Spraying a wipe-on finish ?

[wojo2]

I have been working on a blanket chest for several months now, and am almost done with the build part of it. The design is a rail and stile type construction, with floating panels. The wood is bubinga for the rail and stiles, and soft maple for the panels. I want to keep the finish as natural as possible, so I am planning to use General Finish's Seal-a-Cell, followed with Arm-R-Seal. I realize that both of these are "wipe-on". Given the size of the chest, I was considering spraying the finish instead of wiping it on. Is there any reason why I should wipe these on instead spraying? Any advise or suggestions greatly welcome.

Earl

[PurpLev]

From what I've seen:

"brush on" Poly = Poly

"wipe-on" Poly = thinned Poly

"Spray-on" Poly = Thinner Poly

See where this is going? it's all the same poly, at difference viscosities. as long as you thin it to the right viscosity I think you should be fine.

I would be curious to hear if anyone can prove this wrong though.

[PaulMarcel]

Like Purp, I haven't sprayed either, but like Purp, I agree you should just have to adjust the viscosity with solvent. Even if you can get a big enough needle/nozzle pair to pass the varnish, I think you should go with a smaller nozzle and more solvent so it lays up nicely.

As for the Seal-A-Cell + Bubinga... you're gonna love that. If you want to spray the Arm-R-Seal, go ahead, but I think wiping the Seal-A-Cell will accomplish much more.

Usually I think SAC (ha ha, "sac"..) 75% Mineral Spirits to 24.9% SAC (the other 0.1% is an inevitable bug that flies into it).

Put that on heavy with a rag; you want to see a thick glistening layer.

I usually do a large part then go back for the wipe down.

When your rag is pretty much dry, use it to wipe down the excess (not a separate dry rag that will suck up some SAC).

Now, here in Arizona, it doesn't take long, but wait until that first coat is in and the top surface looks dry. For me, that's 1-3 hours. Apply coat 2. Repeat for coat 3. Coat 3 for me is the ahhh-factor when the chatoyance really starts with the light. Leave that to dry overnight till it 'dusts' with sandpaper before applying Arm-R-Seal.

The idea is to use the highly thinned SAC so it soaks deep into the wood then follow up with the other coats before previous coats fully seal the wood preventing more SAC from getting in there. I think the reason the chatoyance is so much nicer is because of a prism effect much deeper in the wood.

Regardless the why, I now always do that with SAC before Arm-R-Seal. Try it on an offcut of the bubinga to see if you like it. Spraying SAC in this case wouldn't work as well (I think) since the idea is flood and wipe and is part of the reason it works.

[Sac]

Hey Paul, whats so funny about "Sac"? Something wrong with that?

[BillN]

I just finished up a big QSWO dining room table and sprayed on the Arm-R-Seal oil & urethane after dyeing with medium brown Transtint and filling the pores. The finish came out terrific. I did not thin it more than it was thinned out of the can. I used a cheap HVLP unit from Rockler. It did take a few coats to obtain the 3D effect from the dye, but the best part was no lap marks. My surface was horizontal. You do have to be careful about vertical surfaces to avoid the thinned finish running or sagging. It's a good idea to watch some of the Youtube vids on spraying technique to avoid some of the beginner errors.

[thewoodwhisperer]

One of these days i have to revisit spraying oil based finishes. I never had much luck with it so now I completely avoid it. But both arm-r-seal and seal-a-cell spray well, and a little naptha or mineral spirits is all you need to tinker with the viscosity. Actually, I think you could probably just spray these wiping formulas right out of the can. But I agree with Paul in that you'll get more "depth" to your finish if you wipe it into the grain with some initial light coats. For speed, you could simply spray and wipe back.

Now here's where my opinion differs a bit. I generally only use Arm-R-Seal these days. I found there to be absolutely no visual difference between a board with 5 coats of arm-r-seal and one with 2 coats of Seal-a-Cell followed by 3 coats of Arm-R-Seal. I consider these redundant products. I have actually done a few tests on some maple boards where I could really spot color variations, and I couldn't see a difference. Generally speaking, Arm-R-Seal is the more durable topcoat, so I just stock up on Arm-R-Seal and call it done. Just my opinion from my observations.

