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All Replies on Pocket holes for floating shelf?

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View adtyug's profile

Pocket holes for floating shelf?

by adtyug
posted 07-12-2018 07:16 PM


21 replies so far

View Andybb's profile

Andybb

1884 posts in 960 days


#1 posted 07-12-2018 08:10 PM

I’d use pocket holes but I’d probably go with longer screws.

-- Andy - Seattle USA

View clin's profile

clin

1025 posts in 1353 days


#2 posted 07-12-2018 08:12 PM

A pocket hole screw is just a screw at an angle. So if a single screw in each stud is enough, so would pocket screws.

The problem I see is that the top is only 1” thick. The screws can easily handle the forces. But, it’s bound to compress the wall board and the shelf itself slightly. So the shelf won’t fall off the wall, but I think it will sag. You could of course angle the back edge so it would tilt up slightly, then sag would level it, but how much you would need would be trial and error, and it likely wouldn’t stay level over the years.

I like your idea of sinking rod into the studs. Make these go into the studs as deep as possible and into the shelf as far as possible. If you get that level, I think it will stay level. The reason for going deep in both directions is to spread the forces over a larger are and reduce the tendency of the rod to compress the wood over time and then sag.

While the shelf is decorative, if it is within reach, someone will put their weight on it. Whether this is child trying to climb it, or your drunk brother in law trying to hold himself up, you still need to consider the possibility.

-- Clin

View Bill_Steele's profile

Bill_Steele

505 posts in 2088 days


#3 posted 07-12-2018 08:26 PM

I’m not sure if pocket holes would be sufficient if only used from the bottom. Perhaps if they were used on both sides that might provide some balance. I would be concerned that force applied to the top (pushing down toward the floor) would make it easy to pull the back edge of the shelf away from the wall.

A few years ago I made a couple decorative floating shelves. The mounting option I chose was a mortise the length of the shelf along the wall side and then a tenon (same length) that was mounted to the wall and fit into the mortise in the shelf. I put a few screws through the top of the shelf into the tenon to hold the shelf to the tenon. These shelves are really only strong enough to hold light weight decoration items.

View Andybb's profile

Andybb

1884 posts in 960 days


#4 posted 07-12-2018 10:48 PM


A pocket hole screw is just a screw at an angle. So if a single screw in each stud is enough, so would pocket screws.
- clin

True but he said that the shelf wouldn’t have to support much weight. Using a Kreg jig to adjust the the depth of the pocket and a 3-4” wood/deck screw with a pilot hole and washer on it should be sufficient. I’d use a straight edge to make sure the wall is flat first. If it’s 5’ long that should give you at least 3 studs.

-- Andy - Seattle USA

View BFamous's profile

BFamous

315 posts in 477 days


#5 posted 07-13-2018 01:13 AM

I wouldn’t do it that way…
I’d be more prone to figure out where the studs would be, then drill 1/2 wide x say 2” deep holes through the outside edge of the shelf. Then I’d drive 5” screws straight through the board via those holes. This gives you 3” of lateral support within the shelf, and roughly 1.5” in the stud (remember, the first 1/2” of wall is drywall, which is good for holding nothing…).
You could then either plug the 1/2” holes, or put a decorative trim piece on to cover them.

Probably still not as strong as I would like, but better than pocket screws IMHO. I also just don’t like the look of a 1” thick shelf either, I’d prefer 2” which gives more options for attaching….

note, on this method you could also have screw holes aligned in between studs and use drywall hanger / toggle bolts for additional support… They would also help prevent sag, due to the nature of the toggle on the inside of the wall.

-- Brian Famous :: Charlotte, NC :: http://www.FamousArtisan.com

View cracknpop's profile

cracknpop

341 posts in 2706 days


#6 posted 07-13-2018 02:14 AM

I think pocket hole screws will be just fine in your situation. Your board is likely to weigh less than 10 pounds. With it only projecting out 5”, and you’re not putting on alot of additional weight, I believe pocket hole screws in each stud will hold fine.
However, I would recommend using longer screws as you need to get through the drywall and into the stud. I would also put the pocket holes on top of the shelf so the angle of the screws are down. I think putting holes on bottom of shelf will be a weaker mount compared to angling screws down. You can fill holes with plugs

-- Rick - I know I am not perfect, but I will keep pressing on toward the goal of becoming all I am called to be.

