Hi All,
I’m about to start building my own kitchen cabinets. I’m a furniture maker by trade so I think I know what I’m doing (yeah, right). My question is this, most things I’ve read and seen in showrooms have the floor of the base cabinet captured between the sides of the cabinet. As I think about a heavy stone countertop sitting on these cabinets, wouldn’t it be better to attach the bottom of the box so that the sides sit ON the bottom and not next to it.
I’m thinking all that shear force from the countertops is tending to push the sides past the bottom in the standard configuration. Or is this all a moot point because the base under the boxes is holding everything anyway?
Thanks in advance for any insight or advice you might have!
Steve
Replies
that would leave not room for your toe kick...or if you made a toe kick it would make your "floor" much harder to acess.if your concern is the stone top then no, you have nothing to worry about unless your making them out of paper mache.
no papier mache here
Sorry, bad job of describing what I was thinking. Attached is a front view drawing of two cabinets with a continuous toe kick underneath. The basic shape is just a box, with no integral toe kick. The way I was taught, the base is installed first and leveled and then the box is set atop the base with the overhang over the base creating the toe kick. I guess in this case the sides sit on the base and the bottom just closes the box and provides no real support. I recognize the intergral toe kick is by far the more common approach.
And I've given up making cabinets out of papier mache, just too messy. Nice way to use up old newspaper thought. I use 3/4" plywood now.
Steve
If using a base, either one, as sides are directly supported. Exception is where there are toe kicks on front and side (island or penninsula). Then the sides over the base provides better support.
If the cabinets are supported by adjustable legs with a clip on toe kick, then the sides resting on the base is preferable.
The really nice thing about the adjustable legs, is that it makes it easier to add in toe kick drawers, heat registers, cold air returns, vacumm sweep ports, etc.
This nails my question
Thanks Catmandeux,
This is exactly what I was asking.
Gatordoc
dont think you need to be concerned about the weight of your top. Either method will support your conter top without a problem. think you just need to chose what option best suits your needs and best accomplishes the look your going for.
I don't understand why the "shear force from the countertops is tending to push the sides past the bottom". Whether the side laps tihe bottom or the bottom laps the side, the assembly is sitting directly on the base, and no force is present on the bottom (except possbily simple compression force along the edge of the bottom if it laps the side).
You do need the sides/front/back to be held together at the bottom. This can be accomplished by the bottom itself or by a 1x frame under the bottom.
Steve
Furniture generally will weigh more than the contents inside, so I understand why you might come up with your concerns.
I'm anxious to hear your thoughts when you get to the upper cabinets and their tonnage of plates.
As long as you put the boxes together with glue, it is a moot point. Some reinforcement of the joint is also advisable. Your choice there. Dados/tennons, pocket screws, drywall screws, whatever. My personal choice is 15 gage gun nails. Cabinets don't have to be built to the same standards of joint strength as does furniture. Once installed, there is no racking thus no flexing of the joints. Chairs and tables are a different kettle of fish.
Building your own kitchen cabinets
I know there are a lot of ways to build them. I had great success with Norm's CD on the subject. They are very solid with all of the sides, backs, bottoms and tops being 3/4" plywood. Glued and screwed (1 5/8" deck screws). The toe-kick is integrated. I had granite counter tops added and the guy who came to honcho the instillation was quite happy with the boxes. Bought the ply, both sides maple with Ryano top coat, from Paxton. Used a table saw with a dado blade and made one a night after doing my day job. It was great fun and they are still solid after six years. I still had to make the face frames and doors but I believe the fact that they have both a 3/4" ply top and back adds to their strength.
Building your own kitchen cabinets
I know there are a lot of ways to build them. I had great success with Norm's CD on the subject. They are very solid with all of the sides, backs, bottoms and tops being 3/4" plywood. Glued and screwed (1 5/8" deck screws). The toe-kick is integrated. I had granite counter tops added and the guy who came to honcho the instillation was quite happy with the boxes. Bought the ply, both sides maple with Ryano top coat, from Paxton. Used a table saw with a dado blade and made one a night after doing my day job. It was great fun and they are still solid after six years. I still had to make the face frames and doors but I believe the fact that they have both a 3/4" ply top and back adds to their strength.
Check out 'Building Kitchen Cabinets' by Udo Schmidt. It's a Taunton book.
I second that. I used Schmidt's book as my "bible" for building my own. I should add that, if time-pressed, screwing and gluing for most applications seemed to be the ticket -at least in my particular experience.
srructure
gatordoc wrote:
I'm thinking all that shear force from the countertops is tending to push the sides past the bottom in the standard configuration.
Steve
Steve,
Good original question. Not necessarily the right conclusion.
This would only the case if the "standard confiquration" carcass sides were not directly or adequately supported by your seperately built sub-bases and/or kicks.
