Consistent Domino Problem. Help!

[Bryan Hall]

I've been using my domino for a few years now and have got to admit, I think I'm absolutely terrible at using it. It's gotten to the point where I typically dread pulling it out and do everything I can to avoid it, and I'd like that to stop.

My issue is one thing and one thing only. I can never get consistent depth on the mortise location. Left to right alignment is always perfect. Everything assembles without issue. Nothing, however, ever ends up flush on the face.

Example: I was making a screen door today and I dry assembled everything prior to marking out for dominos. The stiles and rails met perfectly flush on the front and back of the door. As you'd expect since it was all planed to the same thickness. With everything clamped up I go through, mark out all of the domino locations, then disassemble.

Next I clamp all of the rails, make their cuts, set them off to the side. Then, clamp the stiles, make their cuts, set to side. Grab dominos, dry assembly. Every single rail sits proud the exact same amount on both sides, probably 2mm. Disassemble, reclamp the rails, sure enough the cutter now will not insert into the previous mortise and wants to cut higher.

So the question I'm dumfounded by is this: Is the fence somehow slipping 1/2 way through the process? If it's slipping, it would be slipping down, towards the cutter, not up (otherwise the rails would sit recessed, not proud) which doesn't seem right, I'd expect the fence to slide up due to the way the machine sits. Or, am I somehow consistently recreating a repeatedly accurate mistake on a large scale? 16 in a row that are off by 2mm and then 16 in a row that are dead on...

This is essentially the same experience I have every time I use the domino, and it's been that way since the day I got it. Occasionally things come together flush, but more often than not I end up double drilling and wondering what the point was in the first place.

I would really appreciate any advice on what I'm doing wrong here.

[Jim Becker]

Some possibilities include the material being just thin enough that the machine is bottoming out on the work surface rather than on the material and not referencing the same face on both rails and stiles, usually the "show face"; front of a door for example. I've occasionally had the first issue with my DF700 and the solution has been to block the workpiece up off the bench so that the Domino machine is always "off" the bench for sure and only supported by the material being pierced.

[Steve Jenkins]

The domino probably doesn’t cut the mortise in the exact center of the edge so you need to mark all the faces so you are indexing from the same face. Same goes for a biscuit joiner.
Jim types faster than me.

[Prashun Patel]

How thick are your pieces? Can you take some photos? It should not be consistently off like this. And 2mm is way too much. Mine are sometimes off but less than 1mm. It’s usually because there is dust on the surface or I am not using dust collection.

When cutting the side grain mortise, there is little real estate to keep the fence from tipping forward. Are you sure your fence is set for 90 degrees exactly?

[Andrew Hughes]

I also experienced the uneven depth with dominos when I first started using mine. I asked a Festool rep about the problem. He suggested holding the tool at end around the cord and pushing from there. It’s worked for me.
much better alignment. With my fingers I can still feel a slight difference but I can feel a few thousand difference with my fingers tips. God given precision instruments.
Good Luck

[Paul F Franklin]

It doesn't sound like a fence slippage problem, even though many users have had to adjust the fence position lock so it locks more securely. If that were the problem you would expect a gradually growing error, not a consistent step change, and as you say, it would likely be in the other direction. But I am at a loss to explain such a consistent source of error. The only thing that may hint at the problem is that the error occurs between the rails and stile. So it could be related to end grain vs. side grain, or it could be a technique issue with positioning the machine on the rails vs the stiles.

You could try doing a bunch of side grain to side grain joints and a bunch of end grain to end grain joints and see if/where the problem shows up.

Or, you could do as I almost always do, and reference off the bottom of the machine rather than using the fence, adding spacers under the stock or the machine as necessary to get the mortise positioned as you desire. I just find this a much less "fussy" way to position things without trying to balance the fence on a narrow piece of stock.

But don't get me wrong...with care and good technique,you should be able to achieve good results doing it the way you describe.

One last thought...is there any chance when you are clamping either the stiles or the rails that you are doing it in a way that the bottom of the machine is hitting something, preventing the fence from registering properly? The edge of the bench or ?

[Bryan Hall]

For referencing:
I have every piece marked "up" and run the domino from the same side for every piece, so it's not a flip flop error (I learned that first thing when I got it).

For clamping interference:
I actually clamp every piece off the edge of my assembly table so there is nothing below the domino to interfere with.

The stiles and rails are all about 1.25" thick and 3" wide.

Wood, in this circumstance, is sapele.

Andrew: I'll give the hand position switch a try.

Prashun: I'll double check the 90 on the fence as well.

Paul: This was also on my mind, the side vs end grain situation. I'll try to set that up this week with some scraps and see what happens. I'll have to look at setting the machine flat on the table. That sounds more difficult in my mind, but maybe hands on would be easier?

I'll try to pull together some photos, but this door is already in glue up so it will have to come from the next wave of trials.

