An ionizer simply adds a charge(d) particle to an atom / molecule. That charge allows it to attract or be attracted to, other particles. This cause it to "bond" and not freely associate. Charged dust molecules "bond" with each other and form longer chains which cause them to be effected by gravity sooner, and / or allow them to be caught in "Hepa" filters more readily. Hepa filters work better when they are semi-dirty and charged with ionized particles.
From my mold classes........
Ron
(I don't eat mushrooms since this class)
From my mold classes........
Ron
(I don't eat mushrooms since this class)
For me it is a waste of time doing the "Piano Black" finish, however I know that it is a rite of passage to some in order to prove that they can do it. Life is too short to spend so much time on this sort of finish. Mirror black finishes show up every fingerprint and speck of dust and scratch and unless you use some sort of 2-pack catalytic paint which has some degree of hardness you will always have to take great care in how you handle your speakers and how you clean them.
(Bearing in mind that I have been a professional decorator for 28 years and have done more sanding down of paint and wood finishes than you can possibly imagine and therefore have developed a degree of antipathy towards the sanding down process)
(Bearing in mind that I have been a professional decorator for 28 years and have done more sanding down of paint and wood finishes than you can possibly imagine and therefore have developed a degree of antipathy towards the sanding down process)
Hi all,
I've read through most of this excellent thread and am currently applying the primer to my new cabinets and sanding back.
My question is, how "perfect" does the primed surface need to be?
I'm having trouble sanding back and eliminating the pits, without finding I'm going through the primer altogether and exposing the MDF substrate.
Because the primer is so fine - it comes out of the spraycan almost like a vaporous mist - it never really builds up any significant thickness. Its also devilishly hard to tell where its been sprayed on and where it hasn't.
By the way... I'm already completely amazed that someone like me, who has only ever slappped paint onto walls - can follow these instructions and fairly easily achieve what is starting to look like a pro finish! This thread delivers!
Hi Billyo
It needs to be pretty good. I get mine virtually perfect and it makes the other steps easier. The thing you want to avoid is exposed mdf. What your aiming for is a smooth glass like finish covering the whole of your enclosure.
You could try dry sanding if your encountering this issue, wet sanding will cause all sort of problems otherwise.
Be methodical in the way you spray. Consistent horizontal strokes starting from the top of the work and overlapping by about 50% is good for me. This way you don't need to see where you've already been.
Billyo,
spray a slightly thicker coat of primer/shellac. If you first spray horizontal, with 50% overlap strokes, then vertical with 50% overlaps, you'll have a higher build which won't sand through as easily. 150 -180 grit wet/dry on a sanding block. Watch for burn through on the corners/edges.
Tip:
spray the outside corners first, then spray the bulk/faces of the project with overlapping strokes, that way you are sure you have enough primer on the edges where paint is thin to begin with. Be patient with yourself and go sloooowww. It's a long process that doesn't take well to being rushed.
Are you using a W/B or Oil for the top coat?
Ron
spray a slightly thicker coat of primer/shellac. If you first spray horizontal, with 50% overlap strokes, then vertical with 50% overlaps, you'll have a higher build which won't sand through as easily. 150 -180 grit wet/dry on a sanding block. Watch for burn through on the corners/edges.
Tip:
spray the outside corners first, then spray the bulk/faces of the project with overlapping strokes, that way you are sure you have enough primer on the edges where paint is thin to begin with. Be patient with yourself and go sloooowww. It's a long process that doesn't take well to being rushed.
Are you using a W/B or Oil for the top coat?
Ron
I might have to give it a go, it seems harder to find Glatex 8 these days. A two part acrylic I love, it even comes in some rad colours. It totaly plasticises the outside of the wood and is so watertight they use it to seal woodwork on yachts. I've had some outstanding results just useing a high density foam roller. Also what is great about it is that the sanding period comes pretty soon after applying, but it is also quite short. Sanding afterwards makes the clear turn a slight gray, anyway, you can see it if you try it, so if you ever find it, follow the instructions on the can or else....
I need to do a high gloss finish on the faces of the boxes I will use for my goodmans.
I need to do a high gloss finish on the faces of the boxes I will use for my goodmans.
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It's been decades since I did any fine finishes, but primer, even spray cans [typically Krylon brand], was anything but 'fine'. Hopefully, the 'greenies' haven't gutted it. Regardless, conventional wisdom dictates shooting several coats of a dark primer first, let dry, then only as many coats of a light color primer for it to look uniform and block sand down till you start seeing the dark peek through, stop, clean/tack rag it and shoot some more dark, etc. and at some point you'll get a glass-like, uniform solid dark color after sanding off all of the latest coat. You should never sand down to the substrate. If this is a problem, then it needs [more] leveling/smoothing over before priming. If your finish color needs a light primer base, then reverse the color pattern.
