Has anyone used Briwax on Venetian Plaster? If so whats the best way to apply this without getting the spotty look. Thank you again everyone.

What plaster are you using?

Aldo, it is true tha the type of plaster you are using can cause it to be somewhat porous and thus blotchy.

A few things to keep in mind when playing with Venetian plasters:


1. VPs, altho almost universally resin based, (grasellos are called lime VPs in come circles), do not have the same type of resin, the formulations are different.

2. The fillers used are also different for each type. For instance, I might take VP from company 1 and it is very plasticky feeling, smeling and looking, another might be very amoniated smelling, yet even another might not have sheer characteristics and are more like applying clay to a wall.

3. Each one of the above variations will have a different porosity. Yes, some VPs are more porous than others .

4. If you run your jap knife or blade over the VP while applying the last coat and start to shine it up a little, (aka.. burnish it), it tends to not accept glaze or staining or oxide washes as readily in those areas, however, if in your application technique, you leave a textured feel, (even if you can't feel it under your hand all the time, but if in your technique you are not filling in from wet to dry, you will inevitably get some highs and lows. IT is THIS affect that will cause any burnish to only hit the highs. Thus, when you go back and add any colored waz, it is going to suck up a little faster in the lows.

5. Lastly, if you go back and sand lightly, say with 600 grit, you open up the surface, even tho you tend to noralize all of it, it is more apt and ready to accept a wax and grab, (rather than slide). This could create blotchiness also....

Kolcaustico, for instance, is a very plastic feeling VP, they use liberon wax, which is similar to Briwax and it seems fine...

6. LAstly, the wax itself can be an issue. ALL those type of waxes, whether liberon, briwax or even the black bison wax many use in this forum are all SOLVENT based. This means when the solvent and al the smelly stuff dissipates, what you have left behind is "wax". Most of them smell like shoe polish becasue in effect, they are just "glorified vesions of shoe polish" and nothing more.
Now, why are they so high in solvents? Because solvent cuts thru old wax buildup, it cleans and all those products were created , by the manufacturer to be used on OLD FURNITURE and the characteristic of being able to clean and wax in one step was highly favored and sought after! BUT, it can create issue for us. When we apply any type of wax such as these, sometimes, while in application, we can "spot" the plaster becasue it is porous, a drop or something or a swirl mark will remain if we are not gentle and apply evenly, lightly and randomly... The reason is the solvent immediately sucks into the finish and carries with it, any coloring which you call spotting. and the reason is the surface is not uniformly porous, (due to partial burinishing in places, due to more product in some places vs others, due to sanding or whatever)....

The issue is not always VP, the issue in reality is the wax itself. We, in the industry, by using a wax not made for VP applications have to overcome the issue of the wax and it's penetration by overcompensating whether by technique or by using a very plasticky feeling" resin based VP that creates uniformity of the surface....

Remember, in the end, what your goal is, is to apply a wax to a surface for the purposes of polishing it and getting a "waxed shine" and secondarily, for some protection which wax offers. That wax requires a vehicle, or a base from which it is transported. Historically, that base has been solvents. Sometimes, they would melt the wax and apply it but usually, it is wax in a solvent. AS of recent, some modern plaster comapnies have been able to create water based vehicle for the wax, in part, it is a modified wax with some acrylic which retains all the qualities of the wax but allows you to apply it in a water based solution.... These new waxes are also being used in lime based applications allowing the lime to remain breatheable.

My suggestion is to go back to the VP manufactuerer who made the VP, go to their website, call their sales department, I have even talked to their chemists in the past becasue typically a troubleshooting issue a sales person cannot answer is usually followed up by a chemist as I have experienced a few times in the past. But if you have any experience at all using VP, then all I ahve said above is just replay. you know some absorb differently, yo uknow aht burnishing wil do, I am assuming you are not totally a DIYer since you would not have brought up briwax from the beginning.


The answer is to "know your VP and all it's characteristics first, know how the wax works and then adjust your technique for that particular VP. The trick to learning to be an artisan is to experiment, to undestgand the underlying characteristics of all the products you use and why they behave in the manner they do. ageneral statement, why does my VP do this assuming all VPs act in the same way and they do not.

hope that semi-dissertation helped.

Thank you Carmine that was very imformative I look forward in picking your brain more in the future. Doyle the VP is the Behr stuff. Thank you again.
P.S. I tried using sanding sealer today and it works great no spots when applying the wax.

Hi Aldo, I am very very new to this site. But I could not help noticing your topic. I have used solvent waxes and acrylic waxes and Italian soaps over the product brand you mention. And a host of varnishes. I will search this site to see if I can find some of your work posted.

Aldo,

I have applied Bri-Wax over VP...it was by Texston. It was applied with cheesecloth, rubbing in a circular motion.

I stay away from Bri wax. I used black bri wax to "patina' a finish and it removed the finish from the sample board.

Carmine, thanks for all the info on the waxing issues. My question is this...why havent alot of these companies come out with waxes made specifically for VP's??? I know Safra has the soap based Mil. Wax which is really nice for what it is, but I have discontinued using Liberon as it is too toxic for me to tolerate.

Thanks,
Greg