Help, keep snapping bottle peices on new lathe!

[Lyle W. Kerr]

:mad:Well I moved up from my dad's old Record Power mini lathe and went for the gusto, a 85 Delta/Rockwell 46-450.

It's big and powerful, full 2HP, did the 3PH 220V converter and everything. Problem is, I haven't been able to make a thing on it with out it breaking off half way through!

The problem seems to be I am catching the piece as I am turning and instead of stopping like the old lathe it just snaps it right off. The last bottle top I was working on, just now, snapped the screw on my screw chuck in half. That was the third chuck! Peices flying and I'm getting scared of this thing.

I am just not sure what I am doing wrong at this point, I have made a decent amount of the bottle toppers on my old lathe, so I thought I had a clue. Now I don't know.

Any help would be greatly appreciated!

[Gary Herrmann]

Lyle, describe your process for us. Material used, how you chuck it, glue used if any, tool used to shape it etc. A pic of one of the broken off pieces will help us diagnose.

Bottle stoppers are spindle turnings. An aggressive cut with a gouge could snap it off pretty easily. How sharp are your tools and are you riding the bevel?

[Steve Schlumpf]

Lyle - sure wouldn't think there would be much of a change when moving from one lathe to another. Without any photos - it is really hard to make any suggestions as to what corrective action for you to take. First question would be about your tool rest height. Then what tool you are using, what wood, etc. If you turned bottle stoppers before but had catches that stopped your lathe - chances are you are doing the same thing again only the new lathe won't stall. So, brings up what tool you are using, height, etc.

[Barry Elder]

I agree with Steve about the catches and stalling a small lathe. The easiest solution would be to find a woodturning club in your area and get someone to mentor you. The problem would probably be solved in less than 30 minutes. Try www.woodturner.org and find a nearby club. Woodturners usually are quick to help out everyone.

[Paul Atkins]

I'd check the height of the tool rest too. If you were used to one and went lower or higher on the new one, your tool angle and stance will have to be different. Is the lathe the same height from the ground? This would be a great place for a video from you if it were possible.

[Lyle W. Kerr]

Tonight when I get home I will see if I can post some pictures and possible video. The only problem is that was my last screw chuck last night and the threads on it are metric. Would love to know a source for 6mm hanger bolts.

FYI, the screw center 29846 is from Sears, it was the same, except for the threads, as my old one, though a #2MT. At $8.99 each you can't go too wrong. I did try another screw center that screws on but the center screw kept coming loose on it.

Off the side note, the Delta 46-450 is higher than my old one that was mounted to my bench and I did notice last night that I did have my tool rest a little high, adjusted it down and continued turning. It was a bit after that wood went flying.

I am running at about 1200RPM, according to the variable speed lever on the front of the unit (63hz on the TECO FM50 3PH converter). The tool last night I was using when this happened was a "Round Nose Scraper". I think that is what it is called. I have had this problem also with other tools. 1/4" gouge especially. That thing just dug right into the wood like a drill bit.

My tools are very sharp, I just sharpened them the other day, this was the first time I have used them since. I have a Tormek wet stone sharping system.

What else . . . oh wood, I have had this problem with maple, green elm and last nights miss hap was with a nice piece of purple heart.

I am a member of the CCW, Central Connecticut Wood Turners, just joined and the meetings are on a bad night for me. I will, how ever, check with them to see if anyone there can help.

Any other suggestions here would be greatly appreciated! :D

[Jeff Nicol]

It all sounds to me is that the screw chuck is not backed up enough to hold he wood you are turning from flexing away from the tool you are using. You have to make sure that the blank is seated against the shoulder of the screw chuck and if you are trying to turn end grain it is the weakest way to use a screw chuck. I have one that I made myself, turned the taper and tapped it for a 1/4" x 20tpi so I can change the type of threaded part sticking out and holding the blank. I use a large fender washer as a backer so that there is some more support for the blank at the end of the screw. Even with all this if the piece you are turning is longer than you need or there is extra length of waste on the blank you should use the tailstock to do most of the turning until it is close to the finishing stages. This will eliminate the flex of the blank and get rid of the undo pressure exerted on the screw. If you are using end grain and need to strengthen the hole for the screw, drop a few drops of thin CA in the hole to strengthen the wood. I think you got away with a lot of the stuff before with the little lathe, but now the big lathe won't be stopped very easy!

Hope this gives you some ideas to remedy the problems,

Jeff

[Reed Gray]

I did run into a guy who was having problems with chess pieces snapping and he thought it was because the wood was green. Turned out he was trying to make them cross grain rather than long grain. Could that by the problem?

robo hippy

[Kyle Iwamoto]

Are you using the tailstock? I use mine as much as possible. Sometimes (most times) I try to part the top off with the TS on. Or what ever you call using the tailstock. I part off with a skew. Probably be hard to do that with a scraper.