Some folks do a so-so prep job and use many blocked/hand rubbed/whatever color coats, but IME only very high solids finish coatings can match a proper prep job [learned this the hard way doing a hand rubbed black lacquer finish on a '23 'T' bucket roadster, starting over after 27 coats still didn't look completely glass-like], so labor and budget wise it's a 'pay me now or pay me more later' situation.
GM
Thanks for the replies everyone 
Today I went to the hardware store and got a different primer - this one seems to be a thicker (they are both oil based - by the way) - its also twice as expensive @$10 per can and will barely cover 1 speaker to a couple of thin coats on top of the original cheaper stuff. This project has cost a motza so far! I've blown the estimated cost at least 2x with all of the little extra expenses and tools
I can definitely see how getting a compressor and gun can work out cheaper - unfortunately I dont really have the space or WAF for a hulking great barrel in my garage.
Will attempt for the 3rd time to get a pit-free primed surface tomorrow evening.
Alarmingly, some moisture got in when I was wet-n-drying the old primer and touched the MDF at a place where I went through the old stuff, and caused a swelling. I sanded it back, but its still quite visible, even under the new primer... I'm concerned that I've permanently blemished the MDF. Any tips for repairing this little patch? Will the MDF dry out and still be workable?
Digits - the idea of using a roller is intriguing - do I understand you right? You've not sprayed the primer, but rolled it on instead?
Today I went to the hardware store and got a different primer - this one seems to be a thicker (they are both oil based - by the way) - its also twice as expensive @$10 per can and will barely cover 1 speaker to a couple of thin coats on top of the original cheaper stuff. This project has cost a motza so far! I've blown the estimated cost at least 2x with all of the little extra expenses and tools
I can definitely see how getting a compressor and gun can work out cheaper - unfortunately I dont really have the space or WAF for a hulking great barrel in my garage.
Will attempt for the 3rd time to get a pit-free primed surface tomorrow evening.
Alarmingly, some moisture got in when I was wet-n-drying the old primer and touched the MDF at a place where I went through the old stuff, and caused a swelling. I sanded it back, but its still quite visible, even under the new primer... I'm concerned that I've permanently blemished the MDF. Any tips for repairing this little patch? Will the MDF dry out and still be workable?
Digits - the idea of using a roller is intriguing - do I understand you right? You've not sprayed the primer, but rolled it on instead?
primer and finish, some people paint cars this way with rustoleum...
http://www.club80-90.co.uk/pages/downloads/tech/paintfor%A350.pdf
http://www.club80-90.co.uk/pages/downloads/tech/paintfor%A350.pdf
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So no need to get the primed surface perfect then? Given the orange peel from the color that will be going on, it did seem to be unnecessary to get a pit free primed surface.I was aiming for it pit free but wasnt going to polish - glad (in fact, overjoyed
) that its not needed in the first place.Taking a week off with the family and going to Cairns - will continue on when I get back...
Just a quick note. I have painted a few cabinets in the past, to very unsatisfactory results. I have now followed Shinobiwans method and have a primer layer on MDF - from spray cans - (taken from 400 to 1000 grit by hand wet-sanding) that reflects.
That's not important in itself but I have to say that pure common-sense and elbow-grease yields fantastic results. I am not finished, nor have I even applied a color-coat but I have to say that Shinobiwan's method is magnificent. Perhaps I will fail on the piano-black but so far it looks great. We'll see...
I understood that he said that the foundation is everything, but maybe I took it too far. I couldn’t help it.
I sealed my MDF cabinets with alcohol based sanding sealer, then sprayed them with a million-dollars worth of Krylon spray black primer and then sanded them down by hand. It has taken two weeks but the result is amazing.
I started by using my sander but since spray cans put such a weak layer down each time I wound up re-spraying until I covered the burn-thru that each sanding session exposed. I do have a compressor and a gun but I was egotistical and thought I'd do just as well with cans - not. However, I am committed now and have carried thru with the method I started with.
I have learned that I want to hand wet sand the whole process (takes more time up front but results in less re-spray time because you take off less material each time) and I also enjoy it. I used a Makita, like Shin, but I have found that hand-sanding takes less paint off each time. Saves time in the end if you actually hand-sand it. Maybe because I have a testosterone-heavy sander.
