Nice work. When I think of "spray bombs", can't help but to think of people who sloppily spray their cars rather than the nice job you did, hah.
Can you tell me how you did it regarding number of coats, recoat times, wet/dry sanding, sanding between what layers?
Just laid down 8 coats of rusto filler primer spray over the sealer. I kind of had it in my mind to...
• wet sand
• light primer coat followed 10 mins later by color coat and dry for 24 hrs
• 3 coats of color and dry for 24 hrs
• wet sand with 320
• 3 coats of color and dry for 24 hrs
• wet sand with 320
• light color coat followed 10 mins by clear coat and dry for 24
• 3 coats of clear and dry for 24 hrs
• wet sand with 320
• 3 coats of clear and dry for 24 hrs
• wet sand with 1000 and fine steel wool
• cure for 7 days
• rotary foam buffer with polish
"you gotta be a lil crazy to stay sane..."
Mine was a little easier. Zinsser shellac saturate the entire box inside and out. Wait a week. 6 coats of mid grade auto primer. Wait two days. 6 consecutive coats of gloss black acrylic enamel(15 minutes between each coat) this stuff dries fast!. Wait 24 hours. Then three coats gloss black acrylic enamel again. Then I put the project on hold for 3 months. Then wet sand 1000 grit twice with palmolive dish soap (few drops). Wait a week and turtle wax polish ( not rubbing compound). be careful with the steel wool that none of the fibers get into the box as they could be drawn into the voice coil later on it could cause a scratchy sound.
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no sanding between any of those 15 coats of primer and paint?
and what if you don't have (by my estimation of your process) 100 days?
and what if you don't have (by my estimation of your process) 100 days?
Oops I did sand after the primer with 400 grit. I don't know about reduced cure times, but the way mine happened , it worked out.
I just didnt see the point of too much sanding. I used SHINOBIWAN'S wisdom in his thread and adjusted to work for myself.
Fortunately I'm not perfect , perfection takes too long in the general sense.
Now if they were to be frequently scrutinized show pieces then I would put the extra 5- 10 percent effort to get there
I just didnt see the point of too much sanding. I used SHINOBIWAN'S wisdom in his thread and adjusted to work for myself.
Fortunately I'm not perfect , perfection takes too long in the general sense.
Now if they were to be frequently scrutinized show pieces then I would put the extra 5- 10 percent effort to get there
Now if I were to do it again I would not use mdf or brad nails or pva glue.
Baltic birch, pocket screwed, mitered joints and maybe cascamite? glue.
Nothing on the outside surface of the box that would later take time to correct.
After all ,whats on the surface is usually just good illusion in the finished product.
Baltic birch, pocket screwed, mitered joints and maybe cascamite? glue.
Nothing on the outside surface of the box that would later take time to correct.
After all ,whats on the surface is usually just good illusion in the finished product.
It depends on the glue. PVA based glues it will show over time. You need a glue that dries solid.
Screws is an acceptable method if you don't have clamps and has an advantage if you are trying to assemble by yourself as alignment can be easier. Wood glue and dust mix is a poor filler for covering the screws though, it will show over time and does not bond brilliantly to either the screwhead or to the paint you put on top of it. Use 2 part mix polyester filler such as Bondo.
I just made 3 speaker enclosures using birch plywood, glue, and butt joints with pocket screws. those cabinets will never come apart. pocket screws with miters are going to be a problem since the screws go in at an angle. they'll pull the joint out of alignment as they are tightened.
BTW My friend used cascamite for his curved walls using flexy MDF and a jig. He really likes it and the added weight the glue has surely will be beneficial to sound. Good stuff.
A simple square dado/rabbet can provide some extra glue surface area and stiffening to the joints - I usually go between 1/3 to 1/2 depth on my enclosures. .
In case there's not sufficient confusion / obfuscation regarding PVA wood glues - let's add a bit more 😉:
Most current yellow carpenter's glues could be broadly classified as crosslinked PVA ( think genetically modified 😀) such as Titebond II or aliphatic resins such as Dural AW2300 (Red label), and do no suffer from drying soft, as is definitely the case with white PVAs (Weldbond, Elmers, Roo Melamine glue, etc) . We use both of the above named yellow wood glues in our commercial shop, and they certainly dry hard enough to be used in vacuum bag fabrications of rigid curved bulkhead panels or speaker enclosures. Normal white glue would definitely not give the same results.
