Busted My Tool Rest ;-(

[William Young]

Yep, ... I got a catch. 😱 Not a very big one at that and I was surprised how easy that cast iron snapped. I was working out toward the end of it so I guess leverage played its part. So I guess it's off to Lee Valley (via online order) for one of their pricey newfangled ones like this .
http://www.leevalley.com/wood/page.aspx?c=1&p=46452&cat=1,330,49238&ap=1
unless someone can tell me where there is one just as good for less money.
I'm not beat though. I still have a 7" one because only 5" broke off. 😉

Any suggestions besides the LV ones for an alternative replacement?
W.Y.

 

[Norm Smith]

Hi William, I went to a machine shop and had them cut the proper size bar for the post and rest ant get them to weld them together. $10.00 is what it cost me.
Norm

 

[C Edward Moore]

Why?

Hi William,

I like Norm's suggestion. Best Wood Tools has good modular tool rests.

Most important, have you analyzed WHY the catch occurred? Some of your posts suggest that you haven't made lots of bowls yet. So, I'll take the approach here that I do with folks just starting out. If they get a catch I make them turn the lathe off and figure out why that happened -- because if I don't, they will keep getting that same catch. There seem to be two main problems that occur.

1. They push too hard as the tool reaches the bottom of the bowl, the tool crosses the center and is picked up by the wood on the other side, carried up and slammed back down on the tool rest on the near side.

2. While working on deepening the bowl halfway between the rim and the center a groove is created. On successive cuts, the tool goes into the groove near the end of the intended cut and both sides of the tool are engaged -- which cause the tool to grab since it can't cut all that wood at one time.

We all get catches, but we rarely need them. 😀 😀

It's always interesting to watch what happens to a newbie who has just had a catch and analyzed it. I've had some repeat the problem right away, meaning that their determination exceeds analytical skills. 😀

 

[William Young]

Ed.
It was one of those rare catches that caught me off guard. Probably by carelessness and being in too much of a hurry. I used to get all kinds of catches but I seldom do anymore since getting Bill Grumbines 2 hour DVD. That DVD was excellent. Almost like having someone right here teaching the technique of using the bowl gouge..

Norm;
Thanks for the welding idea for a new one. Wife and I head to town almost every morning . It's a habit to go to A&W and socialize with the 10.00AM coffee crowd. I'm retired you know.. 😀 🙂 Gotta do stuff like that.
I'll take the pieces in to the machine shop there and see if he can make me up a new tool rest to the right dimensions of shaft etc..
I have heard lots of reports of those cast iron tool rests snapping like that. Now I know why.
W.Y.

 

[Fred in NC]

I have had catches too!

But never broke a tool rest or banjo.

My question is, say we get a totally unbreakable tool rest. We have the same catch that broke the cast iron rest. Now, the tool rest does not break.

What happens then? What gives?

 

[William Young]

Hi Guys;
I took it to town this morning to see if I could get a round one made up at a welding shop . It wouldn't be chrome steel like LV's but also would only cost a fraction of the price. But I ran into a little hitch with the size. The shaft is just under an inch so I called LV to see if their 25mm one would fit and they couldn't answer me. I dont want to pay shipping both ways if it didn't fit right .

So I went to plan B and called BusyBee where I got the lathe and they have a new one in the mail under warranty.
Eventually I would like to get the modular set but finances dont allow that at this time.
I have always had great service when dealing with BB and this is just another example of that.
W.Y.

 

[dkulze]

Hey, Bill.

I'm going to be looking for a metal shop soon as I'm tired of paying for rests and not fully liking what I get. I've done just enought metalwork to know that getting someone to make me one out of round steel stock would be pretty easy, and that I could get custom curves made for only a bit more.

Run your micrometer into that banjo mount and tell me how big the post is. It's actually OK for the post to be a bit less than snug, as long as it's not floating around in there. It would probably be cheaper to order a bit of custom round stock for the local welder to work with than to order the rests, too.

Dietrich.

 

[Bowen Turner]

I had a welding lesson this weekend that had been postponed. Prior to going I went to the local Metal & steel store and spent $13 USD on pipe. A length about 3ft of 1" round, same at 5/8th round and two flat bar, one about 1 1/2" by 3ft and the other 1" by 18".

I was going to use the 5/8th & two flat bars as cross bars on the 1" post.

Anyway, At the end of my lesson I had welded the two modular posts to the larrge and small bowl rest as they always seemed to unscrew during turning, added a length to the post of a Delta tool rest extension so it was long enough for my lathe, made two brand new tool rests, one 1" x 14" and the other 1" x 3.

