hollowing tool?

[Jack Wood]

I am going to buy a tool to hollow out my bowls and the like but I'm confused by the different shapes of them. Some have straight shafts and others are curved, I know that there is a use for both but for someone just starting out what would be a good one to start with? In addition what about the "Termite" by Talon? Instead of a scrapper it has a end bit that is shaped like a ring, is this better than a blade/scraper tool? Thanks for your help!:)

[Hans Scholte]

Hi,

when I chose my first hollowing tool I thought Lyn Mangiameli's Survey of hollowing tools most helpful.
The first part is located at:
http://www.fholder.com/Woodturning/hollow-1.pdf

Apart from bowl gouges I often use the Woodcut Proforme for hollowing side grain and the Oneway termite for endgrain.

Success,

Hans

[Anthony Yakonick]

For "bowls" use a bowl gouge, for vessels and closed forms there is a multitude of tools ranging from $20 to $200+. A little more info could help narrow it down.

[Pat Salter]

I thought I heard the ring type was for cutting end grain. can it be used for cross grain?

[sascha gast]

if you want, google up the exocet tool. it's great. i used it at a show and was so impressed that i bought one. since then it is my favorite tool, and not just for hollowing. it's a bit expensive, but now that i had it for a while, i definetely would buy another one. it's such a safe way of hollowing, no catches what so ever. yo can adjust the cutter to your liking, it cuts the grain in every direction and leaves a great finish. right now i am making translucent bowls fron norfolk pine and this is my goto tool for the interior. just amazing.

sascha

[John Hart]

Jack,

Yesterday, I tried my first semi hollowed form....sort of a vase kinda thing. I punched myself in the face about 20 times before I finally decided, "John, you don't have the right tools for this!!" (I learn slowly:rolleyes: )

Anyway, I decided through my pain that what I really needed is a good gooseneck tool rest and longer handles. I think it would have better that way. After I heal, I'll give it another try.

[Carole Valentine]

John, you really need at least two for HFs, IMHO. A straight boring bar to open up the vessel after you have drilled the initial hole and an angled bar to work on the sides. Depending on the size of the opening, you may need a swan neck as well. I use the Scorpion/Stinger sets and a Sorby Hollowmaster. There are still times that I cannot reach certain areas of some forms. For that reason I need to learn to do collars so I can hollow thru a larger opening!

[Raymond Overman]

John,

The different hollowing tools are used to reach different areas of hollow forms. Around the shoulders of a hollow form you may need a curved boring bar to get the cutter to the wood. The straight boring bars offer stability to get to the bottom of the turning and give you a mechanical advantage when it's hanging off of the tool rest further than you normally work.

I like the straight and curved style of boring bars with 1/4" cutters in the middle of the bar. I made my own straight boring bar with a piece of 5/8 cold roll steel, a cutter, and a homade handle. It works very well for having less than $10 in materials. My post last week with the vase shows what the tool can do when hollowing end grain. John Jordan sells a set of 2 small tools or 3 large tools with these characteristics that are reasonably priced. They come unhandled. (not affiliated)

I've also used a ring tool and don't like it. I had a couple of issues with it. The cutting edge has to be at a specific orientation to work correctly and if not, it can create a fairly violent catch. There's a fine line with riding the bevel on this and the catch and the learning curve isn't worth it to me since I had a boring bar that was working. Also, when it did cut correctly, it seemed that the tool became clogged quickly. Other people may like the tool and your mileage may vary.

[John Hart]

I don't want to hijack Jack's thread but hopefully through my ignorance, Jack you can get answers to your questions! (makes me sort of an expendable laboratory animal) :)

Carole and Ray...you seem to agree to the same end..but through different means...that's a good sign to me.

I really want to make my own tools so I'm very interested in aquiring the right kind of steel and doing it correctly. This the main reason I'm so interested in how folks create lathe tools from old files. My BIL is an accomplished welder so I'm asking him for some custom tool rests....when he finds his round tuit.:rolleyes:

I'm a steel moron. My ability of identifying the difference between Cold Rolled and 302 stainless is limited to using magnets and looking for rust.:rolleyes: I have some steel bars but I don't know what it is or whether it'll hold an edge or anything.

