Best fasteners for high SPL builds

[rickandleli 1]

Just trying to get an idea on what kind of screws are best for putting together a big box that is made of 2 sheets of 3/4 MDF stacked. (1 1/2). What about sealer? i know some people use liquid nails, but have heard other people say no way. just maybe some options on this critical piece of high pressure builds.

[rmzsuzuki89 61]

Corse thread drywall screws work well. And if youre doubling up everywhere, you can stagger the two layers so there is more surface area for the glue to bond. The sides will fit together like stair cases. And about the liquid nails, only use it to seal the inside of the enclosure, not as actual wood glue (I just use silicone caulk on the inside of mine). I would recommend Titebond II or III for glue.

[creatormass 1]

I've always built mine using the liquid nails as a glue between all the pieces, then used the coarse drywall screws to hold everything together. When everything is all dry and cured, I usually end up applying a layer resin to the entire inside of the enclosure, but thats only with the SPL ones.

[shizzzon 461]

i've also heard alternative to resin or addition to resin is to sand over resin, if exists, enamel paint(apply before resin if u still want to use resin), turtle wax + armor all.

Goal - extreme smoothness.

[creatormass 1]

i've also heard alternative to resin or addition to resin is to sand over resin, if exists, enamel paint(apply before resin if u still want to use resin), turtle wax + armor all.

Goal - extreme smoothness.

I've heard of using wax over the resin, but never heard of Armor All. Armor All is used on the interior of the vehicle around here, good for a few 10ths of a db.

[///M5 2,833]

?

Seriously, Liquid Nails to hold an enclosure together? NO. Wood glue ftw. A properly glued joint with tight bond will be stronger than the rest of the box. No screws, no brads, nothing else is required for the joints. Of course that assumes you do it properly, but it is all that is necessary. Liq Nails is terrible for this btw.

[creatormass 1]

?

Seriously, Liquid Nails to hold an enclosure together? NO. Wood glue ftw. A properly glued joint with tight bond will be stronger than the rest of the box. No screws, no brads, nothing else is required for the joints. Of course that assumes you do it properly, but it is all that is necessary. Liq Nails is terrible for this btw.

To each his own. I've built maybe 10 different SPL enclosures using this, and screws and never had any of hem leak. I've used this with several daily boxes too, and still no leaks or any other issues. Liquid nails works fine along with screws, I wouldn't use it on it's own though, and having plenty of pressure applied to each of the panels is a must whether your using wood glue or liquid nails. You'd need to have a few of those really long wood clamps to do it right. The box I have in my ride right now was done with wood glue, no nails, screws or anything else and it's very strong.

[///M5 2,833]

Wood glue is significantly better at bonding mdf than Liquid Nails. Test the two in the same conditions and you won't use LN again.

[bassahaulic 155]

Wood glue is significantly better at bonding mdf than Liquid Nails. Test the two in the same conditions and you won't use LN again.

x2

Once the wood glue dries, it is the main thing holding the box together. You could, in theory, take all the screws out the box after the glue dries and it should stay together. I just can't see liquid nail doing this.

[tommyk90 3]

I've pulled panels clean off that were "glued" together with liquid nails.

Titebond forever.

But if you are looking for a caulk type glue so it holds it's shape and doesn't drip everywhere, check out PL construction adhesive. Stuff is SUPER strong.

[Adrian_D 520]

Wood glue is significantly better at bonding mdf than Liquid Nails. Test the two in the same conditions and you won't use LN again.

x2

Once the wood glue dries, it is the main thing holding the box together. You could, in theory, take all the screws out the box after the glue dries and it should stay together. I just can't see liquid nail doing this.

x eleventy billion.

Wood glue joint, mdf sheared before the glue broke. Took out all the screws when taking the box apart and hammered on it 30 minutes to take it apart. I never could cleanly separate 2 panels glued with woodglue.

On a well cut box you will only need a small bead of glue on the seams to seal everything. If there are gaps, best to fix them with wood glue mixed with sawdust. You can hardly sand that mix after it hardens, it's beyond tough.

[tommyk90 3]

I've used the old sawdust and glue mix many times.

No table saw FTL.

[rushnrun 14]

wood glue FTW!

tommy I've been there... fix the crack via dust and glue

[Julian 641]

i've heard that gorilla glue is pretty tough stuff, haven't experienced it but thought i might throw that into the proverbial swimming pool of glues

[bassahaulic 155]

i've heard that gorilla glue is pretty tough stuff, haven't experienced it but thought i might throw that into the proverbial swimming pool of glues

It's tough, but it expands ALOT and requires you to get the stuff your gluing wet. MDF + Water = Failure.

[djphilly 11]

TIGHTBOND!!!

These new smileys are so funny to me. been trying them out since they became available

[bassahaulic 155]

TIGHTBOND!!!

These new smileys are so funny to me. been trying them out since they became available

Your newer then they are. Just we when switched boards they weren't available at first. It all the old ones we had.

[TechSys 3]

Liquid nails doesn't really "bond" the wood together. Yes it may hold it, but not bond it. Wood glue will do a lot better at bonding the pieces.

Gorilla glue is good, but I would not want to use it on MDF. To get the best result of Gorilla Glue, you have to dampen both joining pieces of wood with water. As Gorilla Glue starts to cure, it'll expand, much like expanding foam (no where near as much though).

I use Titebond I, II, or III. Depends on which one is more available at the time. I have also use tile adhesive for layering 2 pieces of MDF on top of each other. My current wall is done that way. 2 layers of 3/4" MDF all the way around with tile adhesive between them. Works great.

Screws and/or brad nails are only to hold the wood tight together until the glue dries. The weakest point of the enclosures will be where those screws are. At least that's what I believe.

[wof131s 10]

If the glue holds the wood together tight, why wouldnt leaving the screws in be even stronger?

Edited November 24, 2009 by wof131s

[jcarter1885 995]

If the glue holds the wood together tight, why wouldnt leaving the screws in be even stronger?

The screws or nails has no way of been as strong as the glue that is holding it together, there are just there to keep the enclosure together while it dries. Screws eventually come loose over time if Im not mistaking.

[bigrank916 72]

Sawdust and wood glue huh? I'll try that next time.

[ludachris5150 0]

Sawdust and wood glue huh? I'll try that next time.

Im pry jus gunna go with the titebond... But what about the liquid nails thats actually for wood? Says wood right on the tube?

[Duran 387]

Use epoxy, always.

[Argent Audio 54]

A wood glue like titebond actually fuses with the wood on a molecular level as liquid nails does not...

If you really want the best joint possible use the Titebond Molding and Trim Glue, it is designed for porous materials like MDF and Melamine...

In terms on bonding 2 pieces of 3/4 MDF on top of each other the 3M Spray Adhesive works wonders. This is the only stuff that hospitals allow when it comes to bonding agents...

http://solutions.3m.com/wps/portal/3M/en_US/Manufacturing/Industry/Product-Catalog/Online-Catalog/?PC_7_RJH9U5230GE3E02LECFTDQGLE0_nid=ZHLK56LKGWbe42G7LG3SVFgl

[Kanaworm$ 292]

A wood glue like titebond actually fuses with the wood on a molecular level as liquid nails does not...

If you really want the best joint possible use the Titebond Molding and Trim Glue, it is designed for porous materials like MDF and Melamine...

In terms on bonding 2 pieces of 3/4 MDF on top of each other the 3M Spray Adhesive works wonders. This is the only stuff that hospitals allow when it comes to bonding agents...

http://solutions.3m....Wbe42G7LG3SVFgl

I am going to give this a try.