Spur drive into hard(er) timber?

[Mr Brush]

Excuse the silly question - all this woodturning stuff is still a bit new to me.

Until recently I've only used/practised using relatively soft timbers, but am now starting to use spotted gum, brushbox, etc. to make tool handles and so on.

The JET spur drive that came with my lathe goes into softer wood with just a centre-punched hole to locate the point, but with harder timbers I'm having trouble getting enough purchase for the spurs to engage the wood reliably. I appreciate the need to remove the spur drive from the lathe before giving it a good tap into the end of the wood using a rubber mallet, but even that doesn't get me very far with spotted gum.

I've attached some photos of the spur drive head.

Now, since the width of the centre point in the plane of the spurs is 3.2mm, is there anything wrong with drilling a slightly undersize hole in the end of the timber (e.g. 3mm), then the wood won't have to be compressed too much by the point when driving the spurs in?

Also, is there anything to be gained by sharpening the spurs themselves a bit? By this I mean removing material from the trailing edge of the spur to assist in penetrating harder timber.

Or is the answer (c) none of the above????

Any guidance much appreciated.

Cheers

[Pat]

I use the Vicmarc Drive dog Punch. No damage to the Spur drive. I use it with Jet, Teknatool, Woodfast and no name spur drives.

[wheelinround]

Use the BS and cut an X or + across centre giving the spurdrive a good grip not to deep just a nick

[Mr Brush]

I think I posted just as the forum went down for maintenance......here are the pics I mentioned

[Nai84]

Hey Mr Bush

Well I dont have a bandsaw as of yet so when using really hard wood like bush jarrah I mark and X or + on the blanks and using my lovely drill I drill a hole in the center about 5mm is what I use so the pointy bit of the spur drive goes in nice and snug and they I give it a good couple of bashes with the mallet and that seems to work for me on hard woods just have a play around and see what works for you all the best

Ian

[Mr Brush]

Thanks guys - I'll try the bandsaw first, as I won't have to buy anything.

Failing that, the Vicmark punch thingy after Xmas.

Is there anything fundamentally wrong with the method I was proposing (i.e. drill shallow 3mm hole in centre)??

Cheers

[Mr Brush]

Thanks Ian

OK - tomorrow I'll try the 3mm hole in centre combined with X cut using the bandsaw. Has to be better than what I'm doing now !!

[Nai84]

My spur drive point is tab bigger then that one so made a 3mm drill bit would be best for your one good luck

Ian

[Nai84]

No worries mate I just glad that I can finaly give back to someone for a change

[Skew ChiDAMN!!]

If you take the time to draw an X on the end for centering, then a quick punch in the centre with a centre-punch, blunt nail or similar doesn't hurt. I have a cheap old drive spur that I sharpen for just this use.

(I wouldn't recommend using a "good" drive spur this way though... it tends to screw up the MT.)

[TTIT]

Thanks guys - I'll try the bandsaw first, as I won't have to buy anything.

Failing that, the Vicmark punch thingy after Xmas.

Is there anything fundamentally wrong with the method I was proposing (i.e. drill shallow 3mm hole in centre)??

Cheers

The bandsaw cross is definitely a go'er but I reckon the Vicmark punch is a waste of money - you can buy another drive dog for $20 or $30 less and reserve it for punch use only to get the same result.
If you're a little bit handy with metal, my best solution was to spring-load the centre-point in my drive dog - easy to line-up and positive grip everytime - no bandsawing, punching, nothing

[jefferson]

IMO the best option is a Sorby steb centre. These grip just about anything. Just wind the tailstock up and away you go.

[Jim Carroll]

Use a wooden mallet not a rubber one as that is a waste of time. If anyy harder then a mash hammer works really good. this is where the vicmarc drive centre or a spare spur drive work best. If you are not getting the right grip you are not hitting hard enough.

It is better to get a good purchase with the spurs of the drive centre, the problem with the bandsaw way is that the spurs are sitting in grooves and not really digging into the timber for a solid grip.

Jeff you have to be carefull with the steb centres on really hard timber as sometimes they do not produce enough grip especially if they are long peices which can twist easily.

[rsser]

Mr B., you could also try this and it follows from Jim's advice ...

Just tap your spur drive in a bit and then remove.

Then mount the piece vertically in your vise and put a couple of light handsaw cuts at right angles aligned with the spur marks. A fine tooth saw is the one to use. Tenon, dovetail, gentleman's ... whatever you've got.

Then use a wood mallet to hammer the drive dog back in.

[Mr Brush]

Ahhhh....great minds and all that !!

I tried this today; got as far as drawing diagonals on the timber to find the centre, then found myself wondering how to hold the workpiece to cut grooves on the bandsaw

Rapidly concluded that a handsaw would be easier, plus the kerf almost exactly suits the width of the spurs. A few minutes with the 20tpi Veritas dovetail saw, a shallow 3mm hole drilled in the centre, and I finally get a good reliable purchase with the spur drive.

Problem solved !

Thanks to all for the suggestions - I couldn't believe that I was the only person having this problem. Unfortunately this wasn't covered on my "Introduction to The Spinside"" course at Trend Timbers, where we only used fairly soft and friendly timbers for spindle practice.