Quick wood finishing question

[PWR RYD]

I'm using solid white oak to build a case for my tube preamp project. I have sanded it smooth with 100 grit, then 150 grit, and finally 220 grit sand paper. Before I apply any finish (probably just clear poly but maybe a stain) should I wipe it down with a little paint thinner on a rag, a damp (water) cloth, or just use a tack rag (cheese cloth) to remove the dust?

[maynardg]

I've seen a case where water-based poly is incompatible with tack rag residue. Never a problem if the first coat after sanding is a shellac seal coat. A damp cloth may re-raise the grain.

[donradick]

I am not a wood finish guru, but I always wipe with some denatured alcohol on a rag. Theory is that this will evaporate with no residue. Seems to work.

[arlis_1957@yahoo.com]

Paint thinner

[arlis_1957@yahoo.com]

If you looking for a very fine finish, you should fill the grain first.

[PWR RYD]

A damp cloth may re-raise the grain.


This might be a dumb question, but is it a bad thing to re-raise the grain?

[PWR RYD]

If you looking for a very fine finish, you should fill the grain first.

You mean smooth like glass?

[davepellegrene]

This might be a dumb question, but is it a bad thing to re-raise the grain?

I usually just use a blow gun or shop vac to get the dust out of the pores of the wood then stain. A little dust isn't that critical at this point because you are wiping stain off with a rag so you are either putting a little dust on with the rag or taking it off. Once the wood is sealed then it's more critical you should use a tack rag between coats. More important again is getting the dust out of the pores of the wood. Shop vac is best because you'll be blowing dust into the air with a blow gun.
As far as raising the grain your first coat of finish will do this anyway. I wouldn't use water though.
Dave

[PWR RYD]

Awesome! Thanks guys. Even though this isn't a DIY speaker project... it is still a DIY project that involves some wood, wire, a little metal fab, lots of components, etc. so I will post up some money shots :D

[r-carpenter]

This might be a dumb question, but is it a bad thing to re-raise the grain?

it's actually a very good trick if you care about finished product. Grain is raised with moist rag, let dry and then sanded very lightly (320 or so). This extra step makes the stain go on smother, less **** after the fist finish coat. Of cause with oak, staining is always problematic, but it'll help anyway.

[PWR RYD]

Yes, I do care about finished product. Thanks.

[r-carpenter]

sorry, i didn't mean to sound condescending.

[AMC]

Filling the grain is commonly done with wood like oak, if you want a completely glass smooth type of finish. If you don't seal it, the large open pores of the oak will always be there. It's just a preference thing, to each their own. Open pores will never look as glossy, if that is what your going for.

[PWR RYD]

sorry, i didn't mean to sound condescending.

Not at all, I appreciate your expertise.

For anyone interested I blew it clean with my air nozzle then I rubbed a little "golden oak" stain on it. I will post up some pictures tomorrow. I really like how it turned out! The color is just right. The wood grain looks fantastic. Now I just need to decide if I want to finish it with a satin or gloss poly finish.

[PWR RYD]

A couple of shots:

The oak case:
http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110324-00016.jpg
Another:
http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110324-00018.jpg

The top aluminum plate:
http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110324-00020.jpg

Inputs/output:
http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110324-00021.jpg

Power/fuse:
http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110324-00022.jpg

[arlis_1957@yahoo.com]

very nice craig. if you dont fill the grain, you can use many coats of poly and the wood will become level. dont be afraid to put a very thick coat on. it will take a while to cure but will fill the grain. the baffles in my avitar are white oak with golder oak stain and lots of poly followed by a good rubbing with a grey pad on my random orbit sander followed by a coat of paste wax followed by a good workout with a white pad on the sander and a buffing pad.

[PWR RYD]

Thanks Arlis. I took these pictures tonight shortly after applying only one coat of Minwax semi-gloss polyurethane with a cheap foam brush. Sometimes I like "satin", sometimes I like "gloss", but this time I think I made the right choice with semi-gloss.

