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Discussion Starter #1
Hey guys,

I have recently moved to Germany and couldn't bring my BOC screen with me. I need a new one, and want to make something snazzier!

My projector is the Epson TW-600 (Pro cinema 720 or something in the US?) w/2000 hrs on low lamp mode. This is a model with a quoted max lumens of 1600, I believe. Projection distance will be ~3.5 m = 11 ft or so from a table or shelf. Projection will be into the corner of a 6 m x 5 m room with white ceiling, yellow walls, and tiled floor. I am renting so cannot paint the walls, but I will buy fabric to black the floor, left wall, and ceiling. Screen size is not fixed at the moment - but I want at least 2 m width for 16:9 and some additional width for 2.4:1.

Ok! I have already asked for paint advice on AVS but thought that I should ask you guys as well. As a physicist I respect your scientific approach, and I also know that you're working on mix equivalents for Europe. One thing that is important to me now is blacks. I hate noticing digital grey around the borders, like I did with BOC. But I don't want to go into high lamp = high noise mode, since the audio suffers. If this means that I should try for a smaller screen/closer throw, that's a compromise that I can make. I should mention that I've sourced Wilsonart laminate but they want ~$US140 for a 2330x1330x0.8 mm piece, which is high. Since I will have to move every 2 years I thought that buying a Wagner W 550 would be a good option, since I can quickly make new screens. They are $US100 here . Btw, I have 100% (Batmobile-style) external light control and like to watch in the dark.

So what do you guys think? I know that AAA is available here, and I can get Bermuda Beige mixed in some local paint brand, but I'm worrited that N7.5 is too dark for low lamp mode. How far along are the C&S and Scorpion European eqiuvalents? Or would you suggest simply a "Snow Field" Dulux w/poly or something like that. I can't get Dulux Lumitec but the brand exists here. If I go for a tint+poly, how do I know if the poly is the kind that yellows or the kind that doesn't? i.e., how would I look for a Minwax equivalent?

Substrate will probably be 1 sided Masonite on 3 mm hardboard.

Phew! I hope that's neither too much nor too little information...
 

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Hi Sam; welcome to the forum!

If you're not happy with a BOC screen because of gray blacks I don't think a white laminate screen would give you any better blacks. Mech can give you details on WA Fashion Gray laminate.

Since you are going to be watching only in the dark, and are going to even control light bounce from the walls and ceiling, that means you need a gray screen to increase apparent image contrast. How deep a gray you need is a subjective thing. I really like to have the blackest blacks I can get so I prefer the N7.5 BW.

Using PJCentral's calculator with data for the Epson PowerLite Home Cinema 720 (here) I think you could go with Black Widow even if your lamp is half as bright as it was when new.

With a 200 cm diagonal 16:9 AR screen (174 cm wide, 98 cm tall) I'm getting 32 fL. with the PJ 3.35 m from the screen and a zoom setting of 1.57x. Changing to 2.4:1 AR and zooming the PJ to 2.11x will give the same image height as the 16:9 image with a new width of 236 cm and a diagonal of 256 cm. The brightness at 2.4:1 AR would be 24 fL. At least two people are happy viewing a BW screen with 12 fL. of PJ illumination (myself and mech) and I believe others have said so as well. Personally, I could use BW at 8 fL.

A panel of what I hope will become the Cream&Sugar International mix has been sent to mech for gain testing. This should also do well for making the Scorpion mixes, but those are still untested. This summer has been crazy for all the mix developers here so we haven't done near as much testing as we had planned on doing. It is frustrating for us too.

There is nothing wrong with trying a plain neutral gray paint as a screen. The paint used should have just a hint of sheen to it. In the States we have found the Valspar and Behr flat latex enamels to have that.

I haven't tried adding water-based polyurethane to paint other than when I made my Silver Fire screen and did testing of RS-MaxxMudd. Both of these hot-spotted for me quite badly.

