Dilemma on which method to use to apply final lacquer application

[Don Morris]

I have some African Rosewood from which I'm making a headboard. I don't have an HVLP system in my small shop, don't have the resources or space to add a quality one either. Right now my plan is to place a couple coats of Shellac followed by Behlen's Vinyl Sealer (aerosol spray can) and finish with something like Deft aerosol spray can lacquer. I've seen several presentations by woodworkers using Behlen's Musical Instrument lacquer, that were impressive. But this was definitely an HVLP spray only formula. That's why I was figuring to go with the Deft aerosol can spray lacquer. The aerosol can presenters seem to acknowledge a little more difficulty in achieving a great result compared to using an HVLP system and the lacquers that can be used in such a system. However, I also came upon a demonstration of an inexpensive HVLP Harbor Freight gun (with regulator and spray adjustment) that wouldn't "break the bank". I wouldn't mind spending $$$ on an inexpensive HVLP system if I knew I would most likely get a significantly much better result. At no time am I going to be spraying heavy paint, just clear lacquer. Opinions please! Would it be worth it to get an inexpensive system so I can "spray" a quality lacquer? Or can you also get a great finish from the Deft aerosol system? Many Thanks for your input! Don M.

[Jim Becker]

Relative to the type of product you speak about, you don't need a million dollar gun to spray it acceptably. A $130 gun with the correct needle set and a compressor with enough air flow to meet the gun's requirements will do a good job.

That said, please remember that spraying solvent-based lacquer can be dangerous in a home shop situation where you don't have a proper spray booth, etc. If you're spraying outside, no big deal, but indoors? It can be nasty stuff. And it's explosive. I only mention this because I can't not mention something related to safety...it's in my nature. I personally only spray water borne products and sometimes shellac if it's warm enough to properly ventilate the shop by opening things up.

[Don Morris]

Safety First is often said here first too. I intend to do this in the garage with the door open with my 3M mask and filter changed from particulate matter to an organic vapor filter. I'm already overbudget on this project so my financial situation is such that I could perhaps justify the $29.00 at Harbor Freight. Along with a 20% coupon, that's almost pocket change, and it shouldn't be a problem. $130.00 would be much harder to justify. I went back to my "Flexner bible" and re-read again. Perhaps a final application of Deft Clear Wood Finish might be an answer to my needs. Flexner even shows a photo of him brushing a raised panel with Deft Clear Wood Finish. That's what I will be doing in the design of my headboard. I will have to switch from the Behlen's Vinyl Sealer to Deft Lacquer Sanding Sealer before the Deft Clear Wood Finish. The bad thing is I won't be able to justify getting another tool (spray gun). One of the reasons I went overbudget was i bought a portable spindle sander to better do some curve sanding. That raised the eyebrows of LOML, who does all the family financials (bookkeeping/financial background). Definitely got the impression I needed to stop there.

[Willem Martins]

I spray everything I make, except pens with fast drying finishes in my shop. No booth, just good ventilation, a mask with carbon filter and using HVLP. By the time the finish reaches the floor it is dust. I use disposable cups and it takes a few minutes to clean my gun, actually faster than cleaning a paint brush.

Personally I would avoid inexpensive equipment, which will end up impacting the quality of your work and cost more in time. No matter how nice your work is, the finish could either make it, or spoil it. There is always the alternative to find the closest cabinet shop and ask them for a price to spray and finish in their professional spray room. Even with good quality spray equipment and a big compressor, there is a learning curve towards laying down a professional finish.

Spraying a head-board with rattle can is an adventure I would avoid.

[Don Morris]

In my small basement shop there is no option to install "good" ventilation for anything beyond low to moderately volatile fumes. I installed a ceiling ventilation system, and have 4" flexible ducts (or whatever size is standard with the unit) running from just about all my machinery to an 1100 cfm standing unit. There are no windows and the shop is walled off from the rest of the basement. With a large fan at the entrance to the shop, I would rate my ventilation capability as fair to poor. About 30 years ago my son and I took a VW super bug from a junk yard and restored it. We bought all the things necessary to spray lacquer, and did that in my garage, which we walled off with fans, sheets of plastic, etc. I bought a top-of-line DeVilbiss gun and we shot the car with BMW red lacquer. Looked great. Sold all but the compressor, which I now use for air driven woodworking tools. I was told that Devilbiss gun style isn't legal anymore. So I'm somewhat familiar with spraying lacquer. Just not a good idea in my shop because of the poor ventilation for such tasks. Up to now, I've gotten by with the likes of Arm R Seal Oil and Urethane topcoat for most of my needs. But that's just not recommended for the particular wood in my present project. Thus...I'm now leaning to finishing the headboard in my garage (door open on a nice day) with Deft Lacquer Sanding Sealer followed by Deft Clear Wood Finish. But, after reading and reading and reading...I'm envious of you guys with the capability to spray. Most everyone who does, says that's the way to go.