They all appear to be straight and all told I think I have saved about $150.
I had a great time and still have lots of metal left.

Now, if I can do it, William, I sure know you can!

 

[William Young]

Yes I did get a quote in town and he said $10.00 labour and $12.00 material and he could make me any one I wanted including the bent ones for bowls. He said he has made some for his dad and he knew exactly what I was talking about. So I will get my new one under warranty and then probably get him to make some custom ones for me one at a time over a period of months.
I did some welding in another life but I dont have a welder now.
W.Y.

 

[-e-]

check out =/bestwoodtools/

i've been using their interchangeable ttoolsrests for years ... love em

and they will make up special sizes for you..

http://store.yahoo.com/bestwoodtools/

 

[uniquewoodworld.com]

But never broke a tool rest or banjo.

My question is, say we get a totally unbreakable tool rest. We have the same catch that broke the cast iron rest. Now, the tool rest does not break.

What happens then? What gives?

Fred makes a good point. Im surprised nobody's chimed in?

Ive broken a couple jet extension arms turning nasty coarse grained woods like Ash--trying to do a nut dish--the point where the outside edge of the inside bowl meets the inside/bottom of the outside bowl can be a bear... I feel your pain...

My father in law is a machinist. Told me that my jet extension arm was actually cast steel, not cast iron. He actually heated both sides of the broken arm til white hot and joined them back together. Then, he welded a 3/8" solid steel plate along the top of the arm. Now that I have this bionic, indestructable extension arm, Im wondering the same thing as Fred. What happens now that it doesnt break lol. Does the tool break? Wood shatter? Which is the lesser of the two evils.

My lathe is in the garage, and its about 20 degrees out there today. I wont be finding out anytime soon lol.

 

[TEK]

Fred makes a good point. Im surprised nobody's chimed in?

Ive broken a couple jet extension arms turning nasty coarse grained woods like Ash--trying to do a nut dish--the point where the outside edge of the inside bowl meets the inside/bottom of the outside bowl can be a bear... I feel your pain...

My father in law is a machinist. Told me that my jet extension arm was actually cast steel, not cast iron. He actually heated both sides of the broken arm til white hot and joined them back together. Then, he welded a 3/8" solid steel plate along the top of the arm. Now that I have this bionic, indestructable extension arm, Im wondering the same thing as Fred. What happens now that it doesnt break lol. Does the tool break? Wood shatter? Which is the lesser of the two evils.
My lathe is in the garage, and its about 20 degrees out there today. I wont be finding out anytime soon lol.

It's down too this. With that much force something has to give! Either the tool rest breaks or bends, the tool breaks or bends, the wood breaks or flies off of the lathe, the motor stalls, the drive belt slips, or the work slips in its drive center or chuck. Hmmm! Maybe it's possible to break a chuck also. The point is the weakest point or points are going to give. Mostly I've had to chase my pieces across the floor and some weren't too pretty after I picked them up. I'm still working toward perfect technique. Another 20 years of turning and I’ll almost have it.

 

[Fred in NC]

The weakest link

I brought up the question, but I don't have the answer. What gives?

Would the catch force the tool's handle up, carriying the hand you have on top of the tool with it, between the wood and the tool rest? (Which is a case for my underhand turning !!!) What part of your body will the tool handle encounter on the way up? (I am not trying to be NOSEy)

Would a cast iron or steel tool rest break if you happen to have the tool right on top of the shaft, like in the middle of the tool rest in most cases?

Will the faceplate give? Will the glue line in a glue block give?

Something like the Sorby Stebcenter gives .... but of course there is cousin INERTIA who thinks otherwise.

I have worked with machinery where one of the gears, called a sacrificial gear, is made of phenolic. It can take everyday forces, but will break if they are exceeded.

WHERE DO WE WANT THE WEAK LINK IN A LATHE?

 

[William Young]

Fred;
You have brought up some very legitamant questions.
However, there are many variables . Perhaps you havn't got the responses you have been looking for because it is a subject that cant be answerd in a few words . Thus my lengthy reply here.
In my particular case it happened so suddenly that I didn't have time to think about how it happened. After analysing it I came to the conclusion that I was working on an unfamiliar cut on the back side of a project which made it necessary to work at the extreme end of a 12" tool rest. If I had a 6" or less tool rest I would have used that in that awkward spot and it would have been much safer. In time I will aquire a variety of different lengths and specialty shapes of tool rests.
But when the catch happens it is a split second thing and it's over before you know it. Apparently my motor and my Oneway Talon chuck were stronger areas than the cast iron tool rest so the leverage when working on the far tip of the rest is what snapped it and what surprised me most was that it really wasn't a very big catch. I was able to easilly turn out the damage in the area of the catch without loosing any of the profile I was trying to acheive.
You ask if a cast iron or steel rest would break if the tool was in the centre on top of the post. I doubt very much if either one would break in that case and certainly not a steel one. But then the piece that holds the tool rest (banjo ?) could break with a big enough catch if it was cast iron.