If I were going to try adding a clear medium to regular paint I would use acrylic artist's medium. This is a clear acrylic designed to change the gloss level of acrylic artist paints and to act as a thinning agent (depending on the viscosity of the medium used). Liquitex is a brand of artist paints and mediums that is available internationally. They are a bit costly, but many times you can find them heavily discounted. It comes in both Gloss and Matte. I would use the Gloss Medium alone since I remember someone at AVS saying they made mixes with both glossy and satin poly and they couldn't see the difference. You could of course mix the Gloss Medium and Matte Medium together to get intermediate levels of gloss, but I doubt it's necessary. That is just a guess though since I haven't tried it.

If you addressed a question to me, wbassett or mech at AVS please ask it again here. We don't participate in the DIY Screen forum at AVS anymore, it simply isn't worth the hassle (a long story and not for this forum).
 

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A panel of what I hope will become the Cream&Sugar International mix has been sent to mech for gain testing. This should also do well for making the Scorpion mixes, but those are still untested. This summer has been crazy for all the mix developers here so we haven't done near as much testing as we had planned on doing. It is frustrating for us too.
I did get your package yesterday harp. I didn't know there was an international test in the package or I would've opened it up last night. I'll start on it tomorrow when I finish up gain and pictures of the other tests. :T

Welcome to the Shack Sam! I have yet to check on the adding 25% polyurethane claims. My hunch has always been that it would add more bad than good. But like I said I haven't checked it out. It has been on my 'to do' list for quite some time. Plus, if you're adding that much polyurethane, why not skip it and go to the next sheen level? I have a lot on my plate right now and I will probably take a break after finishing. But I can see this being next on my list. It would go hand in hand with the mylar tests as well. :T
 

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Discussion Starter #4
The situation with lumens has always been a little vague for me. For the video/color optimized modes these projectors tend to only spit out 300-400 lumens, right? Not the lofty 1200-1600. Does the projector calculator take this it account? I guess it must because 400/4x8 ft^2 ~ 17 fL which is the right order of magnitude.

I had Wilsonart samples delivered and noticed tremendous pop from the DW, too much I thought. FG was hard to tell because the sample was too small - I don't think they're cost effective in Germany anyway.

That's interesting about the sheen/poly with neutral grays. A flat latex enamel should be easy to find.

But BW! If I have the brightness on low lamp to get away with it, that would be pretty nice. 2 ingredients - I like that. If I need to sit slightly closer to a smaller screen, in order to get image pop, that would be fine. At the moment I'm stuck with projecting on a dull beige colored cotton mattress protector. Definitely dimmer than 'white', and yet my blacks are still not deep enough.

Whatever I do, would you agree that spraying is the easiest solution?
 

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The situation with lumens has always been a little vague for me. For the video/color optimized modes these projectors tend to only spit out 300-400 lumens, right? Not the lofty 1200-1600. Does the projector calculator take this it account? I guess it must because 400/4x8 ft^2 ~ 17 fL which is the right order of magnitude.
I simply use the lumen estimates from the PJC calculator with a screen gain of 1.0 to make recommendations. I reduce the lumen figure by 25% to adjust for low-lamp/econo mode since that is about what the PJ's I have seen both values for run. As to how much brightness is actually lost due to lamp aging (I still want to call it a bulb :)), I have never seen hard figures for this. I do own an inexpensive (~$40) light meter that measures directly in Lux (which is easy to convert to foot lamberts) so I can know how bright my PJ is in both modes, and how much brightness my own PJ lamp loses during use.

This brings up a case in point of the subjectivity of what makes a viewable screen. A member here (Quantum) built a large screen out of vinyl flooring (there is a thread on it here), but because his screen was so large he was worried about having too dark a mix for his PJ. I forget the particulars now, but he tried an experimental BW mix that gave him a neutral N8 screen with the reflective properties of BW. It turned out that he thought it was too dark. He went with a C&S screen (N9) and is happy. Now the reason I brought this up :), I loaned him my light meter and he was getting a true 12 fL. of screen illumination. At this level I would have been happy with a N7.5 BW screen, but Quantum liked his screen brighter. There was no wrong or right here, just personal preference.