[Jacques Gagnon]

Bryan,

You have already received great advice.

I have good success with the Domino. I use a jig made out of MDF or plywood when working with my 500. Pieces sit on the jig and cuts are made using the jig's surface as the reference plane, with the fence adjusted to sit on top of the wood piece being worked on. A couple of blocks spaced a few inches apart are used as "stops", as well as support for vertical hold downs. This allows me to easily position pieces requiring mortises in end grain when assembling mitered corners.

My understanding of your post is that the problem resides with the "height" of the mortise and not the "depth", correct?

Regards,

Jacques

[Greg Quenneville]

When I had a similar result my error was as Jim described it…the bottom of the machine resting on the bench instead of the fence resting on the stile, which makes that slot too high. Then, since its easy to clamp the rails well clear of the bench, those slots are cut correctly.

Since we aim to get the slot cut roughly in the middle of the workpiece, any such error results in being off by about two frustrating millimetres.

[Michelle Rich]

Veritas/lee valley just came out with a neat jig for the domino. Way cheaper than the Woodpecker 700.00 one. Might help keep your domino level at the attack, and remember to cut with the same side up .

[Malcolm McLeod]

For referencing:
I have every piece marked "up" and run the domino from the same side for every piece, so it's not a flip flop error (I learned that first thing when I got it).
...

This flip flop is the only thing that has bitten me. Please let us know how your testing goes.

[Robert Engel]

Bryan, I had the same issue, checking fence, hand position at end of motor, I still could never get consistently flush joints. I always figured it was operator error, but I could never figure out what I was doing wrong. So I sold it and went back to biscuits. I rarely ever used it for tenons anyway.

I got the best results by clamping the board down and registering off the base, IOW not using the fence.

I figure that's the reason Seneca made the Domiplate to bypass the fence?

[Jeff Roltgen]

+1 on what Jim and Greg said. 2mm is not merely something slipping. It's surprisingly easy for the domino machine base plate to rest on work surface vs. registering the top plate on the workpiece, yet you don't notice it.
No special jigs to buy, simply be sure the workpiece is always hanging off the edge of your workbench.
Dead-level joints is why I grab the Domino machine, and almost never reach for a biscuit anymore.

jeff

[Randy Heinemann]

Given the experience I've had with my Domino, there is only 2 possible reasons for the problem; either user error (and I've had a few) or, if the problem has existed since Day 1 of your ownership, it's possible there is something that was a defect to begin with. Did you have the tool checked out by Festool? I really don't know what the defect could be, but anything which existed from the start of ownership certainly is suspect.

Have you tried having someone watch you while you work on test pieces? They might be able to pick up something you're doing that needs to be changed.

[Dan Friedrichs]

Hold the fence handle firmly. Other hand on the cord, pushing straight forward. Work sticking off edge of bench so that the baseplate doesn't bottom out early. Multiple in-out passes without causing the machine to strain (which may cause it to shift position). Sharp cutter.

I had some poor alignment at first, but with careful following of the above rules, it is now my go-to for getting anything perfectly aligned and dead-flat. It seem to help to regard it as a "precision" machine that benefits from careful, consistent use (vs a "close your eyes and swing it in the direction of the workpiece" tool)

[Bryan Hall]

You could try doing a bunch of side grain to side grain joints and a bunch of end grain to end grain joints and see if/where the problem shows up.



Paul is on to something here, I grabbed some soft maple scraps, 8/4, and did 4 mortises. 2 side grain, 2 end grain. Side to side grain matches perfectly. End to end grain matches perfectly. Side to end grain does not match up.

I also made note that the end grain mortises were slightly loose, while the side grain mortises were a tight fit for the domino.

Dan mentioned multiple passes, which is not the norm for me, so I went back and ran a few extra passes in each mortise. Every one ended up sloppy loose. I figured this was an unfair test, removing the machine and reboring, so I redid all four mortises with multiple passes, everything was slightly looser than a single pass, with only 1 mortise now out of place, a side grain.

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[Dan Friedrichs]

Possible your fence or baseplate is not flat?

[George Yetka]

You are letting the bit do the cutting correct? My first mortise I cut I ended up pushing a little too hard and raised the domino of the work piece a bit. It made the mortise not square. afterwords I took my time and let the bit do the cutting.

[Jim Becker]

You are letting the bit do the cutting correct? My first mortise I cut I ended up pushing a little too hard and raised the domino of the work piece a bit. It made the mortise not square. afterwords I took my time and let the bit do the cutting.

This is good advice...I was "shoving it in" when I first got my DF700 but learned that slow and steady was a lot more accurate. Holding the fence down on the material securely, pushing from the back and letting the cutter have time to penetrate, cut and evacuate the chips make for the most consistent cutting. Side grain and end grain place different stresses on the cutter, too, so slow and steady also helps with that.

