Binding string removal when?

[BigPine]

Hi all. I'm on my first build, a 8013 using the hexrod taper. I have a Bellinger binder and I'm using Unibond 800. I have glued and sanded the butt section. I let it cure overnight and removed the thread by sanding it after a day or so. I carefully continued sanding with small sanding blocks, careful to stay on the flats and not over-sand it. I'm pretty happy with the results. I glued the sand paper to the blocks with 3M 77 spray glue.

I have 12 good tip splines ready to glue-up after going thru the planing/dry binding/measuring/adjusting/more planing/measure again steps. I'm concerned that I'll damage the delicate tips when I sand & remove the cured binding thread. Fully cured, the glue is pretty tough and the blank wants to roll around a bit on the bench.

I plan to wipe off the tip blanks after binding with a damp bit of tee shirt (wet with water) and remove as much of the extra glue as possible. My question is: Can I remove/unwrap the binding thread before the glue is fully cured? My shop is in the 65-75 degree range.

I'd sure like to wind up with a couple of usable tips sections when these steps are completed!
Thank You for any help or advice you can offer.
Jeff

[flyman219]

After I bind my rod sections I roll it on a sheet of painter's paper I have stretched over my bench (or you could use newspaper) to remove as much of the excess Unibond800 as possible. I don't wipe the shaft with a wet rag (personal choice to not chance a thinning of the glue). After that I place the shaft in a drying box set for about 85-90 degrees overnight. In the morning I cut the knot and remove the binding string from the shaft(s). If for some reason you can't peel off the binding string you might need to change your binding string choice. I had trouble with Kite string and bought a better choice that does not break as I peel it off. No problems now, Then the sanding of the excess glue only, no string to remove with the sanding.

Mike

[BigPine]

Hi Mike, and Thank You for the response. Sounds like you are able to pull the string off the glued section after the Unibond is fully cured. I’m planning to glue up these tip sections this weekend. Fingers crossed.
Jeff

[DonT]

If you end up needing to sand, you'll be ok if you carefully sand with all the strokes towards the thin end of the tip section. The glued up bamboo is tougher than you might think. FWIW, I sometimes use the tri-scraper that Golden Witch sells for this. I bought both sizes of the tri-scrapers when I got started and I have used them extensively in the first stages of finishing out the glued up blanks and also for removing old wraps.

[BigPine]

Hi Don. Using a tri scraper is a great suggestion. I have a woodworking scraper (hook edge type) but I’m not really very comfortable with it. The tri scraper is much easier to keep parallel with the hex flat. Thanks, I’m gaining more confidence to get er done!
Jeff

[BigPine]

I finished the glue up for my first three sections, and they turned out pretty well. I glued them up in the early evening and pulled the binding string in the morning using a section of PVC pipe to hold the section while pulling the string off, all smooth sailing. Then I let the glue cure for another day, and followed with some careful sanding with a few small sanding blocks. The images still show some glue remaining on the tip sections. Each section went a bit smoother as I got my groove down. I also slowed the glue set time using a 5:1 ratio (shop @ 65-75*). Thank You for the advise here, and I'm gaining some confidence.

[Tommasini]

The only thing I can add is to give the strips several minutes to let the Unibond 800 glue soak into the bamboo before closing and binding lest you risk starving the joints and having some delams when turning ferrule stations or trimming the tips.

[canerodscom]

The only thing I can add is to give the strips several minutes to let the Unibond 800 glue soak into the bamboo before closing and binding lest you risk starving the joints and having some delams when turning ferrule stations or trimming the tips.

Good advice tommasini. I also very lightly mist the strips with water before spreading the glue, then spread that water with a dry foam brush. Especially if I’m flying relatively soon after heat treating.

Harry


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[BigPine]

New comments above noted! With glue and string and tacky fingers, thanks again.
Jeff

[dorenac]

The only thing I can add is to give the strips several minutes to let the Unibond 800 glue soak into the bamboo before closing and binding lest you risk starving the joints and having some delams when turning ferrule stations or trimming the tips.

Over the years with the advice of a good friend from Switzerland who is a master joiner, I warm, not heat, the splines prior to applying West System epoxy. According to my friend the warmth promotes epoxy absorption. Similar concept to Tommasini's but with heat added.

[BigPine]

Thank You for your suggestions, all.
Tight lines, Jeff