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Dewey Torres
01-29-2009, 8:36 PM
I can't for the life of me figure out why the spur will not grip. Even when I turned my bonker with a piece of pine I ran into the same thing with the roughing gouge where I could stop the piece with it. I am not forcing anything the spur just insn't gripping.

Help:o

David Christopher
01-29-2009, 8:42 PM
Dewey, a few things. is it on the bark side ( remove bark )
did you take a mallet and tap it into place ( if not, do so )
and if it is soft wood it can just be a PITA

Don Carter
01-29-2009, 8:46 PM
Dewey:
You can cut grooves in the end of your spindle blank on bandsaw that your spur will fit in. Or, and I hate to take you down the road of buying more stuff, but I like to use this drive center for spindle blanks:
http://www.pennstateind.com/store/LCENTSS22.html
More stuff...:rolleyes:

All the best.

Don

Dewey Torres
01-29-2009, 8:49 PM
Dave,
Forgive me I am a newbie...second turning AAMOF.

No it's just a small piece of kiln dried walnut see pics.

Bob Hallowell
01-29-2009, 8:49 PM
use a wooden mallet to set it into the wood first.

David Christopher
01-29-2009, 8:52 PM
what Bob said, take a mallet and tap the spur into the wood deep enough for it to hold

Dewey Torres
01-29-2009, 8:54 PM
Dewey:
You can cut grooves in the end of your spindle blank on bandsaw that your spur will fit in. Or, and I hate to take you down the road of buying more stuff, but I like to use this drive center for spindle blanks:
http://www.pennstateind.com/store/LCENTSS22.html
More stuff...:rolleyes:

All the best.

Don

Don,
I do not at all mind spending money...whatever the cost to make my life easy and turning enjoyable. I have been doing flatwork since I was a kid and I am on a current crusade to rid myself of tools that don't perform. I may just go ahead and place the order now.
In the meantime I just cut a slit or 2 with the BS where the spurs make contact right?

Don Carter
01-29-2009, 9:02 PM
Dewey:
Short answer is yes. In kiln dried wood, I have split the wood pounding the spur into it. You can cut the grooves to fit the spur in the end so the spur gets a bite. If the wood is softer I have "tapped" the spur in with a mallet. But I really like these drives, the center is spring loaded and will recess as tailstock pressure is applied until the teeth bite.:)

All the best.

Don

Dave Halter
01-29-2009, 9:06 PM
It definitely looks like you need to malletize the spur drive to set it in the wood. As stated previously you can make an "X" in the end with your bandsaw and tap the drive in so that the spurs are in the kerfs.

Dave

ROY DICK
01-29-2009, 9:21 PM
Lock the tail stock and tighten the spindle as needed to prevent slipage. Adjust tool rest to work for you.

Dewey Torres
01-29-2009, 9:34 PM
ok,
Thanks all. Going back to the shop to give it a try:D

Jim Becker
01-29-2009, 9:58 PM
Well, you could use a mallet, but you could also put one of your new bonkers to work getting that spur seated! LOL

Allen Neighbors
01-29-2009, 10:10 PM
I used a dremel tool with cutoff blade and re-shaped the end of mine, so it would grip better.
It also can help to drill a short hole for the point to set into when you tap the spur drive.

Bernie Weishapl
01-29-2009, 10:42 PM
I drill a small hole in the center and cut slots on the bandsaw. If it is soft wood well light cuts and keep the tailstock tight.

Joe Chritz
01-29-2009, 10:50 PM
I just turned my first bowl shaped object this morning and I have similar problems whenever I had one of many catches. This turning thing isn't as easy as it looks.

I have a vicmark chuck so I switched to the screw chuck and problem solved.

Joe

Gordon Seto
01-29-2009, 10:51 PM
Do you have sharp tools? From the shaving in your picture, it seems the wood was not being cut efficiently.
On spindles, I don't even use a spur drive. I just use a safe drive; the pressure from the tailstock would generate enough friction for the dead center to drive the spindle.
The picture shows the prongs have sunk into the wood lightly. It should be enough to drive the spindle of this size. It is safer to have the spindle slip than the blank fly off the lathe if something goes wrong.

Curt Fuller
01-29-2009, 10:58 PM
Also, besides all the good spur seating advice, what speed are you turning? For a spindle that small you can easily (and safely) turn at 2000+ rpms. That gives you less air time in between the gouge making contact with the wood until it gets round. When you're not used to the lathe the speed seems fast, but it actually is better on small diameter pieces. It also might be the way you're presenting the gouge to the wood. Make sure you have the tool rest just slightly below the center of the wood. Keep the handle down (lower than the rest) and slowly raise it until it begins to cut (riding the bevel concept). When I was first turning I had a tendency to scrape with the roughing gouge by keeping the handle level with the rest. That puts a lot more bite into the tool and graps the wood, making the spur strip out. Think of it as sharpening a pencil with a pocket knife, only the pocket knife is the gouge and the pencil is spinning. You just want to take a light, gentle cut, cutting from the the larger diameter towards the smaller. If you stop the lathe and try to carve with the gouge you can see the angle that the tool needs to be to cut smoothly. Then it works the same way with the wood spinning.
Hope that helps. (and makes sense)

Steve Schlumpf
01-29-2009, 11:44 PM
Dewey - hope by now you have it all figured out! Only other suggestion would be to place your tool rest closer to the turning - say 1/8" to 1/4". The rest offers support to the tool and the more the tool hangs over the rest - the more likely you are to get a catch.