In case there's not sufficient confusion / obfuscation regarding PVA wood glues - let's add a bit more 😉:
Most current yellow carpenter's glues could be broadly classified as crosslinked PVA ( think genetically modified 😀) such as Titebond II or aliphatic resins such as Dural AW2300 (Red label), and do no suffer from drying soft, as is definitely the case with white PVAs (Weldbond, Elmers, Roo Melamine glue, etc) . We use both of the above named yellow wood glues in our commercial shop, and they certainly dry hard enough to be used in vacuum bag fabrications of rigid curved bulkhead panels or speaker enclosures. Normal white glue would definitely not give the same results.
If you mix a little polyester (fiberglass) resin with the bondo so that it is the consistency of a thick milkshake prior to adding the bondo hardener you can use the MEKP hardener that comes with the polyester resin and it is VERY easy to get an accurate and consistent spread and curing of the bondo.
It will also self level and fill small gaps in joints for you.
It will also self level and fill small gaps in joints for you.
Can you elaborate such as when you mean a little and a little more to the process so I at least have a guideline to go by when I try?
The poly resin and mekp hardener, are these things I can get at home depot?
"you gotta be a lil crazy to stay sane..."
I'm a little disappointed with the way my first enclosure seams are showing... I'm slathering the crap out of the joints and seams on the second box I'm working on l. I guess this wouldn't work well for the guys who don't paint but i guess i have that luxury, haha. The seams where I sanded flush to the glue seem to be hiding very well under the paint in the first box. I'd honestly rather do this on at least these builds than figure out how to use bondo better or that fiberglass mixture. Does anyone know of any negatives of this method?
BTW, I'm using gorilla wood glue. I'm guessing that falls under the cross-linked PVA. Seems to take well to the zinsser cover stain/primer/paint. No adherence issues.
Seriously contemplating just getting a giant block of hardwood and just carving it out to hold the driver. Not a bad idea right?
"you gotta be a lil crazy to stay sane..."
BTW, I'm using gorilla wood glue. I'm guessing that falls under the cross-linked PVA. Seems to take well to the zinsser cover stain/primer/paint. No adherence issues.
Seriously contemplating just getting a giant block of hardwood and just carving it out to hold the driver. Not a bad idea right?
"you gotta be a lil crazy to stay sane..."
OK, I assume you know how thick a milkshake is.......
Bondo out of the tub is about the consistency of soft clay.
Mix small amounts.
At this point DON'T add any hardener at all, add just the raw epoxy resin to the bondo.
Keep adding resin until the bondo is about the consistency of a milkshake.
Once you have that milkshake, take a note of the volume of the milkshake and add the appropriate amount of liquid hardener that came with the resin for the volume of milkshake you have.
Too much hardener and it can crack from the heat and shrinkage to little and it will take FOREVER (or never) to cure.
Spread it on, scrape it out with a straight edge, let it cure overnight, block sand it smooth.
Repeat the steps if you need additional coats.
Bondo brand fiberglass resin is available in the paint department of my Home Depot.
The paint department will also have measuring mixing cups to make it easier to know how much hardener to add.
Bondo out of the tub is about the consistency of soft clay.
Mix small amounts.
At this point DON'T add any hardener at all, add just the raw epoxy resin to the bondo.
Keep adding resin until the bondo is about the consistency of a milkshake.
Once you have that milkshake, take a note of the volume of the milkshake and add the appropriate amount of liquid hardener that came with the resin for the volume of milkshake you have.
Too much hardener and it can crack from the heat and shrinkage to little and it will take FOREVER (or never) to cure.
Spread it on, scrape it out with a straight edge, let it cure overnight, block sand it smooth.
Repeat the steps if you need additional coats.
Bondo brand fiberglass resin is available in the paint department of my Home Depot.
The paint department will also have measuring mixing cups to make it easier to know how much hardener to add.
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Hah, I think I asked a stupid question. Pretty much just milkshake and handle it like any two part system. Thanks.
"you gotta be a lil crazy to stay sane..."
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