Pewa use

[William Rogers]

I just pulled a large walnut bowl from a bag drying for multiple months. The bowl is 15” diameter. Haven’t had much luck at all drying walnut using a bag and of course this one has one crack from the inside to the outside. Normally it would go into the burn pit. However I have the pewa template and pewas. I have never done a pewa repair. Questions are is this a candidate for repair? If so, do you fill the crack on the inside or leave it open. I intend to leave the crack open on both the pewa side and inside.

Thanks



Outside crack


inside crack

 

[Neil S]

~
Can't comment on pewa in relation to calabash, but if I am using bow ties on my bowls I tend to fill the cracks with a contrasting colour to highlight the crack and make obvious the reason for the bow ties.

​

 

[Emiliano Achaval]

Yesterday I answered you on a conversation. I will copy and paste my response. Good idea to start a thread, this way more turners will benefit.
I would finish turning it. Looks safe. Then, when you are at 120 grit, put one or 2 pewa on the outside. I do not fill the cracks. Pewa do not go through. And only maybe on a platter, I would use them on the "inside" The reason I do not fill in the crack is that I try to make it look like an ancient repair.

 

[hughie]

I have a large slice of eucalyptus with the pith , natural edge, oiled etc with a couple of pewas to hold it together looks like I will need another. This sort of primitive fruit bowl is quite popular down under, irregular, hand carved and oiled. Its about 20" in dia by 4" or 50cm x 10cm

 

[Emiliano Achaval]

Something that I always say at my demos is that I never use a Pewa to hold the piece together. The blank has to be structurally sound. I don't think I would have turned that Eucalyptus blank with that crack, especially since they are so good as firewood, LOL

 

[hughie]

Something that I always say at my demos is that I never use a Pewa to hold the piece together. The blank has to be structurally sound. I don't think I would have turned that Eucalyptus blank with that crack, especially since they are so good as firewood, LOL

lol normally for me as well , but the DIL loves it, the secondary cut has opened up more. The other aspect is its very hard as its been down for a few years and very dry

 

[Pat Scott]

I'd put a couple pewa on it also, it's a tight enough crack and pewa are a good choice. I finish turn the outside, sand to 120, and then put pewa in before finishing the inside. I want stability (mass) while routing. If you finish turn the inside you can get flex while routing depending on wall thickness. This is more an issue when the crack extends through the rim than just in the sidewall like yours. It's impossible to put pewa on the inside of a bowl due to the size of template, router base, inside curve, etc.

Sometimes I fill cracks before putting in pewa, but remember a bowl doesn't have to hold water to be useful. That bowl can still be used for anything you want even with the crack.

I was told when a bowl cracks on the side like that it can be caused by the bottom being too thick. The rim wants to distort as it dries but the base is too thick and doesn't allow movement so the side splits. When roughing out make the base slightly thinner and don't forget to take the tenon thickness into account. There is very little movement in the base compared to the rim. If I have a 1" thick rim I make the base 3/4" for example.

 

[John Hicks]

I don't even know what a "pewa" is. Does that mean the repair smells?

 

[William Rogers]

I was told when a bowl cracks on the side like that it can be caused by the bottom being too thick. The rim wants to distort as it dries but the base is too thick and doesn't allow movement so the side splits. When roughing out make the base slightly thinner and don't forget to take the tenon thickness into account. There is very little movement in the base compared to the rim. If I have a 1" thick rim I make the base 3/4" for example.

That could be what happened to my bowl. Good advice I’ll remember. But I've never had much luck drying walnut in a bag. I’m hoping the next time I have better luck with my kiln.

 

[Pat Scott]

I don't even know what a "pewa" is. Does that mean the repair smells?

Pewa is the Hawaiian name for a Butterfly patch. I've also heard them referred to as Bowtie, Dutchman, Hourglass, Figure 8, and Dog Bone. You can see them in Neil's picture above.

 

[hughie]

I'd put a couple pewa on it also, it's a tight enough crack and pewa are a good choice. I finish turn the outside, sand to 120, and then put pewa in before finishing the inside. I want stability (mass) while routing. If you finish turn the inside you can get flex while routing depending on wall thickness. This is more an issue when the crack extends through the rim than just in the sidewall like yours. It's impossible to put pewa on the inside of a bowl due to the size of template, router base, inside curve, etc.

Sometimes I fill cracks before putting in pewa, but remember a bowl doesn't have to hold water to be useful. That bowl can still be used for anything you want even with the crack.

I was told when a bowl cracks on the side like that it can be caused by the bottom being too thick. The rim wants to distort as it dries but the base is too thick and doesn't allow movement so the side splits. When roughing out make the base slightly thinner and don't forget to take the tenon thickness into account. There is very little movement in the base compared to the rim. If I have a 1" thick rim I make the base 3/4" for example.

Pat this a large chunk of non descript gum tree, most of our gum trees are just fire wood. It was akin to flogging a dead horse this piece

 

[Pat Scott]

Pat this a large chunk of non descript gum tree, most of our gum trees are just fire wood. It was akin to flogging a dead horse this piece

Sorry! My reply was meant for the OP with the Walnut bowl. I hit the wrong reply button.