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Forum topic by 1thumb posted 10-21-2019 03:05 PM 377 views 0 times favorited 16 replies Add to Favorites Watch
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1thumb

126 posts in 2692 days


10-21-2019 03:05 PM

Question regards upper part,shelves, in rendering. 25.5 deep, 88” h, 80”w are overall dimensions. Trying to avoid cleats. Birch plywood will be used. All gets painted. As is now,no back, but maybe a 1/2” back wouldn’t be a bad idea. All built on site.Pocket screws hold them shelves and/or how would you highly skilled professionals fabricate? Thanks!

https://s3.amazonaws.com/vs-lumberjocks.com/pzqchrl.jpg!


16 replies so far

View bilyo's profile

bilyo

868 posts in 1638 days


#1 posted 10-21-2019 03:43 PM

The floor is going to carry all of the vertical weight of the shelf system. So, I assume, all you are trying to do is overcome any tipping forces and hold the units against the wall. I don’t have any engineering calculations to back it up but, I don’t like pockets screws in this application. You will need longer and larger diameter screws than are ordinarily used in pocket screw applications. Making larger pocket holes in 3/4” material leaves less material to hold the screws and potential load.

You could build in a continuous rail (like a face frame) along the top back that would be screwed and glued into the back of the top shelf and exposed perhaps 3/4” to 1” below the top shelf. Then use that to screw through into each stud. Once painted, it will hardly be noticed as anything other than part of the system.

If you are going to put on a 1/2” plywood back, that will be very adequate for screwing through into the studs. However, if you are going to do that, you should screw the back to the shelf unit rather than use nails. If the screws into the studs are placed just above one of the shelves, they will hardly be noticeable if at all.

View LeeRoyMan's profile

LeeRoyMan

331 posts in 262 days


#2 posted 10-21-2019 03:56 PM

Why the 25.5 depth? I think it’s to deep, and material wise, 24”deep lets you get 2 rips out of a sheet.
I would shorten the depth and put a back on it.
I did something similar. I dadoed all my shelves and screwed them, then used bondo over the holes and seams.
I doubled the material for the (1 1/2”) width and didn’t use a face frame.

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1thumb

126 posts in 2692 days


#3 posted 10-21-2019 04:02 PM


The floor is going to carry all of the vertical weight of the shelf system. So, I assume, all you are trying to do is overcome any tipping forces and hold the units against the wall.

- bilyo

Thank you, bilyo, but question pertains to attaching shelves to verticals w/o using cleats for shelves to rest on and providing adequate strength so won’t sag.

Looking closer at that rendering, it appears that my main concern will be w/the upper and lower full length horizontals. But i dont have to run those full length or if i do, could stack. Cut uprights, put shelf, more uprights then shelf. I’m sure I’ve made absolutely no sense. Thanks!

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1thumb

126 posts in 2692 days


#4 posted 10-21-2019 04:10 PM


Why the 25.5 depth? I think it s to deep, and material wise, 24”deep lets you get 2 rips out of a sheet.
I would shorten the depth and put a back on it.
I did something similar. I dadoed all my shelves and screwed them, then used bondo over the holes and seams.
I doubled the material for the (1 1/2”) width and didn t use a face frame.

Nice.

Reason for 25.5 is because all is existing. I brought up same point re material waste. Odd that its done that way. Existing adj shelf system on top of base cabinet is going away. They hate seeing all holes. And the existing depth finishes out with the band of a coffer ceiling.

I can step the face of upper unit back then attach a 1 by rip from face frame of new to existing coffer band. Save them a bunch of money by doing so. Literally half on material cost.

Thanks

View Lazyman's profile

Lazyman

4080 posts in 1923 days


#5 posted 10-21-2019 04:49 PM

I take it you also don’t want to use dados? That would be the strongest way to do it. I am not one of the “highly skilled professionals” you mentioned ;-) but I think that is how a HSP (and even I) would do it. I think that dados will make it look more professionally done too. If you don’t want to use dados, for most of the joints you can probably just drives screws in the from the other side and simply countersink and plug with a dowel before painting.

While it may work, what I don’t like about using pocket holes for the horizontal shelves is that with the screw angling upwards it is technically possible for it to pull out with enough downward force, especially since you can only go in as far as the thickness of the vertical piece you are attaching it to. Admittedly, it would probably take quite a bit of weight or stress to make that happen. If you screw in horizontally from the opposite side, you can put a much longer screw in (with pilot hole) and it cannot really be pulled out.

