Page 1 of 2

How many times has this happened to you?

Posted: Fri Oct 21, 2011 11:08 pm
by frazeeg
So today I finally got to work on another pipe. I had broken the tool rest on my lathe earlier this week and had it welded back together, hence the hiatus. This pipe was being made of the coffee burl I acquired a month or two ago, and I was looking forward to shaping it.

I drilled the draft hole and mortise, and then shaped the shank as far as I could. No problems. Drilled the chamber, then widened it with the spade bit I ground down for that purpose. Even got it PERFECTLY aligned with the draft hole. I was amazed it was so spot on, especially considering I couldn't square up the block (part of it was still burl-edged) and had to eyeball it. Started shaping the bowl, and was almost finished when the following sequence of events happened, all within 1 second of time:

1.) My gouge caught on the bowl, which:
2.) Jammed into the repaired tool rest, snapping it clean at the weld, which then:
3.) Sent the gouge into the rapidly spinning shank, which popped right off the bowl.

I have no idea where the broken-off shank flew. My tool rest is busted now and hell if I'm gonna try repairing it again. Bought a new one online but now I gotta wait for it to come in the mail.

So, yeah, just when I thought I was doing great, I broke the pipe I was making and put my lathe out of commission for a week, all within a split second. Welcome to the world of pipemaking, it seems. :banghead: :filth-n-foul:

Re: How many times has this happened to you?

Posted: Fri Oct 21, 2011 11:33 pm
by TRS
frazeeg wrote:Welcome to the world of pipemaking, it seems.
Yup! :D I think I've spent more time repairing my lathe than I have making pipes; but it's character-building!

Re: How many times has this happened to you?

Posted: Fri Oct 21, 2011 11:49 pm
by Sasquatch
How in the holy flying pancake did you break the tool rest the first time? Or the second? I mean.... that just.... shouldn't happen. I've screwed things up on the lathe a few times, but what you're talking about sounds outright freaky, like you are doing something wrong. :?:

Re: How many times has this happened to you?

Posted: Sat Oct 22, 2011 12:01 am
by frazeeg
Sasquatch wrote:How in the holy flying pancake did you break the tool rest the first time? Or the second? I mean.... that just.... shouldn't happen. I've screwed things up on the lathe a few times, but what you're talking about sounds outright freaky, like you are doing something wrong. :?:
I was green-turning a bowl the first time. I had chainsawed a log into six hunks about 9" octagonal and was turning the first one down so I could set it aside to dry for a year. My roughing gouge caught in the wood and snapped the tool rest clean off the shaft. I wasn't happy.

The second time it broke doing the same thing, after I had paid to get it welded. Again not happy. So I decided to JB Weld it. It worked for a while, until, well, you read that already. Guess that's what happens when your tool rest is cast iron instead of steel. Cast is more brittle if my engineering education serves me correctly, hence it snapping instead of bending.
BeatusLiebowitz wrote:
frazeeg wrote:Welcome to the world of pipemaking, it seems.
Yup! :D I think I've spent more time repairing my lathe than I have making pipes; but it's character-building!
I just hope it doesn't turn into a common occurrence. My dad and I have had the lathe for about a decade now and this is the first problem we've had with it. It's a Jet midi lathe.

Re: How many times has this happened to you?

Posted: Sat Oct 22, 2011 6:25 am
by taharris
I guess I see two issues that you need to address.

The first one is that you need a new tool rest and you have indicated that you have already ordered one.

The second is that you need to try to remember exactly what you were doing when the catch happened and try to understand what you were doing wrong. It sounds like you are getting a lot of catches and you should solve this problem or you will continue to risk damaging your equipment or yourself.

For example, I like to use a bowl gouge when turning pipes. And it works great, except if I'm not careful when I'm shaping near the bowl/shank intersection the wing of the bowl gouge can catch on the wood 90 degrees from the cut and cause a spectacular catch. Now that I know this I can adjust my approach angle accordingly and avoid catches.

