Cracked MDF???

[Enemy5802]

So I'm making a ported 12" subwoofer enclosure. The holes I pre-drilled aren't completely perpendicular so this resulted in a slightly crookit holes.

I pre-drilled, glued countersunk holes, and inserted the screws. Unfortunatly I overtightened them resulting in a little crack. Here is a picture. So I continue building it and just avoud drilling over that area? what do you think?View attachment 26541981

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[NASTY08IMPALA 5,000+ posts]

Mdf ***** even predrilled ..and is heavy and porous.switch to arauco or birch

 

[Enemy5802]

Wish I'd known that before I started building it. Lol. You think I should keep on building it?

 

[bgowdy 5,000+ posts]

Wish I'd known that before I started building it. Lol. You think I should keep on building it?

i mean i would have used birch from the start. but i would put a semi thin layer of liquid nails over it and keep building. i mean it couldnt hurt to go ahead and finish the box and see how it holds up

 

[Serpent710 10+ year member]

put glue, sand smooth, in the end when your done building it woodfiller and sand smooth.

 

[Enemy5802]

Alright. I think I might use wood putty or something. But ill definitely keep building it. Sand until smooth. Got it. Thanks!

 

[Kingstroker 10+ year member]

Turn it so the crack is facing up. Get a good size bottle of thin CA (super) glue, open the crack up a little and saturate it well then clamp it closed and let it set for a couple of days. While you have it clamped squirt some CA glue in the screw hole and put the screw back in. Make sure you put wax paper over it before you clamp it. When you buy the glue make sure it looks watery or it won't soak in. Keep your screw holes 3"-4" from ends.

 

[americannight 10+ year member]

Seal all seams on the inside with liquid nails or silicon. Also do as suggested and sand the top smooth & fill in with putty as needed. It will be fine.

 

[VWBobby 10+ year member]

Wow, some of the posts are ridiculous... Simple repair. Soak the crack with wood glue, TiteBond II or the like. Clamp it with wax paper or aluminum foil between the wood and clamp to prevent sticking. Unclamp the next day. Sand to shape, if needed. Pre-drill your holes and use drywall screws. It shouldn't crack as long as you don't crank them in too tight. The screws are to hold, the wood glue is what BONDS the 2 pieces. CA Glue is for speaker building, not much use in enclosure building.

 

[Kingstroker 10+ year member]

Wow, some of the posts are ridiculous... Simple repair. Soak the crack with wood glue, TiteBond II or the like. Clamp it with wax paper or aluminum foil between the wood and clamp to prevent sticking. Unclamp the next day. Sand to shape, if needed. Pre-drill your holes and use drywall screws. It shouldn't crack as long as you don't crank them in too tight. The screws are to hold, the wood glue is what BONDS the 2 pieces. CA Glue is for speaker building, not much use in enclosure building.

not for enclosure building but excellent for repairs like I've stated. I've had over 20 years experience in all type of woodworking and have been using CA glue before Titebond started making 2 different kinds of CA glue for wood. It seeps into cracks better than the thicker glues. I've also used it on selfbow (bows made from a single piece of wood) repairs.

 

[tomsteve]

when screwing into the end of a piece of MDF. it is best to use straight shank wood screws. less tendancy for the wood to split. measure the diameter of the screw at the bottom of the thread and predrill to that size.before screwing together, support both sides with a clamp will help prevent splitting. SPAX( and others) make a screw just for MDF.check out mcfeeleys or rockler for them.even with all of the precautions i have used to stop splitting, it can still happen, so i dont end screw MDF any more. i ue a pocket hole jig.i havent built any enclosures(yet), but i build a lot of furniture and have come to love my pocket hole jig and havent had end splitting once using it.

 

[Kingstroker 10+ year member]

pocket holes were probably the best invention in furniture building I've ever seen. I'd suggest using a pan head jig, you can order one from woodcrafter.com. You can buy cheaper ones but the drill bits just don't hold up.

 

[fasfocus00 5,000+ posts]

i've only ran into this maybe twice but I do something similar to door jamb repair. take the splintered piece and place some wood glue into the splinter, take a match stick (obviously minus the head) and put it into the hole. clamp the splinter with a c-clamp and foil. let the glue sit for a day than break of the excess and sand smooth. but as stated above by 2 other experience guys, those methods will work just as good as mine if not better.

 

[Enemy5802]

Ill definitely use the method with the c-clamp. Thanks a lot guys! Appreciate it!