I had Wilsonart samples delivered and noticed tremendous pop from the DW, too much I thought. FG was hard to tell because the sample was too small - I don't think they're cost effective in Germany anyway.
It may help to try and define what you mean by "pop" since it does mean different things to different people. I call "pop" the richness and saturation of color that I get with a gray screen over a white screen.

That's interesting about the sheen/poly with neutral grays. A flat latex enamel should be easy to find.
Be careful since different countries use different sheen standards and a neutral gray may be harder to find than you think. I'm not sure what the German standards are. BTW, what color system does Germany use for house paints (NCS, RAL etc.)?

The theory behind adding clear medium, such as poly, to a screen mix is that it will increase the gloss level of the mix and make a more translucent mix. The theory is that the more translucent mix will provide more "depth" to the image. Since I haven't tested this theory I can't tell you if it works or not, but I do know that it doesn't take much opaque paint to block light transmission (see mech's mirror experiments).

But BW! If I have the brightness on low lamp to get away with it, that would be pretty nice. 2 ingredients - I like that. If I need to sit slightly closer to a smaller screen, in order to get image pop, that would be fine. At the moment I'm stuck with projecting on a dull beige colored cotton mattress protector. Definitely dimmer than 'white', and yet my blacks are still not deep enough.
I honestly can't tell you BW will work for you, all I can say is that I think it would work for me in your situation especially if you could reduce screen size if necessary. You would probably be surprised how dark that beige "screen" is. :bigsmile:

Whatever I do, would you agree that spraying is the easiest solution?
Personally, I would say yes, BUT practice on something else before you spray your screen. Get some cheap latex paint and use it to find out how thin you must make your mix before it will spray well through the Wagner. Also set up some large cardboard, or other cheap expendable material, and practice your spraying technique. It isn't rocket science, but it is a learned procedure.
 

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Discussion Starter #6
Sorry for the delayed reply, work has been full on for the last few days!

I think you're right that BW would suit me - I've realised that I even use low brightness on my monitors. And I read on PJcentral that they do account for video optimized lumens.

By 'pop', I guess that I meant the radioactive glow that wbassett had mentioned. DW seemed too bright for me.

In Germany, I think that NCS (S0907-y70r) is used, because I saw a thread on a German forum about Black Widow. It gets around!

The AAA is not a problem, but I guess that the base might be. It seems that different hardware stores have their own brands of paint. Maybe I can use the German Dulux... That's something that I will need to find out more about.

For the next week I'll be busy with a conference, but the plan is to get building after that. If I want to try C&S in the future than I could buy some more hardwood - the Wagner+respirator is going to account for a lot of the cost here anyway.

It's exciting - I just need the time to DO it!
 

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Ok, so I've returned from a conference, and I now have my substrate. 3 mm thick MDF with white laminate material on one side. Similar to DW in appearance but hotpots fairly bad by itself. The largest sheet that we could fit in the car was 2.3 x 1.1 m. Since this will only be ~80" for 16:9 material, I should have plenty of lumens for BW.

So I'm about to buy my Wagner from Amazon, find AAA, and get my Bermuda Beige mixed. Unfortunately, since the paint brands are different here, I have some anxiety about this. On the German thread about BW they used a brand of paint here called 'Alpina', which is a water based matte paint with Polyvinyl acetate. A quick google search tells me that this binder is the cheaper one - do I need to find the equivalent of "100% Acrylic"?

The one I'm looking at is for indoors. I'm unsure whether I should go for indoors or outdoors...

Is there anything else that I should be careful about when it comes to the base paint? I read the long comparison of bases from Tiddler. Since it makes a different, I don't want to do something wrong and have to start all over again.
 

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OK, first about the color; if you can get your paint in NCS S0907-y70r you should be good. This color either matches PPG Bermuda Beige or is extremely close. OR If you can have your paint computer matched to a color sample (the store measures the sample color with a spectrophotometer), I would be happy to send you a small piece (about 2 inches square) of 1/8 inch thick hardboard painted with Bermuda Beige so you can take it to the paint store to be matched, just PM me an address to send it to.