Looking forward to finding out what you did to correct the slipping problem!

Scott Conners
01-29-2009, 11:50 PM
Firstly, if your spur is like my Jet one when I got it, it needs sharpening! I took my grinder (carefully!) and a file to mine until it was almost knife sharp, and it helped a lot.

I really really love my PSI steb centers like Don posted, I've permanently retired my 4 prong center in favor of the set of small and large centers. I bought mine off amazon for the best price.

Mike Lipke
01-30-2009, 12:03 AM
A lot of turners think that the 2 spur drive grips a lot better than the 4 spur drive. I had 2 four spur drives, and I took one and ground 2 spurs off to make it a 2 spur drive. It works much better.

Narayan Nayar
01-30-2009, 12:43 AM
Hey Dewey. Like you, I'm just getting started with this whole turning thing. I had the same problem. Here's what I've done--

As someone mentioned, take a file to the spurs. They don't need to be plane-blade sharp, but sharpening will help a lot.

I bought my current lathe second hand and it didn't have a spur, so I had to buy a third party one. The one I ended up with has a spring in the center, which helps (it compresses so the wood ends up on the spurs, and not just on the center. FWIW, it's a 4-spur one.

Lastly, I just use an awl or a nail punch to create enough of a dent in the wood. Gets the center started and is easier to position as you bring up the tailstock and tighten everything up.

Jim Becker
01-30-2009, 10:32 AM
Mike, I use a 2 spur for odd-shaped surfaces, such as putting a rough hunk of wood between centers to discover what the actual orientation will be, but I don't see any advantage for spindles that have a regular surface on the end. It may have less grip, although it would certainly be easier to seat in something hard since you're only wacking in two spurs, instead of four.

George Clark
01-30-2009, 11:03 AM
Dewey,

As a new turner, the Oneway Safe Driver was recommended to me and I would pass that recommendation along to you. When using it and the wood slips I need to tighten the tail stock a bit and/or alter my tool presentation. It is designed to allow the wood to slip with improper tool presentation, thus preventing or minimizing disastrous catches. I also use a spring loaded center punch to mark the center of the spindle and provide a starting point for the pin. Since obtaining the safety drive I have not had my spur drive out of the drawer.

http://www.oneway.ca/spindle/safe_drivers.htm

George

Paul Atkins
01-30-2009, 1:52 PM
George got it right. I tossed my spur centers 20 years ago and haven't looked back. If a spur center slips, you risk throwing the piece off the lathe, ruining the end and will never get the thing centered again. If these centers slip -so what? Just tighten them a bit. I made these centers over the years and have turned hundreds of 1/4" spindles to 9' x 8" porch posts with these and have not had a problem. I made the drive center and the live center the same size so I can flip the piece end for end and it still stays centered -sometimes I don't even turn the lathe off. One piece I make for production is turned 2" on each end but not in the center, so I leave the tool rest in place. Time saver. I've never used the toothed centers or the 'safe centers ' but the idea is the same.

Dennis Peacock
01-30-2009, 7:48 PM
Well Dewey.....???? How ya coming on the spur spin deal??? Inquiring minds wanna know.....ya know. :D

Dewey Torres
01-30-2009, 9:28 PM
I just cut the cross hatch into the end with a saw like suggested earlier and will likely get that PSI spur with all the teeth and give it a try.

Wally Dickerman
01-30-2009, 10:27 PM
If possible, make cuts with the bandsaw as others have said. After seating the spur drive, remove it and apply some thin CA glue to really firm up the wood. That should take care of your problem. It does for me.

Wally

Dewey Torres
01-30-2009, 11:22 PM
If possible, make cuts with the bandsaw as others have said. After seating the spur drive, remove it and apply some thin CA glue to really firm up the wood. That should take care of your problem. It does for me.

Wally

It has for me as well Wally but I don't favor the idea of performing that function for every spindle I turn. Call me lazy but for me it is really about more efficient shop time.

robert hainstock
01-31-2009, 8:37 AM
What they said and I use a sixteen oz. plastic tipped mallet for seating my spur, use lots of pressure on the tailstock, and still have teasout occasionaly. If trning a spindle, too much pressure on the taialstock can bend the spindle so it is a fine line. Good luck! And AA. :)
Bob

Dean Thomas
01-31-2009, 2:17 PM
I don't agree with the use of the Steb center clone. When that puppy spins (and it will; go ahead ask my how I know!), instead of the nice little rub mark you got from your spur drive, you'll get a trough! Tighten it down some more and you'll dig deeper and continue to do so until the wood reaches the bottom of the space between teeth and center point!

The Safe Drive from Oneway is really nothing more than a dead center with a spring loaded center pin. The nice thing about this is that if you get a catch, the wood simply stops spinning. If you're on top of things, you have the option of shutting off the lathe to investigate the cause of the catch. It's a great tool for learning new tools, especially that scary skew, and really great for teaching kids to use the lathe. To use the SD or even an old dead center, drill a hole in the end, use an awl to shape that hole to the profile of the pin in your center and use the tail stock to press the rim into the grain.

BTW, from your picture, Dewey, it really looks as though you did not have the spur side of the wood at 90º to the spinning axis. If the wood surface at the spur is not square, you have to do something to ensure that you engage all of the spurs. I have a friend who gently engages a Forstner that is about the same diameter as his spur to make a place for seating. The dent left from the pilot on the Forstner makes a pretty good starter for the pin on his spur drive.