[Wally Dickerman]

Unless you are turning side grain stoppers instead of endgrain (grain parallel to the lathe bed) it would be very difficult to pop them off as you describe. Use endgrain only for spindle turnings.

Scrapers are not for spindle turning. Use a spindle gouge, the tool designed for the job. (Forget using a skew until later) Always cut with the grain, (downhill) rub the bevel, and turn with the handle down and cutting above center, and you'll stop getting catches. Bring the tailstock up to support the piece until you are ready to finish off the top of the stopper.

When using the screwchuck that you describe, don't use a tapered wood screw. Use a sheet metal screw, which has harder, deeper threads. Use thin CA glue to harden the screwhole. That will give a better grip on the wood.

Wally

[Lyle W. Kerr]

Ok, so I think I uploaded the pictures. . . .not seeing them here. . .ahhhhh so you need to preview the post.

Ok what we see here is the lathe and the piece I was working on last night. I measured the heights and the old Record Power on the bench was about 40" working height and this one is about 45"s.

I believe that the screw center was screwed into the end grain, but that is how I have done all of the others. This way the grain really shows up when finished. I only highly polish my pieces and put a thin coat of Minwax wax on them. They really shine when I am done with them.

Also in the pictures is the center I have, I would love to find a source for these with a 1/4-20 thread. This is the one from Sears, the problem is that it has 6mm machine thread in it.My old 1MT one had 1/4-20 thread, and looked just like this one. These are under 9 bucks from Sears.

My tool rest is the original Rockwell on this lathe and I run it right at or just below the center of the spindle. I could see the point of higher machine different angle on the tool but does someone have a picture of the correct way on these?

Hold on now, just saw Wally's post. Makes a lot of sense. I could probally get 6mm threaded two sided screws.

Anyway some one could post some examples? End grain etc.

Sorry if I sound a little dumb on the basics, never really paid much attention in school.

[Bernie Weishapl]

Lyle I tried one of those screw center and did have any luck at all with it. I started using the one that came with my chuck and problem was solved for me.

[Dick Sowa]

Lots of good advice. The only thing I can add is that when the tool digs in, and you get a catch, lots of things can happen, really fast. The piece can disintegrate, the tool can break, and you can luck out and be merely left with a divot.

When I am dealing with small, fragile pieces, I spin it very slow...500 rpms or less. And I take light, very light, cuts.

My recommendation, try presenting the tool differently. Take your time, and see what happens.

[Scott Conners]

If you can't get someone to help, you may get a lot of use from seeing a good video. Richard Raffan's "Turning Wood" (plus book the goes with it if you want) or Jimmy Clewes "Back to basics" come to mind. Also Alan Lacer's dvds on skews and turning in general.

[Paul Atkins]

Nice looking lathe. I usually don't use screw centers for spindle stuff because of the problems you are having. I use them for rosettes and short, fat stuff so I have plenty of base support. There is not much support with that small shoulder and a wimpy screw. I would try some pieces between centers to get a sense of what cutting angles and approach to use with a variety of tools without the fear of having the pieces flung at you. Don't think of projects, just shavings and cuts. You also could glue the block on a waste piece and screw it to the faceplate if you don't want to use the tailstock. This would be a bit more secure for the stoppers. I also use collets for stuff like this. The center could be drilled out and re tapped for larger screws too.

[Kyle Iwamoto]

No offense intended, but your design looks like a failure waiting to happen. It is much too thin for all that end grain. If you were to radius the base, I think you'll get much better results. Make the base look like your top. I tried that design too, and had virtually that same blow up......

That screw chuck does look a little wimpy. PSI makes a better one for stoppers.

Just my .02.

[Lyle W. Kerr]

Kyle, what is the one from PSI? Do you have a model number?

I looked at the screw center that came with my Nova @ but the screw is too big for the threaded part of the wine bottle topper pieces I get from Woodcraft.

I don't mind getting a better screw center, Delta used to have a good one I guess, but I can not see spending $100.00 bucks for one. As I said the problem with the Sears one is it is metric, but my old one was great and had a very small face on it, just the right size for the metal piece on the bottle side of the wine bottle stopper.

I guess though I do need to re-think how I make these on the larger lathe though and really need to have someone show me some stuff one on one.

Again any videos or pictures someone can add on here or e-mail me would be great. I do get very little time to go to the barn and practice or time to watch a whole video.

[Kyle Iwamoto]

Get on the PSI site and type in "bottle stopper mandrel". If I knew how to post a link, I would. It comes with a drill bit, which is too big. I use a smaller one and tap out the blank. Use your tail stock as much as you can, especially when roughing.

While you're at it, you can get some stoppers too. I like their stoppers.

