Urgent help required! Domino trouble

[russ_1380]

HI

I'm having serious trouble with my new domino.

The material thickness scale is way out!  I have tried to adjust / calibrate it with no avail.

When I use the pre determined thickness stops, I read the scale and it is off by 1-2mm? ???

I have since calibrated it... by:

1.) Using the pre determined thickness stop
2.) Then adjusting the scale to suit half of this thickness.

All is well and dandy, but when I read the next thickness stop, its slightly off again.  The next stop further its even more off.  As I use the pre determined thickness stops, the higher up I go, the more out the scale is.

It works the other way too.  If I calibrate the thickness scale with the pre determined thickness stops; its not too bad for the first to stops, however as I move down the thickness stop scale, the error is magnified.  Leaving me out 1-2mm by the time I am on the lowest stop.

Please help!  I love this tool but have never had accurate results with it.  I think it may be a dodgy plastic thickness guide.

Any help appreciated!

 

[rnt80]

I'd give Festool service a call.  The service they provide is part of the high price tag, take advantage of it.

 

[russ_1380]

Cheers,

I'll ring them tomorrow.  Has anyone else had this problem?

 

[russ_1380]

In case anyone is interested....

I ran a search on here and found a good temp solution:

A genius on here worked out a way which I tired and it worked well.

1.) place domino machine on flat surface
2.) slacken off the material thickness fence
3.) measure the thickness of your mater, read the domino scale
4.) add 10 to this number, then divide the total by 2
5.) set your domino scale to this number

The result is the domino placed approximately in the centreline of the piece!  Well done whoever discovered it!  Thank you whoever found this out.

Anyway, I will eventually send the machine to festool to re calibrate it. Trouble is though, I'm using it too much at the mo, I need it every day and wouldn't be able to work without it. I'll wait a couple of weeks until I finish this job before i send it off.

Even with this problem, I still love it!  (can i get away with saying that on here  we 're all toolaholics)

 

[MCASE]

I love my Domino too and can sympathize.    I'm sure that Festool will take care of it.  But just for your convenience.  If your consistently using 3/4" stock you could file the 20 mm stop to exactly center it.  If you do not want to risk voiding  a warranty and hate the idea of messing with the tool you could also make a set of carefully milled thickness blocks that will preset  your fence to center on standard thicknesses i.e 3/4"  and nominal 3/4" for plywood.  Set the domino on a flat surface lower the fence to the top of the block and your good to go.  Hope it all works out soon.

 

[slb]

Please don't be offended, but the situation you describe seems so strange that I can't help wondering if you are confused?    I'm really puzzled because the plastic depth stop is a molded piece, not machined, and it is hard for me to imagine how it could be defective in the way you describe.  The depth scale should always read half of the setting on the plastic depth stop block, i.e. when you set the block to 20 the scale reads 10, when you set 26 the scale reads 13, and so on.  You aren't looking for a constant difference are you?  Again, I'm not trying to offend, just mind-boggled and hoping, maybe, to save you embarrassment if you send it for repair only to find out it is working as designed!

 

[russ_1380]

HI Steve

No Its ok, I didn't make it clear on my first post sorry.

Yeah i know that when using the stop, the scale should read half of the value printed on the stop.

The trouble I'm having is:

When I say use the 16 stop, the scale reads 8, as it should.

When I move along a couple of stops, say 25, instead of the scale reading 12.5, its reading about 13.5.

This error is exaggerated the further I go.  So when its on the 40 stop, it reads pretty much 22.

When I adjusted the scale (with the two pinch screws loosened).  I calibrated it so that the 40 stop read bob on 20 on the scale.  The same thing happened, the more stops I went along, the more the scale was out.  Again by about 1-1.5mm on the scale.

Surely for a ?500 tool this shouldn't be right?

I'll get the exact masurements that that scale if off, for you.  The above is from memory so may be out a lil.

 

[slb]

Hmm...if the scale is stretched that would do it, but that seems pretty far fetched.  Seems much more likely that the plastic depth stop isn't seating cleanly on the baseplate.  It doesn't look to me like that part of the baseplate is machined, just cast, and the depth stop is molded plastic.  But maybe there is a little chunk of stray plastic or aluminum from the castings that is jacking the depth stop crooked, or maybe one of them is warped.  That should be pretty obvious if you look.  A little chunk of stuff you could clean off and save yourself the return for repairs.  But, as you say, one would think something like that would be caught by quality control!

 

[russ_1380]

Cheers Steve.

I will look to see if I can strip that part and inspect without damaging anything.

Like you say, I really need the tool at the mo so can't send it off.

Mind you, using that technique of measuring, adding 10 and dividing by 2 is working just as well for now.  As long as I get the 'face up' side of the work piece correct when drilling with the domino it doesn't matter if the domino hole is slightly off centre.

I'll keep you posted if I find anything

Cheers

Russ

 

[richard.selwyn]

Just a thought when lining up the Domino for different thicknesses - I just bought a 2mm plate to clip onto the fence of my Lamello biscuit joiner - its great for centering the machine on thinner stock. (the fence is not as clever as on the Domino)  I find moving the Domino fence up and down a bit fiddly as I struggle to clearly read the mm increments.  Locking the domino fence in one position and then adding different shaped spacers would speed thinks up for me.

 

[russ_1380]

Richard, I agree

It helps to have 3 hands  ;D

TBH the rule above which I'm using is good enough for me.  As a beginner accuracy is only as good as I can get, rather than the machine is the limiting factor. 

