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View Full Version : Tapering(?) a long bit of dowel



kentsusai
23rd June 2004, 12:29 PM
Hi folks,

I have a 9ft length of dowel. It is 30mm in diameter. What I need is for the last 4ft to be tapered(?). What I mean by tapered is that it gradually gets thinner and thinner as it gets towards the end. At the end it has to be 26mm in diameter.

The piece is a bit too long for my lathe, and I cannot cut it. If I could cut it, it would be very easy to do. Any alternatives or solutions other than buying a bigger lathe?

Many thanks in advance!!
Chris

Kev Y.
23rd June 2004, 12:40 PM
Does your lathe have a morse taper spindle in the head stock???

If so you could always feed the dowel through the headstock and then the centre of your chuck, to the tailstock. that way you can make sure the dowel is centred and "maybe" running true.

Kev

PaulS
23rd June 2004, 01:31 PM
Chris

I reckon is your man check this out

http://www.ubeaut.com.au/woodstuf.htm
He is the moderator of this part of the forum...

Since you only need to take off 4mm, what about sand paper???

Out of interest, what are you making??

Paul

kentsusai
23rd June 2004, 02:01 PM
Paul & Kev

Thanks for the quick reply guys!

Anyway, I was thinking of sanding it as well. But the guy who wants this done wants about 20 of them. And the taper is about 4ft long.

What he wants made is a japanese spear for his martial arts club. But the end is meant to be tapered, as I described, so that they can fit their funny little attachments on the end. The annoying thing is that they want it in one piece, otherwise it would be dead easy!

By the way Kev, you mentioned Morse tapers. I am not entirely familiar with them. What is it meant to do exactly? (Sorry if it is a dumb question)

Many thanks again,
Chris

Kev Y.
23rd June 2004, 04:07 PM
Morse taper refers to the shape/profile of the spindle on any attachment or chuck ( have a look at the chuck on a drill press ). Most lathes will (or may) have the headstock spinde bored out to accomodate the fiting of various accessories.

The "standard" morse taper is the number 2 morse taper or as it is refered to a #2 mt.

Kev

arose62
23rd June 2004, 04:25 PM
What about an approach like rod-makers use??

http://www.thomaspenrose.com/tonkin.htm

He's planing strips, but you could use the same sort of idea...

Make a jig which exposes the wood to be removed, and plane and rotate a bit, plane and rotate a bit, etc. etc.

I can imagine a couple of bits of wood 4 ft long, a couple of end pieces, one with a 30mm hole, the other with a nail 2mm up from a centre aligned with the centre of the 30mm hole, and let the plane ride on top.

Cheers,
Andrew

RETIRED
23rd June 2004, 08:44 PM
Gooday.

Making Kensai sticks on a short lathe is fun (NOT).

To Kev: very few lathes have a hollow spindle bigger than 20mm so unfortunately can't do it that way but good thought.

To Andrew: Kensai sticks have to be made in one piece otherwise their intregrity is compromised. Another good idea though.

To Chris: How long is your lathe and do you have 2 of them? When I know the answer I MAY be able to help you. Also where in OZ are you?

bitingmidge
23rd June 2004, 08:56 PM
It is not a big job to hand taper as anyone who has made a spar for a boat or a paddle shaft can confirm.

It is a bit tricky starting with a dowel, but if you start by planing the taper on four opposite sides to obtain a square, then on each of the four corners to eight-side the taper, at the diameter you are working you will need very little work to complete the "rounding", one or two passes of a hand plane and a bit of sandpaper work.

Woodenboat Magazine issue #176 (Jan-Feb this year) had an article on building a simple shop-built spar lathe, but for the number you are after you could probably have the job finished in the time it took to build the lathe!

Back issues of the Magazine are available through Boat Books (http://www.boatbooks-aust.com.au/) in Brisbane Sydney or Melbourne.

Cheers,

P

kentsusai
24th June 2004, 12:20 PM
Thanks for all the ideas guys!! Much appreciated!

At the moment, I was thinking of making something as Andrew suggested. I'll give it a shot. Will be a bit tricky as the angle is a bit steep.

Btw , I only have one lathe. When I put the wood in through the chuck I have about 4ft exposed. The rest of the dowel sticks out and wobbles like crazy when I put it in there. I don't have any way of supporting it. So... probably the lathe isn't the way to go.

Oh and I live in Melbourne.

Thanks again guys

Jigsaw
25th June 2004, 09:23 AM
I would making up a jig that supports the last 4 foot of dowel and above this have a jig to support a router. The jig would be made with so the router just slides along for the 4 feet but made to include the taper required. Rotate the dowel by hand preferably someone elses. One person controlling the router and another turning the dowel.

esiegel
26th June 2004, 12:12 AM
Sounds like what you really need is a giant pencil sharpener.
A box with a 4' blade mounted at the correct angle that you could feed the dowel into and turn (by hand?) to shave the taper.

If you have to make enough of these it may be worth build something like this.

RETIRED
26th June 2004, 09:13 AM
Look in private messages Kentusai

Tip hunter
26th June 2004, 09:19 AM
Cut a taper on many sides using a taper jig then roll in front of a disc sander maybe?