The next cab I paint will take *far* less time.
No wonder people charge so much money for this finish - it is all about labor and time dollars.
I will post pictures when and *if* (failure is still a very real option) I achieve a good final finish but I have to say that I have never before had a *primed* surface that has been glass-smooth and reflective.
Even if the primed surface is imperfect in many ways it still reflects the world and I have never before had that happen. It is a result of pure labor and common sense method.
I may yet fail and have a less than excellent result but I have learned so much in the process. If this method does fail, then I will step up the process and try with better tools - but - if I succeed it'll be a pretty cool lo-tech solution. Hi-labor, lo-tech, wicked finish.
I am foolishly hopefull.
Thank you Shinobiwan, many times. Live long and prosper.
Best Regards,
Tom
That's not important in itself but I have to say that pure common-sense and elbow-grease yields fantastic results. I am not finished, nor have I even applied a color-coat but I have to say that Shinobiwan's method is magnificent. Perhaps I will fail on the piano-black but so far it looks great. We'll see...
I understood that he said that the foundation is everything, but maybe I took it too far. I couldn’t help it.
I sealed my MDF cabinets with alcohol based sanding sealer, then sprayed them with a million-dollars worth of Krylon spray black primer and then sanded them down by hand. It has taken two weeks but the result is amazing.
I started by using my sander but since spray cans put such a weak layer down each time I wound up re-spraying until I covered the burn-thru that each sanding session exposed. I do have a compressor and a gun but I was egotistical and thought I'd do just as well with cans - not. However, I am committed now and have carried thru with the method I started with.
I have learned that I want to hand wet sand the whole process (takes more time up front but results in less re-spray time because you take off less material each time) and I also enjoy it. I used a Makita, like Shin, but I have found that hand-sanding takes less paint off each time. Saves time in the end if you actually hand-sand it. Maybe because I have a testosterone-heavy sander.
The next cab I paint will take *far* less time.
No wonder people charge so much money for this finish - it is all about labor and time dollars.
I will post pictures when and *if* (failure is still a very real option) I achieve a good final finish but I have to say that I have never before had a *primed* surface that has been glass-smooth and reflective.
Even if the primed surface is imperfect in many ways it still reflects the world and I have never before had that happen. It is a result of pure labor and common sense method.
I may yet fail and have a less than excellent result but I have learned so much in the process. If this method does fail, then I will step up the process and try with better tools - but - if I succeed it'll be a pretty cool lo-tech solution. Hi-labor, lo-tech, wicked finish.
I am foolishly hopefull.
Thank you Shinobiwan, many times. Live long and prosper.
Best Regards,
Tom
Well, the top coat manufacturer should have some instructions WRT prep work and I previously noted I haven't shot a show car quality finish in decades now, but historically a topcoat requires 'X' amount of surface area to bond to and all the fine scratches of 400 grit [600 max depending on primer] adds a considerable amount. Also, at some point the primer's structural integrity breaks down to the point where the topcoat has to etch it to bond to it and why wet sanding it is not a good plan unless shooting epoxy or similar.
As I found out today WRT the various exterior primers/top coatings, etc., there's been a tremendous change in coatings for various reasons since I last got serious about house rehab ~34 yrs ago and not all IMO are overall for the better, but gov'ts. and the self righteous are determined to protect us from ourselves no matter the cost, so looking forward to seeing how yours turn out.
At this point, scoping out what, if any, top coatings are designed for such a smooth prep job and/or what precautions and/or intermediate sealer may be required to ensure a beautiful, durable finish using whatever top coating you prefer seems a good plan. Sure would be a shame to see all that time/effort be for naught if my ancient experience is still valid.
GM
As I found out today WRT the various exterior primers/top coatings, etc., there's been a tremendous change in coatings for various reasons since I last got serious about house rehab ~34 yrs ago and not all IMO are overall for the better, but gov'ts. and the self righteous are determined to protect us from ourselves no matter the cost, so looking forward to seeing how yours turn out.
At this point, scoping out what, if any, top coatings are designed for such a smooth prep job and/or what precautions and/or intermediate sealer may be required to ensure a beautiful, durable finish using whatever top coating you prefer seems a good plan. Sure would be a shame to see all that time/effort be for naught if my ancient experience is still valid.
GM
Primer is NOT waterproof, RTFM. Automobile primer, which is meant to be applied to metal does not swell like MDF. Your pressing your luck if you wet sand primer over MDF.
1000 grit? Why? More is not always better.
Ron
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