Glue Holds Bbox Together, Not Screws?

[stevew007 10+ year member]

if you are to lazy or think glue is enough you are a HACK thats all there is too it. It just shows the lack of pride in your work.I like when people tell me "thats overkill"

 

[Boomsday 10+ year member]

You dont need screws, unless your an inferior box builder //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[tommyk90 5,000+ posts]

Okay.. a question for both of you two ^^. Whats your opinion if I CANT get screws in? Im building a box in my trunk within the next month or 2 and I can use brad nails everywhere except to put the last piece of the box on.. which will probably be the top. I will not have space to get a brad nailer or any other tool in there.. what do I do then?

I saw that video.. and at the time thought "Hmm, good thing my box is screwed and glued together"

But honestly.. think about it. IMO I doubt a box really sees ANY lateral force like the test he had setup. IMO a better test would be to make an airtight box with glue, glue + nails and glue + screws.. and then to somehow pressurize it with air. You would be making a bomb.. but just curious at what point something would fail.

Can you do L-bracket strips on the inside?

Or as others posted, lots of bracing strips and fiberglass. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[NT_Hardcore 10+ year member]

why cant you screw the top down from the inside?

 

[ladybridgeport]

Glue together, brace panels, then fiberglass all seams, 6-8 layers or so. This will be stronger than anything listed so far. And a coat of resin will help maintain tuning. Don't forget MDF is porous.
want more strength? Multiple layers with overlapping seams and glass that.

I don't know about using resin. MDF is glued together. When I cut the wood, I notice it has soft spots from less glue. If you apply resin, it will soak in a layer or two then release the glue and the first couple layers of MDF will separate when your banging. Would glue, screws, and triangle braces, followed by deadskin spray liquid dynamat type material be best? Another installer used the liquid spray deadener and gained 3 dB from the enclosure.

 

[Kangaroux 5,000+ posts]

I don't know about using resin. MDF is glued together. When I cut the wood, I notice it has soft spots from less glue. If you apply resin, it will soak in a layer or two then release the glue and the first couple layers of MDF will separate when your banging. Would glue, screws, and triangle braces, followed by deadskin spray liquid dynamat type material be best? Another installer used the liquid spray deadener and gained 3 dB from the enclosure.

Could have been a poorly sealed box

 

[KTMrida4life 10+ year member]

why cant you screw the top down from the inside?

How would that work?

The problem is that obviously, in the end..you have to end up with a sealed box (minus the port) which means that one piece has to go on last.. more than likely the top. When that piece goes on, you can no longer get inside the box.. Subs wont even be removable. They will be screwed in and wired before hand.

 

[brodeisel 10+ year member]

Yeah, I had emailed both of them immediately, but the memphis is sale pending, and the RE's I haven't heard back on. I'm still searching though! Thanks for the advice on the boss, and I will keep on looking!

you fail so hard that it is not even worth a face palm

 

[keep_hope_alive Premium Member]

I think what we learned here is that people have their own preferences on the materials they want to use. In the end, the methods will vary based on the expected outcome and end use. For SPL competition, we should all agree that too much isn't enough, and overkill is a minimum.

For the other 98% - take your pick.

 

[keep_hope_alive Premium Member]

I don't know about using resin. MDF is glued together. When I cut the wood, I notice it has soft spots from less glue. If you apply resin, it will soak in a layer or two then release the glue and the first couple layers of MDF will separate when your banging. Would glue, screws, and triangle braces, followed by deadskin spray liquid dynamat type material be best? Another installer used the liquid spray deadener and gained 3 dB from the enclosure.

Raw MDF is not glued. All engineered woods use a formeldahyde based resin to bond the fibers. The type of fibers used, the combination of heat/pressure, and the fiber orientation vary based on which engineered wood you have. MDF, HDF, particle board, OSB, plywood, etc. all use the cheap formeldahyde resin. This is why burning it is a bad idea. Yes, I researched engineered wood one day... I needed to know what kind could be used as a mock-up in an air handling unit... The verdict was none. They also off-gas formeldahyde when new.

Adding resin to MDF is fine and strengthens the fiber bond while making it water resistant, glassing inside and outside the seam takes it to another level of strength. Try it for yourself. Try two boards glued and screwed and two boards glued and glassed with 6-8 layers of 3/4oz. I've met people on both sides of the fence - screws vs glass. Both can work well.

 

[wenn_du_weinst 10+ year member]

you mean a thread on this subject that has the correct answers? I constantly got flamed for saying the same thing as tommy about the joint being the only strong point.

 

[Buck 5,000+ posts]

i use loctite pl premium advanced.
ive had to change the baffle on one of my boxes and had to cut the **** thing off with a jig saw. tried to knock it off with a hammer and the mdf just split.

I use this a lot doing aeros and bracing. That's some messy stuff and it stains the skin so badly //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

 

[ladybridgeport]

At the shop, I'm going to screw and glue two boards together. I'll do that twice, one will not have resin, the other will have resin. After curing, I'll destroy both to see which holds up better.

 

[Phoenix Risen 10+ year member]

I use this a lot doing aeros and bracing. That's some messy stuff and it stains the skin so badly //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

i know that very well

any time i use it i wear gloves of some sort, its just way to hard to get off.

 

[The_Grimy_One 10+ year member]

Fiberlgass and Angle iron outside seams? srs answer
Add interior edge braces to substantially increase surface area for gluing.

Can we get pics of said box methods? //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif