DVR mounted and turning!!

[Stu Ablett in Tokyo Japan]

OK, I got the DVR mounted up, finally!

I had to wait to get the 1/2" thick plate for the mounts, but I got it done!

41301
You can see that I want this to be fairly solid

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1/2" plate welded to the I-beam
frame should be somewhat solid..... ;)
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I even used the extra holes on the headstock end so I have 8 bolts holding the DVR down.

[Stu Ablett in Tokyo Japan]

OK, now that I've shown you that the DVR is mounted up nice and solid, I'll show you a problem I'm having........

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41305

On the inside and the outside, unreal!

The tools are sharp, just got them off the grinder, I notice that for about 30 seconds it cuts OK, not great, but OK, then, massive chatter.

This wood is the Red Keyaki and it is freaking hard stuff

anyone with any suggestions to help me get rid of this, please speak up!

Cheers!

[Gary DeWitt]

Tough question without being there to see and hear what's going on.
Here's some things you can check:
Ensure full contact between your chuck and the tennon, both around the inside of the jaws and between the top of the jaws and the bottom of your bowl.
How thick is the bowl now, is it already turned or nearly done on the inside? Thin unsupported wood will vibrate. The furthur from the chuck, the greater the vibration. Consider what happens when you "ring" a crystal wine glass with the friction of a finger. Same thing, only much bigger oscilations. Sometimes using a different speed, or a different tool, or just a lighter touch will help.
That looks like a new lathe, so I doubt there's any slop in the bearings, but it wouldn't hurt to check for side play.
If none of the above helps, maybe you could take a pic or two showing your tool presentation in contact with the bowl (with the lathe off), and draw a pencil arrow on the bowl showing direction of tool travel.
Hope this helped.

[Stu Ablett in Tokyo Japan]

Thanks for the input Gary, I'll try to take a video of me turning it.

The wood is VERY hard, and it does vibrate, it is so hard now that is almost rings when you hit it hard, like a bell.

I'm going to try some of the Sakura I have and see if there is a diff.

Everything else you mentioned check out OK.

Maybe I need to build one of them steady rests...........? :D

http://www.woodcraft.com/images/Family/web4391.jpg

Cheers!

[Vaughn McMillan]

...Maybe I need to build one of them steady rests...........? :D I dunno, Stu...are you sure you could build something like that? Seeing as how you aren't very inventive or handy with the welder or anything like that. :rolleyes: :D (You'd probably have one built and running before most of us could find the parts.)

Congrats on getting the new spinner spinning, too.

- Vaughn

[Raymond Overman]

Stu,

Just making a guess so take what you can out of this.

1st, when you make the final sweeps on the bottom of the bowl do you have the tailstock in place to stabilize the blank? If not, try it and see if that helps.

2nd, make your tenon as large as your chuck jaws can handle. The smaller tenon may allow more movement when you are pushing against the outside edge of the bowl. You have a lot of mechanical advantage out there and the angle of pressure at the tenon has changed when you are cutting the rim of the bowl.

3rd, once you've turned the bowl around and put it in the chuck consider keeping the tailstock in place as long as possible and making cuts at the rim of the bowl inward so that you have more mass to dampen vibrations. I even use a boring bar sometimes to get the meat of the bowl out while working around a cone shaped piece in the center with the tailstock pulled up.

Just a few thoughts. They may not relate. Good luck.

[Stu Ablett in Tokyo Japan]

Thanks Raymond, all great tips!

Vaughn......who me....? :D

[Rich Stewart]

Don't know if tis has anything to do with anything Stu. Is it with just one tool that it does that? I have one tool that came in my original set that i can't do a thing with. As soon as i touch the wood with it, it bounces all over, tears up the wood, tries to fly out of my hand. My solution? I never touch that tool now. It looks similar to my roughing gouge that i use on everything.