I'll take more pictures as this project progresses. I think the devil is in the detail and I feel (hope) my strong suit is much more in electrical fab/wiring than woodworking :o Kind of like I know I am a much better welder than I am a wood finisher :( Each project teaches me what to do and what not to do :cool:

[PWR RYD]

A little more progress:
http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110325-00023.jpg

[PWR RYD]

One more:
http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110325-00024.jpg

[rogoll]

One more:
http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110325-00024.jpg

A very "professional" looking job, IMHO! Keep up the good work.

[David Crewe]

Looks very nice. How log till tubes glow? Is this a kit?
I would put a good heavy finish on the inside of that cab though. One of the few things I know about tube amps is there are copious amounts of heat and you don't want to dry the wood out to fast from the one side. It will cup.
David

[PWR RYD]

Thank you guys! This has been a fun project and my favorite part is still ahead (wiring). This is a scatch build and will be point to point wired. Luckily all of the heat sources (tubes) will be up on top of the plate, so no heat inside the case. A quick calculation of all of the resistor dissapated power inside the case equals less than 12 watts total.

[PWR RYD]

The top plate fits perfectly! :)

http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110325-00025.jpg

[MrkCrwly]

Your hammered silver really looks great on your top. Not sure why but I have had better luck with silver than any other color when it comes to a true hammered finish.

[Herman Trivilino]

Thanks Arlis. I took these pictures tonight shortly after applying only one coat of Minwax semi-gloss polyurethane with a cheap foam brush.

If I've been following along correctly, you've applied a coat of stain, followed by a coat of semigloss polyurethane. Are you happy with the finish, or did it raise the grain and make the surface rough? Usually they recommend a "spit coat" between the stain and the poly as a sealer to help avoid this problem. This spit coat can be thinned shellac (preferred because it dries faster) or thinned polyurethane.

Also, you can wet sand after your final coat to make it really smooth, just make sure the finish is thoroughly hardened before you take this step. (I like to use mineral spirits instead of water when wet sanding). And, to top it off, I like to apply furniture wax with #0000 steel wool. Rub it in well, as the friction will get the fibers of the steel wool to drive the wax into the pores. Let it skim over, which only takes a minute or so (you can tell by touching it if it's skimmed over). Then buff with a clean dry rag. If you let the wax harden too much before buffing, it'll be impossible to buff to a shine. Simply remove the wax with a rag dipped in mineral spirits, dry, and try again.

You can apply multiple coats of wax to get a nice shine and a very durable surface that's easier to keep clean.

[PWR RYD]

Herman here was my complete procedure:

1. sand 100 grit
2. sand 150 grit
3. sand 220 grit
4. blew off dush with air nozzle
5. rubbed on "golden oak" stain with an old sock
6. waited 10 minutes then wiped off excess stain an old t-shirt
7. next evening applied one coat of minwax semigloss poly (foam brush)
8. next evening lightly dry sanded with 400 grit
9. blew off dust with air nozzle
10. wiped down with t-shirt and paint thinner
11. applied a second coat of semigloss poly (foam brush)

That's it. It turned out smooth and even. I was temped to do a third coat... but decided I liked how it was and didn't want to chance screwing it up.

[Herman Trivilino]

That's great. Evidently, you're enjoying some low humidity? Around here, it's so humid usually that it's very difficult to get finishes to dry thoroughly.

[Soundslike]

Whenever finishing is discussed, I notice what I think is a common point of confusion:


Re: Quick wood finishing question
Filling the grain is commonly done with wood like oak, if you want a completely glass smooth type of finish. If you don't seal it, the large open pores of the oak will always be there. It's just a preference thing, to each their own. Open pores will never look as glossy, if that is what your going for.

If I understand correctly, AMC is talking about filling the little voids found in oak. If these voids are not filled, the end result is a craft-like appearance. If the voids are filled, a glassy table-top like appearance can be achieved, if that is what's desired. The darker brown indicates filler, and the grey indicated the finish material, e.g., varnish or paint.

