Dowels, how many for a upper cabinet box?

[Ole Anderson]

I am about ready to start constructing the upper cabinet boxes for my kitchen, using the standard 12" depth (I'm reusing the bottom boxes). I have elected to use glue and dowels for the corner joints. I have the DowelMax Jr. jig and plan on using 3/8" dowels. Any hints as to problems to watch out for? Also how many dowels and what spacing should I use on the 12" joints? Oh, the boxes will be 3/4" Hickory plywood edge banded 3 sides with the bottom shelf having a 3/4" solid edge. Backs will be 3/4" Hickory ply set in a 3/8" dado.

[Phil Thien]

I'm just going to say that, a biscuit joiner will make this go a ton faster.

[Darius Ferlas]

Not a believer in biscuit joiners, unless you spend big bucks on a Lamello, so I'd say dowels will be just fine.
For any kind of structural joinery using dowels I opt for epoxy rather than PVA.

[Art Mann]

I think 4 would be more than adequate. I use the original Dowelmax jig and it is a pleasure to use. It is truly a precision instrument and makes dowel joinery easy. On the other hand, I have started using pocket screws for some applications and they are even easier and plenty strong.

[Mark Bolton]

I'm with Phil's concept of simpler is better. These are uppers, AND your using 3/4" to boot!! A dado, glue, and some brads shot through the dados where they'll be hidden and these boxes will be intact after a bomb went off.

All our boxes are 1/2" with dado. Face frames pocket screwed. You could drop one from 6' and it'd handle it.

[Ole Anderson]

I have a Dewalt biscuit jointer, but I really have trouble getting a consistent offset from the edge, plus they really don't offer much strength. I love pocket screws, but these will be euro face frame-less style construction so I don't want a dado or pocket screws showing.

[Phil Thien]

I have a Dewalt biscuit jointer, but I really have trouble getting a consistent offset from the edge, plus they really don't offer much strength. I love pocket screws, but these will be euro face frame-less style construction so I don't want a dado or pocket screws showing.

If you did pocket screws, you could screw from the top and the bottom into the sides, so the only way people would see the pocket screws would be if they were short enough to look up under the cabinets, or if they were tall enough to look at the tops of your cabinets.

The biscuit joint, believe it or not, is probably the strongest and most consistent of all the methods you've named here for cabinet construction, even the dado. This is the application for which biscuits were invented.

[Art Mann]

I don't believe that biscuit joinery is stronger than dowels or correctly applied pocket screws. There are all sorts of published experiments to illustrate this. I have done a few tests myself as well. They were indeed invented for this application and they are probably more than adequate. Using the Dowelmax jig he mentioned is just as easy or easier in my experience.

[Huck Schwee]

Since you already have the DowelMax and are comfortable using it, and I don't think anyone would argue that a biscuit it stronger than a dowel, I would go ahead and use that method. I agree with Art that 4 per joint line would probably be more than adequate.

Good luck!

[John Lanciani]

I'll throw it out just for sport; Dominos. Faster and stronger than dowels, just as fast and stronger than biscuits.

[Mark Bolton]

I'll throw it out just for sport; Dominos. Faster and stronger than dowels, just as fast and stronger than biscuits.

Biscuits have no strength. Alignment aid only. Strength is not required in this application, alignment "may be" an asset but not really. Glue alone would suffice.

[Phil Thien]

Biscuits have no strength. Alignment aid only. Strength is not required in this application, alignment "may be" an asset but not really. Glue alone would suffice.

I guess if something becomes repeated often enough people begin to think it is true.

Biscuits make a but joint about a million times stronger than it would otherwise be.

[Phil Thien]

I'll throw it out just for sport; Dominos. Faster and stronger than dowels, just as fast and stronger than biscuits.

In the case of sheet goods, the biscuits wider profile will likely allow a biscuit to match a Domino for strength.

[Phil Thien]

I don't believe that biscuit joinery is stronger than dowels or correctly applied pocket screws. There are all sorts of published experiments to illustrate this. I have done a few tests myself as well. They were indeed invented for this application and they are probably more than adequate. Using the Dowelmax jig he mentioned is just as easy or easier in my experience.

The published tests to which you refer never seem to feature carcass construction.

I guarantee you that if you go into any cabinet shop cranking-out kitchen cabinets anywhere in the country, you will see them using dados, or biscuits.

