Polyurethane before or after bed assembly?

[Stephen McCreery 2]

We needed a bunk/trundle bed. I couldnt find any plans online for one so i just made my own. Anyway we are done staining and i am ready for poly. Should i do this before or after assembly?

It is a 1x design with 4's and 6's (and a 12 for the trundle). The rails bolt on with carriage bolts. I just want what is best. No need to cut corners. I did stain in pieces. (Rails, end pieces and trundle.)

I dont recall ever poly-ing anything before like this, so i want to attempt to do it right.

Thanks for any input.

Stephen

[Joe Chritz]

While I shall skip the question of whether poly is the best finish for a furniture piece I will say that it is almost universally easier to finish in pieces and then assemble whenever possible.

OK, I can't resist. If you are using borg poly then seriously look at other options before finishing. Once you go to a quality varnish you won't go back.

Joe

[Stephen McCreery 2]

Thank you for the info.

I know nothing of finishing. (You could tell, huh? lol) Could you tell me more about varnish? Is this something that i could pick up at the local home center and apply without HVLP or something like that?

[Prashun Patel]

Varnish is a broad category of finishes which means a hardening resin suspended in solvent. Polyurethane is a type of varnish. There are also alkyd and phenolic resin varnishes that are applied the same way as poly. Poly is better for abrasion but some think it's a little plastic-y looking. It's also incompatible with some other finishes - but it works fine on oil stain.

Most other types of finishes are combinations of varnish resins and oils (linseed, tung, or other) and solvents (naptha, orange oil, etc).

There are also water-based finishes, pure oil finishes (which are meant for raw, unstained wood) and shellac.

IMHO, the EASIEST way to a durable product is to use a wiping varnish (poly or other). Dilute the varnish in 50% mineral spirits and then you can apply with a rag (read up on the technique) (6-9 coats). If it were me, I'd finish as many of the pieces as you can before assembly.

If yr having probs with bleeding of the stain when you apply the varnish, then you might apply a seal coat of shellac to the piece. You dilute shellac to 2# (there are direcs on any can) with alcohol. If yr using poly, then you have to use a dewaxed shellac to do that (Zinsser Seal Coat is the easiest to find).

I also like to spray the last coat on (1-2 cans aerosol). This gives a very uniform appearance with minimal effort. Finding spray alkyd is hard though. Aerosol poly is easy to find.

There are more professional ways to do this, but for me (a relative newbie) it works great. If u go satin or semigloss then stir often. Purists prefer to use gloss only and then 'knock down' the finish with abrasives after the fact. It's fun but timeconsuming. If you want quick, then my advice is to just use a canned product with the desired sheen

[J. Z. Guest]

It will take more time, but do the poly before assembly. You can block off any mortises with the foam packing nuggets, tape off any tenons with masking or painter's tape. In pieces that have ends that won't show after assembly, dril a small hole in them and screw in some hooks to hang them by as they dry.

Lots of folks here don't like poly. I love it. More importantly for our furniture, it is super durable, and my wife likes the glossy finish. I think it is funny how people complain that it looks plasticky, but then they recommend to apply 6-9 coats. Two coats is sufficient for about anything. For kitchen tabletops and floors, maybe three. I apply the gloss poly with a rag without thinning it down; it works much better than a brush for me. Not as much dripping & running to contend with.

[Stephen McCreery 2]

Frustrating. I really need to get this buttoned up today. Now i have no idea what to do. The more i read about this, the more confused i get.

I have always put stuff together, but never finished it. That was for someone else.

[Jim Becker]

Stephen, don't get frustrated...it's not that big of a deal and you CAN do this with no problem.

I agree with Jeremy that pre-finishing prior to assembly is easier for certain kinds of projects and this may be one of them. It makes handling things easier and you can also work horizontal which can help with the process when you are new to it.

As to the finish itself, yes you can use 'borg polyurethane varnish (typically Minwax in the mass market) if it is all that is available to you, but a stop at a local "real" paint store, such as Sherwin Williams, Benjamin Moore, etc., will give you more choices relative to varnish products. Also consider a wipe-on varnish application method. You can buy the varnish pre-mixed for that, or simply take any oil-based varnish and cut it 50/50 with mineral spirits to make your own wiping varnish economically. Wiping on is typically easier than brushing even though it takes about three times as many applications. You wipe it on with a soft lint-free cloth or towel (dispose of properly!) and don't re-visit an area even if you make a small miss in your pass. 8-12 coats wiped on quickly will give you a nice result.

If you choose to brush, still cut the varnish just a little for better flow (they are typically a bit thick in the can these days) and use a QUALITY brush (spend some money on a good brush) to apply the finish. I like a 2" sash brush for most of the brushing I do, but that's a personal preference. You might want to practice a little on some scrap to get a feel for how the finish goes on.

When prefinishing anything that will need to be glued later, be sure to mask off the area that should not get finish on it. A little preparation goes a long way to a good job.

[Stephen McCreery 2]

The poly does say for furniture (among other things) and it should be durable. The most important thing is durable. This is a bunk bed for the kids. I want the finish to be durable.

I guess now i need to rethink (as i always do) the application. I bought Minwax fast drying poly but am wondering if i should have bought the wipe-on poly.

I don't want there to be a chance that i will ruin this piece with faulty application from a novice. I am checking out the Minwax site. Any other sites anyone can recommend?

[Prashun Patel]

Minwax is fine. Some prefer the Varathane or Cabots if shopping at BORGs.

Personally, I'd make my own wipe-on. But if u don't have mineral spirits or thinner and don't want to mix (50/50 is easiest) then just buy the wipe-on stuff.

