TS55-REQ and MFT-3 Not Cutting Square

tjbnwi said:
How to perform a 5 cut test;

Use a piece of plywood about 2' square, number the 4 sides, place edge #4 against the fence with edge #1 under the rail, cut off about 1/8", rotate #1 to the fence, cut 1/8" off edge #2, rotate 2 to fence, cut 1/8" off edge #3, rotate #3 to fence, cut 1/8" off edge #4, rotate edge #4 to fence, this time cut off about 3/4" off edge #1, mark the fence end of the cut prior to picking the piece up. Measure each end of the piece with a caliper or micrometer.

The difference from end to end is 4 times how out of square the MFT or saw is.

[member=4105]tjbnwi[/member] , I would like to try this test but have a question.  When you say to start with a piece of plywood "about 2' square", does it need to be truly square at the start?  Thanks.
 
I hope that this helps explain the 5 cut (often called 4 cut) test.

Here is a video demonstration to prove the accuracy of the PGS:


The starting size was about 420 mm square.

Peter
 
Peter Parfitt said:
I hope that this helps explain the 5 cut (often called 4 cut) test.

Here is a video demonstration to prove the accuracy of the PGS:


The starting size was about 420 mm square.

Peter


Very helpful Peter.  Thanks!
 
crookedcutter said:
2 – I put the track supports back on the table, entering the rails from the left side of the table, pushed them as hard as I could against the factory-installed stops, and tightened them down very tight.

The factory installed stops inside the slots were off on my new MFT, so using them unchecked as a reference for the rail you might introduce the error you get.

What I did was to setup the back fence, then align the fold-down rail (with the factory-installed stops removed) using a known good square to be rectangular to the fence, then reinstall the stops into the slots at the now known-good position.
Now I can tear apart my MFT for moving and when putting it back together I can align the rail holders against the stops with the confidence of knowing to get a square cut without further checking.

PS: I use two 495541 to attach the back fence.
 
Gregor said:
The factory installed stops inside the slots were off on my new MFT, so using them unchecked as a reference for the rail you might introduce the error you get.

What I did was to setup the back fence, then align the fold-down rail (with the factory-installed stops removed) using a known good square to be rectangular to the fence, then reinstall the stops into the slots at the now known-good position.
Now I can tear apart my MFT for moving and when putting it back together I can align the rail holders against the stops with the confidence of knowing to get a square cut without further checking.

PS: I use two 495541 to attach the back fence.

My MFT3 also was not square from the factory.  I used the same technique that you described and reset the factory stops which squared it up.  I then used dogs and a pair of the 495541 fence clamps to hold the rear fence and register it to a pair of parf/veritas dogs, but the fence didn't hold tight enough if it was hit, so I went back to the protractor and one fence clamp.  I made a MDF square for quick checks and now I get consistent results.  Panels are now dead on square when measured across opposing diagonals.
 
Gregor said:
The factory installed stops inside the slots were off on my new MFT, so using them unchecked as a reference for the rail you might introduce the error you get.

What I did was to setup the back fence, then align the fold-down rail (with the factory-installed stops removed) using a known good square to be rectangular to the fence, then reinstall the stops into the slots at the now known-good position.
Now I can tear apart my MFT for moving and when putting it back together I can align the rail holders against the stops with the confidence of knowing to get a square cut without further checking.

PS: I use two 495541 to attach the back fence.

Dick Mahany said:
My MFT3 also was not square from the factory.  I used the same technique that you described and reset the factory stops which squared it up.  I then used dogs and a pair of the 495541 fence clamps to hold the rear fence and register it to a pair of parf/veritas dogs, but the fence didn't hold tight enough if it was hit, so I went back to the protractor and one fence clamp.  I made a MDF square for quick checks and now I get consistent results.  Panels are now dead on square when measured across opposing diagonals.

[member=53905]Gregor[/member] , I had your same experience with the two fence clamps as a replacement for the protractor head.  They did not hold the fence well enough.  Hoping to get this figured out soon though.
 