[tod evans]

stu, it`s that darn flimsy stand you`ve got the lathe mounted to.
dare i say try a scraper? i may be booted for such blasphmey. when stuff gets to chattering on me i try a different presentation angle and if that doesn`t cut it straight to the scraper...02 tod

[Keith Burns]

Stu, great looking set up ! I'll offer my opinion which probably isn't worth much. Doesn't look like a vibration/chatter thing to me. Why ? Because the marks don't appear to go all the way aroung the bowl. My guess would be that your chuck may not have been tight and you had a catch which pulled it partially out of the chuck which basically made your bowl out of round. Thats why the marks are heavy and only in one area. Now that I've totally confused myself......................

[Stu Ablett in Tokyo Japan]

Rich, it does it with the two bowl gouges, and both scrapers I have, I think it is just really, really hard wood.

Tod, sorry about the flimsy stand, I know I let you down.... ;) :D

Keith, I don't remember having a catch.........?

I checked to see if the chuck was tight, and it seems to be, I just really think that it is the wood, I'll try something else tomorrow.

Thanks for all the thoughts and advice guys!

Cheers!

[Sparky Paessler]

Now I see why the price of metal is so high here. They have been sending it all to Japan! Looks great Stu. Sounds like Keith is on the right track for your problem.

Sparky

[Stu Ablett in Tokyo Japan]

Oh, I forgot to mention, the marks go all the way round, just the last inch or so of the bowl, you can only see the marks in one spot, because of the way I have the light shining on it, to show the marks.

Cheers!

[Jim Becker]

Stout stand and mount, there Stu! And you even have enough room to add another bed extension someday if you want to get into long spindles!

-
That chatter is nasty. Assuming nothing is loose or otherwise out of kilter (be sure that the insert in the chuck is seated square) a steady will help, but technique is also important. Your outside should be pretty much to shape and "finished off" other than in the foot area before you start hollowing, even with a roughed piece. You do NOT want to have to revisit the outside, especially near the rim, if you can avoid it.

When you hollow, it's often best to "step" the bowl once you have it roughed out. That means you get rid of most of the discard, but leave things relatively thick compared to your intended final wall thickness. They you start at the rim and bring the first inch or so to final thickness. You then bring the next 1" "step" to final thickness, making every effort to avoid revising that first "step". (A steady is still very helpful for thin piece and certain species that tend to uneven densities and chatter because of it) Once you have the whole thing hollowed to final thickness, if you need to clean it up, slow the lathe down and use a VERY sharp scraper held in a shear-cut position or a side-grind gouge to do a final finishing cut, supporting the outside of the piece with one hand or with the steady. (Scraper is inside-out with an extremely light touch and the side-grind gouge is outside-in with the flute pretty much just a hair above horizontal for a tiny, tiny cut)

[Dick Strauss]

Stu,
You don't tell us if you have already hollowed the inside or not. Were you making the cut with the cutting edge of the gouge pointing tangential or radially out from the piece?

The only time I've had that problem was with dry wood when I didn't rub the bevel properly or the tool was a little dull. Try taking your bowl gouge (sharpened with a nice burr edge) and rotate the bottom cutting edge so that the cutting edge is actually scraping the piece from the side (the cutting edge is facing radially inward). Try scraping back and forth to smooth that area out.

If that doesn't work, check the height of the tool rest. The cutting edge should be roughly at the center height at all times. This means that you'll want to lower the rest for thick scrapers, etc. Tool rest height can cause problems simialr to what you show as well.

I guess there are too many possiblities unless you give us more detail...

[Stu Ablett in Tokyo Japan]

Dick and Jim, thanks for the pointers, I'll try these out.

The inside was roughed out, but not finished.

I did the shear scrape like Bill G shows in his DVD, it was better, but still I got a lot of chatter.

The tool was sharp.

I'll give it some more work and try to take some more pics tomorrow, thanks for the help, one of the many reasons I love this place.

Cheers!

[Charlie Plesums]

Right after I got my DVR a neighbor appeared in the shop (aka Garage) door, and said, I've got two lathes... One is a funny yellow one, and the other a mini. Like a guardian angel he appears whenever I have a problem... and you have a good representation of one of my problems.

The issue, as several people have noted, is vibration.

