Let us start with the simple question: can you spray the finishes available at Earth and Flax?
Most of the traditional natural, oil-based finishes are not practical to spray but Linseed Oil Paint is technically the exception.
That said, we do not recommend it.
Why?
Primarily because it is not the big time saver the folks may think nor is it very economical.
If you spray Linseed Oil Paint, you would still need to back-brush to ensure a thin, even coat.
This is imperative to achieve an ideal dry time and the most attractive finish.
If too much Linseed Oil Paint is applied, it will take a long time to dry and can wrinkle or orange peel as the top layer dries at a different rate than the underside.
Another big downside is that a significant percentage of product is lost as soon as it becomes airborne. This is quite wasteful and you can expect to not get the projected coverage with this application method.
Not only that, paint may settle on surfaces in the vicinity, including roof, garden, parked cars, etc. Spray with care and with an awareness of your surroundings.
Finally, cleaning the sprayer and lines will not be super easy. Linseed Oil Soap is generally your easy clean-up method but solvents may be required to clean sprayer and accessories. Very unfortunate as the Linseed Oil Paint system can be 100% solvent-free otherwise.
Clean-up and back-brushing means spraying is really not faster or a big time saver.
A more effective alternative to spraying would be to apply carefully with a small nap roller, careful to avoid overloading and causing excessive drips/waste.
Roll on and then back-brush to ensure thin, even coats. Back-brushing will be necessary.
The roller method can also be used for the other finishes that should not be sprayed like the Authentic Pine Tar. Authentic Pine Tar is too resinous to spray and will likely clog the equipment quickly.
In summary, downsides of spraying:
Difficult to apply thin, even coats. Must back-brush.
Less coverage and more waste.
Excessive clean-up.
If you want to try spraying Linseed Oil Paint, manufacturer's recommend a high pressure, small nozzle sprayer.
We would recommend you do a test first to confirm strategy and technique before attempting a larger project.
Again, this is not a recommended application method and is only an option for Linseed Oil Paint.
If you are interested in finishes for cabinetry or furniture, take a look at our Painting Kitchen Cabinets with Linseed Oil Paint article.
Note:
Spraying finishes became increasing popular across industries in the 20th century but primarily focused on automotive and other commercial applications, including mass-produced furniture and cabinetry.
It is not until relatively recently that exterior siding or interior walls of residential structures are being sprayed. Partly this is because the tools necessary to spray have become more affordable to professionals in the field but also because lower-cost, water-based petrochemical formulations (plastic paints like an acrylic/latex) are easier to spray than petrochemical oil-based paints or natural oil-based paints.
The industry focus on cheaper materials and cheaper, faster processes is evident and going strong but the results are often far from exceptional so there is a return to craft (primarily motivated by the homeowner) in many respects, including timber frame construction, lime plaster/tadelakt wall treatments, and hand painted finishes using non-petrochemical based formulations.
At Earth and Flax, we would argue the extra labor and time required for traditional coatings is well worth it based on the exceptional, healthy, long-lasting results achieved.
It is certainly costly to hire someone to do this level of work so learn application technique and do it yourself! Instructional and inspirational content available on the Earth+Flax YouTube Channel.