Wiping on is hard to get wrong if you have patience. Just keep telling yrself, "go slowly", and "don't work it too hard". Some like to wipe it on and then quickly tip off with a good brush.

Did you get gloss?

[Steve Schoene]

Poly is just one of several varieties of varnishes. The consumer grade polyurethane varnishes are made with alkyd resin modified with the addition of polyurethane resin. Originally designed for floors, the polyurethane resin adds additional abrasion resistance. But, it also come with a few negative attributes. It tends to be a little hazy, if the coating builds very much, that affects the appearance subtly. Some people call that looking like plastic. It also can have adherance problems, being bothered by incompatibilities, like using stearated sandpaper or shellac with natural wax, that other varnishes can shrug off. Most importantly, in my view, is that it is more difficult to rub out to an even sheen.

Good non-polyurehane varnishes avoid the problems of polyurethane varnishes, and aside from the natural benefits of using straight alkyd or phenolic resins, appear to be better made than the home center polys in terms of flowing out evenly. You can find them in paint store

Rubbing out is important with varnish. I don't find it possible to obtain a professional furniture grade finish without rubbing out the final surface in some fashion. It dries slowly enough that dust nibs are inevitable. I think those need to be removed, as well as any preventable but not unusual application defects such as a sag, or run, or brush mark. It can be done with polyurethane varnish, but it is more of a challenge.

As a newcomer to finishing I strongly recommend the book Understanding Wood Finishing by Bob Flexner. In addition to giving some good recipes for finishing he also provides a lot of information about why things work or don't work.

[Stephen McCreery 2]

Semi-gloss. If we cant go with a semi then we will go with satin. I decided to wait until later today when i will have an extra set of hands for the big pieces. I think i want to maintain a wet edge if that is a possible issue.

How important is it that i do it indoors? I may not have a place indoors to do it.

[Jim Becker]

You can do it indoors with good ventilation while the finish off-gasses.

As to the need for "durability"...of course that's important. But know that "poly" really isn't any more "durable" than any non-poly oil-based varnish and that a better quality product will be "more durable" than a lesser quality product. Polyurethane only brings some additional abrasion resistance (important in floors) but at the expense of often having less clarity, etc., as Steve mentioned above. Hence, the recommendation to consider something from a real paint store rather than a mass marketer who sells primarily on price. Buy a good finishing product and don't buy more than you will use plus a little extra for, umm...comfort. Finishes have relatively short shelf lives after being opened and throwing it out later after buggering up the next project is more expensive than just buying in smaller quantities at a little higher cost per unit.

[Prashun Patel]

I think i want to maintain a wet edge

Another reason to 'cut' the poly with spirits. It'll keep the edge wet longer, and will flow thinner coats which'll minimize puddling.

Be careful with satin or semi poly when cutting, though. I've had bad experience with the 'declarifiers' not being homogenous enough in 50% wiping v. Used straight, I haven't had the prob. Another reason to go with a higher quality product.

I echo all the suggestions not to buy on price. You'll rue the $5 you save when you see sags, streaks or white spots.

[John Seiffer]

Dude, It's a bunk bed for your kids. I'd just finish it the handiest way you have which sounds like 2-3 coats of minwax poly (indoors or out based on what's most convenient and the weather). Then take the rest of these posts as education. While you're finishing the bed you'll be learning what you might want to do on a real fancy piece.

Once the kids have climbed on it a few times or crayoned it or put Yankee stickers on it you'll never know the difference. They'll just be glad you made them a bed.

Enjoy.

[Stephen McCreery 2]

Minwax is fine. Some prefer the Varathane or Cabots if shopping at BORGs.

Personally, I'd make my own wipe-on. But if u don't have mineral spirits or thinner and don't want to mix (50/50 is easiest) then just buy the wipe-on stuff.

Wiping on is hard to get wrong if you have patience. Just keep telling yrself, "go slowly", and "don't work it too hard". Some like to wipe it on and then quickly tip off with a good brush.

Did you get gloss?

I think i would like the wipe on better as it sounds easier to not screw up. I needed to get this done yesterday, but i get overwhelmed too easy. I was just ready to chuck the whole bed into a burn pile.

Why would a paint center have different products than a Home Depot type of place?

Could i buy Verethane and cut 50/50 with spirits and then wipe on? Would this be the same wipe on technique mentioned here? (Hand rub finish- 3 coats, 2nd with steel wool and 3rd with 400-600 sandpaper.)

As a newcomer to finishing I strongly recommend the book Understanding Wood Finishing by Bob Flexner. In addition to giving some good recipes for finishing he also provides a lot of information about why things work or don't work.

Thank you. I will get this. It sounds very interesting and helpful. Why didn't you recommend this last week so i could have ordered it and be reading it now?

Dude, It's a bunk bed for your kids. I'd just finish it the handiest way you have which sounds like 2-3 coats of minwax poly (indoors or out based on what's most convenient and the weather). Then take the rest of these posts as education. While you're finishing the bed you'll be learning what you might want to do on a real fancy piece.

Once the kids have climbed on it a few times or crayoned it or put Yankee stickers on it you'll never know the difference. They'll just be glad you made them a bed.

Enjoy.

OMG- good point.

I have some mental issues when it comes to this kind of stuff. I cant just "do" it. I have to be somewhat sure that i wont screw it up and it will turn out decent. I don't want to see something everyday that will remind me of how i failed. I certainly don't want others to see it either. I really don't want run spots and i am a bit worried about thick globby looking areas. I don't think globby is a word though. The bed looks really decent so far, i don't want to screw it up now.

Thank you all for your help and ideas. I am sure this sounds crazy too most of you but i am far from normal. That #2 pine sure would make a hot bonfire. That stain wouldn't be good for the marshmallows and hot dogs though...