Thread Chasing

[Grant Mack]

Hello All,
I know this may have been a thread before (no pun intended), but as a newcomer who wants to try thread cutting\chasing, can you tell me what Australian woods are suitable.
All the info I can find is for English timber such as Box or Laburnum.
I can access mainly WA timbers and some exotics (to WA) such as Olive and Queensland Box or Bush Box (Lophostemon confertus).
Regards
Grant MacKinnon

[robo hippy]

I thought about hand chasing, then took a 3 day workshop with Bonnie Klein. I bought her thread cutter, and jig. It is like cheating, but the cutter will allow you to cut threads in just about anything. Allen Batty said the only American wood that was suitable is Mountain Mahogany. Specific gravity is about 1.2, and density/hardness is almost to what Lignum is. Straight, smooth even grain. Coarser woods like locust doesn't work well, or like oak. Sugar maple is possible. You are using a scraping cut to make the threads, so tear out is highly probable. If you cut them in about half way, and use a soft wax (I use Mike Mahoney's bees wax/oil stuff that I finish off my bowls with) on a toothbrush to wax the threads, then the last bit goes more smoothly. A soft oil finish might work as well, like walnut oil, or maybe even a wiping poly oil.

robo hippy

[Grant Mack]

Thanks Robo Hippy,
I was starting to think today that I had stumped the panel in that no-one had replied.
I live in Western Australia so don't get access to things such as Bonnie Klein or other USA stuff.
Also I really only get ready access to local WA timber a lot of which is hardwood eg Jarrah (Eucalyptus marginata), but very dusty and hard if old but splinters like crazy.
I want to turn threaded boxes.
Anyway "G'Day from WA" to coin an expression.
Regards
Grant

[joe greiner]

Here's some links for thread chasing:

ATBQ - Hommage Posthume (http://www.atbq.qc.ca/introjm.htm)
Hit "next" then select "Woodturning Jigs." Scroll down to the last picture and click for more.

And another: Wood turning (http://homepage3.nifty.com/manasan/english/diy/turning/turn-1.htm)
Scroll down to Aug. 01/2004 for Threading Jig.

Similar devices can be built based on a cross-slide vise to hold the workpiece spindle.

Cheers,
Joe

[colhu]

Hi Grant

We had Ernie Newman from the Blue Mountains Woodturners demonstrating manual thread chasing at our woodturning group meeting a few years ago now. Have a look at his web site at:

e r n i e n e w m a n (http://www.ernienewman.cjb.net/)

The thread chasing page talks about good and not so good Australian timbers.

I bought a set of his thread chasing tools, made from die nuts, and tried them a couple of times with mixed success, but I didn't persist long enough to master it.

I am sure Ernie would be happy to correspond with you about it if you can find contact details for him.

cheers, Colin

[robo hippy]

If you have metal working skills, and a machinist friend or two, you could make your own. I know the cutters are standard tools ordered from some big supply place, which mount in a mandril. You mount the blanks in what machinists call an X Y jig, which means you turn two cranks, one to move the blank into the cutter front and back, and another to move it inwards towards the cutter side to side. I just cheated and got the jig. You do need dry wood, and I rough turn my blanks first, even if they are dry because the wood will 'adjust' as you remove mass.

robo hippy

[John Lucas]

Grant I'm new to this forum and just saw your question. I decided last year to learn thread chasing. It is interesting and not that hard to do. I don't have access to a lot of woods that are hard enough to successfully do thread chasing so I have been learning with PVC pipe. I suppose any plastic pipe might work. It doesn't come in sizes that let me practice actually mating the the threaded pieces but you can turn both inside and outside threads on it. Once you have a feel for how the technique works you can move onto wood.
I built my own threaders with a V file and a thread gauge to check the accuracy of the threads. So far I have had decent success with them but I'm still pretty new at chasing.
Tonight I will start trying to use epoxy in softer woods for thread chasing. Like Robo I've done most of my threading with a threader that I got from www.bestwoodtools.com Bonnie Klein's is nice and so is the one Soren Berger sells.
Anyway the woods I have access to are too soft for chasing so I am going to cut a groove in the wood and fill it with epoxy. Then I will turn away the wood and leave an epoxy lip to chase the threads into. I saw an article on the web on doing this so hopefully it should work.
What I did to learn chasing was simply to go out to the shop each night and try to chase a thread in the PVC pipe. I only did this for 30 minutes or so and then went on to the other projects I had to do. by the end of the week I was chasing a halfway decent thread. I tried a box from some dry Cocobolo I had and it came out OK. The threads were a little off. The next one came out much better. I'm still new enough that I'm nervous each time I do it and I can screw up pretty easily but I'm going to practice a lot over the next 3 or 4 weeks and should improve.
Watch one of the video's on thread chasing. I think the one I watched was Alan Batty. It helps show you a few tricks and gives you the confidence to give it a try.