Let me get back to your original structural question rather than transitioning this into a "how to" thread on cabinet making:
The loads that travel down the carcass sides (and partially, the back) have to be resolved in the supporting floor structrue somehow. When carcass sides w/ standard configurations (or whatever you want to call it) are used, this structural resolution happens DIRECTLY. I believe that is one (among many) reasons why production cabinet manufacturer's utilize this system. Sure, there may be some shims* involved (along with wall anchors) in the final structural assembly, but in most cases the bulk of the axial dead and live loads are carried directly to the subloor via the vertical side panel's bottom edge.
If, however, the cabinet side panels bypass the floor panels (as in a standard confiquraiton) but are not directly or adequately supported by a seperate base system, then the load becomes eccentric to the supporting base member(s). The entire load has to travel through whatever fastening system your side-to-base construction relies on (i.e. nails, screw, staples, glue, tenons, etc.). In that case, those connections are under [tremendous] shear as you hypothosize in your O.P. Yes; that shear can be overcome with adequate construction. But (IMO) it is unnecessary and structurally ineffecient. If you're determined to rely on a cabinet base structure that does not allow vertical loads to travel directly from the side panels to the floor structure For example, you want adjustable posts or intend to build a structurally lean sub base structure, then I believe the best method (as catmanduex pointed out) is to utilize a cabinet floor that runs under the sides. It must, however, be substantial enough to span from under the side panels to any supporting offset posts, seperate base beams, or kicks. It must not itself shear or be prone to distorting. This usually means 3/4" plywood stock which I think this is ineffecient use of material. It will, however, avoid the tremendous shear on connection systems involving standard confiquration side panels lacking integral kicks; particularly when installing granite countertops.
* Any point loading conditions introduced by the use of shims (and resulting increase in shear values) in the case of integral kick side panels would only be of concern at the plywood subfloor structural level. Any point loads shear stress transmitted through the side panel carcass (cabinet level) by the shims are easily resolved in the deep "beam" nature of the vertical side panel.
what would you consider efficient?
deadnuts wrote:
gatordoc wrote:
I'm thinking all that shear force from the countertops is tending to push the sides past the bottom in the standard configuration.
Steve
This usually means 3/4" plywood stock which I think this is ineffecient use of material.
why do you think its inefficient? to much material for the task?
Thanks for asking my opinion
What do I consider effecient? That's a pretty broad question, but I pretty much agree with this definition of effecient produced by dictionary.com.
ef·fi·cient
[ih-fish-uhnt]
ADJECTIVE
1.performing or functioning in the best possible manner with the least waste of time and effort; having and using requisite knowledge, skill, and industry; competent; capable: a reliable, efficient assistant.
2.satisfactory and economical to use: Our new air conditioner is more efficient than our old one.
3.producing an effect, as a cause; causative.
4.utilizing a particular commodity or product with the least waste of resources or effort (usually used in combination)
let me simplify...
let me see if i can simplify my question so that you can understand it.
you said, "This usually means 3/4" plywood stock which I think this is ineffecient use of material". if you consider this inefficient use of material, then what would an efficient material for this application be?
For future reference, when i want clarity on what a words meaning or its uses, ill ask "what does (in this case) inefficient mean?
See. Now you're getting it. If you want a specific response, then you need ask a specific question.
The problem, however, with your question is that "effeciency" implies not only the material itself, but the manner in which is employed. In other words, if the application itself is ineffecient, then its not necessarily a matter of choosing a different material to transform it into an effecient application.
Regardless of your awkward question, I will assume you're referring to the application of running the base cabinet floor under the side carcasses without adequate support near or directly underneath the panel. IMO, this is inherently an ineffecient application which requires ineffecient use of material to resolve. In this case (and most) 3/4" floor material is used to resolve the structural ineffeciency. The the further you move the support away from the axial load, the greater the moment arm becomes. This increase the shear and bending values on the cabinet floor member. A theoretical worst case scenario may be simply trying to support the base cabinet with one post in the center of the cabinet. I not saying that would be done, but In that case, it could probably be structurally resolved (depending on the size of cabinet, load, lateral support, etc)) with an even thicker plywood floor. However, I wouldn't call choosing a thicker floor material a resolution that transforms the application into one of "effeciency" just because it brings the structure into static equlibrium. Get it?
