Domino XL alignment problems

[Gixxerjoe04]

Working on a crib for my first kid which he's due to arrive in 5 weeks, which will be put together with my domino, hopefully.  Got everything ready to go and was going to start making all the mortises tonight and decided to make a few test cuts just to make sure everything was good.  With my luck and time crunch, everything isn't alright.  Did some test cuts and put them together and noticed the pieces weren't flush, tried a couple more and same result.  I had put on the domniplate since the slats are pretty thin and without it, the dominos wouldn't be centered.  Thinking that might be the problem, I took it off and tried again with the same result.  My tests pieces and the slats are pretty narrow, so I decided to try on some wide plywood and got the same results.  Not sure what to do, tried looking online and couldn't find what I was looking for.  On a spare slat I cut, testing it to see if it were flush, was off .5mm on the ends which doesn't seem like much, but it is.  Also worried if it's off that much on a small piece, would be worse on wider stock and would cause more problems using multiple tenons.  I have the work pieces secured where they can't move when plunging, and trying probably 10 pieces, all were messed up.  Tried pushing down harder on the fence thinking it's user error but had the same result.  Any ideas or suggestions?

 

[Nat X]

That looks very slightly twisted more so than not flush. Dominos are wood and will swell and contract just like everything else. If you sand them down slightly can you get it aligned better?

 

[Shane Holland]

Common causes for this sort of result are not using dust extraction and plunging too fast.

 

[Birdhunter]

Is there just one domino joining the boards?

 

[Gixxerjoe04]

You can look at the mortise and see it's off, so not the result of a swollen tenon.  I don't have a dust extractor but use my shop vac with the hose from rockler and it works well and pulling everything out and I don't plunge very quickly.

 

[Gixxerjoe04]

Is there just one domino joining the boards?

The pic is just one, but I got some plywood and put 2 in each side separated by around 4 inches, got the same result.

 

[Nat X]

Assuming you're referencing the same surfaces for each cut, alignment errors in the cutter or the fence, though unlikely, should be identical and irrelevant. Without watching you do it, the absence of any kind of mark on the boards would have me guessing that you're flipping them over.

 

[Shane Holland]

Ok, another thing to check is to inspect the cutter for damage.

 

[Gixxerjoe04]

Some of the test pieces I marked them, some I didn't but I know I didn't flip the boards, still shouldn't be crooked like the way it is.  Will try to set my phone up tomorrow and film me doing it and maybe you all can see if I'm doing something wrong.  Will check the cutter too but haven't got to use my domino much since I got it, only have done 120 or so mortises with my 6mm bit into white oak but would assume that's nothing for the bits.  Here's a pic of a couple test pieces, might not be able to see the difference from the pic, a lot more noticeable in person.

 

[Bohdan]

In the photos there is definitely something wrong with the start of the plunge that suggests that you are not holding the domino correctly and it is moving while you plunge.

Show us how you are doing it.

 

[Gixxerjoe04]

Will try some better technique tomorrow and see if that helps, if not I'll film myself doing it.  The piece of maple in the first pic was secured really well but the cherry piece, probably not as good which probably didn't help.  Was kind of freaking out, finally got time to work on it and this happened. 

 

[thudchkr]

It kind of looks like you're plunging too far for the cutter. If that is so, it could cause what looks like a slight flare at the top of the mortise. Again conjecture, but if that happened, the cutter might then try to climb the end of the mortise, resulting in a twisting.

I'm basing all this on what looks like a flaring of the top of the mortise, and that plunging the cutter too far is the culprit. You said you're using a 6mm cutter and a Domino XL.  Evidently you're using the Seneca adapter, or something similar.

If nothing else, try decreasing your mortise depth to see if that results in a straight mortise.

Good luck

Clint

 

[Nat X]

That entrance wound is about what I'd expect to see if I re-plunged the same hole 4 or 5 times because of a mistake. If you're getting that in one shot, there's no way the cutter is sitting still on the workpiece.

 

[Gixxerjoe04]

Only going 20mm into the wood, so that shouldn't be a problem.  The last time I used my domino was probably 4 months ago before I had to move all my equipment into storage.  6mm was the last bit I used and was still on there, might check and make sure it's still snug on there.  Probably doesn't help mortising in stock that isn't wide and not using the repeating tool, but can't use it with the domniplate. 

 

[clark_fork]

Set the XL on a flat surface and make sure the plate is flat-on and face is clean.

Check the angle setting with a dead-on engineering square and make sure the angle locking lever is secure.

Check to make sure you are cutting into square stock.

Check the spacer pins and make sure they are not sticking and move in and out freely.

Clamp a fence on top of the piece and check to make sure it is square. That way you can tell if there is sideways drift.

Go as deep as you need to into the mortise. Don't over cut the depth of the mortise.

 

[Gixxerjoe04]

Had my wife film me using my domino tonight, not the best filming job but hopefully it'll help.  Turn the sound off, use my shop vac for dust extraction.  Checked the 6mm bit on the adapter, was tight, changed the bit to an XL 8mm bit for the filming and to see if it was off and it was. 

 

[Gixxerjoe04]

So, guess I'm an idiot for not checking in the first place, the fence....  Thought I was over tightening the fence, so I loosened it and set it to 90 and lightly tightened it down and put my straight edge to it.  The left side is nice and flush, right side, not so much.  Can rock my straight edge, so found the problem, now gotta get it fixed.  Wood milled to final thickness and baby getting closer to popping out, lets add some more stress to the situation [tongue] You might be able to see the gap in the pic.

 

[ear3]

Glad you identified the problem.  Sometimes it just takes us getting conscious about our own processes in an attempt to explain it to others to pinpoint the issue.  That's why the FOG is here.

 

[grconnors]

Sorry to dig an old post but did this end up getting resolved?

 

[Gregor]

Sorry to dig an old post but did this end up getting resolved?

Was solved with a trip through the Festool service department, if I read the topic correctly.

Do you have a problem with your machine?