Threading tenons

[Thalatta]

Does anyone know how to put thread on the tenons? I just wrap it round but then at the end don't know what to do other than tie a knot... and it looks like a silly knot.

Also, should I grease the whole length of the thread before wrapping it around the tenon and tying it?

Finally, I just bought a little silk thread only to find that people recommend polyester... What kind of thread should be used? I have an old 8 key English flute.

Merci buttercups!

[Jon C.]

Does anyone know how to put thread on the tenons? I just wrap it round but then at the end don't know what to do other than tie a knot... and it looks like a silly knot.

Also, should I grease the whole length of the thread before wrapping it around the tenon and tying it?

Finally, I just bought a little silk thread only to find that people recommend polyester... What kind of thread should be used? I have an old 8 key English flute.

Merci buttercups!

Hi,
what I do is use a little shellac on the tenon first then lay down a couple of layers, wax the thread with bees wax do some more layers, keep checking the fit, this also compresses the thread in the wax. when I am happy with the fit I will do some half hitches, then pull on the thread and bury the end, wax and grease. Silk is the best, polyester is cheaper... Make sure when you are fitting it that you don't put to much pressure on the socket, as it will crack! and that is a bummer...
Good luck!

[Thomas-Hastay]

Use one or two "clove hitches and cover the thread with cork wax, not cork grease

http://cache.eb.com/eb/image?id=63125&rendTypeId=4

[Thalatta]

Thanks guys, both messages above, that's really helpful. And the drawing is cool. I hesistate still however between cork and thread simply because where I live (in the Alps!) it's hard to get my hands on cork wax etc.

[jemtheflute]

Hi Thalatta, and welcome. Like many of your recent queries, there are plenty of old threads (pun taken advantage of! ) on this topic. Do check out the forum search facility. I know I've described my methodology here before somewhere. Here it is again:-

Thread Joint Lapping – a quick guide


Traditionally joint lapping is done with a loosely spun linen (flax) or hemp thread, waxed before or during application. If you can get it, use it. Bagpipe makers seem to use it and have no trouble getting supplies, but I have never been able to find a reliable source of such thread – the linen threads one can usually find at haberdashers are usually highly twisted, quite thick and hard “button threads” which are not suitable for this use. Apparently (though not unexpectedly) it is not immune to swelling with moisture, according to a bagpipe website I perused recently. Therefore, for many years and with good success (and no ill effects to any flute) I have used embroidery “silk” thread – actually pure cotton. This is readily available in an infinite variety of colours from any haberdasher. The only drawback I have ever found with it compared to linen is that it is less durable – a frequently used joint will need the lapping renewed every 3-4 years as eventually the thread wears out. I have never had problems with it swelling. It comes in small 8 metre skeins. The thread consists of 6 lightly twisted strands (themselves being medium twisted 2-ply threads). If you care about the finished colour, choose a colour several shades lighter than you’d like as the grease will darken it considerably

I proceed thus:

First, unravel the skein of embroidery thread and make sure it is tangle-free. Separate the six sub-threads into two groups of three at one end and split the entire length (being careful to run the twist out and not to tangle). An assistant to hold the ends you start from, or a door handle or nail on a wall or some such is necessary. Coil up the two triple threads around your hand (or wind onto a bobbin of some kind). Now you are ready for the flute.

Make sure all traces of old lapping have been removed from the tenon and clean it. Apply some cork grease (from any woodwind supplier/music shop) to the trough/combings on the tenon and spread it. Start to wind on the thread by laying the starting end diagonally across the tenon and, starting from the inward end, winding over it to secure it (the grease will help, but the first few turns are tricky). No tying or glue is necessary. Always hold the joint of the flute in your left hand and wind over the top of it away from you (i.e. clockwise around the tenon when viewed end on). Use moderate tension, but not excessive – you need the thread to seat firmly but not to constrict the tenon. If the tenon is “combed” (has turned grooves), start by laying a turn of thread in each groove systematically. If it isn’t combed, just lay the thread neatly side by side until you have completed one layer to the outer end of the trough/combings. Now apply a generous layer of cork grease and spread it around. Lay the turns of thread at the extremities of the lapping a little tighter than the rest as they have to resist the drag of assembly/disassembly more. Work your way back down the tenon with another layer, filling in the gaps if covering combing grooves. Now grease again and check how you are doing by test assembling the joint. Always hold the section in your left hand still and introduce the tenon to the mortise, twisting the section in your right hand over and away from you (in the same direction as the lay of the lapping thread) as you push the parts together.

