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Discussion Starter #1
Im in the process of re-organizing my garage shop, and I am building cabinets. Currently I have completed 2 cabinets 48x20x36. Im using But joints held together with Pocket screws and Elmers wood glue. and to hang them Im ripping a 2x4 at a 45 degree down the center of the 2x4. And ancord to the wall studes.

I am building all my garage cabinets from 3/4 inch ply using but joints w/ pocket screws.

Is this strong enough for garage storage or should I look at a stronger joint for them???
 

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Sawdust Creator
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Well it should be strong enough for storing bubble wrap, likely not strong enough for housing engine blocks. What are you planning on storing in them?
 

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where's my table saw?
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those are very large cabinets to hang

Upper cabinets I assume? You don't have to hang lower cabinets.:no:
That size of cabinet would stress any joinery method if filled with tools or other heavy stuff...JMO. Rather than your french cleat, a 2 X 4 at a 45 degree rip, I would use a ledger all the way under the bottom and screw them right to the studs using larger flat washers or fender washers.

As to your original question. There are 2 different forces when you hang a cabinet, one is downward from the actual weight the other is pulling away from the wall at a lesser amount. That's why I suggested my method of hanging. The best support for it will be a plywood back, 1/2" or so thick. The back should be glued and nailed to each member on the entire back. The joints holding the top and shelves, will be trying to pull away from the back so it's important that it's glued on.

I have no first hand experience with the strength of pocket screws, but if you use glue it shouldn't make a big difference the screws will help clamp it in addition to providing strength of their own.

How many shelves will be inside? The top will also count as a shelf if you store stuff above. The deeper the cabinet, the harder it is to find stuff unless you use boxes or tubs and have the contents marked on the front ...JMO. How about posting a photo of what you have?
 
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Upper cabinets I assume? You don't have to hang lower cabinets.:no:
That size of cabinet would stress any joinery method if filled with tools or other heavy stuff...JMO. Rather than your french cleat, a 2 X 4 at a 45 degree rip, I would use a ledger all the way under the bottom and screw them right to the studs using larger flat washers or fender washers.

As to your original question. There are 2 different forces when you hang a cabinet, one is downward from the actual weight the other is pulling away from the wall at a lesser amount. That's why I suggested my method of hanging. The best support for it will be a plywood back, 1/2" or so thick. The back should be glued and nailed to each member on the entire back. The joints holding the top and shelves, will be trying to pull away from the back so it's important that it's glued on.

I have no first hand experience with the strength of pocket screws, but if you use glue it shouldn't make a big difference the screws will help clamp it in addition to providing strength of their own.

How many shelves will be inside? The top will also count as a shelf if you store stuff above. The deeper the cabinet, the harder it is to find stuff unless you use boxes or tubs and have the contents marked on the front ...JMO. How about posting a photo of what you have?
Very nice, detailed writeup.
That should pretty well cover all of his questions.

George
 

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Im in the process of re-organizing my garage shop, and I am building cabinets. Currently I have completed 2 cabinets 48x20x36. Im using But joints held together with Pocket screws and Elmers wood glue. and to hang them Im ripping a 2x4 at a 45 degree down the center of the 2x4. And ancord to the wall studes.

I am building all my garage cabinets from 3/4 inch ply using but joints w/ pocket screws.

Is this strong enough for garage storage or should I look at a stronger joint for them???
If you are going to use butt joints and glue, I wouldn't use pocket screws, but rather use a coarse thread 2" (piloted) @ 90° from the outside. If you are concerned about what that would look like countersink and glue in a wood plug. A far superior connection.

To hang the cabinet, I don't use ledger boards. An upper cabinet may sit on a back splash, and that's about all the ledgering I do. If you want to use a french cleat, a 2x4 split will set the back of the cabinet ¾" more in than just using ¾" wood or plywood. Upper cabinets mount to the wall very well with just a hang rail...about 3" high (¾ plywood or solid wood). It is glued and screwed to the top of the cabinets and the sides of the cabinet.

I would use a back to the cabinet. In using a hang rail, a ¼" plywood back will keep the back of the box square. If you are doing butt joints, you can cut the back the exact size as the outside of the box, and glue and fasten to the back edges...and that will square the cabinet.

An advantage to dadoes and rabbets is that once all the machining is done, you have more of a glue surface for the joinery, and the ends of the plywood are covered.

Base cabinets can also be hung, if a toe kick or legs are not wanted.







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Discussion Starter #6
So far I have only built 2 cabinets, and both are 3/4 ply including the back.

When I was doing searches for information on building cabinets I come across multiple sites talking about pocket screws being stronger that 90 degree outside in... Honestly I had never heard of pocket screws until I did these searches.

I did make use of LOTS of them. 6 down each side and 10 across backs and 6 attaching the facing. I did this on all shelves, top and bottom.
 

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pocket screws go into the face ....

where as screws, in from the outside go into the layers of ply. It MAY be that in certain conditions the pocket screws will hold better.... I donno? It's kinda moot at this point since the cabs are already built. :yes:

Dados are my preferred method, but they are more difficult to get perfectly aligned on the back and 2 sides.... not impossible, just more difficult with rabbets and other offsets. I don't usually dado the back because I use a thinner material 1/4" or 1/2", not 3/4". I glue and nail the crap out of the back... :yes:

Some of the additional weight of your cabinets will be in the 3/4" back but it will be OK. Overkill is OK in my opinion. As long as you used glue on all the edges you will probably be just fine. Post back in 25 years to let us know. :laughing:


How about a photo?
 