The MDF with white laminate on one side will make a good painted screen, but I personally would probably prime and paint the uncoated side. The reason is that in my experience it is easy to scratch off the dried paint from the laminate. Don't get me wrong, the paint won't fall off by itself, but it will be much more susceptible to damage than the MDF painted with a primer and then the BW. This, of course, it totally up to you; I understand not wanting to prime if you don't need to. Another plus about painting the "back" side of your sheet is that by doing so the unpainted laminate side would help to keep out atmospheric moisture and help prevent warping of the panel.

Tiddler sent me a large number of samples of painted hardboard and cardboard including samples of his BW clone tests. It does make a difference which base paint is used, some hide the aluminum flakes more than others, but the aluminum was visible in all of them. It does raise a question about what base is best for a screen paint. There still is no simple single answer though because it depends on what attributes you use to define "best". My guess would be that the "lesser quality" house paints might not cover as well as the "higher quality" house paints, this would actually be a good thing when using such paint to make a reflective screen mix since more of the reflective particles would be active in the final screen. I think this may have been what Tiddler was seeing in his tests.

Most definitely go with a WATER-BASED MATTE paint, especially when making a smaller screen (by PJ standards). I also would use in interior paint instead of an exterior, the exterior paints have chemicals in them for fighting mildew and such that the interiors don't and there should be less "environmental chemical pollution" from an interior paint. This would be of most importance if there are small children in the house where the screen will be.

Also, be sure to mix the BW thoroughly to disperse the aluminum particles throughout the mix. The best thing we have found is to use a "squirrel-cage" type mixing attachment and an electric hand drill.
 

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So I'm about to buy my Wagner from Amazon, find AAA, and get my Bermuda Beige mixed. Unfortunately, since the paint brands are different here, I have some anxiety about this. On the German thread about BW they used a brand of paint here called 'Alpina', which is a water based matte paint with Polyvinyl acetate. A quick google search tells me that this binder is the cheaper one - do I need to find the equivalent of "100% Acrylic"?
Here in the UK we have used vinyl paint without problems. one of the users actually tried the the s0907 in an acrylic base and was happy with the results also.
 

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Discussion Starter #10
That's good news about the vinyl paint, and very generous with the sample offer! My girlfriend flies in to Germany on Wednesday - while she's sleeping I can go and check with the local hardware store re:NCS mixing. I'm fairly confident on that front.

I'm thinking twice about priming now - the reason I went for the one-side laminated 3 mm MDF was because I had the impression that painting on the wood can lead to warping. If warping won't be a problem here... Would I roll the primer, or is it a good opportunity to practice at least one coat with the Wagner (i.e. mixture of rolling and spraying)?

Re: the spraying. I guess this is something that I need to do outside. Do you just prop the screen up in the drive way or something? There's a one car garage here but I doubt that my landlord's wife would be happy with me spray painting in there. I'm curious about how much mess this makes.

Based on 4 oz of paint per 1x4 ft squared area, I would expect to need about 22 ounces of BW. This leaves me probably needed to buy 2 x 4 oz or, for a little more, 16 oz of AAA. In either case I can expect to have paint left over. Maybe it would be cost effective to try spraying without a primer. Should I scratch the screen by accident, I could try painting the back side with better technique... How well does BW (or it's ingredients separately) keep? Can one store it?
 

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Honestly, I wouldn't expect 3mm MDF to warp due to being painted with a water-based paint, especially if using an HVLP sprayer; but it would be my luck that if I said it positively won't warp, the thing would curl like a potato chip! :doh:

What causes warping is when one side of a wooden panel absorbs more water that the other side. A old carpenters trick to flatten a warped cupboard door is to place it on dry ground with the warped side facing the ground and then wet the other side with water and place it in direct sunlight. Many times one side "warping" will correct the original warp.

