Thread: Tap and dies for wood

Bilco, since this thread was last active (9 years ago!), there've been a few more developments in the wood-threading field.

Something you might like to consider is "primitive" way of making a tap, which I first saw in one of the very early issues of Fine Woodworking. That would have been close to 40 years back & may not be available to you.

AWR published a couple of articles I wrote on making the tap and a matching router-operated jig to cut the associated screw threads:
• Making wood screw threads, part 1 92:48
• Making wood screw threads, part 2 93:80

I used a different method to lay out for the kerf on the shaft of the tap that drives it at the required hread pitch, which I think is easier & more intuitive than the method in the original article. Magazine articles are necessarily briefer than you'd like, so if you are interested in giving the method a go & have further questions, fire away...

If you like to see action rather than read text, they videod me demonstrating the tap at a woodshow, here and there's a slightly more professional video of the router screw-cutting jig in operation here

There are quite a few other videos on Yewtoob of various people threading wood in various ways..

Here's one I particularly like, re-engineering existing material to make a tap - no lathes were injured in the making of this one!

There are at least a couple more simple ways of making taps that I know of, & likely more that I don't, but the method described above has been around for several centuries & works well. You do need a wood lathe to turn the blanks, but I assume you will have one if you intend making wooden screws. You can make the blanks for screws without a lathe, of course, but it's a lot more bother.

It takes a few moments longer to tap each nut by the 'primitive' method compared with driving a metal tap though in a single pass (which can be a very good workout with a big tap in hard woods!), but if you are only intending to make a few screws for a bench or "moxon" vise, that's neither here nor there. One advantage of the multi-pass method of tapping is that you can easily go back & take another pass if your nut gets a bit tight when the humidity increases.

Making wood screws can be lotsa fun & they are remarkably durable & useful.....
Cheers,

Ian thank you very much for your reply with the detail and links.

Originally Posted by IanW

I used a different method to lay out for the kerf on the shaft of the tap that drives it at the required hread pitch, which I think is easier & more intuitive than the method in the original article. Magazine articles are necessarily briefer than you'd like, so if you are interested in giving the method a go & have further questions, fire away...

OK I'll bite That's the one piece that the vids (which were *GREAT* by the way) didn't cover, since you needed that as the first "missing ingredient" so you could execute the remainder of the process !

Originally Posted by poundy

OK I'll bite That's the one piece that the vids (which were *GREAT* by the way) didn't cover, since you needed that as the first "missing ingredient" so you could execute the remainder of the process !

Fair enough Poundy, that definitely isn't covered, but there's a limit to what you can do in a 4 minute video. It is explained in the article in AWR. I agree with you entirely, that it's key to the whole process. In the FWW article I read way way back, the author marked off the thread intervals along two sides of the tap shaft,iirc, then used some masking tape wound round the shaft to indicate where the kerf should be cut. It looked rather hit & miss to me, so I came up with the method I explained in the magazine article. I think you'll grasp it easily if you have access to the article, but if you can't get a copy, maybe I can post a pdf here to explain it...

Cheers,

I'm either an idiot or I can't find a way to buy their back issues... so I am "absent" any detail, unfortunately...

Hmm, looks like they don't do paper copies any more, just electronic copies. Leave it with me & I'll see what I can do...

Cheers,

Righto poundy, I did some searching & I couldn't figure out how to get back copies either. So I contacted the editor & this is the answer I got:
... Back issues are available for the same price as the current issue, $11.95.
If your friend would like to buy issues 92 and 93 he is welcome to get in touch with our Customer Service Manager, Martin Phillpott <[email protected]> ..

Seems a lot to pay for a couple of articles - does your local mens shed keep copies? Library? A photocopy costs just a few cents...

Cheers,

The Zoom Zoom method .


Robert Brown on Instagram: “Cutting 62 mm diameter Beech bench threads and some Oak nuts . With some sizing done on the Wadkin RS tool carriage .”



Rob

Originally Posted by auscab

The Zoom Zoom method .

When you posted that a few weeks ago I wondered whether I should have commissioned you to make me some The lathe absolutely was a cheat step, no doubt. But anyway I really was interested in the design process end to end, because if I want my screw thread to be 47mm not 50mm, then I just want it to be.... not that I do, that's just weird, I know, but still, choices.... everyone would make it 48mm, right? yeah, thought so....

Originally Posted by poundy

When you posted that a few weeks ago I wondered whether I should have commissioned you to make me some

Im doing a few for me and just ironing out the method with a few first. PM me though if you need some done .

