DrPhill wrote:
Thank you Loren for taking the time to write that all out.
Some notes:
- I need to find my calipers to do the measuring
- Barge Rubber Cement? I dont recognise the term. A search on the web shows this to be the sort of thing that rubber soles are stuck to shoes with.... does this match your impression? Ah 'Barge' is the manufacturer. 'Rubber Cement' it is then.
- The superglue idea is an interesting one, sort of a primer?
- A butt (flush) joint may well be easier than a tapered joint. Maybe I could do a (45 degree?) slope on the butt joint so that it does not point directly down the whistle.
- How large a gap should I tolerate between the ends of the cork if I do a butt joint? I could fill any gap with glue, I guess.
- If my first attempt is less durable then I will get more 'opportunities to improve'.
Yes, caliper measurement would be good. Maybe transfer that to paper or cardboard to make a full length template and cut the cork from sheet on the template.
You are correct, Barge is the brand, I should have been more clear on that, sounds like some
sort of marine/boat thing otherwise, lol.
Superglue does act as a sort of primer: Evens out any uneven areas due to wood grain and gives a consistent surface for the adhesive to grip. Also helps save wear and tear on the wood underneath when it comes to remove or replace the cork next time as getting cork off sometimes involves scraping and prying. Many instruments we made and/or worked on were 30, 40 or more years and had been re-corked many times. The wear and tear can add up, so it’s worth taking some preventative steps.
Don’t cut the ends of the cork at a 45 degree angle, stick with 90 degrees/square ends. Remember rubber cement bonds instantly ( guess that’s why it’s also sometimes referred to as contact cement

) so you’ll have very little margin for error when applying the cork. This is important because it’s critical that you start applying the new cork dead even and going completely straight in the cork slot, otherwise problems will arise. Having the ends cut square is the only way you can’t really properly line up the cork and start applying it. I should have mentioned that you start by putting just one end of the cork in the slot, and then gradually/slowly/carefully work the rest of the cork in along the slot taking care to keep it even and flat in the slot the whole way. As I said, the rubber cement is unforgiving, so you do need to get it right the first time.
I should have also mentioned the following: Use a thin, light coating of rubber cement on the cork slot
and sides, a thick application works less well. Also use a thin application on the cork strip to be applied to the slot. Let the first application of cement to the cork dry, then do a second application of the adhesive, again a thin/light coat. The slot does not get a second coat. The cork adheres much better this way.
How much gap where the butt joint happens? As little as possible

strive for perfection! But, don’t worry too much if you have a small gap, as long as your instrument doesn’t leak air while playing, the gap won’t be a big deal. Stuff can build up in the gap and eventually start causing the cork to lift off, and the exposed ends can grap on the socket a bit while assembling/disassembling which can also start to pull the cork off, these are the main reasons you don’t want a gap. If you get the gluing and mounting of the new cork right though, it should resist a fair amount of that stuff and still last a decent amount of time. Maybe
Last item: After the new cork is mounted and the cement has been left to fully cure overnight, you will likely need to do some sanding of the cork to get the proper fit. Grease the cork very well all around (cork grease or Vaseline) and then try gently inserting the tenon into the socket while twisting. If the socket does not have a wide metal band reinforcing the full length of the socket the it is imperative that you do not force a tight fitting cork into the sock, it will likely crack the socket! If it seems like the fit is significantly tighter than before the re-cork, stop and sand the cork down concentrically a little at a time pausing frequently to re-grease and fit test. This can be a little frustrating and time consuming but you don’t want a cracked socket or a new cork sanded down so much that you have to remove it and start over.
I should mention that its often worth sanding a little taper or bevel on the side edges before attempting the first socket tenon marriage with the new cork. Reason being that you don’t want that side edge of the cork catching on the side of the tenon, which can instantly, or over time, cause the cork
to lift off at the edge. Also, having the cork edges slightly lower than the main body of the cork can help in thenfitment fine tuning as a completely flat cork can lead you to believe it needs more sand than is actually necessary, to the point where once you sanded the whole cork down enough for the leading edge to fit without binding, you now find the entire fit is too loos. So, just take a little off at least the leading edge (the side that will be inserted into the socket first), or do both edges if you prefer, prior to making any full cork sanding adjustments to fit. Don’t take too much off the edges though or you’ll end up with a wobbly connection.
So there, super easy, really nothing at all to doing a good joint re-corking

Have fun and let us know how it turns out!
P.S. Please forgive any typos or spelling errors, I would normally proof read but I’m short on time so....