A series of questions about water-soluble aniline dyes

[mrFinpgh]

I will of course test everything prior to committing it to a piece, but had a couple questions running through my head.  I'm sure some of you on here have thought these things through already.

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[*]Is Osmo PolyX compatible with water-soluble dye?
[*]If compatible, is Osmo sufficient to 'seal' the dye in enough so that it does not come off if the piece were to get wet? 
[*] In general, it sounds like dyes are to be avoided on food contact items.  I assume because the dyes themselves don't really 'cure' and can be reactivated in contact w/ the solvents.  Is there a caveat to this?  For example - does sealing a piece with varnish mitigate this concern? 
[*] What about something like a serving tray?  Would the above continue to be a reason to avoid using dye?  Or does the issue become moot?  I'm imagining that someone might take a serving tray and decide to present cheese or fruit on it, which could wick some moisture..  how much finish would be needed to consider using a dye to be safe?
[/list]

 

[mrFinpgh]

Just an update on this.. hopefully someone else will chime in with some thoughts/experience.

I did a little sample piece this week using a drop from some flame birch I'm milling up.

What I did:

Sanded to 150
Raised the grain with a very dilute coat of WD Lockwood Honduras Brown Mahogany dye - basically the 'trace coat' approach
Sanded the bulk of this off at 150
Applied a strong coat of WD Lockwood Golden Yellow dye
Applied the first coat of Osmo with a red pad (I cut off pieces from a leftover buffer pad), finishing by wiping off with a white pad and then buffing with a blue shop towel
waited about 12h
Did a light scuff with some 600g paper
Applied a second coat of Osmo with a white pad, buffed off with a blue shop towel.. Let dry overnight
Applied a third coat of Osmo with a white pad, letting the Osmo sit on the surface for about 10m before wiping with a white pad and then removing any excess with a shop towel.

Result so far:

View attachment 1

Observations:

• The first coat had a lot of liftoff from the dye.  I had to buff quite a lot before the towel didn't come up yellow
• The second coat still had some, but less liftoff.  By the time I buffed it it was relatively little dye transfer to the towel
• I usually don't sit around letting the Osmo dwell on the surface.  Typically I apply it more thinly (just enough to look wet.. nothing really sits on top).  I decided to let it sit a little this time because I thought perhaps it would offer slightly more of a build (microns, I'm sure).
• The last buffing didn't really show any appreciable dye transfer
• I really like the appearance of the Osmo over the golden yellow dye..  I think perhaps sanding to 240 might have looked even better with the flame birch figure. In general, I suspect higher grits are probably a good idea w/ flame figure just to get the endgrain of the wood to be a little less blotchy.  I don't think I would do it on wood that wasn't prone to blotching.

I am trying to make a call as to whether I could use Osmo over dye for some serving trays or even an entryway bench.  In both cases, my concern is primarily that there is some potential for transfer to skin/clothing/food items.  I could use something like arm r seal or a waterborne lacquer over a coat of shellac, and I think in those cases the risk of transfer drops but the finishing process becomes a bit more complicated - particularly now that it is getting colder.  I'm leery of spraying WB lacquer when the outside temperature is cool, since I would need to have the door open near where I'm spraying. 

 

 

[tjbnwi]

I’d cover the oil finish with a clear waterborne finish after a week or two of cure.

Tom

 

[mrFinpgh]

Hey [member=4105]tjbnwi[/member] ,

Thanks for your feedback.  I didn't think you could really go over a hardwax oil with a film finish.. is that even possible?

Do you think I could get away with spraying a waterborne lacquer despite the lower temperatures?  I usually spray near the door out of my basement (blowing out overspray w/ a fan+ filter) and then move parts away from the door.  I've only read about how sensitive waterbornes are to temperature, so I wouldn't want to have issues with the finish coalescing. 

 

[tjbnwi]

[member=59039]mrFinpgh[/member],

I’ll get back to you tonight.

Tom

 

[tiralie]

I am trying to make a call as to whether I could use Osmo over dye for some serving trays or even an entryway bench.  In both cases, my concern is primarily that there is some potential for transfer to skin/clothing/food items.  I could use something like arm r seal or a waterborne lacquer over a coat of shellac, and I think in those cases the risk of transfer drops but the finishing process becomes a bit more complicated - particularly now that it is getting colder.  I'm leery of spraying WB lacquer when the outside temperature is cool, since I would need to have the door open near where I'm spraying. 

If you can get some Rubio 2C, it will not transfer. It is a 2 part oil finish that can be applied like the Osmo. The Osmo poly is tougher.

 

[tjbnwi]

[member=59039]mrFinpgh[/member],

I have not had an issue with KA+ bonding to oils if I let them cure completely, about 14 days. I gently scuff the oil, apply topcoats.

