cyanoacrylate glue

[Mark Rainey]

Chipped off a piece of mahogany about one inch long by 1/8 inch wide by 1/4 inch deep, so of like a big sliver. Used Starbond super fast thin ca glue - it flows like water. Stuck the piece on and taped in place for 20 minutes. When I stressed the piece it came loose. Still seemed sticky. The ca glue works for me sometimes, other times the piece just falls off. Am I using too much? Stessing too soon? Are there any techniques I am missing?

[Kevin Jenness]

Ca glues cure by reaction to small amounts of water in the joined material. If your wood is very dry that may not happen or take a long time. Thin formulations may wick into the wood and starve the joint. Try using an accelerator and medium viscosity glue. You can put glue on one side of the joint and accelerator on the other or just glue the joint and spray accelerator over it.

[Brice Rogers]

Starbond comes in a variety of thicknesses: thin (like water), medium, and thick (a little goey). Kevin Jones may be very correct that the like-water CA soaked in. Try the medium thickness stuff.

[Mark Rainey]

Thanks for the info Kevin & Brice.

[Mark Bolton]

Also remeber that CA is extremely brittle when cured so you cant expect much from it. A lot of people seem to look at it like a miracle cure all but you may well have been better off to use pva and clamp. 20 mins is only 10-15 minutes shy of good for pva.

[Robert Engel]

I've had the same experience. I use the medium thickness, never thin.

But in most cases I prefer to use wood glue b/c it is more reliable.

I use CA reluctantly when I need an instant repair or I'm done for the day.

[Kevin Jenness]

Mark makes a good point. I mainly use ca for small repairs where clamping is difficult or for filling small checks, occasionally between two strips of blue tape for workholding.

Many turners do use it successfully to attach green blanks to glue blocks on faceplates.

[Mark Bolton]

I keep it for the blue tape method a lot as well but those are typically lots of surface area scenarios. Ive had the same issues with trying to cheat with it on repairs where its just not well suited. All you see on the tube is everyone and their brother putting everything together with a drop or two and a spritz of accelerator... Not been my real world experience at least. It reminds me of the 70's ads for Krazy glue with the guy gluing his hard had to a steel beam. Deceptive advertising. Large surface area, smooth surfaces. Smaller surface area/odd parts, it may stick them together if you are to never touch them again but anything that is going to see some strain/movement, the stuff is close to glass hard when cured.

P.S., the bummer is when you try to cheat with CA on a splintered off part or some fractured repair and the CA doesnt do the trick youve roached any potential for another repair other than epoxy. Its kind of a one shot deal especially with wood as you can never get it off to revert to the repair you should have used to begin with.


https://www.youtube.com/watch?v=sZB7sO5ZoV8

[Mark Rainey]

Good practical information Mark, Kevin, Robert. Thanks

[Zachary Hoyt]

I only use CA for non-structural type jobs, like gluing inlays and dots into holes. In these cases there is no mechanical load pushing on the glue joint, it's just fighting a very tiny amount of gravity if the instrument is turned upside down.

[Grant Wilkinson]

If the size of the piece that chipped off, and it's location, make it difficult to use pva and clamps, you can use both CA and pva. I do this frequently when pieces want to slide around on me. Spread the pva leaving a small space clean. Put a dot of CA medium at that spot. Spray accelerator on the mating piece and press the chip in place. The CA will bond it immediately and the pva will cure to form the more permanent bond. You can use the same procedure using CA and epoxy.

[Kyle Iwamoto]

If the size of the piece that chipped off, and it's location, make it difficult to use pva and clamps, you can use both CA and pva. I do this frequently when pieces want to slide around on me. Spread the pva leaving a small space clean. Put a dot of CA medium at that spot. Spray accelerator on the mating piece and press the chip in place. The CA will bond it immediately and the pva will cure to form the more permanent bond. You can use the same procedure using CA and epoxy.

Wow! Good tip!
Thanks!