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Discussion Starter #1
I've been adviced to use birch for subwoofer enclosures. I just need to hear arguements for/against using either birch or MDF.

Does Birch splinter easily? Is it harder to work with?
 

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In theory the MDF might be more dense and offer better performance. But I don't know if it would make a noticeable difference in the real world. The Birch might last longer and resist humidity better. I don't have a problem working with either.
 

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The biggest issue is moisture. Birch will stand up to humid climates MUCH better than MDF. As far as rigidity and the like, as long as you brace properly it will be negligible.

Birch=Humid Climates/Marine
MDF=Everything else
 

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The good thing about Birch is that it can be stained and clear coated for that pro look.
Nice for house speakers also.
 

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I just built mine with Birch from what I understand it is a bit lighter but the only thing I hate is the splintering. No matter what we were doing it peeled and splintered.

(Bit unnerving)

If I had to do it over again likely just 3/4 mdf (SQ build) but its working
 

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birch is lighter, stiffer, and holds up to abuse and moisture better. It also holds screws better.
Mdf is denser and cheaper.
 

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Discussion Starter #9
Oh, and as long as your saw is sharp and you take your time you don't have to worry about splinters with birch.
I just built mine with Birch from what I understand it is a bit lighter but the only thing I hate is the splintering. No matter what we were doing it peeled and splintered.

(Bit unnerving)

If I had to do it over again likely just 3/4 mdf (SQ build) but its working
I guess for me its going to be trial and error. Thanks for your replies so far. I'll try and look for good quality stuff ... which at the moment Marine bich seems to get a lot of mention.
 

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I always used MDF for building installs and other audio-related projects, but now in Xenia's car, I'm using 18mm Meranti-ply, I think it's 9 ply's.

MDF is easier to saw and sand into shape without splintering, since it's basically grinded wood mixed with glue, there are no long fibres in it...

With the meranti-ply, every saw-cut is splintered at 1 side, even when using a very fine saw-blade and taking time, so if you want nice sharp 90° cuts, MDF is the way to go.
I chose meranti-ply-wood because of it's strength.
If you take a piece of 8mm MDF, you'll have to use a bit of force, but then it'll break quite easily. Do the same thing with the same thickness of meranti-play, it'll bend a little faster and the top layer will start to crackle, but it'll take longer and more energy to break it completely because of the long fibers that have a different direction in every layer...

The best stuff is the plywood they use to make molds for concrete walls/beams/... That's ordinary plywood with an epoxy-coating on it on both sides. Because of that coating, it's a lot stronger than regular plywood and it doesn't splinter when cutting it!
It is more expensive though...
 

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Discussion Starter #13
I always used MDF for building installs and other audio-related projects, but now in Xenia's car, I'm using 18mm Meranti-ply, I think it's 9 ply's.

MDF is easier to saw and sand into shape without splintering, since it's basically grinded wood mixed with glue, there are no long fibres in it...

With the meranti-ply, every saw-cut is splintered at 1 side, even when using a very fine saw-blade and taking time, so if you want nice sharp 90° cuts, MDF is the way to go.
I chose meranti-ply-wood because of it's strength.
If you take a piece of 8mm MDF, you'll have to use a bit of force, but then it'll break quite easily. Do the same thing with the same thickness of meranti-play, it'll bend a little faster and the top layer will start to crackle, but it'll take longer and more energy to break it completely because of the long fibers that have a different direction in every layer...

The best stuff is the plywood they use to make molds for concrete walls/beams/... That's ordinary plywood with an epoxy-coating on it on both sides. Because of that coating, it's a lot stronger than regular plywood and it doesn't splinter when cutting it!
It is more expensive though...
As a beginner, I wonder if going to a timber merchant and getting them to cut it for me would be the best bet?

The comment given to me was to the effect of: use brich ply because it will show people tht you care about your products and that as a box builder (which i really want to get into) it also show you won't compromise your products and that you're not in it for the money etc, etc, (you get the picture).
 

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If you have a timber merchant that is precise with measurements and cuts, I'd always recommend to let them do most of the cutting. These guys have professional machinery and lots of experience, but sometimes, you have to do something yourself.
For example, where I buy my sheets of wood, they have a great machine and experienced worker to cut rectangular shapes, but they can't do trapediums, triangles, circles... and they can't do a 45° cut, simply because their machine isn't made for this.
Sometimes, wood-shops have a CNC-router available and then they can do anything you want, including angled cuts, perfect round holes...

That comment is (crap of a male cow), a box made of MDF can sound just as good as a box made out of plywood, and it's easier to cut with hobby-equipment.
The only downside of MDF is the strength of it: you have to use at least 1" thick MDF to get the same solidness and toughness as with 3/4" ply, depending on the quality of the plywood and the MDF.