-- Nathan, TX -- Hire the lazy man. He may not do as much work but that's because he will find a better way.

View SMP's profile

SMP

1419 posts in 441 days


#6 posted 10-21-2019 05:05 PM

I also normally will dado these and glue and screw/nail from the side. Then faceframe for added rigidity and finished look.

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1thumb

126 posts in 2692 days


#7 posted 10-21-2019 05:07 PM



I take it you also don t want to use dados? That would be the strongest way to do it. I am not one of the “highly skilled professionals” you mentioned ;-) but I think that is how a HSP (and even I) would do it. I think that dados will make it look more professionally done too. If you don t want to use dados, for most of the joints you can probably just drives screws in the from the other side and simply countersink and plug with a dowel before painting.

While it may work, what I don t like about using pocket holes for the horizontal shelves is that with the screw angling upwards it is technically possible for it to pull out with enough downward force, especially since you can only go in as far as the thickness of the vertical piece you are attaching it to. Admittedly, it would probably take quite a bit of weight or stress to make that happen. If you screw in horizontally from the opposite side, you can put a much longer screw in (with pilot hole) and it cannot really be pulled out.

- Lazyman

I agree re pocket screws and screwing in reg screws from opposite side.

I am somewhat dado averse.I’d be doing it in the field w/hand router. Setting up straight edges for router. Doable, but gosh darnit, time consuming and only a slight margin for error. But i think i’m leaning in that direction.Thanks

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wildwoodbybrianjohns

429 posts in 83 days


#8 posted 10-21-2019 05:11 PM

Stopped-dados, even better. Then no need for a face-frame, unless you want to hide the ply edge.

-- Wildwood by Brian Johns: It is wiser to find out, than to suppose (S. Clemens)

View Lazyman's profile

Lazyman

4080 posts in 1923 days


#9 posted 10-21-2019 09:51 PM

A router jig like this from Woodsmith or this one from Stumpy Numbs will make it pretty easy to do. Nice thing about this jig is that you don’t have to find a router bit to exactly match the thickness of your PW.

-- Nathan, TX -- Hire the lazy man. He may not do as much work but that's because he will find a better way.

View joey502's profile

joey502

558 posts in 2053 days


#10 posted 10-21-2019 10:11 PM

Not a professional but… i would use dominos, if you have one and screws from the outside where they will be hidden and glue where they would be visible. The domino depths can be differnet in each part to prevent seeing them from the outside. I am currently building a bed with drawers in the rails and cabinets for my daughter’s room. I am using 40mm dominos for the connections, 15mm deep in one side and 25mm in the other. This keeps the cutter from punching through the visable portions. This method also almost eliminates my usual errors not adding the length that would be needed for a dado, and it is quick.

View 1thumb's profile

1thumb

126 posts in 2692 days


#11 posted 10-21-2019 10:48 PM



A router jig like this from Woodsmith or this one from Stumpy Numbs will make it pretty easy to do. Nice thing about this jig is that you don t have to find a router bit to exactly match the thickness of your PW.

- Lazyman

If I had more of a need I’d do that. I like this:

https://www.youtube.com/watch?v=KdxjjGjt6L0

View Lazyman's profile

Lazyman

4080 posts in 1923 days


#12 posted 10-22-2019 01:17 AM

It looks like you’d be doing over 30 dados. Sound like a need to me. :-)

-- Nathan, TX -- Hire the lazy man. He may not do as much work but that's because he will find a better way.

View 1thumb's profile

1thumb

126 posts in 2692 days


#13 posted 10-22-2019 01:42 AM



It looks like you d be doing over 30 dados. Sound like a need to me. :-)

- Lazyman

Valid point. :-(

View TungOil's profile

TungOil

1343 posts in 1030 days


#14 posted 10-22-2019 01:52 AM

This is a job for dados. Pre-cut your parts in the shop, then assemble on site.

-- The optimist says "the glass is half full". The pessimist says "the glass is half empty". The engineer says "the glass is twice as big as it needs to be"

View DS's profile

DS

3324 posts in 2956 days


#15 posted 10-22-2019 09:05 PM

In my shop these are all blind dadoes.

Glue and screws in the areas that won’t be seen.
Glue and clamps at all the other joints.

Assemble and pre-finish in the shop without the backs attached.
Final assemble after finishing.
Install in logical sections.

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

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