In the case of thin man-made sheets like MDF or tempered hardboard, these can "warp" due to leaning them against a wall at an angle, this type of warp can be corrected by simply reversing the sheet and placing it at the same (or steeper) angle and waiting a few days.

When I have sprayed my screens and test panels I have simply screwed them to the wall of my shop. :bigsmile: This wouldn't work if your screen has already been cut to final size and you can't cover the screw holes with trim. The other system I have used when spraying glass panels is to screw multiple screws into my wall in a straight line, but leave enough of the screw sticking out from the wall so I can set the glass panel on them. You DON'T want to try spraying your screen with one edge on the ground! That is a SURE way to get dirt/dust onto the wet screen and the edge near the ground would also not get the same amount of paint as the rest of the screen.

Mech will have to give you instructions on using the Wagner HVLP, but as a rule it has minimal over-spray so I would think you could spray in a garage. With my compressor-based HVLP gun, paint only gets on things within about a foot of the screen I'm painting due to over-spray or bounce-back (paint bouncing off the screen into the air), and that is in the form of a dust that is easily wiped off. With a conventional high pressure spray gun literally everything in the room would get a coating of paint including you!

Practice using the wager with some cheap paint. This will teach you how thick the paint should be to spray and let you get a feel for how much paint the gun puts down and how fast it does so. Paint large pieces of cardboard or some other cheap throwaway material.

The standard mix of 1 quart of paint tinted Bermuda Beige plus 8 fl.oz. of AAA-F makes a total of 40 fl.oz., that should give you enough paint for spraying another coat or two if needed.

Black Widow stores just fine as long as the container is air-tight. It will stay good just as long as the latex paint used to make it. While I guess there is a time after which it "goes bad", I have some mixes several years old that are fine. As with any paint, the less air in the container with the paint the better.
 

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Discussion Starter #12
Hey! Sorry for the delayed reply. Things have been hectic since my girlfriend arrived in Germany last week...

Still, my 8 oz of AAA are in the post as we speak and I'm going to try and get the BB mixed ASAP. Unfortunately everything is a bit hard in Germany (no car anymore, for instance). On my last trip to the hardware store I had fun working out what primer is called here. :wits-end:

I've been sitting on some ebay bids for Wagners as well. Since they're a lot more expensive here I'm hoping to save a few pennies. My supervisor/landlord is confident in his rolling abilities so I guess that's a possibility if Wagner+respirator is too pricey for me.

If we were to end up with roller marks and decided that spraying is better, would these disappear if we sprayed over the top? Or is the paint not thick enough?
 

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Okay, some more time in Germany has passed while I've been sourcing and waiting for stuff to arrive... BUT... I think that I'm almost there. I now have my Wagner, AAA, and 3M respirator. And I've checked that the local store can tint the base paint for me. If I can convince my supervisor to help me cut and build the frame this weekend, I should have my BW screen up in just a few days!

One loose end for me now are whether or not I attempt to apply a primer first to my 3 mm white-on-one-side hardwood. When I look for primer in the hardware store I only see 10 L tubs, which would be overkill. If I do find a smaller can and decide to prime first, would I have to wait a few days for the paint to cure before I spray BW over it, or would I be able to do it all on the same day? How about bugs/flies? The more painting I do, the more likely it is that they'll get on the screen - is it easy enough just to pick them out?

My Dad thought that if I rub the laminate with steel wool or sandpaper it might hold the paint a little bit better. Is that a common thing to try?

I still have a couple of naive questions as well. I'm been looking for these squirrel cage paint mixers but haven't see one so far... if I can't find one can I just mix it by hand? Bubbles shouldn't be a problem, I suppose, since I'm spraying...

Do you have to be careful about the paint drying/evaporating while you mix it, and while it sits in the paint gun's reservoir between coats?

I'm almost there!
 