It is unlikely on most flutes that you will yet have a snug joint, so apply more grease and add another layer, continuing to grease, test for fit and so on until you have built up a sufficient lapping. Be careful to keep the profile of the binding flat/cylindrical (unless the mortise tapers inwards, in which case you will have to work out the correct lapping profile by eye and test-fit) and test frequently. You want a snug, even, but not over-tight fit, that does not rock laterally. If you lay too much thread, just unwind it back beyond where you will need to finish and re-apply it spread more widely – the last layer/turns need not be laid completely systematically side by side but adapted to achieve a good fit in the mortise socket. You can add thread to just a little beyond the point where the joint assembles easily as it will compress a little over the first few days of use, but don’t make it excessively tight or you risk cracking the socket. Never force a joint together with more than moderate firmness! If it won’t twist on with only moderate resistance, take some thread off. Check the surface is even and not convex or concave by observing the grease on the surface – if it doesn’t soak into the thread evenly, or if the joint rocks when assembled, you need to unwind some thread and re-lay it. Be liberal with the grease, and continue to be so for the first couple of weeks as the thread will continue to absorb it.

To finish the lapping, you need do no more than grease the end of the thread down when you are satisfied with the fit. Try to have the final turns of thread towards the middle of the lapping. Should you need to remove or add some thread as the joint settles, you can just scrape up the end with a fingernail. It is unlikely to start to unravel, especially if you assemble the joint correctly as described above (never twist against the wind of the thread). If you need to add more thread after cutting an end, the best thing to do is to unwind about 50cm of thread, cut it off and start laying on a new, longer piece, binding over the ends of the old and new pieces as you did at the start.

When you have a completed lapping you are happy with and that has settled in for a week or two, you can do a more permanent finish if desired by unwinding about 50cm and rewind it laying the last 6-10 turns over a looped spare piece of thread with the loop pointing towards where the lapping will finish, then put the end of the last 5-6cm of your working thread through the loop you have bound over and carefully pull on the other ends (held together!) to draw the working thread-end under the last few turns of the lapping – pull it clear and tug it tight, then cut it off flush. That won’t unravel, but isn’t easy to adjust! (I don’t usually bother to do this any more.) A mid-way alternative – more secure than a free end but less so than a whipped-over one - is to lay in two half hitches in the last couple of turns of thread, making sure they lie in the same direction as you were winding.

Good luck!

(P.S. I didn't write this anew for this thread - it's a text I had saved on my computer. )

[deisman]

Here is a link to a pictorial. Works for me & seems authentic.

http://www.robertsnider.com/Kavals/Lapping.htm

Best,

Deisman

[Jay]

Here is a link to a pictorial. Works for me & seems authentic.

http://www.robertsnider.com/Kavals/Lapping.htm

Best,

Deisman

Nice illustration, but don't use cotton embroidery floss like the link suggests! I believe I've read on this forum a number of times that cotton will swell with moisture and cause the tenon to stick inside the socket. Am I right about this?

Jay

[jemtheflute]

Nice illustration, but don't use cotton embroidery floss like the link suggests! I've never used thread, prefer cork, but I believe I've read on this forum a number of times that cotton will swell with moisture and cause the tenon to stick inside the socket. Am I right about this?
Jay

Not in my experience, Jay - have you read my last contribution? (I haven't perused that link, so I'm not sure what thread is advocated there, though.)

As long as it is loose-spun (NOT a hard spun sewing thread) and well greased, cotton thread is fine. The traditional flax (linen) or hemp thread is just as likely to swell when soaked. Sure, so can cotton, if you don't treat it properly for the purpose, but do so and lay a good lapping correctly for a snug but not tight fit and all should be well. You would soon notice if there was any significant swelling of a new lapping and can easily remove some thread to adjust if you leave the end free as I suggest above. It is advisable to check a newly laid lapping frequently during playing, say every 15 minutes while it is new and settling in, for say a week or so, and be sure not to leave the flute assembled. I'd say the same for cork.

