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I have a 4 prong spur center that is difficult to get a bite on really hard woods. I don't want to pound it into my blanks, with fear of splitting the wood. Sometimes I can make 4 divots with a 1/2" chisel to give the spur blades something to dig into, but even that risks splitting the blank. How do you guys handle this?
 

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My NOVA DVR lathe came with a 4 prong drive centre with a fixed centre point. Not easy to force into some dense woods, but I was not worried about splitting the blank.

These days I use 4 prong drive centre with a spring loaded centre point. This is my Oneway version.

http://www.packardwoodworks.com/Mer...33&Category_Code=lathes-acc-fourjaw-1ow-talon

With this version I make a small point with a spring loaded centre punch and then use tailstock pressure to engage the prongs.

I am not trying to get the prongs deep. If I get a catch, I like the wood to spin. I then re-engage the prongs as needed.

If you have a spring loaded point, your work process to use a chisel to create the marks for the prongs ought to work.
 

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I don't know that much about turning and lathes. I have one and have had to use it for various projects. It only came with a spur bit. I would be hesitant to close up the tail piece to get a bite. I just punched a center hole with a scratch awl.

My spur bit is threaded on, and I have removed it and used it loose to tap an impression. But it seems to get a bite with just a center punch hole in both ends of the stock.






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You make two cuts in the end of your work piece with a bandsaw or handsaw, corner to corner, 1/4" +- deep. You will split the work if you drive the spurs in. With the cuts you only need a small tap to get a good grab.
 

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I have never split a piece but in hard wood I cut a notch for good transfer of power, an 1/8" + deep should be enough. Note the wings on your spur, one side is flat to provide the power. Cut straight down like l/ and take out the chip with a second cut leaving the one side flat. If you cut a V the spur can ride out if it gets loose at all. This would be for a platter, bowl, etc.; for spindle work cut an X with a saw. You can also file/grind the spurs for good sharpness and they are much easier to seat with a mallet.

These days I use a steb center for hard wood and it holds tight without any setting to speak of.
 

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Discussion Starter #8
I have never split a piece but in hard wood I cut a notch for good transfer of power, an 1/8" + deep should be enough. Note the wings on your spur, one side is flat to provide the power. Cut straight down like l/ and take out the chip with a second cut leaving the one side flat. If you cut a V the spur can ride out if it gets loose at all.
Yeah I'm aware of keeping one side flat. The spurs on my old Oliver drive center are also offset from center a bit so they don't dig into the same grain lines. An X across the corners would have to be pretty wide. I think I'll keep using the chisel method for now, and invest in a stub center for the future.

Thanks guys.
 

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Unless your getting ready to turn small diameter pieces, atleast on the ends, you shouldn't have any issues with cracking and splitting the wood.

If you do, you might want to chose different piece of wood. Getting hit with chunks flying off your stock hurts!
 
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