Filling in cracks?

[Dino]

Hi. Me again.

Just wondering what you guys use to fill in cracks? This is mainly for drinking goblets that I am making so I want to make sure that it is not going to poison someone.

I've heard that fine saw dust works but how do you keep the sawdust...in the cracks?

Thanks.

 

[Random Orbital Bob]

I reckon I've got my crack filling down to a fine art now. Here's my method.

Buy the CA glue from Poundland, cost = £1 for 4 little bottles.

2 reasons, 1) its cheap so you're not afraid to use it. 2) its runny (because its cheap) which means it really penetrate into the crack.

Go to your dust extractor and carefully scrape the incredibly fine dust off the filter (should be like talcum powder it's that fine) and stick as much in a pot you can get. Drip the CA in the crack, sprinkle that fine dust in (preferably colour matched from the very wood you're turning) and wipe carefully off after a minute or so keeping the dust in the cut so to speak.

If the cut goes through (like a narrow neck on a vessel) mask the side it would drip out of before you pour the glue.

 

[Dino]

Bit of a problem...I don't have a dust extractor. All my shavings go on the floor.

I'm looking to get one as soon as I can but right now I can't really afford it.

 

[Random Orbital Bob]

right then....just the finest dust you can find instead. If you do a sheer scrape on the project. collect the dust that settle on the toolpost and/or beds, that's always very fine. You just want dust rather than shavings because they pack into the crack better and soak the glue up which sets as hard as the wood and can be sanded just fine.

For really small fissures after the projects off the lathe, I also use those coloured wax sticks and match as best I can.

This is one of the tricks to turning timber that hasn't finished seasoning ie it frequently opens up with some cracking

 

[Spindle]

Hi

If the vessels are going to be used for food and drink I'd shy away from stock with cracks or shakes preferring a sound basis on which to apply the finish / seal.

For filling voids in general I use a variation of the method described above in that I tend to use epoxy rather than CA - it takes longer to cure but I feel it provides a more resilient filler and as such can be used to address larger voids.

Edited to add: I often use dust from my band saw, it tends to collect in the corners inside the cabinets, mix dust with epoxy to form a paste and apply to the void.

Regards Mick

 

[Dino]

It's only a small crack. I'll have to get some CA glue then. I have no idea where the closest poundland to me is, so that should be interesting.

Thanks for the advice.

 

[Rhossydd]

I have no idea where the closest poundland to me is, so that should be interesting.

Just any cheap CA adhesive, superglue is fine. Don't spend money more money than you save travelling to get any, your local corner shop will have some.

 

[Dino]

If superglue is fine I'll check the corner shop.

Would PVA glue work? I've got a ton of that.

 

[Phil Pascoe]

People used PVA for decades before CA came on the scene.

 

[Random Orbital Bob]

pva does work but the setup time is much longer. The value of CA is that it goes off really quickly and even more so when mixed into a wood dust paste. With pva, it will also go off quicker when pasted but you can't really fill, wipe and return to work like you can with CA. You would need to let it set for, I dunno at least an hour or two I'd say and that's in a decent temperature.

I've used pva for years on my normal wood working projects for cracks etc but I always use CA on the lathe for the speed.

 

[Bodrighy]

This sort of thing?

I use brass, aluminium or copper powder or, as mentioned various dusts from sanding. I fill the crack with the dust and then dribble the runny CA glue into the crack. Sand back and repeat if needed to fill any bits missed. I find if you put the CA glue in first the dust can stick to the surface but not fill the crack. If you are using dust you can also mix it up with epoxy and fill the crack but IME trying this with metal powders leaves an unsartisfactory finish.

Pete

 

[Dino]

That's exactly what I am looking for Pete, thanks.

As I have a lot of PVA and am not in a rush I'll use that for now, and I'll go about getting some CA glue incase I ever am in a rush. The metal powder is also an amazing idea which I hope to try one day too.

Thanks a lot!

 

[Grahamshed]

That certainly seems effective Pete. Lovely vases.

Can you get CA and separate activator spray here ? it would give you a bit more play time.

 

[Random Orbital Bob]

yes Graham...commonly available.
Pete . do you use the metal powder for the pigment?

 

[Spindle]

Hi

Activators reduce the curing time of CA - water mist will also work.

Regards Mick

 

[Bodrighy]

Using the metal powder with super glue leaves you with what looks like solid metal. Using it with epoxy has, for me, always looked like a sort of plastic finish.

Pete