I have used the method and materials I describe above for 20+ years on my original R&R and other flutes with no deleterious results or problems. I have to renew the upper body lappings about every 3-4 years as they get assembled/disassembled most. The lower body one into the foot is rarely taken apart (they stow assembled in the case) so gets less worn/disrupted on the surface. I do recommend very liberal greasing of the thread during laying on the lapping (helps to keep it in place and tension even too) and ongoing regular greasing - with normal music shop "cork" grease. Modern synthetic threads might not swell when wet, but are far harder surfaced raising possible risk of socket erosion. Tight spun threads of any kind are harder to lay evenly, and I don't think you can get loose-spun synthetics very readily, if at all.

[Jay]

Didn't take the time to read through your entire thread, Jem. I'm at work today. I read enough to decide it was worth saving and did a quick cut and paste for later though...

Thanks for clarifying this. I like the idea of being able to unwind a bit to take the tension off a tight tenon. Can't do that with Cork.

Best,
Jay

[jemtheflute]

Fair enough!

It is worth mentioning that, of course, as with anything organic including most other parts of a wooden flute, significant changes in ambient humidity may affect the fit of a thread lapped joint. Both the thread lapping and also more significantly the wood and therefore the dimensions of the tenon and socket can fluctuate with changing conditions. You may need to remove some thread or add a little (or use e.g. a cigarette paper) after a few days when travelling between different climatic zones, or even at home between seasons. This is why I no longer routinely whip-finish my lappings.

[Doug_Tipple]

This is why I no longer routinely whip-finish my lappings.

You mean you let your loose ends dangle?

[jemtheflute]

This is why I no longer routinely whip-finish my lappings.

You mean you let your loose ends dangle?

Well, Douggie!!!!!! When I'm at a loose end (rare), I'm probably apt to dangle......

Actually, I'm a dab hand at whipping, but these days I prefer to lick 'em & stick 'em .

Lapping it up !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[RudallRose]

put to (sic) much pressure on the socket, as it will crack! and that is a bummer

the single most obvious observation I've yet seen on this board!

I loved it.

(being serious....not mean)

[jemtheflute]

BTW, I don't often disagree with Jon C, but from experience I would avoid beeswax, at least as the top dressing..... I have used it in the past and found that it tends to build up rather with repeated applications and can go nastily tacky - actually ending up making a joint too tight, or just sticky, as it gets moisture and impurities permanently mixed into it - can cause the top surface of the lapping to come away, especially in cold weather, as it is more reactive to temperature than petroleum based greases...... proprietary cork greases can do this too, but do so much more slowly and have a lesser tendency to make a nasty plaque over the lapping.

[Doc Jones]

I use one of those wax toilet seals and manually pull the thread through it. You can get one at the hardware store.

While this is vastly less convenient and much messier than any other of the methods mentioned so far, I personally believe that it will improve your playing as you will be "suffering for your art".

Also, it's much fun to go into the hardware store and say "I need a wax toilet seal for my flute". The look on the guy's face is priceless. I usually say it several times without cracking a smile.

I need a wax toilet seal for my flute.

Your what?

My flute. I need a toilet seal for it.

You mean like a flute, flute?

Yeah, you know the kind you use toilet seals for.

Let's start over. You need a toilet seal?

Yup.

For a flute?

Uh huh.

Let's start over...

OK

You have a flute and you want a toilet seal for it.

Right

Is it a realy big flute?

No, a normal size toilet seal should do the job.

Wait, let's start over...

It can go on for a long time and is much fun.

Once you have the seal you simply follow these simple steps:

1. Have someone hold the thread while you pull it through the messy wax toilet seal.
2. Roll the gooky wax thread on a spool of some kind
3. wipe hands on pant leg.
4. Wrap thread around tenon of flute
5. Test tenon...too loose
6. Add more thread
7. Wipe gooky hands on pant leg
8. Test joint...too tight
9. Remove some thread
10. Wipe gooky hands on pant leg.
11. Test joint...too loose
12. Add some thread
13. Wipe gooky hands on pant leg.
14. Test joint...perfect fit but quite wobbley
15. Say bad words of choice
16. Change pants and take flute to local music store
17. Pay music store guy $5-10 per tenon to replace #@&%! thread with corks.
18. Return toilet seal to hardware store and tell the guy it didn't work for your flute.

Doc