I also find as long as I keep pieces 'face up' or 'face down' when drilling/dominoing it all lines up somehow!  I must admit I do struggle working out which pieces are face up and face down though.  ???  I think with practice I'll get better.

As an update, I will ring Festool to see what they say about the misaligned scale, however as I use the tool a lot I would miss it if it was away for servicing.

 

[ezdrive]

This one kept me up last night.  A festool with an inaccurate scale!  I decided to get all of my Festools out and put them to the Digital Micrometer Test.  The results were very good.  My TS75 Plunge saw was accurate within 1/4mm (whatever that is, i think 0.25mm).  Router, no problem and Kapex no problem.  Now the Domino, real problem...so I thought.  First, the height of the bit is determined by a nylon or plastic sliding notched scale.  If you set this scale to "40"  or 40mm, it is very obvious that this is not 40mm from the plate bottom to the bottom of the Domino Fence.  Wait, that is wrong...this is the measure from the center of the bit!  Now that I check it, it is relatively accurate.

Now for the depth...OK this is not accurate.  Based on the design of the measured stops, I believe this is intended to be for quick settings of individual Domino tenons only.  This scale is not to accurately set depth for any other purpose.

So, I am not sure what the problem is here.  I am not a professional craftsmen, but I never trust scales on any tool.  I always use the tool's scale and than check for accuracy with a known measuring tool.  When I am making panel doors, I cannot possibly trust the scale on my router or router table to duplicate the setting on Stile and Rail cutting bits!  I must measure with a micrometer.

I guess I do not understand the problem here.  I plan to review all of the setting on the Domino with a micrometer and tabulate the results.  Maybe then I will see the issue discussed here.

I mean no disrespect to any member here, but I take comments from Festool users very seriously.  When I here something negative, I want to check it out.  It has been the feedback that I received from this forum that I used to spend a big dollars on Festool products.  To date, I have no regrets about my purchase of any of the tools.  They have met or exceeded my expectations. 

 

[ezdrive]

I forgot to add this excellent instruction manual on the Domino.  It is worth the time to read.

www.festoolusa.com/.../Getting_the_most_from_the_Festool_Domino_Machine.pdf

 

[Jesse Cloud]

I noticed the extra depth, too, thought it was just to ensure some space for glue...

BTW, the Domino manual on the Festool web page shows a great technique for using a bit of pvc pipe to limit the depth of cut to whatever you want, so if the depth is critical, there's a easy workaround.

 

[Todd]

This threw me a bit however I don?t think the plastic stops are intended as a material thickness gauge but sets the distance the center of the cutter will be, referenced down from the top surface, divided by two. Set at 36 the cutter will be centered 18mm from the top surface. If you measure the distance from the base of the tool to the to the plate it will be
18mm + 10mm, (distance the center of the cutter to the bottom base) = 28mm. When I removed the plastic block and measured the steps they were an average of ?0.5mm short which would give an error of +0.25mm. For other than the set depths the linear scale on the side can be used then check by measuring the distance from the top plate to the top of the reference pin +2.5mm. If I set the block at 40 the scale reads right on 20 and at 20 it reads 10.

 

[RogerF]

Russ_1380
I can't explain the measuring discrepancy between the vertical stops and the scale. I have never paid any attention to the correlation between the two and I think the reason is you and I are using the machine with different techniques.
If I comprehend you properly I think you are trying to cut the mortise exactly on center. That way you will have perfect alignment no matter which facet is mated together. You say you struggle to know which face is up and which is down. May I respectfully suggest that that you not try to use this technique in any of your wood working tasks. No matter how accurate any given machine's scale is, you are introducing opportunities for error, whether it's the scale or your ability to read it accurately.
Far better to mark faces and ensure they are all facing up when applying the tool. In the domino's case I measure the the thickness of the stock and choose the closest number on the stepped scale. It will align perfectly every time so long as you know which face you're looking at. It just has to be close to center, not right on it. Better, perhaps, to be able to tell by looking at the cut and know which side is up.
The only time I will use the scale is when it's important to get the cut centered like when you are attaching 3/4" slats to a 1 and 1/2" rail for example. Even then I will mark all faces to ensure a consistent alignment. I assume there will be error, even if it's not apparent to the naked eye, but the error will be consistent.
Check your fence height during operations to make sure it hasn't slipped.
3/4" stock can be cut with the fence folded up and with the base flat on the work bench next to the stock. However, you must be sure that the stock is flat against the bench. If there is any bow to it you must clamp it down or resort to the fence. Again, mark your faces!

 

[slb]

I always mark the reference face of all pieces before cutting Domino slots in them.  As others have noted, that assures that the surfaces line up regardless of the Domino's scale.  Since I usually make pencil marks and align to them via the plastic scale in the fence or the scribes in the bottom of the base, marking the reference face isn't any extra effort.  When joining the end of one board to the middle of another, I usually clamp the end board onto the other board at the required location and reference from the bottom of the Domino to the face of one board and the end of the other.  As Roger notes, I have on occasion gotten bad alignment from this technique if the end-jointed board is cupped across its width.

But I don't think that's what puzzled the OP.  As also noted by several people, the metal scale *should* always read 1/2 of what you set on the plastic stop.  A small, consistent offset wouldn't be surprising, and you can reposition the metal scale if you want to calibrate it.  But the OP was seeing a difference of several mm after he adjusted for a match to 1/2 at a particular setting.  That's what has several of us scratching our heads, as it doesn't seem possible!