For subwoofer cabinets I always use 30mm (1 1/4") thick MDF, but now in the Saab I decided to use 3/4" meranti-ply to get the same strength out of thinner and lighter material (but it's harder to cut properly) because a Saab 900 classic is known for it's rather weak rear-suspension and I don't want to mess up it's great weight-balance too much.


For a planned home-audio project, I'm planning to use 30mm MDF for the bass-cabinet and 12-15mm plywood for the upper mid+tweeter cabinet to keep the gravity point low, which will increase the stability of the total speaker compared with all-MDF or all-ply.
 

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I have issues with mdf here are my pros and cons.


Mdf cons : its dust is carcinogenic
is like a sponge if it gets wet its ruined
its hard on tools (saws routers)
It has no screw holding strength whatsoever and if you want to use a screw you need to predrill or it swells out making leaky joints or baffles
It doesn't paint consistantly on end grains and faces
It chips off corners when mistakes are made
Brads shoot wildly through it coming out the sides at very slight angles making finishing difficult
It truly has no strength unless its built into a box of some sort

Pros: it routers nice
Some people believe its more dense making a better non resonant enclosure
its usually cheaper than plywood variants

Ply/ birch Cons:
It splinters when cut sometimes
Its more expensive usually

Pros:
Its stronger
The dust is not nearly as unhealthy and doesn't stay floating for weeks in your shop
Tools last longer
It takes screws ( repeatedly without loosing strength or grip)
It takes brads and they go where they are told
Glues great
Paints the same on end grains usually
If you desire to build with screws they can be sunk under the surface and filled over with bonding making it invisible without predrillig

I'm sure there is more




Sent from my GT-P7510 using Tapatalk
 

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you in buffalo new york rexxxlo?and those are all very interesting points.....in the process of making materials decisions for my box build as well id like to see some more comments.i think after reading this i very well may go to birch instead of the planned mdf.im exposed to enough carcinogens and i like strength altho for a single SWR-843D mdf would prob be plenty strong.it is going in a truck tho and may very well see some shockloads and whatnot.....
 

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You can cut most plywood without splintering by scoring it with a utility knife just shy of the cut line. If it's poor quality or it's gotten wet it may splinter and peel no matter what.
IMO, If you're planning to paint it you should avoid exposing any end grain and miter your corners with either plywood or MDF. At the very least put a thin layer of filler on the end grain before you sand it.
 

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I was in your shoes on Friday, but I went with MDF. I was looking for birch wood around my area and the only birch I was able to locate was 9 ply and I wanted 13 ply. Some people on here are using Arauco and have good results from what I have searched, might want to look into that aswell. Goodluck!
 

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For HD applications, I have always used MDF, braced and doubled at the baffle. Someone said earlier that it's wood pieces and glue, not true (they may be thinking of particle or chip-board -- don't use those).

[WIKI=Medium-density fibreboard (MDF) is an engineered wood product formed by breaking down hardwood or softwood residuals into wood fibres, often in a defibrator, combining it with wax and a resin binder, and forming panels by applying high temperature and pressure.[1] MDF is denser than plywood. It is made up of separated fibres, but can be used as a building material similar in application to plywood. It is stronger and much more dense than normal particle board.]

Anyway, there are techniques you can use to make MDF solid as a rock. It paints perfectly. Smooth as hell. Easily routed, etc.

If you DO use plywood, here are a couple tricks.
-When you run plywood across the table saw, always run the "pretty" side up (bad side to table top).
-Run your saw blade all the way up! Contrary to the "one tooth rule", this will significantly reduce edge splintering.
-To further reduce edge splintering, put two layers of good quality masking tape where you about to cut, mark or position your piece, and then cut. When you remove the tape, it'll most likely be very clean.
-I have gone as far as to make a 1-3 diluted Elmer's white glue wash, and paint the edges of the plywood (then let dry for an hour) before sanding. (helps with edge splintering from the sander at hard edges)

This is my home entertainment center that I designed and built last year, it's primarily birch plywood. The large black squares you see on either side of the components are 12" subs...those are encased in MDF, THEN surrounded by the birch for aesthetics.



(Funny, the picture is over a year old, but the TV headline could be current from this morning, huh? lol Some things never change!)

--Radar
 

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Discussion Starter #20
Thnaks for the tips. For the time being as I don't have a workshop, or garage to work from, i'm going to have to get a timber merchant to cut whatever wood I need. Tday I'm going to ask various merchants if they can cut at angles, mostly fror 45's but also for more complex, or tapered cuts.

the cost for me isn't an issue, I'll pay for quality, but when i do get my own tools, I'l practice on MDF then move onto Ply.
 
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