Tom

 

[mrFinpgh]

If you can get some Rubio 2C, it will not transfer. It is a 2 part oil finish that can be applied like the Osmo. The Osmo poly is tougher.

Hi Tim,

Are you saying get the Rubio oils w/ the colors?  Or Rubio over the dye?

I did a couple krenov style sawhorses this summer w/ the 2C in blue and green.  It's fun stuff -  and my favorite smelling finish - but those colors seem to be mostly pigment - they obscure some of the grain.

If you meant Rubio over dye - why would it do a better job preventing transfer as opposed to the osmo?

Also curious about the assertion that Osmo polyx is tougher than Rubio 2c.  I've never needed to test that hypothesis and I'm wondering whether there is some data out there or if this is derived from experiences.

Thanks,
Adam

 

[mrFinpgh]

[member=59039]mrFinpgh[/member],

I have not had an issue with KA+ bonding to oils if I let them cure completely, about 14 days. I gently scuff the oil, apply topcoats.

Tom

Hi Tom,

To clarify - hardwax oils?  Not just danish oil or boiled linseed or tung oil?  I guess I'm having a hard time imagining the WB product bonding to a surface where a big part of the recipe is wax..

 

[tjbnwi]

[member=59039]mrFinpgh[/member],

I have not had an issue with KA+ bonding to oils if I let them cure completely, about 14 days. I gently scuff the oil, apply topcoats.

Tom

Hi Tom,

To clarify - hardwax oils?  Not just danish oil or boiled linseed or tung oil?  I guess I'm having a hard time imagining the WB product bonding to a surface where a big part of the recipe is wax..

I don’t recall ever using a wax finish then coating it.

In the wax case, I’d probably wax over with Bri-wax, then buff.

Tom

 

[tiralie]

Are you saying get the Rubio oils w/ the colors?  Or Rubio over the dye?

I mean the Rubio Clear 2C over the dye. You may lift some of the dye with the application as it is slightly abrasive if you use a white 3M scotch bright pad (which I like over every other I have used) to apply it.

I did a couple krenov style sawhorses this summer w/ the 2C in blue and green.  It's fun stuff -  and my favorite smelling finish - but those colors seem to be mostly pigment - they obscure some of the grain.

The clear has a classic warm solvent colour but it is clear when dry. Looks fantastic with Walnut.

If you meant Rubio over dye - why would it do a better job preventing transfer as opposed to the osmo?

The 2C is a two part with a hardener which seals better than a traditional oil without a hardener.

Also curious about the assertion that Osmo polyx is tougher than Rubio 2c.  I've never needed to test that hypothesis and I'm wondering whether there is some data out there or if this is derived from experiences.

I have used Rubio 2C and Osmo PolyX on a maple kitchen island counter top (same situation/location etc.) and the Polyx performed better. The Rubio 2C tended to stain, get marked up and absorb more food color from spilled food etc. The Rubio is good if it's not in a kitchen where there is a lot of moisture or food spills etc. I have used Rubio in retail applications, but that application was for a men's clothing store and basically it was for displaying and resting expensive clothing on it.

I have found that the toughest (water bourne) finish ultimately is a two part polyurethane, but you need to spray those.
Tim

 

[mrFinpgh]

I mean the Rubio Clear 2C over the dye. You may lift some of the dye with the application as it is slightly abrasive if you use a white 3M scotch bright pad (which I like over every other I have used) to apply it.

The clear has a classic warm solvent colour but it is clear when dry. Looks fantastic with Walnut.

The 2C is a two part with a hardener which seals better than a traditional oil without a hardener.

I have used Rubio 2C and Osmo PolyX on a maple kitchen island counter top (same situation/location etc.) and the Polyx performed better. The Rubio 2C tended to stain, get marked up and absorb more food color from spilled food etc. The Rubio is good if it's not in a kitchen where there is a lot of moisture or food spills etc. I have used Rubio in retail applications, but that application was for a men's clothing store and basically it was for displaying and resting expensive clothing on it.

I have found that the toughest (water bourne) finish ultimately is a two part polyurethane, but you need to spray those.
Tim

I do have a 4 stage turbine setup, but with the weather getting cooler, I'm leery of spraying as I would have to keep my basement door open to blow out the overspray.. while I've gotten good results spraying, I don't think I have the experience to be confident that I could get away w/ spraying  + then moving items away from the door.

I did my floors w/ Rubio 2c when I moved in..  they have held up well over the past 5 years although the Kitchen probably could benefit from a refresh in a few spots.  As you said, it does seem to take up stains from coffee/oil/vinegar.  For a serving tray, it doesn't seem like it would necessarily do the best.

I used Osmo Top Oil on my walnut countertops and those are coming up on three years. They have mostly done well but I have noticed some scratching and the area around the sink has some raised grain at this point. Again, due for a touchup probably