stud drilling caveats

[skamath]

hi,
i am installing a row of melamine particle board cabinets and i am revisting the size of the 3" screws i am using to install the cabinet to the wall.

the cabinets that i built has 1" back where the cabinets are installed. basically 1/4" back and 3/4" nail board. that leaves 2" of which 1/2" inch is for the drywall and the rest (at least by my earlier assumption) would go into the stud.

well turns out i have a 1/2" plywood sheet behind the drywall, so the screw is only 1" into the stud. i thought this might be still okay.

however i recently realized that in some places there is a small gap (< 1/8") gap between the drywall, plywood sheets and the stud. probably this gap is not all over, but i saw it in at least one place.

so now my question is if i should start using 3.5" screw. or should i use a even larger screw? i guess my question is what are the disadvantages of using a too long a screw. is there a danger that i might hit a pipe or a electrical line? i was initially thinking it is safest not to go more than 1-1/4" deeper in the stud. (assuming a center hole of 1" for wires and such.)

any comments? anybody know of articles/books on this topic?

thanks in advance!

[woodturner]

is there a danger that i might hit a pipe or a electrical line? i was initially thinking it is safest not to go more than 1-1/4" deeper in the stud. (assuming a center hole of 1" for wires and such.)

Those are reasonable assumptions. For wiring, there should be metal plate on the front of the stud over the hole, so that one cannot easily drill into a wire. However, those are often left off.

Coincidentally, I was at the box store looking at anchors yesterday. They have a type of anchor specifically made for mounting kitchen cabinets. Might be a good option for you, rather than a longer screw.

My concern with the screws would be finding suitable screws that are long enough without too great an increase in diameter. I would rather not use a 1/2" screw to mount cabinets. This is NOT an application for drywall screws - they are hardened to penetrate drywall and will often snap in in this type of application. There are longer cabinet mounting screws available, but they may be a little hard to find.

[All Thumbs]

Look for the 3-1/2" to 4" SPAX screws at Home Depot. They have a Torx (star) flat heat. The SPAX design works well for driving longer screws. It requires less torque and the Torx head prevents camming-out.

[pelligrini]

Most horizontal electrical runs are done near outlet heights. You'll probably be safer having the power off while you're driving your fasteners.

I don't think going from 3" to 3 1/2" would make too much difference. Plywood can take and hold a fastener. Allthough it's not as good as going into solid wood, plywood has some pretty decent holding power.

Use some lube (soap) on your screws, especially if you go with longer ones. Hope you're using an impact driver.
If not, sounds like a good opportunity to get a new toy.. er.. necessary tool.

[cabinetman]

I like to use a coarse thread screw that's threaded to the head. Spax are good and so are other coarse thread that are similar to drywall screws (which have greater thread separation than spax). I'll use either a phillips or square drive flat head, and the length should be at least long enough to bed the screw into the stud ⅓ the length of the screw.

A few suggestions on installing. I take a measurement of the width of the cabinet. I'll mark the wall for the length. I find the studs and make a mark on the wall for the center of each of the studs. Then I go to the back of the cabinet and measure off from one end where the studs are and pilot a small hole through the hang rail.

A base cabinet is positioned below, with dead men boxes on top to set the height of the cabinet. If a base cabinet or other form of support isn't available, I'll install a level cleat for the cabinet to rest on. I'll use an adjustable extension brace to hold up the front of the cabinet so it sits against the wall. Once in place, install the screws through the hang rail to the studs.

I use a cordless drill on slow speed to drive the screws. I haven't found it beneficial to use an impact driver. Threaded screws seat real well when driven smoothly. The trick in driving screws is to not spin them fast. When the screw is close to tight, just bump the trigger to pull up tight. Cordless drills seem to have a better torque range at slow speeds than corded drills.

.

[skamath]

Thanks for all the replies! I left out an important point. These are for garage cabinets. I might be putting some heavy items in these cabinets.

[cabinetman]

Thanks for all the replies! I left out an important point. These are for garage cabinets. I might be putting some heavy items in these cabinets.

If you've assembled and installed them properly they should hold reasonable weight.

.

[cwsmith]

I'll add my vote for using Spax screws. The Torx head Spax that I have purchased at Home Depot are self-drilling and lubricated and have great holding power and can handle pretty decent weight.

If you're concerned with electrical wiring, it might well be worth the time to sweep the area with one of the modern stud finders that also detect hot wiring.

I'm for not using a impact driver and prefer using a cordless drill-driver. Probably just me, but I get a much better "feel" for how the screw is setting.

I hope this helps,

CWS

[Cochese]

Love the Spax stuff. My preferred screw for everything.

[cork58]

Probably to late by now but I hung all my "stuff" using the cleat system seen here link: http://www.woodmagazine.com/ideas/wo.../idea-shop-52/

When I said stuff, I mean anything that was hung on a wall. With this system you don't need to worry about the strength as it is spread out over the entire wall or as much of the wall you use. I'm very happy with the fact that if I decide that the pegboard panel and the sandpaper cabinet need to change places its as eazy as just moving them, they are just hanging!

Just my thought.

[JimD]

The holding power is not very dependant on the screw for anything other than holding the cabinet to the wall. This was made very apparent to me when I was installing the new cabinets into our Pittsburgh house. I pulled the cabinet that held most of our plates and glasses. It was about 3 feet wide and very heavy when loaded. It was held up by 2 screws. There had been two others but they were screwed into the waste stack from the upstairs bathrooms. So by the time I replaced the cabinet, they had rusted away. I removed the damaged drywall and hung the new cabinet to the studs. No way would two drywall screws hold that load. But with the cabinet tight to the drywall, it never budged.

I wouldn't try and go more than an inch into the studs. And I would be sure it is studs you are screwing into.

Jim

[cabinetman]

And I would be sure it is studs you are screwing into.

Jim

What else is important is to make sure the screw is in the center of the stud, and driven in straight.

.

[skamath]

thanks everybody for their replies. sorry i have been not been able to respond before.

here's the screw i am using.
http://www.woodcraft.com/Family/2020...Head-Zinc.aspx

i will check out the torx spax screws. for now thought i'll probably stay with the 3" screws based on the replies. i am using impact driver but i am pretty sure that the screws are going into the studs right about near the center.

turns out i have few more questions and instead of creating multiple threads i'll post in the project related discussions forum.

thanks again!