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So far I have only built 2 cabinets, and both are 3/4 ply including the back.

When I was doing searches for information on building cabinets I come across multiple sites talking about pocket screws being stronger that 90 degree outside in... Honestly I had never heard of pocket screws until I did these searches.

I did make use of LOTS of them. 6 down each side and 10 across backs and 6 attaching the facing. I did this on all shelves, top and bottom.
That may be so, due to the increased leverage. But, then again, leverage is exactly what the joints need to be able to stand up to. Honestly, butt joints may work but, rabbets and dadoes would be a much stronger construction joint for the main structural components.

So either way, butt joints won't provide much protection against racking because there's still all that leverage to break the screw out. Butt joints would be more suited for the stretchers and face frames.
 

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i have many many more cabinets to build. I am building cabinets to cover 2 of the three walls of my Garage.

I opted for butt joints and glue for a couple of reasons, Im not good with dado cuts and using them, and I am using a cheap flimsy table saw because I still dont have room for my bigger table saw, and I still need to make a drive back home to bring that saw to Dallas as well.
 

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two things can happen to your hanging cabinet

One, it may pull out from the wall and remain intact.
Two, it may pull apart from the vertical loads on the shelves.
Neither of which is predictable without destructive testing....:eek:

Racking is not really an issue here in my opinion.

Any weight on top and shelves will put the rear most joints in tension and try to pull them apart at the glue and screw lines. The top shelf will be the first to pull apart in my opinion because it will carry the loads of all the other shelves to some extent.
I suggested a ledger all across and under the back which will help support the vertical loads and reduce them to some extent. It also aids in hanging a heavy cabinet on the wall since the weight is supported and a helper need only push in towards the wall while they are being screw to the studs.

Someone with more engineering than I could make a force diagram which would have the static loads, distributed loads and distances... calculus would be necessary to calculate the forces, should anyone be interested. Not necessary for this project however as "destructive testing" will provide all the info necessary....just sayin' :yes:
 
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i have many many more cabinets to build. I am building cabinets to cover 2 of the three walls of my Garage.

I opted for butt joints and glue for a couple of reasons, Im not good with dado cuts and using them, and I am using a cheap flimsy table saw because I still dont have room for my bigger table saw, and I still need to make a drive back home to bring that saw to Dallas as well.
You can use butt joints and glue. IMO, you don't need math formulas to configure a cabinet to hang on a wall. Post #5 has the basic hanging method.

BTW...Can you post the links to those sites you mentioned about the screws?







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So far I have only built 2 cabinets, and both are 3/4 ply including the back.

When I was doing searches for information on building cabinets I come across multiple sites talking about pocket screws being stronger that 90 degree outside in... Honestly I had never heard of pocket screws until I did these searches.

I did make use of LOTS of them. 6 down each side and 10 across backs and 6 attaching the facing. I did this on all shelves, top and bottom.

ALL of the cabinets we build have 3/4 plywood backs (and sides) that are glued/stapled/ AND screwed to the sides/tops/and bottoms... You ain't pullin THAT off any wall unless there is a nuclear explosion nearby... :thumbsup:

We use pocket screws for faceframes but for general 'box' construction we use 2" screws in any places where they will not be 'seen'...

1/4" backs are only used on 'factory' type cabinets... HomeDepot junk... We don't make that stuff... :no:
 

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I am also planning to build some cabinets for my garage/shop. Good ideas posted so far.
I guess the plan is to rip the plywood so as to get the most bang for the buck...up to 11 3/4 inches wide for the upper cabinets. Add a face frame for strength (glue, clamp and nail).

I have been researching You Tube for ideas. I am not sure if quick, easy to build and strong can all be used in the same sentence. :)
 

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To answer your question, pocket hole joinery is plenty strong enough for shop cabinets. Certain guys hate pocket hole joinery and they will tell you they are junk. This is very untrue. The only downside to them is they can be unsightly. Asking if pocket hole joinery is any good is like asking a Chevy guy if Fords are good. Get my point?

I really like the engine block comment. Most guys just love to hate pocket hole joinery. Go for it. You will not be unhappy as far as strength goes. I have used them a lot in my shop. I don't use them on customer projects. This is mainly because I don't care for that look on fine woodworking.

Mike Darr:blink:
 

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I just went looking for the websites again, and cannot find the site that says they were better...

What sites I did find talk about them being a better choice for a novice, and their reasoning is that it's easier for the novice to assemble with. All of the sites say not to use them in areas where they can be seen, but that to me is common sense.

I would call my experience so far with them a success, and I say that not about strength. Strength is yet to be tested. But I was able to manhandle some pretty good sized pieces of 3/4 ply by myself and still have things come out square.

The first cabinet I built was an experiment, I had never built a cabinet before, and I also had never used Pocket Screws before either... It took me probably 4-5 hours spread over a few days to build the first. The second I was able to cut, clue and assemble the entire cabinet in about 2 hours and on a single evening.
 

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I finally took a couple of pictures. The first one is on the right. I had a few sheets of 3/4 ply that had been cut down for another project, and some 1x6 pine scraps as well.

The one on the left is hung up temporarily to get it off my bench, I had some stuff I needed to work on that was more important that the cabinet.
 

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