View adtyug's profile

adtyug

3 posts in 311 days


#7 posted 07-13-2018 12:52 PM

I had considered using longer screws. I guess now my bigger concern is that weight compressing the wallboard and causing the shelf to sag. And, Clin, you bring up a good point – as much as my wife and I would be careful not to put excessive weight on it, we have plenty of dumb friends that would. Thanks for your input, guys.

View bilyo's profile

bilyo

648 posts in 1459 days


#8 posted 07-14-2018 02:02 PM

How about using something like this:
They also have a similar bracket that is heavier duty.

View clin's profile

clin

1025 posts in 1353 days


#9 posted 07-14-2018 02:54 PM



How about using something like this:
They also have a similar bracket that is heavier duty.

- bilyo

While that would be relatively easy to use, the small footprint of the bracket still applies force to the drywall in a way that if the drywall gives at all the shelf will sag. Of course, it may very well be that the drywall will hold up fine.

-- Clin

View Bill_Steele's profile

Bill_Steele

505 posts in 2088 days


#10 posted 07-14-2018 04:14 PM

I think those supports that @bilyo pointed out are pretty good. I believe they are intended to be mounted to studs and not to the drywall using an anchor. You should use several over the 5’ run of your shelf. The only thing is that the supports require a shelf thickness of 1 1/8” to conceal the hardware and you might want to make the shelf slightly deeper—say 5.5”.

View clin's profile

clin

1025 posts in 1353 days


#11 posted 07-14-2018 10:07 PM



I think those supports that @bilyo pointed out are pretty good. I believe they are intended to be mounted to studs and not to the drywall using an anchor. You should use several over the 5 run of your shelf. The only thing is that the supports require a shelf thickness of 1 1/8” to conceal the hardware and you might want to make the shelf slightly deeper—say 5.5”.

- Bill_Steele

I realize they mount to studs. My point is that the weight is trying to bend the bracket down. This will compress the drywall on the lower edge of the bracket (between the bracket and the stud). If the drywall compresses much at all, the bracket will tilt. I don’t think the weight of the shelf and typical knickknacks would cause this. But if the shelf is within reach, someone may put their weight on it. Heck, if I installed it, I’d probably reach up and grab it to help pull myself up after bending down to pick up my tools.

It’s simply the problem you get when the effective height of a supporting bracket is so small (less then 1”). It’s very much a leverage problem. A very short lever arm created by the short height of the bracket resisting the relatively long lever of the bracket extending into the shelf. So any force applied to the shelf is multiplied by the ratio of these “levers”. I think this would be in the range of 10:1 for a load along the front edge of the shelf.

So if someone put some of their weight, say 50 lbs, on the front edge of the shelf, it might put 500 lbs on the the nearest bracket. This force will concentrate on the lower edge of the bracket. Drywall compression strength is surprisingly low at about 400 PSI according to this link:

https://www.americangypsum.com/sites/default/files/documents/GA-235%20Gypsum%20Board%20Typical%20Mechanical%20and%20Physical%20Properties.pdf

So 500 lbs concentrated along the very edge of a small bracket would easily compress and begin denting the drywall. As it did this, the load would spread out over a larger drywall area under the bracket and would reach some equilibrium and stop, with the bracket tilted down. Of of course, maybe it crushes the drywall completely under the bracket.

I’d certainly consider those brackets and my guess is they would be just fine for the intended application (excluding the size issue Bill pointed out). I’m just pointing out what I think might happen and why.