My remarks thus far are soley based on the strutural implications of each cabinet configuration presented in the O.P. and my opinion of their structural effeciency. I will expand my opinion furhter by saying that I feel it is more structurally effecient to bring the sides down continuously to the floor. And most production cabinet manufacturers would probably agree because they do this while employing 1/2" material for the base cabinet floor which is dadoed into the cabinet sides. That's usually because that is all that's need to support whatever is intended to be stored within the cabinet. They are not counting on their cabinet bottoms to do possible strucutural gymnastic by seperating them from the base and relying on carpenters to fiqure out how and where to properly install the supports. To be clear, I'm not saying that seperating the carcass box from the base or running the floor can't be done or that the OP should be building his cabinets one way or the other. I'm simply pointing out the structural implications of each application. You will note that I qualified the appliaiton where the floor runs under the sides with the caveat that the support underneath was inadequate or not direct. If it is directly under the side, then it doesn't matter. You have the same load path as a continuous side and you might as well run 1/2" material instead of 3/4" because the job can be done by either. That asspect alone would constitute more effeciency in terms of use of material.
For the record, I' m not considering each fabricators custom designs, tool set up, shop set up, material they may have on hand, etc. I don't really care about that and I don't need to know htat in order to make my structural point. If you want to discuss those other variables, then go for it...with the understanding that any of those could modify the circumstances which constitute the defintion of effeciency.
numbnuts close but no cigar...
deadnuts wrote:
See. Now you're getting it. If you want a specific response, then you need ask a specific question.
The problem, however, with your question is that "effeciency" implies not only the material itself, but the manner in which is employed.
look at the question. i quote your statement that makes a crazy claim that 3/4'' stock is inefficient and then ask you, what is an effecient material?
guess i should have dumbed it down a few knotches an not assumed that you can deduct that if i am quoting something you said, and questioning you about that statement you would be able to answer a question directly.
you have it backwards, your the one that (not implied but stated) that 3/4'' stock was inefficient (again let me dumb down so you follow) for the proposed box layout gatordoc is suggesting .
Go for it
I've answered your question. In fact, I'll do you the favor of repeating it: (since it seems difficult for you to digest anything other than a sound bite mixed with bravado).
“I will expand my opinion furhter by saying that I feel it is more structurally effecient to bring the sides down continuously to the floor. And most production cabinet manufacturers would probably agree because they do this while employing 1/2" material for the base cabinet floor which is dadoed into the cabinet sides. That's usually because that is all that's need to support whatever is intended to be stored within the cabinet. They are not counting on their cabinet bottoms to do possible strucutural gymnastic by seperating them from the base and relying on carpenters to fiqure out how and where to properly install the supports.”
Before you trip over your own words again in an effort to satisfy your knee jerk tendencies, please realize that the above statements are opinions...and qualified as such. YOu may consider any one of the them to be crazy. and I may feel the same about yours. Neither of those reactionary opinions matter much and do little ot further the topic at hand. However, if you want to question a misrepresentation of fact, then that might actually be worth getting worked up over. So go for it.
And I thought it was easy to build a cabinet.
Your analysis certainly indicates that the decisions involved are complicated. May I conclude that you would advocate for the consult of a cabinet qualified PE? After all, a toppling cabinet loaded down with a granite counter top, is certainly a health and safety issue.
No
sapwood wrote:
Your analysis certainly indicates that the decisions involved are complicated.
Perhaps,f or you, it is. However, I find the structural analysis rather straight forward.
As for your conclusion(s), you are free to make your own. What you are not free to do is apply those (or their resulting assumptions) to me. For the record, I disagree with most of your conclusions. That's mainly because I find they come from an ill informed perspective.
This is da bomb
Deadnuts,
Many thanks for this analysis, it really helps clarify my issue with the structural issues. Since I will be building the base I can ensure that the load on the sides is transmitted directly to the subfloor via the separate base system. This is the (obvious in retrospect) piece that I was missing.
Gatordoc
Many ways to skin a cat.
Depending on the design, you can build your ends to the floor and itermediates on a ladder base.
Work with your cut list in a couple different scenarious. You can save a sheet or two. Also for efficency sake, if you are using ply for all componets. Use shop grade for parts that will not be seen, buy the G2s for the show face.
Please for the sake of DOG don't use melamine crap for the base of your cabs. It is the last place to save a buck.
How are going to finish? Clear, paint, ?
That link to that other forum is really good. That fella has made some incredible millwork.
You should find the thread were he does his own hardwood floor in his house. Knots and medallions, to rattle your socks.
Chuck walks the walk and speaks, to people, not down at others.
Numb nuts ...
you are so full of sh!t your eyes are brown. Where ever do you come up with your answers? You must have an incredibly small for you to feel the need to try to impress innocent HO's with your shallow knowledge. What a marroon.
To the original poster ... do a google search for a delphi forum "breaktime 3" and post over there, you will get much better responses. More realistic.
On my ignore list in only 18 minutes! A new record!!
Cabinet build thread
Steve, here's a thread that will tell you all you need to know re building kitchen cabs..
http://forums.delphiforums.com/breaktime_3/messages/?msg=1442.1
That deadnuts sure is a gas bag.
Joe H