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[Chief Tiff]

Try this one as well; it's from 1929 so has more emphasis on what would have been available to the average hobbyist around hat time; eg using old files where now you can pick up dimensioned HSS very cheaply.

[IanW]

Try this one as well; it's from 1929 so has more emphasis on what would have been available to the average hobbyist around hat time; eg using old files where now you can pick up dimensioned HSS very cheaply.

That's the Starr article from FWW that Jeremy pointed to in post #14, CT. The quote is from 1929, (FWW didn't get off the ground 'til 1976....)

Making the cutter for the traditional style threadbox Starr talks about is the key to the whole thing. They really need to be tough, which means either grinding it out of a chunk of very hard steel, or starting with annealed stock, doing the bulk of the work in that state, then hardening before a final honing. It has to be spot-on, or it simply won't work. I spent many frustrating hours trying to make a threadbox after reading that article, and produced about 100mm of pretty poor thread!

Some day I'll get one of these gadgets to work for me, just for fun, and because I hate to let something beat me, but when a second FWW article, a couple of years later, showed how to make a threading jig for a router, I promptly lost interest in threadboxes. I made one up & it worked beautifully first go, which was mostly luck, as I discovered when I set it up next time. However, if you take a bit of care, and persevere, it eventually comes together and you are off & running. With a carbide bit like I have, you can cut miles of screw thread - you'll run out of suitable wood long before the bit is dull!

So if you just want to make a few bench screws & get on with it, a threading set-up similar to what I use is just so much easier to make & to get working, and can cost you nothing. It's also quick, once you get a bit of practice - that pile of bench screws in the lead pic for the article in AWR was probably a couple of day's worth of work, including turning the blanks, the actual threading takes a few minutes per screw, once you get the set-up working. Because I do so much threading, I use a solid carbide bit that cost me $25 at the time ($34.50 at LV, now) but in the article, I've also shown that an old 1/4" HSS twist-drill bit ground to 60 degrees (with a bit of relief) can do the job perfectly well. On a test-run it made at least one screw for me and was still cutting ok. The rest of the jig is made from scrap wood, so the only expense is for a couple of hefty wood screws to hold the two parts of the jig together, and you probably have what you need in your tin of odds & sods screws (that we all have in our sheds, don't we?).

Cheers,

[Chief Tiff]

That's the Starr article from FWW that Jeremy pointed to in post #14, CT. The quote is from 1929, (FWW didn't get off the ground 'til 1976....)

Oops; didn't spot that part, just noticed the date and assumed it referred to the article.

At the time I was going to make a cheeky comment suggesting that you may have read the original article when I thought it was first published; now I know it's a distinct possibility

Hopefully my copy of AWW is waiting for me at home so I can have a crack at making a similar one; you took me through the operation of yours at the Brisbane TWWW show and I was quite impressed at how simply it could all be constructed. I just happen to have a spare Chinese 1/4" router that doesn't have much of a purpose anymore so I can dedicate it to this.

[HUON]

Ian, good article on your wood screws. Many thanks.

[IanW]

Thanks, Huon. There is a video that was supposed to be posted when the magazine came out, too. Doesn't tell you anything extra, but it does give you a good look at the jig being set up, & in action.
I've had my copy of the mag. for nearly a week, now, but can't see the video on AWR's site. I've just asked the editor where it's at, so when it gets up, I'll post a link...

Cheers,

[HUON]

Ian, what are your thoughts on a 60 deg v groove router bit for cutting the threads on the timber screws.
Cheers.

[IanW]

Ian, what are your thoughts on a 60 deg v groove router bit for cutting the threads on the timber screws.
Cheers.

Hi Huon, that's essentially what I use, it's this one, that Lee Valley sell for the Beall threading kit. It has little 'wings' on the sides of the V & usually makes very clean cuts in just about any wood, and being carbide, it stays sharp almost forever.

Any 60 degree bit will do the job, but a straight 1/4" job is easier to fit into your jig & set up & will suit for any thread pitch down to about 3 tpi. The screws I made from the tap described in the AWR article are 8mm pitch (3.175tpi), and my 1/4 inch bit was just up to the job - had the thread been any coarser, it wouldn't have cut a wide enough groove.

If you don't already have a suitable bit, & only want to make a few screws, there is no need to go to the expense of buying a bit you might hardly ever use again - just take an old 1/4" HSS twist-drill bit, chuck it in your battery drill & spin it against the (spinning) grinding wheel to put a 60* point on it. I pre-cut a 60* notch in a piece of cardboard & use that as a template to check as I go. Once you've got your angle, take it out of the drill & grind some relief behind the cutting edges. Easier to do than you may think and works a treat. I tried one out on reasonably tough stuff and it stayed sharp enough to cut at least two big bench screws...

Cheers,