Patrick Cox said:
tjbnwi said:
How to perform a 5 cut test;

Use a piece of plywood about 2' square, number the 4 sides, place edge #4 against the fence with edge #1 under the rail, cut off about 1/8", rotate #1 to the fence, cut 1/8" off edge #2, rotate 2 to fence, cut 1/8" off edge #3, rotate #3 to fence, cut 1/8" off edge #4, rotate edge #4 to fence, this time cut off about 3/4" off edge #1, mark the fence end of the cut prior to picking the piece up. Measure each end of the piece with a caliper or micrometer.

The difference from end to end is 4 times how out of square the MFT or saw is.

[member=4105]tjbnwi[/member] , I would like to try this test but have a question.  When you say to start with a piece of plywood "about 2' square", does it need to be truly square at the start?  Thanks.

No, the piece does not need to be square, just 1 straight side. Once you are done with adjustments the piece will be square.

The larger the piece the better to start. Gives you more attempts to get things right.

Tom
 
Just one more input. I've never put much trust in the MFT protractor. It's been hung on the wall since I bought QWAS dogs.

I square the track saw guide using QWAS dogs and  Woodpecker framing square. I do use a SlopStop.

I verified the square's trueness using the draw a line, flip the square, and draw another line. Next, I checked the MFT squareness using the QWAS dogs and the big square. Next, I set the guide rail square using QWAS dogs and the big square.

When I make a cut, the top edge of the wood is pushed up against several QWAS dogs and clamped to the MFT.

I make the first cut "fat" so I can check for trueness.

I always check the first cut using a verified square to be sure everything is true.

If the first cut is true, I cut for effect.
 
Patrick Cox said:
[member=53905]Gregor[/member] , I had your same experience with the two fence clamps as a replacement for the protractor head.  They did not hold the fence well enough.  Hoping to get this figured out soon though.

My point was: The initial positioning of the two factory installed stoppers (item#4 acticle#437377 in the festool EKAT for MFT/3, one each in the long extrusions, used for registering the holders of the folding rail against them) were off on my table, leading to the rail being off >1mm (at least on mine) over the depth of the table, on initial assembly of the table.

So my suggesting was to get a repeatable back-fence position, then (and only once) align the rail to it and after that install the stoppers against the now-correctly positioned rail holders. Doing it that way I obtained a setup that is guaranteed to be square, even after the table has been disassembled for transport.

When using the MFT for square cuts I register the back fence against two 495541 (both put into the back extrusion), tighten them, then tighten the protractor - this makes the fence parallel to the back extrusion / the holes in the top, stable against forces applied to it and square to the now adjusted folding down rail. So the protractor is used by me only for stability (not alignment) in my setup. You can also register the back fence against bench dogs or in whatever way you see fit, as long as you can repeat the process without introducing an error.

Since the OP has as second part of his assembly list the 'register rail holders hard against the factory installed stops' my guess is these are off in his table. So my suggestion is: Just make sure that should you install the rail holders by registering them against the factory installed stoppers (in the extrusion slot) that these are actually aligned and not in some (more or less) random positions.
 
Something to consider when transporting or moving an MFT, if the top is not a very tight fit in the aluminium frame, and the MFT is bumped or knocked on one corner the MFT frame will rack slightly. This will alter the relative position of the factory stops and require you to realign them to achieve a square cut.

This could be the reason many find that their MFT will not maintain a square cut setting.

It could also be the reason why so many find that their factory stops have aparently changed position.
 
Here is a video that some may find useful regarding the 5 cut method.  You only need to watch the first 1/3 or so of the video.  It details the math of this concept a bit more...
 
This rocks. Was looking for something like this. No I can measure and check my own MFT/3
 
Here is the link for the video which was done by Festool instructors at one of their classes. It only requires that you have a reliable 90 degree square. Before making final crosscuts on a specific project, I always check with my square and, if off even just a tiny bit, I use this process. It only takes a few minutes but the reward is an accurate 90. The Festool classes I've had have always included one setup of the protractor, fence, and guiderail. This is the process that used.