His first recommendation is to start at the outside edge... get the lip/rim turned before the bowl is completely hollow, so that you have more mass to support the rim and to dampen vibrations.

Make sure your toolrest is close, and you use your heaviest tools. I can guarantee chatter with my small spindle gouge (in fact I saw one turned do it intentionally for a decorative effect). If I start to get it, I go to the largest tool that works, from as close as possible, sometimes putting the end of the bowl rest well inside the bowl.

Put your hand against the outside when turning inside, and vice versa. If your hand gets too hot, you are pushing too hard. If you need to push that hard with your hand, you are pushing too hard with your chisel.

Once you get chatter, it is extremely hard to get rid of it. If I have enough thickness, I usually just cut away the entire layer, riding the bevel of a bowl gouge on fresh wood, perhaps with my hand on the other side to dampen any vibrations that might think of reappearing.

My guardian angel is down on steady rests... says they introduce too much torque... believes in the hand as the steady.

Incidentally, I cheat. I wear a leather glove on my left hand when I am turning. The Charlie derivative of the Grumbine technique shoots the chips directly at my hand... they are hot and abrasive, but the glove doesn't care (and it beats shooting the chips at my face or neck). So it is often a gloved hand that stabilizes the bowl or spindle... but no harder than I would do it without the glove.

[Frank Fusco]

Fine mounting job on that lathe. I'm sure you are not looking down the road to when that rig has to come OUT of the dungeon. :eek:
Can't add to the turning problem, except to suggest trying it on a $400.00 Grizzly. ;)

[Ernie Nyvall]

I can't add to the suggestions on the cause of vibration, but CONGRATULATIONS on getting that thing in and set up. Way to go Stu!!!

Ernie

[Dennis Peacock]

Congrats Stu on the new lathe and the stand looks nice and beefy!!!!!

BTW, You have a package headed your way. :eek: :D :D

[CPeter James]

Stu, Do you have a good high speed Internet connection? If you do, I can send you some excellent articles on turning tools and sharpening. They are in our Guild newsletter.

CPeter

[Stu Ablett in Tokyo Japan]

Congrats Stu on the new lathe and the stand looks nice and beefy!!!!!

BTW, You have a package headed your way. :eek: :D :D

Thanks Bernie!

I hope the stand works well, I cannot add an extention, as I do not have enough space, I'd have to move the whole unit out about one foot, I could do that if I wanted to.

Cheers!

[Stu Ablett in Tokyo Japan]

Stu, Do you have a good high speed Internet connection? If you do, I can send you some excellent articles on turning tools and sharpening. They are in our Guild newsletter.

CPeter

CPJ, thanks for the offer, I'll send you a PM.

Cheers!

[Mike Ramsey]

Great job Stu! looks like it could hold up a Locomotive! A fellow club
member asked me if I knew anyone with a Nova...I emailed him
a link to your posts..... purchase is pending!!

[Stu Ablett in Tokyo Japan]

Well, so far the Nova DVR-3000 is great, and I expect it to get a lot of work!

Cheers!

[Dennis Peacock]

Thanks Bernie!

I hope the stand works well, I cannot add an extention, as I do not have enough space, I'd have to move the whole unit out about one foot, I could do that if I wanted to.

Cheers!

"Bernie?"??????

Hey Stu....you been drinking and typing again??:rolleyes: :p

[Stu Ablett in Tokyo Japan]

"Bernie?"??????

Hey Stu....you been drinking and typing again??:rolleyes: :p

Whoops.......:o

No, I wish I was drinking and typing, just working too darn much!

Thanks DENNIS!!!

[Stu Ablett in Tokyo Japan]

Well you can see the results of this effort here.....

The Wave (http://www.sawmillcreek.org/showthread.php?p=384982#post384982)

Cheers!

[Charlie Plesums]

Great job Stu! looks like it could hold up a Locomotive! A fellow club
member asked me if I knew anyone with a Nova...I emailed him
a link to your posts..... purchase is pending!!
It is a long way to Austin, but not as far as Tokyo. I would be glad to show off my DVR