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FI15INCH
07-02-2008, 12:27 PM
when making my box, yes i pre drill, but its splitting on me regardless any type of screws i should be using?

stuckinok
07-02-2008, 12:30 PM
your pre-drill hole is too small

duece212
07-02-2008, 12:31 PM
your pre-drill hole is too small

Or not deep enough, or your over tightening

jco1385
07-02-2008, 12:31 PM
fine drywall screws. i used a pneumatic stapler and titebond 3. worked perfectly.

drill the hole to the same size as the shank of the screw so that only the threads are cutting into the wood. it shouldn't split that way

FI15INCH
07-02-2008, 12:32 PM
your pre-drill hole is too small

Ok thanks, and is drywall screws ok? or should i run up to home depot and get something better?

jdawg
07-02-2008, 12:33 PM
buy an air brad nailer

jdawg
07-02-2008, 12:33 PM
drywall screws are fine 1 1/2 fine thread

jco1385
07-02-2008, 12:33 PM
buy an air brad nailer

x a mille. saves a ton of time and effort

stuckinok
07-02-2008, 12:34 PM
Or not deep enough, or your over tightening

Thats what she said :crap:

FI15INCH
07-02-2008, 12:34 PM
thanks for the fast replies!

Curt

duece212
07-02-2008, 12:40 PM
Thats what she said :crap:

it happens :laugh:

Ed Lester
07-02-2008, 01:01 PM
And what thickness MDF?
I use coarse thread drywalls because I have had fine threads pull out on SPL boxes.
The quality of screws from Lowes is much higher than Home Depot. I have gotten boxes of screws from Home Depot in which the screws had defects such ad no threads, or the philips grooves were not there or filled in, and alot of crooked screws.

mlstrass
07-02-2008, 01:05 PM
Glue holds the box together, not the screws, so fine or course shouldn't matter. Just needs to pull the panels together until the glue dries...

I've torn apart numerous old boxes and the glue joint always holds and the MDF peels away. Other then Gorilla glue which ****** and didn't bond well at all...

jco1385
07-02-2008, 01:07 PM
Glue holds the box together, not the screws, so fine or course shouldn't matter. Just needs to pull the panels together until the glue dries...

I've torn apart numerous old boxes and the glue joint always holds and the MDF peels away. Other then Gorilla glue which ****** and didn't bond well at all...

this is why i chose air stapler. and it looks cleaner IMO

bjfish11
07-02-2008, 01:10 PM
this is why i chose air stapler. and it looks cleaner IMO

Clamping pressure of screws> brads :fyi:

jco1385
07-02-2008, 01:11 PM
pressure of clamps > pressure of screw. or at least =

bjfish11
07-02-2008, 01:11 PM
pressure of clamps > pressure of screw. or at least =

no one was comparing clamps and screws ;)

jco1385
07-02-2008, 01:13 PM
;)

i had it clamped up pert nice

.::DuD3::.
07-02-2008, 01:23 PM
Thats what she said :crap:

I was just about to say that :crap:

kovemaster559
07-02-2008, 01:25 PM
you dont need screws. use glue and clamp.maybe brads if you feel you should

JL Audio
07-02-2008, 01:25 PM
Try some spax.. their self countersinking screws, i've seen someone on here use them in a build but I never could find any myself.

CRXBMPN
07-02-2008, 01:29 PM
i use coarse thread 1 5/8" screws, the fine threads would strip the wood even when the clutch on my Ryobi drill was set to 3. Liquid Nails for the bond.

stuckinok
07-02-2008, 01:30 PM
I dont care what anyone says I have found in my own box building that I need screws. Not alot but 1 every six inches. I dont have all day to sit there and let one side dry until I move on to the next. I would like for someone to show me proof that a box without screws is better them a properly built box with screws and I mean real proof not he say she say BS.

jco1385
07-02-2008, 03:10 PM
I dont care what anyone says I have found in my own box building that I need screws. Not alot but 1 every six inches. I dont have all day to sit there and let one side dry until I move on to the next. I would like for someone to show me proof that a box without screws is better them a properly built box with screws and I mean real proof not he say she say BS.

no one ever said any was better than any other...:confused:

SPY
07-02-2008, 05:45 PM
1-1/4" coarse thread drywall screws and a 3/32 countersink bit.

coarse thread seems to put pressure on the joints better than fine thread IMO...

Ed Lester
07-02-2008, 06:04 PM
at just over 160dB on the dash and 175 in the box, I was measuring over 800 lbs of pressure on my back wall.
I used some of the strongest glues available and they will never hold without screws. Glue, screws, and some fiberglass still pulled apart once in a while.
So I developed techniquies in construction to hold it stronger.
In my experience. Screws hold the box together and the glue merely seals and reinforces.

edzy
07-02-2008, 10:43 PM
Ive always used glue and finish nailer. Never had problems. However, in Eds Case, a box designed to hit 160, yes, you will need as much bond as possible. lastly, most ppl who are here looking for box advice are not 160 ppl. Just looking for a decent box.

And to the op, are you countersinking the heads? Ive always used 1/8 inch bit and course 1/58 drywall screws, before I got the nailer. Also, dont put screws less then 2" from any end.

Vermithrax
07-03-2008, 12:29 AM
Another theory is regardless of the fastener type or clamps involved, too much clamping pressure merely squeezes the majority of the glue out of the joint rendering the glue joint weak, therefore the fasteners would be needed to hold the joint together.

I've done screws, brads and clamps only. The screw method is the most costly and moderate time-wise, brads are the fastest and in the middle cost-wise, clamping is the cheapest but takes the longest, but if you have enough clamps you can assemble the whole box and let it dry as a unit, given it isn't an extremely complicated design.

IgnoreMe
07-03-2008, 01:48 AM
i find good luck with either 1/8th" bits, but i have split it with that.

generally most people find best luck with 5/32th bits.