[mreza Salav]

Which domino model is it? 500 or 700? I've had both and proper holding/plunging technique can contribute to proper/improper fittings.
Whenever I want absolutely perfect (like zero error) joint I use doweling jigs (e.g when wanted to join 48" wide pieces of plywood to get 60" wide) but still with domino you should be able to get near perfect joints. Here are some of the things that can contribute to poor joint:
- plunging too fast, contributes to vibration (especially when doing end-grain, as it's more difficult to cut)
- pressure on the fence should be solid
- for plunging into very narrow boards (think end grain of a 2"x0.75" board) it's best to have a jig to hold the piece, sometimes I holed the piece against the fence with hand and actually plunge the piece/fence into the bit (instead of moving the machine).

[Jim Becker]

I'm going to add that the reason for the recommendations to gently push from the cord end of the Domino tool (regardless of which version) is that we can sometimes have a tendancy to slightly lift while "fully gripping" the tool. The same is true, honestly, with biscuit cutting machines, too, although there is often a little more wiggle room there because of the nature of the fastener. Domino tenons (and correspondingly dowels, too) that inadvertently have even a slight angle to the precisely fitted mortise can then produce a noticeable offset in material height of two pieces being joined. Care must be taken to insure that those mortises are cut without any up or down deflection because one's hand is physically exerting vertical pressure through the cut.

[ChrisA Edwards]

I think I had similar issues. I made myself a little clamping jig that attaches to the miter slot on my tablesaw.

I reference all my Domino cuts off the surface of my tables saw and the base of the 500, so the domino fence is not used for height setting. If I want my mortise a little higher on the side I put a spacer piece under the Domino base.

https://hosting.photobucket.com/images/i452/cedwards874/DominoClamp(1).jpg

[Warren Lake]

dont have a domino but have had a lamello forever. At one point I bought a second one as it was not accurate bang on and the second was just the same Questioned answered first one worn out., I never clamped stuff didnt have the time as some work was production stuff. Its not practical but I can see it eliminating some possible error in the handling aspect. I never used the shoe you put on just worked face side down off the base of the machine. IF I needed to change placement for some reason then just put a shim under the machine or the work being lamelloed. If I had tons to do and really needed then id get an air piston triggered a foot pedal, done that for other jigs and its fast good.

Error can be induced in different places. If I clamp the clamp hard on my mortise machine with a dial I can see I deflect it .003 to .005 so doing doors if too much force then the rail and style can be out of flush. Part of that is the design and had the clamp come off the back fence there would be no deflection.

[Bryan Hall]

Alright I think I may have identified the issue.

Domino 500.

The pin that holds the fence is sloppy the whole way across the machine. As a result, it doesn't consistently land at 90 degrees. It looks like 90, but I have to hold a square to it and clamp the fence in order to get it to perfect 90. It naturally goes to about 91 degrees if I don't back it up. I re-ran the test after clamping the fence with a square and sure enough, everything came out perfect.

Anyone else having to mess with this on theirs?

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[Prashun Patel]

not at ALL. It should not be sloppy. I would contact Festool. I suspect they may help you.

[Randy Heinemann]

No, there were no issues right out of the box for me. Everything was square and tight. I guess I probably have never checked the squareness of the fence but I've never had a problem either unless I've made the standard user mistakes - Domino resting on the table instead of the plate, not referncing the correct side of the board, sometimes plunging too fast, and not holding the tool securely enough so it moves while plunging. Otherwise, the result is generally perfect; so perfect, I rarely use anything but Domino loose tenon joints.

[Derek Cohen]

Alright I think I may have identified the issue.

Domino 500.

The pin that holds the fence is sloppy the whole way across the machine. As a result, it doesn't consistently land at 90 degrees. It looks like 90, but I have to hold a square to it and clamp the fence in order to get it to perfect 90. It naturally goes to about 91 degrees if I don't back it up. I re-ran the test after clamping the fence with a square and sure enough, everything came out perfect.

Anyone else having to mess with this on theirs?

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A work-around this would be to use the Seneca Domiplate.

https://toolsforworkingwood.com/prodimg/ms/big/MS-DOMIP_B_big.jpg

Regards from Perth

Derek

[Warren Lake]

why do that and use it upside down when you can just set it on the base like I do with the lamello. Never used it once the proper way.

[Derek Cohen]

why do that and use it upside down when you can just set it on the base like I do with the lamello. Never used it once the proper way.

Because you cannot always rest the machine on a flat surface in front of the workpiece.

Regards from Perth

Derek

[Dave Sabo]

Because you cannot always rest the machine on a flat surface in front of the workpiece.

Regards from Perth

Derek

Great if all you do is edge work. The second you want mortise a face , the plate becomes a liability and takes more time to remove.

To each , his own. Seneca has sold a lot of em.

