Cabinet construction techniques

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muth
Posts: 6
Joined: Sun Mar 09, 2014 12:45 am
Location: Santa Cruz, California

Cabinet construction techniques

Post by muth » Sun Mar 09, 2014 2:20 am

I'm new to speaker cabinet construction. I've built some kits using using prebuilt cabinets in the past.

I've decided to try my hand at building my own cabinets. I'm using the Meniscus Overnight Sensation kit for my first build.

I'm using 1/2 in. MDF for the top, bottom an sides. The baffles are two 1/2 in. MDF pieces glued together for a total thickness of 1 in.

My first question for those of you who build cabinets is: what joints do you typically use when building your cabinets? I'm using "glue and screw" butt joints, but I've I've seen some drawings that show miter joints.

What really works?

johnnyrichards
Posts: 55
Joined: Fri Mar 08, 2013 10:11 am

Re: Cabinet construction techniques

Post by johnnyrichards » Mon Mar 10, 2014 5:22 pm

The glue is going to be stronger than the material it is stuck to so from a strength perspective, it doesn't matter too much either way.

Butt joints are the easiest to build, but are surprisingly difficult to get square - and if you plan on painting them, butt joints leave a lot more prep work behind.

bullittstang
Posts: 8
Joined: Wed Feb 26, 2014 6:37 pm

Re: Cabinet construction techniques

Post by bullittstang » Mon Mar 10, 2014 5:32 pm

First off, I don't think you need to make the front baffle 1" think, I used .50" and it is plenty, mainly because it isn't a very tall or wide speaker. If you are using a 1" baffle, be sure and cut some relief/round-overs on the back of the baffle, so the woofer can breathe.

I typically use butt-joints, with my only real design choice being the front and top over lap the other panels. So make the overall cabinet depth 0.50" short (1" in you case) to accommodate a full front baffle then make the sides and back 0.50" shorter, so the top panel overlaps those three (I just make the bottom fit inside the sides and back, so it is the smallest panel you cut). IMO doing it this way makes it easier hide the seems when you are finishing/painting, since people will most often be looking at the front baffle and top of the speaker.

Sealing MDF, I have seen 2-3 different processes. Some use Fiberglass resin, I have had a bad experience trying that one. I use the wood-glue/water method, or wood filler and auto body finishing putty with a razor blade methods most often.

If you are willing to trade some finishing time for assembly time, no need to use miters. They are quite difficult, unless you have the right tools and lots of clamps. Figuring miters also requires more patience and slightly more complex math. Another bonus to using butt-joints, if you cut one panel too short, just use it for the bottom panel.

muth
Posts: 6
Joined: Sun Mar 09, 2014 12:45 am
Location: Santa Cruz, California

Re: Cabinet construction techniques

Post by muth » Mon Mar 10, 2014 11:01 pm

johnnyrichards wrote:Butt joints are the easiest to build, but are surprisingly difficult to get square - and if you plan on painting them, butt joints leave a lot more prep work behind.
Difficult to get square - check
More prep work - check

Are you hiding in my garage watching me or something?

muth
Posts: 6
Joined: Sun Mar 09, 2014 12:45 am
Location: Santa Cruz, California

Re: Cabinet construction techniques

Post by muth » Mon Mar 10, 2014 11:13 pm

bullittstang wrote:First off, I don't think you need to make the front baffle 1" think, I used .50" and it is plenty, mainly because it isn't a very tall or wide speaker. If you are using a 1" baffle, be sure and cut some relief/round-overs on the back of the baffle, so the woofer can breathe.
Yeah, I know 1" baffles are overkill for the OS, but I'm also using this build to practice for bigger, more ambitious builds so I'm OK with going a bit overboard on this one. And yes, I am planning to chamfer the back of the baffle woofer hole.
I typically use butt-joints, with my only real design choice being the front and top over lap the other panels. So make the overall cabinet depth 0.50" short (1" in you case) to accommodate a full front baffle then make the sides and back 0.50" shorter, so the top panel overlaps those three (I just make the bottom fit inside the sides and back, so it is the smallest panel you cut). IMO doing it this way makes it easier hide the seems when you are finishing/painting, since people will most often be looking at the front baffle and top of the speaker.

Sealing MDF, I have seen 2-3 different processes. Some use Fiberglass resin, I have had a bad experience trying that one. I use the wood-glue/water method, or wood filler and auto body finishing putty with a razor blade methods most often.

If you are willing to trade some finishing time for assembly time, no need to use miters. They are quite difficult, unless you have the right tools and lots of clamps. Figuring miters also requires more patience and slightly more complex math. Another bonus to using butt-joints, if you cut one panel too short, just use it for the bottom panel.
Thanks for the tips.

I do have another question:

For those of you who do use miter joints, what sort of tooling, jigs, fixture, etc. do you use to cut long miters?

muth
Posts: 6
Joined: Sun Mar 09, 2014 12:45 am
Location: Santa Cruz, California

Re: Cabinet construction techniques

Post by muth » Mon Mar 10, 2014 11:27 pm

I suppose I owe you guys some pics:

First, the cabinets ready for cutting the baffles:

Image

And the guts:

Image

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