Todd

Re: How many times has this happened to you?

Posted: Sat Oct 22, 2011 12:53 pm
by frazeeg
taharris wrote:For example, I like to use a bowl gouge when turning pipes. And it works great, except if I'm not careful when I'm shaping near the bowl/shank intersection the wing of the bowl gouge can catch on the wood 90 degrees from the cut and cause a spectacular catch. Now that I know this I can adjust my approach angle accordingly and avoid catches.
That's almost exactly what happened. I think I adjusted the attack angle of the gouge and instead of cutting, it just dug into the wood, hence the catch. That and I had to have the tool rest spaced about 2" from the bowl to keep it from hitting the shank as it spun.

I think the next purchase will be a set of #2 Tower Jaws for my Talon Chuck. I've been getting by on just the standard #2 jaws which only have 1/2" or so of grip. I don't feel comfortable with their gripping power while turning so I've been using a tapered live center in the mortise and chamber to turn the shank and the bowl down. My tool rest is too wide to fit in the small gap created by this situation, which is why it was 2" from the workpiece.

Re: How many times has this happened to you?

Posted: Sat Oct 22, 2011 4:00 pm
by KurtHuhn
frazeeg wrote:That and I had to have the tool rest spaced about 2" from the bowl to keep it from hitting the shank as it spun.
Well hell, that ain't safe! :twak:

Re: How many times has this happened to you?

Posted: Sat Oct 22, 2011 4:51 pm
by Sasquatch
Sounds like you need to be carving your pipe along the spinning axis, rather than perpendicular to it. A LOT of pipe making requires what amounts to steep bowl carving techniques, working from "on top" of the pipe, rather than working at the side.

Re: How many times has this happened to you?

Posted: Sun Oct 23, 2011 12:09 am
by frazeeg
KurtHuhn wrote:
frazeeg wrote:That and I had to have the tool rest spaced about 2" from the bowl to keep it from hitting the shank as it spun.
Well hell, that ain't safe! :twak:
Yeah, I know. But like I said, since I was just using the short #2 jaws, I used a live center to keep the pipe in the jaws. With that there, here wasn't enough room to move the tool rest to the side. Once I get the tower jaws, this will hopefully not be an issue.
Sasquatch wrote:Sounds like you need to be carving your pipe along the spinning axis, rather than perpendicular to it. A LOT of pipe making requires what amounts to steep bowl carving techniques, working from "on top" of the pipe, rather than working at the side.
You mean carving with the tool rest parallel with the top of the chamber and working my way down the bowl? That doesn't sound much safer than what I was doing, though you undoubtedly know more about this than I do. I more or less followed Kurt's video from this thread.

BTW thanks for that video Kurt - it helped a lot.

Re: How many times has this happened to you?

Posted: Sun Oct 23, 2011 10:02 am
by KurtHuhn
frazeeg wrote: Yeah, I know. But like I said, since I was just using the short #2 jaws, I used a live center to keep the pipe in the jaws. With that there, here wasn't enough room to move the tool rest to the side. Once I get the tower jaws, this will hopefully not be an issue.
The tower jaws are immensely helpful for bowl turning. You can secure a block of wood with the regular #2 jaws, and it should be fine, but you're mostly restricted to straight pipes and slightly bent pipes at that point. I used the regular #2s for a few years before I found the Towers, and the difference is amazing.

I haven't found a need to use a live center at all these days. Just crank those jaws down and start turning.
frazeeg wrote:BTW thanks for that video Kurt - it helped a lot.
You're welcome! I intended to get a couple different angles on that, but was on a time crunch. Now that things have calmed down, and 30 identical pipes are packed up and waiting to go to the post office, I might find time to get a more "professional" looking video created.

Re: How many times has this happened to you?