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Okay, some more time in Germany has passed while I've been sourcing and waiting for stuff to arrive... BUT... I think that I'm almost there. I now have my Wagner, AAA, and 3M respirator. And I've checked that the local store can tint the base paint for me. If I can convince my supervisor to help me cut and build the frame this weekend, I should have my BW screen up in just a few days!
:T

One loose end for me now are whether or not I attempt to apply a primer first to my 3 mm white-on-one-side hardwood. When I look for primer in the hardware store I only see 10 L tubs, which would be overkill. If I do find a smaller can and decide to prime first, would I have to wait a few days for the paint to cure before I spray BW over it, or would I be able to do it all on the same day? How about bugs/flies? The more painting I do, the more likely it is that they'll get on the screen - is it easy enough just to pick them out?
It's interesting that you can't find small amounts of white primer. :scratchhead: Here in the States there are so many brands and variations of primer they have there own section in the paint department. If I couldn't get primer for a reasonable cost, I think I would use a flat white paint of the same brand that is used for the base for your BW. Does that make sense?

I would spray the primer or white paint on one day and then spray the BW the next, but if conditions forced doing otherwise I guess you could paint it all in one day - but it would be a long day and I wouldn't recommend it unless absolutely necessary.

As for bugs/debris getting in the paint during spraying - my approach is to have a pair of small tweezers so I can remove such before the paint dries. If some are missed until after the coat has dried to the touch and it's time to spray again, I have found that many times small bits of whatever can be rubbed off with a nitrile-gloved finger (latex gloves would probably work too). If the debris has been painted over even once it pretty much becomes part of the screen. :)

My Dad thought that if I rub the laminate with steel wool or sandpaper it might hold the paint a little bit better. Is that a common thing to try?
While that idea is sound since it creates little "toe-holds" for the paint to stick to. it is very hard to do and maintain an even gloss over the laminate. This wouldn't matter too much with a paint as dense as BW, but the more translucent mixes may be affected by the gloss difference of the undercoat finish is it isn't sanded or wooled to an even gloss. I forget what you are thinking of applying to the laminate side.

I still have a couple of naive questions as well. I'm been looking for these squirrel cage paint mixers but haven't see one so far... if I can't find one can I just mix it by hand? Bubbles shouldn't be a problem, I suppose, since I'm spraying...
I guess you might have to do what you have to do... , but I would recommend getting some kind of stirring attachment for a drill if possible, or even make your own out of a thin wire rod. I've used a handmade one that looked a lot like a question mark ( ? ), and while it worked better than stirring by hand with a stick, it wasn't as good as the squirrel-cage stirrer - those things are magic.

No, bubbles in the mix have never been a problem for me when spraying.

Do you have to be careful about the paint drying/evaporating while you mix it, and while it sits in the paint gun's reservoir between coats?
I've never had a problem with that. The Wagner is a sealed cup so I wouldn't think evaporation would be a problem if spraying the screen at one setting; although I have read that you should clean the tip of paint even between coats. Bang on Mech's door until you wake him up! He is the one that has used a Wager. :bigsmile:

I'm almost there!
Cool! :T

Please take photos if possible. ;)
 

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It's now Black Widow Eve... I have my paint and other supplies, my Dexter style kill/spray-paint room in my landlord's garage, and I tried out the Wagner today with some of my excess base paint. Fun! Even my girlfriend liked it.

So I'm checking in for some last minute questions before I do the dance on Tuesday or Wednesday -

I don't have a squirrel-cage drill mixer, but I did find one that's like a propeller and seems to work more or less ok. What surprised me though was how THICK my base paint is. (None out of 4 stores could tint brand that I wanted, but what I have seems to be the right BB color). I need to add almost equal amounts of water before it would go through the viscosity cup in less than 45 seconds. Initially I tried to strain it into a cup through a nylon stocking and it just sat on top! Has this thickness been the case with any of the brands used so far for BW? I suppose that the AAA will dilute it a little bit but I'm not sure if 30% will be sufficient. It makes me a little concerned that a 4:1 ratio would have too much BB pigment. I should also ask - should the final thinned mix be strained into the Wagner paint cup?