Will the faceplate give?... very unlikely if it has long enough and strong enough screws properly securing it on. .

Would the glue line in a glue block give ? .. I could certainly imagine that happening but it never did on any that I glued up before I got my Oneway chuck. But that was on my mini lathe. I personally would not trust a glued on block with the power that I now have and swinging bigger and heavier pieces with my full size lathe .

One of my first cheap tools I had before upgrading to high quality ones was a little 1/4" bowl gouge and before I learned more about using a gouge I actually bent the shaft of that gouge in a catch and the steel was soft enough to hammer it back to straight on an anvil. And that was when I had my little mini lathe with just a 1/2 HP motor.

I seldom get catches with doing standard bowls anymore and if I f do they are generally quite minor because of Bill Grumbines excellent DVD but there all kinds of other turning tools and techniques that I am going to have to master (or at least practice) in the next 6 months or so and I feel certain that more catches are in my future until I get more experienced in some other areas of turning.
But that is a challenge I am looking forward to.

I hope I have answered some of your questions to your sataifaction and because I am relatively new to turning I am only relaying my own experinces as well as some of what I have read in several other turning forums.
I hope some of the more advanced turners will follow up and give both you and I some expert advice on the subject.
W.Y.

 

[William M. Zerby]

William,
There are a couple of options. I have a welder-friend who says there is a rod that is designed to weld cast iron. Also Woodcraft makes a set of tool rests that have interchangable posts (diameter). They are topped with a 5/16" hardened drill rod to make them less prone to dinging. I have silver-soldered 1/4" hardened drill rod to cast iron tool rests for 18 years with great success.

Kindest regards,
William M. Zerby

Yep, ... I got a catch. 😱 Not a very big one at that and I was surprised how easy that cast iron snapped. I was working out toward the end of it so I guess leverage played its part. So I guess it's off to Lee Valley (via online order) for one of their pricey newfangled ones like this .
http://www.leevalley.com/wood/page.aspx?c=1&p=46452&cat=1,330,49238&ap=1
unless someone can tell me where there is one just as good for less money.
I'm not beat though. I still have a 7" one because only 5" broke off. 😉

Any suggestions besides the LV ones for an alternative replacement?
W.Y.

 

[dkulze]

I think the single most important thing I've seen written at this point was the question "where do we want the weak link in the lathe?" It seems that we, to some degree, want to plan for the weakest part to be the least expensive weighed off against the least dangerous.

Glue joint: really cheap if it breaks but ya got a chunk of wood flying across the shop.

Faceplate: same thing.

Chuck: never heard of this actually happening so is probably moot.

Tool: can be pretty expensive and you have a chunk of very sharp metal flying around.

Toolrest: Medium expensive but, once again, can have a chunk of metal flying around at a pretty good clip under the right circumstances.

Lathe: If it's a belt, you might just burn out the belt, If motor, do stalls damage the motor? On mechanical drive, will you strip out the gearing? That would be pretty pricey.

You: Well, I'd rather not go there with this one.

the piece: Wood shrapnel and loss of effort. The loss of effort is really no biggie but the wood shrapnel can be extremely dangerous. A 20lb chunk of wood puts a flying piece of metal to shame.

So, conclusion: We're best off taking out time, working on good technique, keeping out tools sharp, and wearing good protection.

Past that, I'd vote for glue seam or faceplate screws. Wonder if using drywall screws would allow breakoff?

Dietrich

 

[William Young]

Dietrich;
I have heard many times to never use drywall screws for attaching the chuck to the wood and Bill Grumbine even goes into that in detail on his DVD. They are brittle and can snap easilly.
W.Y.

 

[dkulze]

That was actually kinda the point. If they snap off, they can be the weakest link to prevent blowup or tool breaking. I think they probably snap off too easily, though.
Dietrich

 

[Fred in NC]

Some kind of sensor.

A sensor to detect the overload and disconnect the power. Of course, there is still the inertia of a large and heavy block of wood.

A shaft coupling that will disconnect on overload.

A turner who never has catches !