I'm going to keep listening to ya'll for tidbits so I can get to this correctly.

[Raymond Overman]

John,

Maybe we're not getting too far away from the original thread. Let me preface by saying I'm a young guy. I'm safety conscious but I try to do things cheaply. Most of my knowledge I've gotten from reading and talking to other turners and there are a lot of opinions out there.

You can purchase a 1/4" steel cutting bit for $5-$15 depending on source. (Packard is where mine came from) I used a 5/8 round cold roll steel bar from the big orange box for $4. I cut it in half and put it on my lathe into the morse taper through my talon chuck and tightened down on it. I used a metal cutting drill bit in my jacobs chuck to drill a hole in the end of the rod. I put a small flat on the side and drilled another hole in the side of the rod. I use thick CA glue to hold the bit in the tool. you could tap the hole in the side and use a set screw. I turned a tool handle out of some scrap pecan and used a 1" piece of copper tubing for the ferrule.

I've also had friends that made their boring bars out of 3/4" drill rod. They're nice looking tools. Make sure to slow the speed of the lathe down when working with metal and use some kind of lubricant. I used a silicon spray.

The important part is the strength of the cutting tip. I have read that it is not a good idea to use old files as cutting tips or scrapers since the ridges represent weaker spots in the steel and catastrophic failure could occur leaving little pieces of metal projectiles flying around in your shop. Some people may argue this point and say they've been using them for years. It only takes once.

Feel free to ask questions. I'll try to take and post pictures of my homemade tools this evening.

[Carole Valentine]

I am also a "steel moron" as John so aptly puts it. What is "cold rolled" and opposed to what else? Can it be drilled on a lathe that has a slowest speed of 500 rpms?

[Raymond Overman]

Carole,

I knew that by posting I would seem to know more than I do. I'm really only smart enough to get the job done. Cold roll steel is fairly soft, common steel. Drill rod is comparitively soft as well. It's not hardened like tool steel or M2/M4 etc steel that tools are made of. It makes good holders for the cutting tips because it's inexspensive but it won't hold a sharpened edge and therefore doesn't make good cutting bits.

As long as you are careful, you should be able to drill the rod with your lathe. Just make sure to use lot's of slick em' (silicon, wd-40, pam, etc.)

[Cecil Arnold]

Carole, while not a steel wizzard, I'll share what little I know about this stuff. You can purchase good tool steel from a number of suppliers, or find a knife supply store. Two places come to mind, first, here in Houston we have a place called Rex Supply, who can give you anything from 1X1/8" flat stock increasing by 32nd and 1/4" increments to about anything you want--they also have round stock. This is available by the foot and the price varies depending on the steel you want. The common grades, used in knifemaking, are A-0, O-1, and D-2, plus any number of "stainless" steels. A- steel is air hardened, O- is oil hardened, and I really don't know why D-2 is what it is. When you buy this stuff it is not hardened, otherwise you could not work it. After shaping the steel it is time to temper it, which means hardening it. To temper you heat it up to a set temp. (anywhere from 1200 to 1900 degrees) which vaires by the type of steel you are using, then quench in the appropriate media--air, oil, or ?? Once tempered the steel may be too hard to use. This is often the case. Tempered steel may have a hardness (measured by the Rockwell C scale) in excess of 62, which is way too hard for most applications, is brittel, and will chip and shatter. In order to "draw" the temper, lowering the hardness to something on the order of 58-59, it is necessary to heat the steel up again, to a lower temp. (something on the order of 450-500 degrees, for a half hour or so) and you are finished except for putting a handel on and sharpening. This would be the route to go to make some really nice custom scrapers as you can get 1"X1/2" stock for example, that should not tend to chatter when you have to reach the bottom of something deep. Most people work steel using belt sanders so you can change the belts when the abraisive is gone and to be able to change abraisives as necessary. You usually start with about 220 and work to 400 grit. I know that's more than you wnated to know, and am sorry if I hijacked the thread.