Originally Posted by poundy

The lathe absolutely was a cheat step, no doubt. But anyway I really was interested in the design process end to end,

Cheat step ! lol . Whats cheating about a better way .
I'm amazed at that lathe . I actually said to a friend a year before I got that lathe that my currant Wadkin back then, without the tool carriage was good enough because what could the tool carriage be good for ? I do furniture and no turning for furniture is just a plain straight cylinder. Its all shaped and curvy work . I hadn't thought of this though with the tool carriage . The use in doing a straight cylinder for a thread.

Originally Posted by poundy

because if I want my screw thread to be 47mm not 50mm, then I just want it to be.... not that I do, that's just weird, I know, but still, choices.... everyone would make it 48mm, right? yeah, thought so....

Well these are 62 mm . And to me that's almost looking small for the proportions of a bench screw. Its not to small but I reckon 75 mm would be great to see, On a big grunty bench .

Rob

I reckon if I had a lathe with a tool carriage I'd be using it for sizing bench-screw blanks for sure! I haven't done a lot of turning these last few years and getting a bit rusty....

Looks ideal for larger diameter screw blanks, but I think it'd need a steady for smaller diameters like 3/4 handscrews though, which would probably make it slower than just using a skew.

What size to make screws is everyone's guess, it seems. I would agree that you should use at least 50mm for 'standard' bench screws, though I've used 1 1/2" on my 'portable' bench & they seem to be robust enough. The advantage of a larger diameter as I see it is not because it's more robust, but because you get more power for the same thread-pitch for the same speed of opening/closing. However, it gets a bit awkward fitting a very large screw inside a tail vise, for e.g. Apart from the confined space inside the 'jaw', there isn't a lot of room to make the nut in the cross-piece of the bench that fits inside the vise. I'm happy enough with the 2 inch screw in my tail vise, but a 3 inch might be the goods for a front vise where space isn't an issue.

It's a bit of a pity there are no agreed "standards" for wood threads the way there are for metal threads. Every maker of taps & threadboxes seems to have made their own arbitrary choices, plus the mix of Metric/Imperial. Repairing a worn/damaged thread down the track will be a challenge unless you still have the original taps & threadboxes. That's where the 'mediaeval' method shines, any diameter, any pitch you want - no problem.

You were crunching your way down that screw with apparent ease, Rob (or did you edit the sound of your grunting out? ). It was cutting very cleanly, too - what wood were you using?

Cheers,

Originally Posted by poundy

When you posted that a few weeks ago I wondered whether I should have commissioned you to make me some The lathe absolutely was a cheat step, no doubt. But anyway I really was interested in the design process end to end, because if I want my screw thread to be 47mm not 50mm, then I just want it to be.... not that I do, that's just weird, I know, but still, choices.... everyone would make it 48mm, right? yeah, thought so....

Poundy, I have the Beall 1½" thread kit if you want to have a play. I also have the ½", ¾" and 1" kit.

Originally Posted by IanW

You were crunching your way down that screw with apparent ease, Rob (or did you edit the sound of your grunting out? ). It was cutting very cleanly, too - what wood were you using?

Cheers,

Its a different thing from the normal hand chisel work of turning Ian . Where you go normally back and forward with a gouge to hog of the corners and get down more slowly close to where you want .

With this You can attack directly at the end grain and take a decent bite at it too just rolling along from right to left. The shaped HSS insert is 1x 1/2 x around 3" long'' and the depth I can go at it depends on how long the sharpened HSS tip is .
The wood on that one was Euro Beech . That and The Blackwood were pretty much the same .

The hand wheel and the gearing on these lathes can be read about

here Wadkin RS, RU & RUH Lathes


I just took this out of it .

"One popular accessory was a rack-driven carriage assembly, complete with a proper compound slide rest with a degree-engraved swivelling top-slide. The unit fitted to most models of the RS had a direct connection between the handwheel gear and rack - resulting in a rather rapid action along the bed - but the last models produced had a mechanism similar to that on the RU and RUH where (exposed) reduction gears that gave a much steadier and smoother drive."

That rather rapid action along the bed is noticeable . It wants to scoot along into the work and if your try to go slower its sometimes easier with two hands on the wheel to give a firmer slower speed . Just something I remembered reading about before I got to use the lathe and the tool carriage so I was waiting to see what it was like . I'm not complaining though . Its great .

Rob

Originally Posted by NCArcher

Poundy, I have the Beall 1½" thread kit if you want to have a play. I also have the ½", ¾" and 1" kit.

thanks NCArcher, very kind, I might in the future take you up on that. I wasn't actually after threads just yet, nor was I advocating that i needed 48mm, or any other dimension just that I wouldn't have minded capturing the ideas on how to create my own custom size / pitch for when I need them