[Phillip Mitchell]

Bryan,

Are you using proper dust extraction? Not sure if that has been addressed yet in this thread, but I could see that being a potential issue especially if plunging “aggressively”, causing the bit to deflect. Just a thought.

[Warren Lake]

dont get it, what you show working upside down, flip the panel and work off a table and the base of the machine. Ive never used a shoe on a lamello only worked from the bottom and it works great, it doesnt matter where. Im probably not understanding you and will re read it. I think they sort of work the same way though dont have one so would understand if I did.

[Randy Heinemann]

Any work around seems to ignore the core issue if the fence doesn't consistently sit at 90 degrees. There is something wrong with the Domino itself (unless there is some way of tightening that pin). All Festool tools have a 3-year warranty so, if the tool is less than 3 years old, send it in for warranty repairs. If not, then I guess it would be cheaper to use one of the work-arounds even though that wouldn't resolve the problem. Even if out of warranty it might be worthwhile to attempt to get a repair estimate. The tool allows me to design and build creative projects without giving thought to the difficulty of joinery.

I'm speaking for myself here, but it is one of several tools I just wouldn't do without regardless of price. It just has made my life easier and, in some cases, allowed me to do work I might not otherwise attempted. It's just worth it to make it work correctly.

[Steven Mehl]

Festool has a good basic video (https://www.youtube.com/watch?v=sD2QxrwuvJk) on using the dominio 500. I found for myself the most important thing was to make sure I was pushing down and forward tightly on the front handle and then pushing the bit in slowly. And of course like others have mentioned to make sure it is not sitting on bench rather than face. It may also be your bit is getting dull?

[Johnny Barr]

Great if all you do is edge work. The second you want mortise a face , the plate becomes a liability and takes more time to remove.

To each , his own. Seneca has sold a lot of em.

Yes Derek. I use the domiplate 99% of the time (so does Peter Millard on youtube) and love its accuracy. When mortising a face I just hold it vertically except if its in the middle of a board and yes you would then have to remove it (about 15 seconds) . I only use the fence when doing bevel joints. I found the fence locking system on mine isn't as rock solid as my old biscuit joiner or Mafelle's duo dowler for example. I think it is a viable alternative

As for the OP I wonder if you know another domino user and try theirs out.

[Randy Heinemann]

Alright I think I may have identified the issue.

Domino 500.

The pin that holds the fence is sloppy the whole way across the machine. As a result, it doesn't consistently land at 90 degrees. It looks like 90, but I have to hold a square to it and clamp the fence in order to get it to perfect 90. It naturally goes to about 91 degrees if I don't back it up. I re-ran the test after clamping the fence with a square and sure enough, everything came out perfect.

Anyone else having to mess with this on theirs?

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Are you sure it's not just that the lever used to secure the fence is loose. That is adjustable.

[Michael Drew]

I have the same issue as the OP, quite frequently. I've narrowed the problem down to - well, me. I get in a hurry and do not focus on ensuring the machine is registered to the piece correctly. When using the fence, it's critical to make sure the Domino face and the fence are square to the work piece. It doesn't take much of an upward or downward tilt of the tool to cause the mortice to be just slightly out of place to where you want it.

Using the base generally results in better mortice placement for me, but that technique doesn't always work out on some projects. I did buy the Seneca plates, and they do work well - for edge work only though.....

[Randy Heinemann]

At this point, i assume that the 3-year warranty has expired for the OP. If not, sending it to Festool service for warranty service would resolve any defective parts if they exist.

[Greg Quenneville]

Depends. If it is an obvious manufacturing defect they may repair it free. When I sent my Kapex in for an electrical recall they upgraded my fence no charge.

[Jim Dwight]

If the nut that secures the fence is tight it will not move. It is one of those nuts where you have to lift the plastic piece off the actual nut sometimes to get another bite on the nut. Is it possible the OP got one where the nut was kind of loose and didn't notice it? If you can move the fence even one degree the fence is not tight. I would make sure that nut is tight lifting the plastic piece as necessary to turn it as far as necessary. I am not suggest any sort of extreme or even heavy force. Just turning it by hand until it obviously stops. It also seems possible the nut is loose but seems tight due to damaged threads. I will say again just for emphasis, if the fence moves the nut that secures it is not tight.

This does not seem to be the issue but the ergonomics of the 500 seem weaker to me than the 700. The 700 has a large vertical hand hold for plunging that I think makes it easier to just plunge and not rock the machine. The 500 is like my old Skil biscuit joiner where you grab the motor. I use significantly more force on the fence than I do on the plunge for both tools. I had problems like the OP describes with my old Skil until I got this figured out. If I pushed harder than necessary with the plunge hand I found it easier to inadvertantly tilt the tool. Nice smooth pressure on the plunge something like pulling the trigger on a gun. Firm downward pressure on the fence.