-- Clin

View Bill_Steele's profile

Bill_Steele

505 posts in 2088 days


#12 posted 07-15-2018 12:39 AM

I see your point—all the energy is focused on small points of contact. I guess a stronger option would be a steel pin or large dowel that goes through the drywall into the stud.

BTW: I really like your blog on the Spanish gate—fantastic looking gate!

View ArtMann's profile

ArtMann

1359 posts in 1173 days


#13 posted 07-15-2018 07:46 PM

My answer is no. They are not appropriate for a floating shelf – even one with zero weight to support.

View bilyo's profile

bilyo

648 posts in 1459 days


#14 posted 07-17-2018 01:22 AM



I see your point—all the energy is focused on small points of contact. I guess a stronger option would be a steel pin or large dowel that goes through the drywall into the stud.

- Bill_Steele

As I said, they also sell a heavier duty version. It includes a pin on the back that goes into a hole drilled into the stud. It should hold quit a bit more.

View TheFridge's profile

TheFridge

10858 posts in 1843 days


#15 posted 07-17-2018 04:47 AM

I wouldn’t trust it.

And if i were to drill into a visible part Is do it from the top. But I wouldn’t. Because after you screw it you’re going to have to glue, trim, shave, sand, and finish in place.

I’d rather use brackets of a sort.

-- Shooting down the walls of heartache. Bang bang. I am. The warrior.

View clin's profile

clin

1025 posts in 1353 days


#16 posted 07-17-2018 04:37 PM



As I said, they also sell a heavier duty version. It includes a pin on the back that goes into a hole drilled into the stud. It should hold quit a bit more.

- bilyo

I didn’t noticed that either. Here’s the link I found to it on the Rockler site. It would do the job because it extends a rod into the stud. A bit pricey at $20 a pair. Maybe you could get by with a single pair. It would certainly be strong enough to support the shelf. But I’d be concerned the 1” shelf would sag over time.

http://www.rockler.com/i-semble-heavy-duty-blind-shelf-supports

Lot’s of things on Amazon. I found these that I think you put an anchor into the stud, then screw the post into that. $18 for a set of 10. Not sure if for wood studs or perhaps masonry wall.

https://www.amazon.com/BAKTOONS-Concealed-Floating-Supports-Invisible/dp/B07CPPYTS8/ref=sr_1_13?ie=UTF8&qid=1531845086&sr=8-13&keywords=blind+shelf+bracket

-- Clin

View bilyo's profile

bilyo

648 posts in 1459 days


#17 posted 07-17-2018 08:03 PM

Let’s not lose sight of the fact that the OP said that the shelf will be only 5” wide, will be decorative, and will not carry a lot. While the concealed supports from Amazon look like a good solution, I think his idea to use threaded rod would be more than adequate. My gut says that 3/8” rod should be good.

View dhazelton's profile

dhazelton

2837 posts in 2653 days


#18 posted 07-17-2018 10:07 PM

Put in a couple of lag screws as straight as possible and cut off the hex heads with a hack saw. Drill holes in the shelf and slide it over the lags.

View Robert's profile

Robert

3367 posts in 1837 days


#19 posted 07-18-2018 03:35 PM

No.

First, pocket screws are meant to be used on endgrain. Using in long grain is subject to fail depending on wood it will split.

Second, even with a long screw, you’re only capturing a small amount of wood.


Put in a couple of lag screws as straight as possible and cut off the hex heads with a hack saw. Drill holes in the shelf and slide it over the lags.

- dhazelton

Now I like this idea :-)

All that being said, screw it up there and see what happens….................

-- Everything is a prototype thats why its one of a kind!!

View DS's profile

DS

3134 posts in 2777 days


#20 posted 07-18-2018 03:55 PM

Hafele has an adjustable shelf support rod for this application.
It works fairly well.

-- "Hard work is not defined by the difficulty of the task as much as a person's desire to perform it.", DS251

View oldnovice's profile

oldnovice

7475 posts in 3724 days


#21 posted 07-18-2018 06:02 PM

How about a long French cleat?

-- "I never met a board I didn't like!"

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