Alternative to Hollow Revolving Centre?

[I_wanna_Shed]

Hi All,

In the March edition of Woodturning magazine, they are making a lamp base which I would like to add to my list of projects. However, I'm not sure how to drill the hole up the length of the base (approx 22cm).

They use a Hollow Revolving Centre. I gather this is like a dead centre which uses a drill bit as its initial 'point', and you wind the tail stock to drill the timber. Is this right? They also use a spur drive with a spigot - which I can see on the CWS website.

Is there any other way I can drill a dead straight and dead centre hole, without having to purchase a hollow revolving centre (I can't find one on the net, so maybe they are pricey?).

Thanks for the advice,
Nathan.

[DJ’s Timber]

Jim from CWS sells one (http://cws-store.yahoostore.com.au/cgi/index.cgi/shopfront/view_product_details?category_id=1107144940&product_id=1107452334) and yes they are pricey but not much more than a good quality live centre

[joe greiner]

The centre hole doesn't need to be dead straight or dead centre. You can drill from each end with the piece off the lathe, slightly more than halfway so that the two holes meet with sufficient space for the wire; may need to drill about 3/4 of the length from each end to achieve this. The drill bit itself may be somewhat dear, no matter how it's used. Does the article indicate a full-length pipe for the wire? Not necessary IMHO; use about 80mm to adequately secure the lamp socket.

Joe

[Gene45]

Hi All,

In the March edition of Woodturning magazine, they are making a lamp base which I would like to add to my list of projects. However, I'm not sure how to drill the hole up the length of the base (approx 22cm).

They use a Hollow Revolving Centre. I gather this is like a dead centre which uses a drill bit as its initial 'point', and you wind the tail stock to drill the timber. Is this right? They also use a spur drive with a spigot - which I can see on the CWS website.

Is there any other way I can drill a dead straight and dead centre hole, without having to purchase a hollow revolving centre (I can't find one on the net, so maybe they are pricey?).

Thanks for the advice,
Nathan.
For making a peppermill, (12" high) I drilled a straight hole though the wood, made wooden blanks to fit the holes, then put the whole thing, with the blanks, in the lathe and turned the mill. The outside is then directly around the hole. I needed a 1 3/4" hole in one end and 1" in the other.

[Jim Carroll]

Nathan depending on how long the lamp is you may be able to drill all the way through or half way then invert.

If it is say 250mm total lenght then put the tenon you have on the end of the blank in your pin jaws. Use the revolving live centre that has a removable pin and a space for the shavings to drop out and the long hole boring drill bit. Put the drill through the tailstock then through the live centre up to the wood, put your fingers on the drill bit so they are touching the rear of the tailstock, move them back about 1" then push the drill in till your fingers touch the tailstock. Remove the drill till the shavings come out the live centre hole. Then keep doing this till the drill goes through to the other end, progress slowly so you do not clog the drill bit and also gives the drill bit a chance to go straight.

When you do a longer lamp you will only be able to go so far with the drill bit this is where you invert it around and use the drive spur with the spigots to line up with the hole you have already drilled then do much the same till you get through to the hole from the other end.

So in essence to do lamps you need a long hole drill, Boring live centre and the spur drive with spigots, may sound expensive at first but they are a once of buy as the will all last a very long time.

Forgot to add run the lathe at about 300rpm so you do not generate too much heat on the long drill, the last thing you want is to break it of down the hole as there is no way to get it back out, talking from experiance.:C

[I_wanna_Shed]

Thanks for the replies everyone. I think I will hold out making the lamp/s until I get the right gear.

Thanks Jim, I'll come to you when it comes time to buy.

Cheers,
Nathan.

[DavidG]

What about running the wood length wise through the bandsaw.

Routing a channel in each side then gluing the bits back together.

[OGYT]

I bought an Electrician's 9/16" drill bit. It's the kind of bit used to drill through walls; it has a hole in the business end, to attach a wire to and pull it back through the hole in the wall. The bit is 20 or so inches long, and cost about $30 USD. They should have those in Oz.
All it takes is drilling the hole through the blank, and then mount the blank centered on the hole. That way, when turned, the hole is through the center.
Should I add, that I've never used it yet??? Got busy learning how to chase threads, and forgot about the lamps. :D