White film appearing after finish applied

[John Leinemann]

hi everybody. A member of our group here in Kelowna says he has a white film ( in the photo some of it has been wiped away) appearing on a couple of his bowls and is wondering if anyone might be able to explained. The bowls are made from Padauk (sp?) and the finish is wipe on poly. He uses exclusively wipe on poly and he’s made other bowls from the Padauk and he has not seen the film appear before. Is it the finish? Or the wood?

 

[Richard Coers]

My guess is that he used satin and the satin flattening agent wasn't thoroughly mixed in. But since you didn't give that data, as I say, just a guess. Lacquer can blush from trapping moisture under the finish, but wipe on poly sets up slow enough that is not an issue.

 

[Aaron Harris]

Unrelated to your question, but there is a guy local to me who turns bowls just like the one in your pic: BoardstoBowls. We mostly sell our wares in different venues so I've only met him once and didn't ask, but if you look at the link you will see numerous variations on that straight, outward-flared wall design with that plug in the flat bottom. Not really my taste, as I am all about chasing that elusive perfect curve; I am just curious about the technique. Is it started from the bottom on a screw chuck and then the hole is plugged?

I don't get it. When I use a screw chuck as I usually do with platters, I screw it onto the top of the blank, finish the bottom, then chuck it into the recess to turn out all evidence of the hole, but different strokes for different folks, I guess. Anybody want to weigh in on this technique?

I remember getting some cloudy stuff like that when I tried to wipe on oil in very humid conditions, so residual moisture could definitely be the culprit.

edit to add: I've turned my share of padauk (even though I hate its noxious orange dust!), and I've never had an issue with it taking a TruOil finish (which is basically a wiping varnish). I'm pretty sure it's not the wood.

 

[John Leinemann]

My guess is that he used satin and the satin flattening agent wasn't thoroughly mixed in. But since you didn't give that data, as I say, just a guess. Lacquer can blush from trapping moisture under the finish, but wipe on poly sets up slow enough that is not an issue.

That does make a lot of sense Richard… I’ll have to ask him what type he used. Appreciate the comment

 

[John Leinemann]

Unrelated to your question, but there is a guy local to me who turns bowls just like the one in your pic: BoardstoBowls. We mostly sell our wares in different venues so I've only met him once and didn't ask, but if you look at the link you will see numerous variations on that straight, outward-flared wall design with that plug in the flat bottom. Not really my taste, as I am all about chasing that elusive perfect curve; I am just curious about the technique. Is it started from the bottom on a screw chuck and then the hole is plugged?

I don't get it. When I use a screw chuck as I usually do with platters, I screw it onto the top of the blank, finish the bottom, then chuck it into the recess to turn out all evidence of the hole, but different strokes for different folks, I guess. Anybody want to weigh in on this technique?

I remember getting some cloudy stuff like that when I tried to wipe on oil in very humid conditions, so residual moisture could definitely be the culprit.

edit to add: I've turned my share of padauk (even though I hate its noxious orange dust!), and I've never had an issue with it taking a TruOil finish (which is basically a wiping varnish). I'm pretty sure it's not the wood.

Hi Aaron. The system for making bowls like this is called a Ring Master. It’s an interesting set up. It’s not a lathe.

View: https://m.youtube.com/watch?v=4MzIq4e3No4&pp=ygUXcmluZ21hc3RlciB3b29kIHR1cm5pbmc%3D

 

[Bill Blasic]

I have a Ring Master for my lathe (16"). They are supposed the have a hole in the bottom piece (as that is how it is held), But thanks to my good friend Jim Danbury my Ring Master bowls no longer have a hole in the bottom that has to be plugged. Jim used a 1 3/8" expanding collet chuck from Penn State Industries. It came with a 1 3/8" Forstner bit. You drill a 1 3/8" hole about a 1/4" deep and expand the collet into it. It has worked flawlessly for me. The bad part is that Penn State Industries no longer sells these (as I would love a backup).

 

[James McCall]

I've had that issue with padauk. Nothing else.

I applied linseed oil and wax to it. It seems like the wax almost precipitates back out? Is padauk oily?

 

[John Leinemann]

I have a Ring Master for my lathe (16"). They are supposed the have a hole in the bottom piece (as that is how it is held), But thanks to my good friend Jim Danbury my Ring Master bowls no longer have a hole in the bottom that has to be plugged. Jim used a 1 3/8" expanding collet chuck from Penn State Industries. It came with a 1 3/8" Forstner bit. You drill a 1 3/8" hole about a 1/4" deep and expand the collet into it. It has worked flawlessly for me. The bad part is that Penn State Industries no longer sells these (as I would love a backup).

Thank you, I will pass this on the my Club mate.

 

[John Leinemann]

I've had that issue with padauk. Nothing else.

I applied linseed oil and wax to it. It seems like the wax almost precipitates back out? Is padauk oily?

I personally don’t know… I haven’t worked with Padauk yet. Anyone else know more about this species

 

[Gerald Lawrence]

I have two planks of Padauk in my shop . One is what we would call normal but the other has that white film. You can wipe it off but it does come back. This is unfinished wood. So from this I would say it has nothing to do with finish but is simply oxidation.

 

[Bill Alston]

From what I’ve read you can sometimes get something that looks similar to this if the finish is applied in a damp environment.

 

[Walker Westbrook]

I have two planks of Padauk in my shop . One is what we would call normal but the other has that white film. You can wipe it off but it does come back. This is unfinished wood. So from this I would say it has nothing to do with finish but is simply oxidation.

I have been having a similar issue with a small padauk turning I made. I haven't applied any finish yet, but it's getting a white haze. It wipes off easily, and like you said always seems to return. I was hoping that finish would resolve the issue. Sounds like from other responses, the finish would not be the solution.

 

[Pat Wisniewski]

Carnauba wax finish on a Padauk piece keeps getting that white film… wipes away easily enough, but comes back. I was looking for info on this and in a Fine Woodworking forum thread I saw this (see photo).
I’ll have to try wiping it down with denatured alcohol.

 

[John K Jordan]

I personally don’t know… I haven’t worked with Padauk yet. Anyone else know more about this species

I've turned Padauk. I'm not a big fan. The color is nice at first.

The Wood Database website lists it as one of the Top Ten Overrated Woods:

Top Ten Most Overrated Woods | The Wood Database

www.wood-database.com

Here's their entry for African Padauk:

African Padauk | The Wood Database (Hardwood)

www.wood-database.com

However, I disagree with a few of those in Eric's list. Specifically, wood from different trees can vary widely. And much may, as usual, depend on what you turn and how it's finished. For example:

• I have some Purpleheart that simply refuses to turn brown. A friend from South America is amazed at the popularity of Purpleheart in the US. He said they use it for things like floor joists.
• I find Bloodwood a joy to turn, especially small things - fine grain, good surface off the tool, great for finials and such. Some has stayed wonderfully red for a decade. Maybe it's the specific wood, maybe the finish. I have some big pieces but I cut them up into small pieces.
• Polished black ebony is indeed nearly indistinguishable from black plastic. However, I look for pieces with brown streaks. Also, making it slightly "unpolished" with 0000 steel wool is better, IMO.
• I like the look of Ambrosia Maple.

JKJ

 

[Aaron Harris]

Weird-I've never had this issue on padauk. I wonder why? And John-I thought everyone likes ambrosia maple. I try to keep a few pieces turned from it on my craft show table; it usually sells before anything else. I guess Eric is entitled to his wrong opinion.