[AceHoleInOne]

Generally speaking, Arm-R-Seal is the more durable topcoat, so I just stock up on Arm-R-Seal and call it done. Just my opinion from my observations.

Marc is the Arm-R-Seal product you used the gloss, satin or semi-gloss or does it matter?

-Ace-

[thewoodwhisperer]

I actually stock up on all three sheens: gloss, semi-gloss, and satin. But keep more gloss around than anything else. Most times I'll build up using gloss and finish off the last 2 coats with my sheen of choice, be it semi or satin. Just depends on the look I'm going for and the species I'm working with.

[PurpLev]

FYI: I actually DID spray. but I'm sticking with waterborne spray finishes because I finish in the basement, and only have a window fan to vent the space so I wanted the least harmful stuff in the air - also something that won't start a fire for all oil based finishes I stick with brushing and wiping (brush first 2 coats to build up the film, then wipe-on another ~3 coats to even it out and quicken the process)

[AceHoleInOne]

I actually stock up on all three sheens: gloss, semi-gloss, and satin. But keep more gloss around than anything else. Most times I'll build up using gloss and finish off the last 2 coats with my sheen of choice, be it semi or satin. Just depends on the look I'm going for and the species I'm working with.

As Seal-A-Cell being only a clear (as the can stipulates) oil, (no flattners) I suspected, you would start off with the Arm-R-Seal gloss, (if you omit the Seal-A-Cell), then adjust your sheen with the satin or semi-gloss. Cool, thought I'd ask, just to be sure.

-Ace-

[Sac]

I actually stock up on all three sheens: gloss, semi-gloss, and satin. But keep more gloss around than anything else. Most times I'll build up using gloss and finish off the last 2 coats with my sheen of choice, be it semi or satin. Just depends on the look I'm going for and the species I'm working with.

Why would you build up with gloss? Is it just thicker or harder?

[PaulMarcel]

The flattening agents will build at the same time as you build your finish. By the time you build your finish sufficiently, you will likely have too many flatteners making a muddy finish. After you build most of the finish with gloss (which is to say, finish with no flatteners), you add a couple more coats until the flatteners leave you with the sheen you want.

Maybe a better way to illustrate. Say you wear pink tinted glasses (and we know you do). Say to create a finish, you need 5 lenses worth of glasses at least for a satisfactory build (and fashion statement).

If you piled 5 pink lenses on top of each other, the pink would be so overwhelming that you couldn't see anything through them or at least without crisp detail.

Instead, if you piled 3 clear lenses then 2 pink lenses, you'd have sufficient build and enough pink without being too Paris Hilton to see crisp detail with just the pink hue.

Make sense?

Here's another crazy idea that was an experiment that worked for me.

For an outdoor cabinet, I wanted 7 coats to protect it. I put 3 gloss then 2 satin then 2 gloss. The topmost gloss layers really don't add gloss; you see through them to see the flatteners in the satin layer. Why I did it that way is for renewing it. Now, every couple years, I can give a light scuff sanding to remove dirt, roughness, bird *$^&. That will take off some damaged and flaked varnish likely from the top two layers. I can put down refreshing coats of gloss again and not affect the sheen as that was set by lower untouched layers. Allows for spot fixes (parts that get way more sun) without having those parts come out with a visible sheen line.

[AceHoleInOne]

Keep in mind flatting agents serve another purpose other than desired sheen.

Gloss finishes that are not polished are less slippery than satin’s. A satin or semi-gloss finish that has flatting agents in them has slip. The flattening agents will cause the dust and dirt to not scratch the surface and you don’t want stuff to stick to the surface for easy cleaning. That is typically why a satin finish is predominately used in furniture making.

-Ace-

[Sac]

Paul, that is what I was thinking, I just wasnt sure if there was some other reason. Thanks for the clarification..