Finally re: the spraying. When spraying it seems that you can either : 1/ Have a sparse layer such that that not all the surface is covered. i.e. you see the individual droplets. 2/ Spray just enough that neighbouring paint droplets join, and the surface has a wet look. 3/ Spray so much that all the paint forms a wet (saggy?) layer. Is it safest to do thin layers as in 1/ and simply do more coats? I don't trust my judge enough to try and push the limit of how much paint can be applied before sagging occurs. It seems then that it might be favorable to have the gun set to less than full volume so that there's no rush as you spray back and forth.

The only other question that I can think to ask is whether people get through more than the 26 oz/800 ml paint cup when they paint a screen. I was thinking of mixing just one of my 4 oz AAA bottles, since the whole mix with thinning would be something like 26 oz then. Maybe I'd be risking sputtering as the mixture runs out though...

Thanks so much for all the advice Harpmaker. In a place where you can't yet speak the language and shops are always closed (the 2 hardware stores near me close at 1 pm on Saturdays and don't reopen until Monday!), it's easy to get discouraged. The support on this forum is definitely pulling me through.
 

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Hi Sam,

One of the problems you are facing is that you aren't using the same base paints the BW developers used. That is a problem that cuts both ways since it's hard to recommend an exact amount of water to dilute with either.

Even here in the States different house paint brands have different thicknesses out of the can. Some are almost like a thick cream while others are almost gels!

If I were in your situation I think I would thin the base paint with water until it thins enough to mix well with the AAA, but NOT to the point it will spray though the Wagner. I understand your question about using the base paint full-strength or thinning it before measuring it, and it's a coin-toss for me. The thing is that the water will evaporate and doesn't stay a permanent part of the mix after spraying so thinning the paint before measuring it will decrease the actual amount of base used and probably affect the color of the mix.

After thinking about it awhile I think I would measure out the base paint full-strength and then dilute with water before mixing in the AAA, but it really is a coin-toss. :dontknow: And no, I don't recall anyone else having to deal with paint that thick.

When it comes to spraying the final mix, dilute it either using the viscosity cup as a guide or your experience spraying. I will say that it is better to err on the side of being too thin rather than too thick.

The safest thing to do is to strain the mix before spraying it. Having said that, I will have to admit that I don't strain my mixes; but I also have paid the price for not doing so. It takes a pretty big piece of debris to plug up my spray gun, but I'm not sure about the Wagner. The bad news is that any debris in my paint gets thrown onto whatever I'm painting!

When spraying, it is also best to err on the side of too thin a coat since any runs can cause a LOT of grief. I usually find that when I spray the paint goes on the way you describe in the #1 scenario. What I do is if I think the screen will take it without the #3 scenario occurring is immediately spray another coat on. In this situation I call these "coats" passes and it can take two or three passes before I think any more applied paint might be in danger of causing runs.

Another thing I have had happen is if I dilute the mix a bit too much and I spray it on too thick it will develop small areas (1/16 " to 1/4" in diameter) where the paint doesn't run, but also doesn't stick well to the substrate and pulls back because of surface tension. It looks weird to see these little "holes" forming on the screen after you spray. If that ever happens to you don't be overly alarmed; while it isn't good, you don't have to start all over again. I have found that two or three proper coats will cover these so they aren't visible.

If is safest to do more thinner layers. I find that my coats of paint usually dry to the touch in 10 to 15 minutes. This might not apply to your base paint though...

Mech will have to answer your questions on the Wagner settings. I'll rattle his cage for you. :bigsmile:

When spraying, I try to put on about 1 fl. oz. of paint per square foot of screen, but when people roll BW sometimes they stop with the first coat if there are no roller marks or other application imperfections to correct and the screen is an even color.

Glad to be of help to you from so far away. :T I'll go yell for Mech now. :D
 

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Sam,

If you intend to spray, you need to get it to the proper viscosity. Adding the water won't hurt anything as it will eventually evaporate. If it has to be 50:50 so be it. You'll just have to do a couple extra coats. The viscosity cup is a good judge of your mix. Get it to <45 seconds. :T
 
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