lines up perfectly with your head stock.
2/ give the drill bit a good start by cutting a small countersink into the end to be drilled. I do this on the lathe using a skew chisel as a scraper. If tail and head stock are not aligned then this step will help overcome the problem by guiding the drill bit into the centre.
3/ start drilling with a short and therefore rigid drill bit. This will also help the drill bit to start drilling dead centre. I am often drilling up to 300-400mm down the middle of a 40mm square blank and will start with a short bit and then a longer one, and finish with an even longer one.
4/ I use twist drill bits for the recorders but you need to regularly clean the swath. This means extracting the bit every 20mm of drilling.
5/timber selection can be critical. If there is a big difference between the density of the summer and winter growth (as in radiata pine for instance) the the drill bit might follow the line of least resistance which will be the softer wood and this can throw the bit off course.

One of the best bits for drilling end grain are auger bits as the swath is cleared beautifully due to openess of the single flute. With these bits I drill as far as the quill travel will allow. It is simply not true that you need to file the thread off the tip when drilling on the lathe because both the wood and the drill bit are secured. In fact I have drilled with auger bits without the tail stack locked in place and, given you have the lathe going at a slowish speed, the thread will help to pull the bit into the wood and continue drilling unassisted. I dont like spade bits for this job because their shaft is too thin and flexible. Forstner bits are good but you need to regularly clear the swath. If you don't you can find the drill bit gets stuck in the hole by a compacted build up of swath.



That's all good advice from Brendan Stemp. I think that like myself he has drilled a few thousand holes over the years. When I'm doing critical drilling over a long distance I start the hole in each end of the blank using a good quality countersink. That gets the hole exactly centred and you are off to a good start. I use tool steel quality toothed Forstners for my grinders driling and you need to be ruthless about throwing them away when they just start to get blunt. You can't use those cheap Chinese Forstners for drilling grinders unless you only need a pair doing. The other secret is to use slow speed. I have VSD control that I set at 300 rpm but I often have to jerk it up a little during the drilling operation to keep the speed/torque up to the job> Drilling end grain is about patience and fastidious alignment of the headstock tail stock the bit and the blank and even then it doesn't always work out in material like highly figured Huon Pine that exhibits huge local variations in density. I've seen purpose made end grain drills with a step on the inboard end to drill the recess for the lower end of the grinder movement. I haven't got one but they are always based on 1" or 25 mm twist drills with a fairly flat grind on the business end. They are almost infinitely re- sharpenable fore long life compared to Forstners.

Good drilling Old Pete

rsser
25th October 2011, 05:34 PM
You don't need to throw away HC or HSS saw-tooth bits.

They can readily be sharpened. The former with a triangular file; the latter with a diamond paddle.

See Lee The Complete Guide to Sharpening.
.

wheelinround
25th October 2011, 05:51 PM
A hole saw is good for keeping it straight core the centre out with gouge and shape.

Bushmiller
25th October 2011, 06:47 PM
A question gentlemen. How long are these candlesticks? (or other long thingys with holes down the guts). Could have some bearing on the drilling technique.:)

Regards
Paul

moh man
6th November 2011, 12:10 AM
186795186796

Thank you all for your good advice.Here are some some of the pics of the finished product. My mate Dave was happy!!.....44 years old ...whiper sniper!

vk4
6th November 2011, 06:47 PM
looks good to me the joints are tight and clean , the finish is free of tool marks and sanding marks, .

Well done.

Jeff

moh man
6th November 2011, 08:19 PM
Thanks Jeff:)

D.A Hageman
25th December 2011, 11:11 AM
hi ya there ive mace thousands of candle holders and i nevver drill them on the lathe you can drill a hole in any end grain on a low speed if u place the hole on a spigot driver on your lathe there is not a problem with its centre regards dale