Hairline Cracks

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LDF Knives
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Hairline Cracks

Post by LDF Knives » Sun Jun 28, 2020 8:59 pm

What's a good way to fix a Hairline crack on a Boker Barlow delrin on the bottom? clear glue and touch up?

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Doc B
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Re: Hairline Cracks

Post by Doc B » Sun Jun 28, 2020 10:03 pm

Zap-a-gap...comes in various viscosities. It is a cyanoacrylate glue and very strong, for cracks. This is the thin viscosity that I apply with a toothpick. If needed, afterward, you could lightly sand. ... UTF8&psc=1
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Re: Hairline Cracks

Post by orvet » Sun Jun 28, 2020 10:31 pm

The thin Zap-a-Gap is what I use for hairline cracks like that. I start out with alcohol in a syringe, preferably with the needle so you can get it into the tight spaces and I squirt the alcohol into the crack and between the liner and a handle if possible. Then blow out the alcohol with compressed air.

The thin Zap will spread out pretty well down into the crack and even under the handle sometimes.
I usually use a drop the thin on the first application so there's plenty of it to run down inside the crack. Wait a few seconds and then wipe off the excess before it dries. I will add additional thin coats of the thin until it fills in the crack. If the crack is a little too wide for that I will finish the top of the crack with the medium Zap.

If you do get some glue on the handle, it is easy to wipe up before it dries. After it dries it's a little tougher but if you have a CA debonder that can clean up the surface. Just be sure you don't get it down into the crack are you can soften the glue that you already have in the crack.

After the glue has dried if you need to sand some of the excess off you can also do that and you can polished the bone handle on a buffer as well. If you don't get too heavy-handed with the buffer and get the bone too hot, it should not affect the glue.
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