finish option for OSB

[gychang]

I plan to try OSB instead of plywood to build a good sized speaker. I would think the usual stain is not ideal.

Is the paint a reasonable option? (plan on latex with a roller?), will it cover reasonably well? (will it get into the cracks?). Also considering laminate as cover on the visible surface.

any suggestions will be appreaciate.

gychang
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[Tom Slick]

you can paint it but it will look like painted OSB, not smooth at all.


Side note, waaay OT:

do you have a sister that lives in SLO?

[jonmulzer]

OSB is not very rigid. Your box will flex quite a bit and resonate. What about using MDF? If you are looking for cheap, MDF fits the bill and is also perfect for building speaker enclosures and takes paint very well.

[poolhound]

I would second MDF as a material. It is stable, easy to work (not chips like OSB) and takes paint well. As it is uniformally dense I would think it has better characteristics for making a speaker cab. If you are going to paint naked MDF it helps to put a sealer coat on first.

OSB is not flat so laminating could still leave voids. If you were going to the trouble of laminating using pre laminated MDF would be much easier. You can also get good quality veneered MDF that would have the same structural advantages and look great although a bit more pricy.

[LCHIEN]

OSB is not very rigid. Your box will flex quite a bit and resonate. What about using MDF? If you are looking for cheap, MDF fits the bill and is also perfect for building speaker enclosures and takes paint very well.

all very good points. Why OSB?

[gychang]

OSB is not very rigid. Your box will flex quite a bit and resonate. What about using MDF? If you are looking for cheap, MDF fits the bill and is also perfect for building speaker enclosures and takes paint very well.

I will line the OSB with hardibacker cement board I have laying around. Want to avoid MDF with health issues etc.

gychang

[poolhound]

I will line the OSB with hardibacker cement board I have laying around. Want to avoid MDF with health issues etc.

gychang

Health issues with the finished product or just cutting MDF? If you are just cutting enough MDF for a couple of speakers, use good DC and wear a face mask you will have no issues. I am no doctor but the dust and mess from cutting cement board would surely be as bad.

Also OSB backed by cement board will make for a very strange construction and with these two materials layered on each other I would think the cabinet will be prone to lots of vibration that would affect the sound quality.

[gychang]

I am no doctor but the dust and mess from cutting cement board would surely be as bad.

usually I cut the board with the utility knife, therefore no dust. Sounds like OSB may not work out...

gychang

[jonmulzer]

USe MDF. Your plan is likely to cause for a really poor sounding box. If it is purely health concerns that keep you from using MDF, cut it outside with a box fan blowing the cutting dust away from you and wear a cheap dust mask. I really think people worry about things like this way too much most of the time.

[Bigbit]

I'm not sure why the OP thinks that OSB poses a lower health risk than MDF. Both usually use very similar thermosetting resins as a binder - usually a Phenol Formaldehyde or the like. I would not want to breathe in dust from either.

[JoeyGee]

Just have the Big Box cut down the MDF for you. They will tell you they will not guarantee final dimensions, but they have always been fine for me.

[dbhost]

Use MDF if you want a decent sounding speaker cab. I am not 100% sure why you want to do finish per se on a speaker cab instead of something like carpet. I am assuming then this must be for a loudspeaker and not a subwoofer or the like for an automotive install...

As far as the dust goes... Use the dust control your saw SHOULD have... If you are running a BT/21829/BTS then hook it up to a shop vac with a HEPA filter...

And just in case, make sure you are using a good quality dust mask, and cut outside!

Safety first. If you use your head when cutting the stuff, it is perfectly safe...

[knotley]

I have made quite a few speakers and subwoofers and have read a lot about building them. I also would strongly suggest not using OSB. I use MDF cut at the BORG and then acoustic sealant inside and paint flat black. Looks fine. The only thing is that the BORG will not cut the speaker hole. You must do that yourself. I do it outside with a mask.

[JimD]

My subwoofer is in a OSB cabinet. It resides between the floor joists so appearance was not an issue. I have painted OSB, however, it is what the walls and ceiling of my shop are made of. I also used it on a porch roof. For indoor use, I skim coat it with drywall compound. For exterior, I used bondo. With these fillers, the surface is reasonably smooth but still looks like painted OSB. You could put laminate on it, however, just fine. You could also cover it with stick on veneer but I think the OSB would show through. 1/4 plywood could also be used over the OSB.

OSB is stiffer and stronger than MDF. MDF is denser, however. OSB is closer to plywood in strength. MDF is about the same strength as particle board. I do not think MDF is definitely better for speakers than other sheet goods, I think it gets used because of it's relatively high density and it's relatively low cost. I usually use plywood.

Jim

[cgallery]

+1 what JimD says.

MDF is great for building speakers. But building from other materials is not unheard of, and great results can be had.

I've never used OSB for building speakers. But my recent experiements with it for building some shop stuff wasn't that great. The piece I got at HD warped. It almost seems like the smooth side has some sort of finish on it to provide a little bit of water protection. The rough side has nothing on it. I think this imbalance allows for the rough side to absorb moisture.

OSB is cheaper than MDF at BORGS, though.