Finally, in terms of speed, we can have a contest. You dowel your pieces, and I'll biscuit mine. By the time I'm glued-up and in clamps, you will still be drilling holes.

[Art Mann]

Are we not taking about carcass construction? Perhaps you are right but I have used both. Have you? I am not talking about some cheap doweling jig that requires a lot of measuring and adjustments. I am talking about a Dowelmax. Many years ago, I worked at the largest cabinet shop in the Eastern United States (www.wellborn.com). They built for companies like Home Depot and for large apartment complexes. I never saw a biscuit or biscuit cutter while I was there. I did, however, see horizontal gang boring machines for dowel construction. I will admit that is not the same thing as one off small shop construction. More recently, I have visited and done business with a couple of smaller cabinet shops in my community and I have yet to see a carcass put together with biscuits. More and more, I am seeing pocket hole joinery and cam lock for the cheaper assemblies.

[Phil Thien]

Are we not taking about carcass construction? Perhaps you are right but I have used both. Have you? I am not talking about some cheap doweling jig that requires a lot of measuring and adjustments. I am talking about a Dowelmax. Many years ago, I worked at the largest cabinet shop in the Eastern United States (www.wellborn.com (http://www.wellborn.com)). They built for companies like Home Depot and for large apartment complexes. I never saw a biscuit or biscuit cutter while I was there. I did, however, see horizontal gang boring machines for dowel construction. I will admit that is not the same thing as one off small shop construction. More recently, I have visited and done business with a couple of smaller cabinet shops in my community and I have yet to see a carcass put together with biscuits. More and more, I am seeing pocket hole joinery and cam lock for the cheaper assemblies.

Yes, I have used both. I'm a big fan of dowel joints, and good dowel jigs. I have a very nice Jessem doweling jig (and several other nice doweling jigs), and I've even posted here about doweling jigs I've made myself.

Biscuit joiner still wins for this application, IMHO.

[Ole Anderson]

Take this with a grain of salt as it was done to justify dowels, but here are some strength test comparisons: http://www.dowelmax.com/jointstrength.html

Not real scientific as only one or two samples were tested and more details of assembly and gluing would be welcome as well as mode of failure and closeups of the failed joints as well as a bigger gauge and a smooth application of pressure, but not bad for a workshop test. Short of what you would see in an engineering lab where stress and strain would be plotted to failure. Interesting that in the first mortise and tenon joint test, the base wood split before the joint could fail. A better selection of uniform wood using straight grain quarter sawn Oak would also have been my choice for the test.

As stated, not entirely applicable to case work joinery using sheet goods.

[Mark Bolton]

Biscuits make a but joint about a million times stronger than it would otherwise be.

I guess I should have stated with regards to case construction. If we are talking about biscuiting an entire upper together than we are really loosing it. That would take exponentially more time. The issues around the butt joints in the box assembly with alignment front to back, clamping tight, sitting in clamps, and so on make dado construction even more clear for a small shop but thats just my opinion. Forget about the fact that dado's and rabbets add massive amounts of strength and rigidity to the box while serving double duty of hiding little bits of tearout and triple duty of facilitating alignment. All that aside, for me the big issue is speed. The assembly time after machining would be seconds compared to minutes.

I have no problem with anyone building a box with biscuits, dowels, domino's, sliding dovetails, cabinotch, whatever.. Its just my experience that you really cant beat dado and rabbet construction for speed and rigidity in a small shop that doesnt have dedicated produciton-type machinery for accurate boring, machining, clamping.

My only point was with the surface area available using 3/4" ply for uppers glue alone would hold those boxes together for a lifetime. Over complicating it is up to the individual.

[John TenEyck]

I've built cabinets lots of ways and biscuits have been the easiest by far for kitchen cabinets. Dados/rabbets require extra machining (and material) after the parts are cut out, biscuits or dowels do not. OK, you have to cut the biscuit slots or dowel holes instead, but you don't have to guide those big parts over a saw or router table, you bring the tool to the part. When I built my kitchen I could cut all the biscuits slots for an upper cabinet, 3 per corner per part, in less than 5 minutes and that included getting the parts. We're only talking 24 cuts, with only 4 set ups. A dowel jig? Wouldn't even be close unless you had one with 8 bushings all set up and an arrangement so that you only had the same 4 set ups like with the biscuit approach. I don't even know if someone makes a jig like that since I don't care much for dowels. I've used a fair number of pocket screws, too, and I like them a lot, but a biscuit joiner is far faster for me for kitchen cabinets.