[Texian]

Hey John, Welcome to the forum. I love this place. Unlike in the U.S., their answer to every question is not always to just go buy something expensive.

For reference, y'all, John is a big time, famous turner in the U.S.

[hughie]

welcome aboard John. :2tsup: we're a irreverent mob, but we mean well :U

[John Lucas]

I wouldn't go so far as to say big time or famous. I have a big mouth. Seriously though I work a full time job as a University Photographer but I turn as much as possible. I love to learn new skills which is why I am trying to learn all I can about thread chasing.
I do find it interesting that whenever you ask a question on some sites they always tell you to buy the most expensive gadget on the market. People will be new at turning and asking about a starter lathe and someone will invariably tell them to buy a $6000 Oneway. If they were on my income they would not think that. :)
I just wrote an article for Woodturning Design magazine on how to make your own thread chasing tools. I don't know when it will be published. He's had it for a while and hasn't sent me a copy to proof read.
I looked last night and I have 3 sets of 20TPI thread chasers. One set I picked up at the flea mkt, one Sorby set and one set I made myself. I have a theory that the angle of the thread chaser affects the speed that the tool travels which in turn affects how slow or fast your lathe has to be to give you the time to cut the threads and not run into the shoulder. I say this because my first hand made tool was a 16 TPI chaser and it moved really fast and was hard to control. I changed the angle of the teeth and it slowed down. I'm going to try and measure the angle of the 3 different chasers and if they differ then I will try to cut threads with each and see if I'm correct or it was just a fluke from an inexperienced chaser. I'll let you know.

[JanHovens]

Hello All,

I am also new to this forum. I live in the Netherlands and do a lot of woodturning. I also give demo´s and teach other woodturners my speciality, thread chasing. I make my own chasers by milling the teeth on an old toolmakers mill. I use bar stock C45K (waterhardening). To John: The angle is of no influence what so ever . Thread chasing can be done on a lot of woods. All the fruitwoods are very good material. All the maples will also give a good thread, even the soft maple´s. All it takes is practice, practice and more practice. With te softer woods I use ordinairy sunflower oil (stolen from the kitchen) as a kind of lube. In collaboration with a German firm I have made a DVD on thread chasing. Unfortunally only in the dutch and german language. An excerpt can be seen on You Tube under : Thread chasing. I have put another ( not to good) movie on You Tube wich involves thread chasing on bone: A bone pawn.
Greetings,

Jan

[John Lucas]

Jan Just checked out your video on Youtube. I couldn't get any sound. Still it was interesting. I could learn a lot from you I'm sure. I'm going in the shop tonight and practice a little more.
I poured some epoxy into slots cut in my soft wood blanks. I want to thread the epoxy and see how good it goes. I don't have access to wood that is good for hand chasing. I can get some hard maple but don't have any right now. The hard woods that I've purchased are still probably partly green so I won't be able to use those for quite a while. If epoxy works I can use that today. I have chased threads in PVC but it's hard to find the right sizes and I don't know what glue to use to hold it in the wood even if I did find the right size.

[JanHovens]

Hi John,

Sorry there is no sound on this piece. Would not help probably because it is in German. You can practise on wet wood but I grant You You can only make a good fitted lid on a box with very dry wood. May be You can beg steal or borrow from a woodturning friend? :U

Greetings,

Jan