ChuckS said:
Never handled a DDF40, but when do you plunge twice? After the dry fit right in which adjustments are found to be necessary? And that means you have to identify and mark the holes concerned, if there's more than one and go back to the drilling process for those holes and boards, a step not usually required with the DF500 when the wide mortises are cut.
I don't know which system is better for cabinetmaking, but on the aspect of doing (plunging) it right the first time, one can't deny that the DF500's tight-loose setting really gets it.
Whether or not and "when" double plunge will depend on several things
1.The the individual = doing the layout and plunging (how accurate that person is) the more accurate you are here the less double plunge will be needed.
2. The method of indexing = (jig or pencil mark) If using a jig that will locate the DDF accurately then NO double plunge is typically needed.
3. How accurate (flush) the ends need to be. = This tends to be the biggest driver for me on the double plunge. Typically even if the dowels are only off a little you can still mate the pieces. However the ends being perfectly flush will be where the joint suffers "slightly" This also depends on how OCD a person is and the piece. Sometimes a piece is trimmed or sanded in after so its a non issue. Also when I say "slightly" I'm talking about .008"ish. I just did a piece yesterday that was about 32" long and had 8 dowels (4pairs) laid out by hand with a pencil and the ends were off by maybe .006" just enough to slightly catch a finger nail. The parts were cut on CNC and laminated so no sanding or final trim was planned and they were exact same length. If you are in a situation that requires "perfectly" flush ends then double plunge probably from the start.
4. Joint complexity = The more dowels and/or corners you have coming together the more likely you will benefit from double plunging. After awhile you develop a little voice in the back of your head that tells you when to double plunge. If your worried I would say double plunge from the get go it only takes a couple extra seconds the 2nd plunge is taking off so little you hardly even notice. I would do one side of the joint with single plunge (on the mark) and double plunge the the other piece (place cursor on either side of the pencil mark.)
There is no doubt that the Domino provides a wider margin of error and is a great machine. It was actually my gateway tool into the Festool brand and still own it. However for me personally I find the middle setting to sloppy for my taste. I am typically pretty darn close on the layout and dont require such a large margin so I use the tight setting anyways. This is also my biggest wish for the domino is to have a "variable" Instead of perfect/sloppy and supper sloppy. Does anyone even use the super sloppy ?
For me its like picking the favorite kid, and neither are perfect. Here are my biggest likes/dislikes for each
consumable cost= there is no denying that dominos are considerably more than a dowel typically 4-5x this adds up over time
Mafell has better fence both in adjustability and locking (I wish the domino also had a micro adjust height control for fence)
The Mafell can drill "all" the system holes with one tool. No LR32 is needed. (However I have a lot of love for the LR32 too)
The Mafell has a lot larger range up to 12mm and since its a round hole the 40mm depth is irreverent I have used the DDF40 to do the locating and drill the pilot hole and for heavy duty projects I simply run a longer drill bit down the hole and use dowel rod custom cut. easily getting 12" of length if needed. So im my opinion it bridges the gap between the 500 and 700 in one machine better.
Plunging Ill give the edge to the Domino but its close, really close. The DDF is harder to plunge on the first plunge but you do develop a technique the second plunge if needed is like plunging into butter. The domino requires less effort or force but slower feed rate.
Exposed fastners hands down the Domino wins here and truthfully the only reason I hang onto the Domino. I can do everything with the DDF that I can do with the Domino just as fast EXCEPT have an exposed domino. I will never do another dovetail drawer The Domino is a speed demon for making exposed Domino drawers. Drawers with no dovetails or no visible joinery looks cheap to me. However so does a exposed dowel IMO but a exposed Dominos look really really nice IMO. Its a toss up for me which I like better for best looking drawer box but the combination of speed and looks the Exposed domino drawer wins over a dovetail drawer every time. Even though I have never scientifically tested the strength of either I wouldnt be surprised if the exposed domino wasnt stronger. However at that point its debatable strongest vs. strong enough as the wood will likely fail before the joint.