I also disagree with the comment about reduced chipout if you use rabbets/dados, that has never been my experience unless I use a router but that would be my least preferred approach in terms of speed. I can cut parts off square with almost no chipout using a HATB blade and a ZCI; I've never had a dado blade that could match it, but maybe they do exist if you spend enough money.

As far as strength goes, all those methods are plenty strong enough although I sure wouldn't trust just a glued butt joint, especially with the melamine I prefer to use for the interiors. 3 biscuits per corner with 2 screws where they don't show and the box is bomb proof. Time sitting in the clamps? There is none. You clamp the box up, drive the screws, then remove the clamps and move on.

Ole, get Jim Tolpin's book on building kitchen cabinets. The method he describes in his book makes the registration of the biscuit slots dead simple and dead on. Forget the fence if that's how you've been doing it, everything is referenced off the bottom of the tool, and mating parts are paired together and cut together at one time. It's a pretty simple and foolproof process. And fast.

John

[Prashun Patel]

I used a dowelmax for a row of cabinets. It was fast enough for me. More importantly, it was dead on. One thing i would suggest is running all yr dowels through a plate for consistency or use a drill bit that is a shade bigger than 3/8.

[johnny means]

I'm smirking at all the talk of chair quality construction for upper cabinets. The fact is that a butt joint, glued with three screws per joint will build an upper that will last forever. Any of these techniques will be plenty strong and a waste of time.

[Ole Anderson]

Thanks for all of the comments. Fact is I'm retired so I have the time to take the less productive route and I bought the DowelMax for this project, so that is what is going to get used. I enjoy all of the alternate discussions, but my original questions related to how to best use dowels in upper cabinet construction. An extra thanks to those that helped me on that. Frankly the other technique in the running would be pocket screws, but I want to keep the cab bottoms clean. Please, continue the discussion...

[johnny means]

Ole, my number is 3 dowels per joint. Front, back and one in the middle. This will counter any bowing in your material and be plenty to hold joints tight along their full length.

[Leo Graywacz]

When I do Euro boxes I use 2 in the front couple of inches, one in the back about 1" from the edge and one in the center of those.

[Mark Bolton]

I've built cabinets lots of ways and biscuits have been the easiest by far for kitchen cabinets.... John

Agreed, it all depends on your shop and equipment and as you stated in another thread, a small shop or as Ole has stated he is retired, so cost/benefit is not such a factor. I am by no means a big shop but continually look to that world for clarity an rationale when Im likely over engineering (read: losing money). Building an upper that can handle being filled with lead ingots is fine by me but I cant sell them.

I cant say Ive biscuited many boxes together for a real world comparison because we just don't use biscuits very often. Also our boxes are all prefinished maple ply so its simply not an option (glue). For me its a tool that may come out if the cabinet a few times a year. With recessed bottoms (flush interiors) the biscuit's would simply be too much work (time wise) as well as other factors (tear out). Im not challenging you, because each person works with the tools they have, but in the five minutes to run the biscuits I could have several parts across the slider or through the shaper (feeder) though I know these tools are not in every shop.

True, rabbets/dados can be a bit more work with a table saw. I break down all parts, setup a sharp dado on the slider, and the shaper for the rabbets. Alone, I can machine an entire kitchen in short order.

If everything is sharp (dado) I dont have issues with tearout even without scoring and there is no chance of it on the rabbets run on the shaper (could also be done on a router table). Where I will occasionally get a little is when breaking down parts on cross cuts as blades will dull even over the course of a large job, but all these cuts are buried in a dado or rabbet so its a non issue.

Melamine is a different animal all together and not relevant to the thread as Ole is using hardwood ply as I recall but may be wrong. I too would never trust a glued anything with melamine but its in my shop about as much as my biscuit joiner. As a rule my customers are wood people so the maple interiors are what we run. I dont care for melamine personally for a multitude of reasons, environmental, equipment, weight, and many others.

[Leo Graywacz]

I had a jig made and posted it here a while back.


http://www.sawmillcreek.org/showthread.php?184610-The-Evolving-Build-Of-A-Euro-Cabinet-Cherry-Kitchen