[John TenEyck]

I don't understand why you ruled out using Arm-R-Seal or some other wiping varnish for this project. Seems to me that would have been a good choice given your circumstances. Finish the panels if any separately, then finish the frame after assembly.

John

[Steve Schoene]

Oil based varnishes or oil/varnish mixes are often problematic to use on rosewood which generally falls within the "oily woods" category. A couple of shellac coats would make it possible to use an oil based varnish. BUT remember, most polyurethane varnishes can have adhesion problems over shellac, though dewaxed shellac usually facilitates adhesion. But, I'd still recommend a non-polyurethane finish for an extra margin for adhesion AND tends to look better it terms of greater clarity. A oil-based varnish does give greater durability and protection than single part lacquers.

Also with a tricky wood like rosewood, I strongly recommend test samples from end to end to make sure the finishing schedule you want to use actually works out as you plan.

[Don Morris]

African Rosewood has a rather open pore system and lots of internal resin. The following is a quote from the Hobbithouseinc.

" I have definitely experienced (and seen extensive anecdotal comments to the effect) that gluing is best done very shortly after machining/sanding operations, NOT after the wood has sat around for a few days. Also, many woodworkers highly recommend acetone to remove the surface oil before gluing. Personally, I have found this to be sometimes ineffectual, at least with cocobolo. I once had a piece that gave me a great deal of grief in finishing, so I completely stripped and re-sanded it and immediately rubbed it down quite vigorously with acetone, then waited a few minutes and again rubbed it with acetone, and then did that one more time. Each time, the rag I was using came away quite red, although noticeably less so on the 3rd application. I then applied polyurethane, and a month later it was STILL not dry."

Thus I'm heavily leaning towards a lacquer.

[Mike Wilkins]

I have used the Harbor Freight HVLP gun powered by a 2-tank Emglo compressor like the ones the contractors use to power their nail guns. I have sprayed polyurethane, lacquer and shellac with no problem. I usually thin the poly 50/50 or 75/25 and get good results. I have to spray outside on a non-windy day. You can get by with a small compressor using that gun.

[John TenEyck]

I didn't know rosewood was one of the "problem" woods when it comes to gluing/finishing it. But shellac sticks to darned near anything, including Teflon, so I have to believe it will stick to Rosewood. And anything sticks to dewaxed shellac, so I'd have no qualms about applying Arm-R-Seal over it, or Waterlox, or some other wiping varnish for that matter. Of course I'd make samples first and do an adhesion test to prove to myself it all works.

FWIW, I've never had adhesion problems of Arm-R-Seal over dewaxed shellac, nor with the WB polys I often use either. On the outside on the can of SealCoat shellac it says something like "compatible under all finishes".

John

[Don Morris]

That's a thought, I certainly was planning on putting a couple "wash" coats of shellac on first. Maybe I should re-think my plan and instead of a 1/2 lb cut up it to a 1 lb cut or even a 2 lb cut then put Arm-R-Seal over that. That would simplify things greatly. A test board is certainly indicated. Waterlox isn't allowed in the house by LOML after it was tried several years ago. The odor nearly drove us out of the house for several days even though I had two fans directing the fumes out the garage door. I don't go there.

[John TenEyck]

SealCoat comes as a 2# cut. When I use it as a sealer, I use it straight from the can w/o cutting it further.

John

[Don Morris]

Still haven't heard from anyone who has used the Deft Aerosol can system vice an HVLP approach. How close to an HVLP result can you get?

[Jim Becker]

Spray bomb cans are relatively effective on small components/projects, but are harder to use for larger panels, etc., because of the spray fan width being very narrow at the optimum distance from the workpiece. It's a challenge to get even coverage in that case. Using an HPLV gun will permit a wider fan at the optimum distance with less work to get an even coat without overlap marks.

[Don Morris]

Thanks for the input Jim. Your comments always are appreciated. BTW your design of outfeed table has been working well for a bunch of years and soooo much better than the poor excuse for the one I had made up for myself before.

I'm going to get the cheap HF spray gun, use a lacquer finish, and do the job outside or in my garage on a nice day. It isn't that big of a task. One real good brushing lacquer brush would set me back perhaps as much as or more than the HF gun. I have read that a good brush can make a big positive difference. I still have the organic vapor filters for my 3M mask I bought for trying Waterlox. Thus the outlay of funds will be minimal and at least the finish time will be faster than the Arm-R-Seal Urethane desk top I'm making for LOML at present.

Thanks to everyone for taking their time to respond. Creekers Rock! And I donate.

Don M