[Lyle W. Kerr]

Thanks Kyle.:D

I Google d bottle stopper mandrel and came up with the PSI one and some other ideas. I saw one where they just use a Jacobs chuck and put a mandrel in it like the one they sell at Wood Craft. Another one was the same but with a regular lathe chuck.

Ideas, ideas. . . . . never even crossed my mind on these.

I'll take a look at the PSI stoppers, the ones I saw look like the same ones at WC, they are local right in my town.

[Skip Spaulding]

Lyle, I cut a short piece of 3/8 threaded rod the same length as the screw stem on the stopper plus length enough to chuck in my drill chuck with #2 morse taper, I drill the piece I'm turning and thread it on my home made chuck, place it in my head stock, bring up my tail stock and turn. When done a little glue and screw on your stopper.

[Lyle W. Kerr]

I was thinking of trying that from what I found when I searched "Bottle Stopper Mandrel" in Google.

I know at the hardware store near my work I can get hanger bolts and machine threaded studs, actually I think I have a bag of hanger bolts, 1/4".

Why 3/8? The Stoppers I get from WC have 1/4-20 thread in them. All of the other stoppers I have made I put two nuts on the stud for the topper and forced it into the hole of the finished wood piece. No glue, removed the nuts and threaded on the metal piece. None of the ones I have, have loosened up.

I'll post some pictures. As you see the ones I make are more decorative than functional, but seriously who doesn't finish a bottle of wine?

[Kyle Iwamoto]

I put my first stopper in a 1/2 gallon vodka bottle. Use it a lot... Can't finish THAT in 1 night..... :eek:

Nice work! They do look more decorative than heavy duty use. Don't see a problem. Unless they're cork, they pull out easy enough. What finish do you use?

[Don Orr]

While you're there at WoodCraft in Manchester, inquire about turning classes at the Connecticut Valley School of Woodworking in the same building. Maybe a class with a good instructor could solve a lot of your troubles.

[Lyle W. Kerr]

Kyle. . it's only a half gallon, just kidding. Thank you, except for the spalted maple one my pieces don't have a finish on them, they are just highly polished.

I looked at the classes at WC, 245.00-295.00 yikes, the lathe was bad enough. I will talk to some people at the next CCW meeting to see if I can get any hands on help.

[Skip Spaulding]

Lyle, I use stopper from PSI, threaded stud is almost 3/8. You could probably use 1/4" threaded rod the same way. Good looking lathe!

[Jeff Farris]

Lyle,

A few follow-up questions.

Did you have the tailstock in place? If not, why not? Turning the piece I see in your photo, I would have had the piece in a chuck or between centers, but not likely on a screw center. I would use a normal drive center and tailstock, unless I had a very exotic stock where I did not want to give up any to waste blocks at the ends.

If the trunk of the tree runs parallel with the bed of the lathe, scraping is going to be a less desirable technique than cutting with the bevel of a gouge.

[Lyle W. Kerr]

The units in the picture were made on my old mini lathe. No tail-stock used except for the taller one on the right. Tail-stock was only used till in the very beginning. Normally I use the screw center because the piece will be ready after for the stopper itself. It was much easier to drill out square then round.

On the shorter pieces it was a lot easier to make them with out the tail-stock, thus the screw center, and I was able to do a lot more detail on the top, dished out etc.

Well I picked up some 1/4-20 threaded rod today to try in my Jacob's chuck. Sounds like I really need to work with the tail stock to start pieces off on the larger lathe. I may be able to try it tonight, may stop in at WC to get a spindle gouge as well.

Curious, what speeds are normally run making something like this? I have seen video online and they are going way higher then the indicated 1200RPM on my machine I am running.

[Wally Dickerman]

The units in the picture were made on my old mini lathe. No tail-stock used except for the taller one on the right. Tail-stock was only used till in the very beginning. Normally I use the screw center because the piece will be ready after for the stopper itself. It was much easier to drill out square then round.

On the shorter pieces it was a lot easier to make them with out the tail-stock, thus the screw center, and I was able to do a lot more detail on the top, dished out etc.

Well I picked up some 1/4-20 threaded rod today to try in my Jacob's chuck. Sounds like I really need to work with the tail stock to start pieces off on the larger lathe. I may be able to try it tonight, may stop in at WC to get a spindle gouge as well.

Curious, what speeds are normally run making something like this? I have seen video online and they are going way higher then the indicated 1200RPM on my machine I am running.

There lots of opinions on turning speeds. I suggest 1200 as a good speed to turn a 7 inch bowl. For small spindles, at least 2000. Surface speed of the wood is what you are dealing with, not RPM's.

In my own turning, I would turn the 7 inch bowl at 1600 and the small spindles at 2500 or more.

Wally

[Lyle W. Kerr]

Well the Jacob's chuck and threaded rod worked great with the tail stock in use!! Here is a picture of my first one off of the "New" lathe!

Thanks to all for all of the great help and advice!