Domino mortise not horizontal: Problem solved?

[Brice Burrell]

I had an exchange of e-mail with a member that had misaligned mortises, not horizontal, with his Domino. See this thread for a rundown of the problem, Domino mortices not horizontal.Anyone seen this before?I still love the thing!
My advice was to call Festool's service dept; the tech told he might be plunging the his Domino too slowly and this may have caused the misalignment. A document to help users produce better results with their Domino had been put together by Festool with common problems users have and the solutions to these problems. A chart is in this document with the proper feed rates for each size tenon and depths. With the new feed rate this member's problem was corrected. This may not solve everyone's problem, but I suspect for many people this is the solution. Here is the document in PDF format, covered are some common user problems related to plunge/feed rate.

 

[Mark Carlson]

I have to admit I don't  understand why the speed of the plunge would make any difference in the alignment, depth or width. 

 

[Les]

Very interesting. I know people will have a hard time believing how much the feed rate can affect the location, but I sure have experienced it.

When I cut the 10mm mortises 90 times, I started counting how long it was taking to feed. Eight seconds was the magic number. Who would have thought I was feeding at the rate they would recommend?

 

[Brice Burrell]

I have to admit I don't  understand why the speed of the plunge would make any difference in the alignment, depth or width. 

It's true, the feed rate makes a big difference. Most mortises that I've had trouble with can be attributed to feed rate error (read user error).

I forgot I had a copy of this document since April, I also completely forgot about the horizontal misalignment can be attributed to feed rate error. If I remembered I had this info sooner it might have saved some people a little aggravation, sorry about that. I hope those of you with the problem try out the recommenced feed and report back with the results.

 

[sainttjames]

Yesterday I tested my domino after reading the other thread and what I discovered concerned me. I plunged 8 mortises in as nearly a consistent manner as I could muster and every single one of them sloped from upper left to lower right...very consistent too  the right side of the mortise averaged about 0.20mm lower than the left side...

After looking at the document back to the shop I went...first 4 mortises I plunged (at a significantly faster speed than I was accustomed from previous plunging) the differences decreased substantially (all

 

[Jimhart]

I have to admit I don't  understand why the speed of the plunge would make any difference in the alignment, depth or width. 

Mark,

Do you sometimes vary the feedrate with a drill, jigsaw, tablesaw or router? Seems logical this could have some of the same dynamics.

Jim

 

[vteknical]

Perhaps Festool should sell a Metronome to help with this. You simply input the type of wood, plunge depth, bit diameter and and bit sharpness level, instantly provides your timing info.  ;D 

 

[Mark Carlson]

Good point, I do. 

Its the misalignment if you go to slow that doesn't make sense to me.  I would expect deflection in the bit if I go to fast.  I would expect burning by going to slow but misalignment?  Note:  I'm not having issues with my domino mortises.  My plunge speed seems to work fine.  I will do some extra slow plunges to see what happens.

~mark

I have to admit I don't  understand why the speed of the plunge would make any difference in the alignment, depth or width. 

Mark,

Do you sometimes vary the feedrate with a drill, jigsaw, tablesaw or router? Seems logical this could have some of the same dynamics.

Jim

 

[csmark]

Thanks a ton!  I know I wasn't anywhere close to these times.  I was either too fast or slow and saw both results.

C. S. Mark