dowel joints create wobly joint: not enough glue?

[Chris Padilla]

I use dominoes instead of dowels but the assembly is the same. I like to insert the dominoes into one side first, with glue, being careful to wipe up squeeze out. Sometimes this will be minutes ahead of time and other times it could be hours or a day or two ahead of time. Depending upon the complexity of the glue-up, I might do it in stages but use the other pieces dry just to hold the shape correctly of the glued pieces. If your dowels fit incredibly tight, you might have starved glue joints. The point is to minimize the length of time before you get your clamps on so I do everything I can to minimize that time. I often do dry runs; always have my clamps ready to go; glue ready to go (upside down so glue flows right away); brushes ready to go; damp sponges or towels for wipe ups; no disturbances from the family. You'll mess up a few glue-ups and eventually figure out a good system that works for you. Always keep in mind that the glue needs some room, too, so if joints fit so tight that getting them apart dry is a struggle or extremely difficult, then your joint is too tight.

[Mark Bolton]

Thanks everyone for the advice. Mark, your post was very detailed and helpful. I will use your method along with Adrian's. while it might be theoretically better to make sure all the dowels are coated uniformly, that won't matter if you take too much time to clamp them.

I didn't realize there was a difference between parallel and bar clamps. You just saved me some money. Something like the Jorgenson I bars will work, no?

http://www.amazon.com/Jorgensen-7236.../dp/B0000224CH

Im probably well represented in the archives as a firm believer that parallel clamps are a complete and utter waste of money. Our go-to clamps are the 3/4" pony pipe clamps and the Ibars you posted. You can put together three of four of the 3/4" pony pipe clamps for the cost of a single parallel clamp. I just dont see the value (in parallels). You always need more clamps than you have so if I were going to populate my shop with 20 parallel clamps I would rather have 60-80 really nice pipe clamps. The I bars are invaluable and if you are on a one for one comparison I see no comparison. I know this wont ring true with many here but I would much rather spend my money on Ibars and 3/4" pony pipe clamps.

[Chris Padilla]

I do love my Bessey parallel clamps!! I've never had a situation where they could not pull something together BUT then again I am not a professional and don't rely on them to make a living. I do rely on them to keep me out of trouble and in the comfort of my garage/woodshop.

[Mark Bolton]

I use dominoes instead of dowels but the assembly is the same. I like to insert the dominoes into one side first, with glue, being careful to wipe up squeeze out. Sometimes this will be minutes ahead of time and other times it could be hours or a day or two ahead of time. Depending upon the complexity of the glue-up, I might do it in stages but use the other pieces dry just to hold the shape correctly of the glued pieces. If your dowels fit incredibly tight, you might have starved glue joints. The point is to minimize the length of time before you get your clamps on so I do everything I can to minimize that time. I often do dry runs; always have my clamps ready to go; glue ready to go (upside down so glue flows right away); brushes ready to go; damp sponges or towels for wipe ups; no disturbances from the family. You'll mess up a few glue-ups and eventually figure out a good system that works for you. Always keep in mind that the glue needs some room, too, so if joints fit so tight that getting them apart dry is a struggle or extremely difficult, then your joint is too tight.

Chris,
When you have squeezeout that you have to wipe up around a tenon, domino, dowel, you basically seal the joint. Especially if its days before the rest of the joint is assembled. There of course may be some benefit there if you really clean the daylights out of the area but again, man, that seems like a lot of work (for a compromised joint) unless you have such a complex glue-up that there is no other choice.

I cant imagine that I could clean up a doweled joint well enough to feel like all the surfaces are going to accept glue as well as if they were raw.

[Chris Padilla]

I rarely have much squeeze out. You just have to be careful with the amount of glue you squeeze in. Appreciate that I'm not (wife may beg to differ! ) really on any time crunch and even when I have squeeze out after driving the dominoes home, it ain't much. There is plenty of "non-spoiled" wood fibers for the glue to grab onto when I do my full glue-up.

[Mark Bolton]

Thanks everyone for the advice. Mark, your post was very detailed and helpful. I will use your method along with Adrian's. while it might be theoretically better to make sure all the dowels are coated uniformly, that won't matter if you take too much time to clamp them.

I didn't realize there was a difference between parallel and bar clamps. You just saved me some money. Something like the Jorgenson I bars will work, no?

http://www.amazon.com/Jorgensen-7236.../dp/B0000224CH

Again, a shallow carcass glue up is different but usually (at least with straight fluted dowels) when you peck the dowel into the hole the glue will squeeze out into little pearls at every flute (unless youve got way too much glue in the hole then its a puddle around the dowel). This (to me) means that the glue has basically come up all sides of the dowel and its nearly completely coated except for perhaps the very tips of the flutes. Regardless, it would seem a lot faster to glue the dowel bores and stick an acid brush in there to swab the holes as opposed to brushing each dowel.

Dont know, its just about speed in my opinion. Of course quality and joint integrity as well, but those are a given.

[Phil Thien]

I squeeze glue into the dowel holes and they use a skewer to make sure the walls are evenly coated.

I use white glue so I have longer open time.

[Paulh Tremblay]

I added two Miller dowels per joint to the cabinet that had the slight wobble, and it still wobbles. Very interesting. It makes me think that most of the rigidity of my dowel joints comes not from the dowels, but from the glue to the surface. That further makes me wonder if dado joints aren't in fact better. If you performed a test in which you tried to tear apart the cabinet, dowel joints would easily prove stronger. However, cabinets are not usually stressed in this way.

Instead, cabinets are stressed by forces acting to make them out of square. Here, dadoes provide much more strength.

[Roger Rayburn]

Your wobble description suggests to me that your dowel holes are perhaps a tiny bit too shallow, as Mark suggests, and therefore it is impossible to completely seat the edges to each other. This is the same concept as a mortise & tenon. A joint with a shoulder is more stable than just a stick in the hole. Once the glue is dried, nothing should move. And, shoulders on M&T joints don't get glued. The stability depends on the glued stick in the hole and the unglued shoulder.

[Mark Bolton]

I added two Miller dowels per joint to the cabinet that had the slight wobble, and it still wobbles. Very interesting. It makes me think that most of the rigidity of my dowel joints comes not from the dowels, but from the glue to the surface. That further makes me wonder if dado joints aren't in fact better. If you performed a test in which you tried to tear apart the cabinet, dowel joints would easily prove stronger. However, cabinets are not usually stressed in this way.

Instead, cabinets are stressed by forces acting to make them out of square. Here, dadoes provide much more strength.

Its hard to say with any certainty without seeing the boxes and the wobble first hand but I think I recall you saying you had some that you assembled without a wobble. I cant honestly say that any box Ive assembled, dado or not, doesnt have some wobble before the back goes on. After the back is on I would guess I could still say there was some wobble in that you can always flex/spring the open end of the box until its in place/face frame/secured to adjacent boxes/etc.. Id guess the flex to be worse with MDF (I dont build boxes with MDF).

I will acree with you that over thinking the average cabinet box is easy, and often, done. Even a cheap home center box, once installed, can be more than adequately rigid. That said, it would be annoying while assembling them and Id want to find the problem.