[Bill Stevener]

Hello Jack,

This may help some. I maid my own hollowing tools and they work just fine for me. You may wish to try the same. The stock is key stock that you can buy at ACE. 5/8" & 3/8" x12" for about $3.00 each, two grub screws $0.25 each. The drill end of a drill. I used o.225" only because I had a case of 25. use what you have. For the ferrule copper, brass, or s/s tube. I used s/s again because I had some 1". Your wood for the handle -- 14" ?? The stright bar has two holes, one at an angle and one stright.

Total cost for 3 tools, no more then $9-10.00 cheep enough, and tough.

Photos attached.

Bill.>>>>>>>>>:)

[Carole Valentine]

Quenching red hot (white?) steel in oil???? Wouldn't the oil catch fire?

[John Hart]

Geez Bill....Those are great!!! Is there anything you DON'T do??? ;)

Once again...Inspiring!

[Bill Stevener]

Hi John,

Really very simple, give them a try. Work just great. Back to building Gerri's sun-room, I don't paint!!!:eek:

Bill.>>>>>>>>:)

[Cecil Arnold]

Yes, it flashes. There is a chart available, I saw one at a welding school, that you can use as an indicator for temp. Nothing goes to white hot, usually it is some shade of red. The oil goes out as soon as the steel cools. The flash fire comes from the hot steel and it never gets the oil to the temp needed to support continued combustion. This assumes that you have an adiquite amount of oil--say a gallon.

[Earl Eyre]

This is another answer that really agrees with much of what is being said, but for "morons" that don't want to get into making tools, etc. Making your own is certainly cheaper. Many of the tools like the Termite certainly do a great job. But if you want to start hollowing and want a set of hefty tools that will reach in a long ways and have been doing the job for years, you can't go wrong with the Robert Sorby, or similar, systems. Get the the armbrace, the hooker tool and something like the Omni Tool from the Stewart system and you can hollow just about anything. All told, you will be out a few dollars, but it's a system that can reach about anywhere and with the shear scraper blade you can leave a surface very smooth.

There are alot of specialty tools that work great but you will end of needing a lot of different ones. Something like the Sorby system (there are other similar--pick any of them) there is very little you can't do.

I know this is an old fashioned answer and these tools aren't on the cutting edge of new toys but you will end up using them for all sorts of things and you can always add to them when you get more specific about the types of turning you do.

Earl

[Earl Eyre]

Maybe I better add a P.S. to my above comments. I should have said "steel morons" not "morons". LOL I wasn't trying to imply any of us are morons, in general. It's just that I know I'm a steel moron and I've tried making my own tools and they never work very well!

In fact I made a set of hollowing tools. One bent the first time I got a catch (wrong kind of steel!) and the other one, I couldn't keep the tip sharp for six passes in the wood (wrong kind of steel for the tip!). I gave up and bought the Sorby set and have never turned back.

Earl

[Dennis Peacock]

Jack,

You've for sure gotten many answers here.

For the sake of simplicity, all you really need for hollowing out a bowl is a fingernail grind 1/2" bowl gouge. A properly ground and sharpened bowl gouge with an "Elsworth" grind on it and you can present that tools to the wood in at least 12 different ways for making various cuts to get at the results you are looking for. You do not need a hollowing set for making bowls. For vessels and vases and stuff like that.....THEN you need a hollowing set of tools.

Get yourself a good bowl gouge of 1/2" or 5/8" M2 of PM steel and you'll never look back.

[Andy Hoyt]

Bill Stevener - Thanks for the tip to this link.

Bumping it to the top since its quite topical.

[Ernie Nyvall]

Lots of good info in this thread. Thanks for the question Jack.

Ernie

[Stu Ablett in Tokyo Japan]

Bill, those are really nice looking tools!

Cheers!