I do also have the Slop Stop installed. The eliminates any play in guide rail slot underneath.

                   

It's my understanding that stops, as set at the factory are not there because they will be a perfect 90 and you can move those if needed. However, with the above method you don't need to.

For setting the fence square to the rail, the protractor would never be the cause of inaccuracies. Since I don't change the angles a lot and about 99% of my cuts are 90 degrees, I don't have any experience as to the accuracy of the protractor at 45 degrees or any other angle. I find the fence, protractor, and rail an excellent way to get "perfect" 90 degree cuts or for running my OF1400 on the rail for a dado on smaller boards.

 
Well after reading all this and having many of the same issues with the MFT/3 its beginning to look as if the protractor and fence system is a bust! one minute the fence is square next minute its out!...ridiculous!! I guess its adequate if your cutting studs for a house or a less forgiving project....but to start cutting up some beautiful hardwood only to have it not cut square is very disappointing....I think the QWAS dogs is the way to go and ditch the fence and protractor....maybe Festool will buy those parts back! HA!
 
rand17 said:
Well after reading all this and having many of the same issues with the MFT/3 its beginning to look as if the protractor and fence system is a bust! one minute the fence is square next minute its out!...ridiculous!! I guess its adequate if your cutting studs for a house or a less forgiving project....but to start cutting up some beautiful hardwood only to have it not cut square is very disappointing....I think the QWAS dogs is the way to go and ditch the fence and protractor....maybe Festool will buy those parts back! HA!

Once I got a square I trust, I found the MFT with the fence setup gives me the squarest cuts I've ever had with any tool. I'm not sure I understand why having to periodically check the squareness of the fence is any different than the setup and periodic checks I would do with any tools that requires either essentially perfect squareness or accuracy.
I periodically check all tools for accuracy and squareness where appropriate. This is especially true if I find the performance is not exactly what I expect. Bandsaw guides need to be adjusted once in awhile and always when installing a new blade. All tools need to be maintained to some degree. It is the rare tool that I would assume would always be as precise, square, and accurate as the day I first checked it and started using it. To me, the check of squareness of the fence to the guide rail I do just before making final crosscuts on the MFT is just part of setup and being sure I'm getting what I want in the end.
 
So....I took off the protractor and set it outside!... I took the rear fence up against 2 dawgs and clamped....then squared the rail off to another set of perpendicular dawgs.... did the 4 cut test and was a strong 2mm off north to south on my 4th cut piece... any ideas??
 
rand17 said:
So....I took off the protractor and set it outside!... I took the rear fence up against 2 dawgs and clamped....then squared the rail off to another set of perpendicular dawgs.... did the 4 cut test and was a strong 2mm off north to south on my 4th cut piece... any ideas??

If I understand the 4-cut (thought it was the 5-cut) method, the 2mm off would be 4X's the amount off on each cut. If that is correct your cuts would be 0.5 mm out of square or about 1/64" off. I would say you should be able to get closer than that, but whether that is accurate enough would depend on what type of finished products you are making. Assembling things square usually requires some part adjustment anyway. I don't believe that my cuts would even be 1/128" out of square using a known square to get the fence 90 degrees to the rail.

Some dogs fit into the holes a little loose which would definitely affect your square cuts. Others who have used various types of dogs for this may post to tell you which ones are the best. I have always had great luck on fit into the holes with the Parf Dogs. I would also guess that, over time, if you use dogs regularly, the most used holes would wear and not fit the dogs as well.
 
Thanks for your input... yeah .05mm is about right sometime a little more.....I guess thats the million dollar question is that about as accurate as its going to get???? or are we asking to much??.....as far as projects....well tables...cabinets,ect..thats what I am planing on... and prior to getting the MFT/3 I debated going with either the MFT/3 or a table saw.... just seemed the MFT/3 was a little more versatile...
 
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