Posted: Sun Oct 23, 2011 10:29 am
by TRS
KurtHuhn wrote:30 identical pipes are packed up and waiting to go to the post office
:?:

Re: How many times has this happened to you?

Posted: Sun Oct 23, 2011 11:45 am
by Sasquatch
frazeeg wrote:You mean carving with the tool rest parallel with the top of the chamber and working my way down the bowl? That doesn't sound much safer than what I was doing...

Well, what you are doing is wrecking pipes, but more notably actually wrecking equipment. Ergo, what you are doing is somewhere between "subideal" and "outright dangerous".

Check out this video on Blakemars - the first minute is all face-on bowl carving. He's using what amounts to a bullnosed scraper, as far as I can tell. I use a combination of a large scraper for roughing and a 3/8" gouge. Using the gouge, you rotate the tool almost 90 degrees in your hand so that the bottom of the tool is rubbing on the wood as it spins down and past. Then you change the approach angle, swing the tool handle out toward you, and engage the cutting edge. You can peel of real thin ribbons this way. I will go get a picture of this.

Re: How many times has this happened to you?

Posted: Sun Oct 23, 2011 11:59 am
by Sasquatch
Viewed from above, here is the setup. Notice how close the rest is to the workpiece. Your cutting edge on the gouge is almost vertical and this results in a shearing cut that leaves the surface very smooth.

Image



And you won't break anything.

Re: How many times has this happened to you?

Posted: Sun Oct 23, 2011 12:00 pm
by Sasquatch
Image

Re: How many times has this happened to you?

Posted: Sun Oct 23, 2011 4:40 pm
by frazeeg
Ok, that makes more sense. I'll give that a try out...once the new tool rests come in the mail.
Sasquatch wrote:Check out this video on Blakemars - the first minute is all face-on bowl carving. He's using what amounts to a bullnosed scraper, as far as I can tell. I use a combination of a large scraper for roughing and a 3/8" gouge. Using the gouge, you rotate the tool almost 90 degrees in your hand so that the bottom of the tool is rubbing on the wood as it spins down and past. Then you change the approach angle, swing the tool handle out toward you, and engage the cutting edge. You can peel of real thin ribbons this way. I will go get a picture of this.
I never thought of using a scraper for roughing, though I suppose that would cut down the risk of the tool racking out of my hands since the scraper would be sitting flat on the rest, instead of a rounded gouge. Usually I try to get the tool rest as close to the workpiece as I can (plenty of bowls turned this way) but this was a special case because of the live center. Live and learn I guess. :)

I don't think the link for the video came through - could you please repost it?

Re: How many times has this happened to you?

Posted: Sun Oct 23, 2011 6:05 pm
by Sasquatch

Re: How many times has this happened to you?

Posted: Sun Oct 23, 2011 6:57 pm
by taharris
frazeeg wrote:I never thought of using a scraper for roughing, though I suppose that would cut down the risk of the tool racking out of my hands since the scraper would be sitting flat on the rest, instead of a rounded gouge.
Make sure that you use your scrapper on a downward angle between the tool rest and the work piece. If the scrapper is at a rising angle you, again, risk a spectacular catch.

Todd

Re: How many times has this happened to you?

Posted: Sun Oct 23, 2011 9:45 pm
by wdteipen
It's never happened to me. I turn probably 95% of my pipes and stems with the approach that Sas pictures.

Re: How many times has this happened to you?

Posted: Sun Oct 23, 2011 10:45 pm
by frazeeg
Why is he resting the scraper on another tool instead of the rest? I've never seen that before, and it seems more dangerous than what I was doing before...

Re: How many times has this happened to you?

Posted: Sun Oct 23, 2011 10:52 pm
by Sasquatch
I'm not sure if that's part of the rest, sort of a floating thingamabob, or what. That video is actually full of all sorts of eye-popping dangers - long floppy sleeves + rotating equipment = broken bones, for example. But he does use a "head on" approach and I thought it was worth you seeing it live.