The attached drawings depict an exaggerated example of the difference between filling and not filling.

If I were finishing a project like yours, I would do exactly what you've done. It looks great. Looking forward to the finished product.

[PWR RYD]

Now it starting to get fun!

http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110326-00027.jpg

[PWR RYD]

http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110326-00026.jpg

[PWR RYD]

Soundslike is correct. I would describe my finish more "craft like". Just my opinion, but I think it fits more with my personal DIY "home brew" look, rather than something with a billet machined anodized aluminum face I could have purchased anywhere else.

[Herman Trivilino]

If I understand correctly, AMC is talking about filling the little voids found in oak. If these voids are not filled, the end result is a craft-like appearance. If the voids are filled, a glassy table-top like appearance can be achieved, if that is what's desired.

This is my understanding, too. I understand that to get the true piano gloss finish you have to fill the pores with a paste filler. I've never done it myself, but I've seen it done and it takes a bit of skill and practice.

I don't think I've ever seen it done on a wood like oak that's open-grained.

[arlis_1957@yahoo.com]

not true. you can put many coats of poly with sanding and they will fill eventually. im not afraid of putting on a rediculessly thick coat of poly on sunday and sanding it the following friday or saturday.

looks really nice craig.

[PWR RYD]

Thanks Arlis. Hopefully it SOUNDS nice feeding a ClassDaudio 500 Watt amp. If not I'll build a big ugly space heater tube amp just to twist Pete's nippies :D

[arlis_1957@yahoo.com]

oh you just had to say that! now he will build a 1000 wpc in a server case! with redundansy!

[rogoll]

If I've been following along correctly, you've applied a coat of stain, followed by a coat of semigloss polyurethane. Are you happy with the finish, or did it raise the grain and make the surface rough? Usually they recommend a "spit coat" between the stain and the poly as a sealer to help avoid this problem. This spit coat can be thinned shellac (preferred because it dries faster) or thinned polyurethane.

Also, you can wet sand after your final coat to make it really smooth, just make sure the finish is thoroughly hardened before you take this step. (I like to use mineral spirits instead of water when wet sanding). And, to top it off, I like to apply furniture wax with #0000 steel wool. Rub it in well, as the friction will get the fibers of the steel wool to drive the wax into the pores. Let it skim over, which only takes a minute or so (you can tell by touching it if it's skimmed over). Then buff with a clean dry rag. If you let the wax harden too much before buffing, it'll be impossible to buff to a shine. Simply remove the wax with a rag dipped in mineral spirits, dry, and try again.

You can apply multiple coats of wax to get a nice shine and a very durable surface that's easier to keep clean.

Just FYI... I know this is an amp, but I imagine the same holds pretty true... I've been told not to use steel wool in this hobby because the fine wires that you inevitably miss can get drawn into the voice coil and magnets and cause trouble.

[Herman Trivilino]

Just FYI... I know this is an amp, but I imagine the same holds pretty true... I've been told not to use steel wool in this hobby because the fine wires that you inevitably miss can get drawn into the voice coil and magnets and cause trouble.

Ouch! I hadn't thought of that. Thanks for that tip.

[davepellegrene]

Just FYI... I know this is an amp, but I imagine the same holds pretty true... I've been told not to use steel wool in this hobby because the fine wires that you inevitably miss can get drawn into the voice coil and magnets and cause trouble.

I learned that the hard way. I was using steel wool on a finished speaker and happened to notice all the fibers were sticking to the cone. That was not an easy job trying to get them off. I finally had to use my shop vac.

Dave

[PWR RYD]

I decided not to point to point wire the entire preamp. So I built this little perf board for the power supply HV filter and the filament rectifer/filter. I guess technically it is point to point wired on the backside.

http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110402-00032.jpg

[PWR RYD]

Ok, here is my first attempt at point to point wiring. This is just the power supply circuits. My first inclination was to force all the wires into nice straight lines with crisp 90 degree bends so that everything looks super clean and square. But after starting it felt more easy/natural on the stranded wires not to bend them so sharply and just kind of let things flow.

http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110402-00034.jpg

[Herman Trivilino]

Beautiful workmanship. I regret not having learned more about electronics when I was younger. Your work inspires me. It's never too late ...

[djg]

Yes, that is very nice wiring.

[PWR RYD]

Thank you! This has been a very fun project. When this one is done.... I want to build a big 500 watt ClassDaudio amp, then a few more speaker projects, then a big 30-40 wpc push-pull tube amp, then a few more speaker projects.... will it ever end??? :)

[Herman Trivilino]

.... will it ever end??? :)

Let's hope not!

[Soundslike]

Really, really nice work. If it sounds as good as it looks, you're going to be in heaven. Well done..

[Starkiller4299]

Your cable-fu is strong.

[PWR RYD]

Got the B+ and heaters wired:

http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110405-00035.jpg

[PWR RYD]

http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110405-00036.jpg

[gabel87]

This might be a dumb question, but is it a bad thing to re-raise the grain?
Raising the grain is actually a good thing. The way I was taught to prep most wood for finish, not as big of a deal with really hard woods like oak and walnut, was to sand with 120 and then wet with a foam brush to raise the grain then sand with 220. Tack clothes can be sketchy leaving stuff behind. I vacuum and then wipe good with a lint free cloth. High pressure air is good after that. Dry fast evaporating spirits are probably fine too. Edit, yeah that is some sweet cabling. I do control wiring, getting all your soldiers in a row is the mark of fine craftsmanship. Soo much easier to work on later too, see what's what.

[PWR RYD]

Life has been busy. I still need to wire the inputs/outputs. But here is where it's at right now:

http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110428-00051.jpg

http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110428-00052.jpg

[Herman Trivilino]

I'm in awe of your craftsmanship. Did you design the circuit, or are you working from someone else's schematic.

[50 watt head]

Craig, it all looks great -- wiring, wooden case, chassis work and finish. Nice work!

Is that Hammond iron?

[PWR RYD]

Is that Hammond iron?

Yes and I am very dissatisfied with their quality! The lamination stack is not square and I had to pull off the end bells, sand blast them, and repaint because their paint rubbed off with my finger nail (no effort). My next tube project will use Edcor iron or Triode Electronics iron.

Thanks for the compliments. Like any and all projects... there are several things I would do differently the next time.

[50 watt head]

Yes and I am very dissatisfied with their quality! The lamination stack is not square and I had to pull off the end bells, sand blast them, and repaint because their paint rubbed off with my finger nail (no effort)

I was never completely happy with Hammond power xfrmrs, either. The 115v primary was always a pain, and they tended to be mechanically noisy.

[PWR RYD]

I'm in awe of your craftsmanship. Did you design the circuit, or are you working from someone else's schematic.

Thank you. I only designed the power supply circuit. The audio circuit is called the Aikido Cathode Follower. Here is a link:

http://www.tubecad.com/2010/06/blog0188.htm

[PWR RYD]

I just finished all of the wiring:

http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110501-00056.jpg

Much more work than I expected but I'm pretty happy with how it turned out.

[PWR RYD]

Cranked her up for the first time, after careful power up checks first of course. It sounds great playing U2 Joshua Tree with my Rotel 60 wpc amp and G-Dog speakers. That Sony CD player is a pawn shop $20 special. I can't say it makes everything it's hooked up to sound mystical or magical, but I do have to brag a little that it is dead silent. No hiss and absolutely no 60/120 Hz hum. I'm going to hook it up to better speakers and source and see how I like it. Big thanks to Tom on this forum for the 6DJ8 tubes and lots of other parts and pieces.

http://i1138.photobucket.com/albums/n531/PWRRYD/IMG-20110501-00054.jpg