Author Topic: Question for MT55cc owners  (Read 2095 times)

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Offline Svar

  • Posts: 2496
Question for MT55cc owners
« on: June 15, 2020, 05:49 PM »
Does anybody experience poor torque at lower speed settings on Mafell MT55cc? It's a 120V model.
I sometimes cut aluminum and acrylic, which require low speeds. MT55 bogs down on setting #2 in 3 mm acrylic [eek]. So, forget aluminum I guess.
It won't cross cut a 2x4 at speed #2 with 48 tooth blade. Not something you would normally do, but a test you could perform if you don't have scrap of acrylic lying around. I have not experienced this with TS saws.

And before you ask is your blade backwards, is your track twisted in a pretzel, etc. etc. etc. The answer is NO.
« Last Edit: June 15, 2020, 05:55 PM by Svar »

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Offline TwelvebyTwenty

  • Posts: 108
Re: Question for MT55cc owners
« Reply #1 on: June 15, 2020, 06:22 PM »
I have a Bosch GKT 55GCE which I think is the same motor as the MT55cc, given the Bosch tool is made by Mafell. I cut 8mm solid sheet polycarbonate at setting 3, so setting 2 for 3mm acrylic should logically not be a problem. I am UK based and so my machine is the 240v version - but I can't imagine that would make such a significant difference as to result in the problem you are describing in 3mm acrylic.

Offline Svar

  • Posts: 2496
Re: Question for MT55cc owners
« Reply #2 on: June 15, 2020, 06:39 PM »
I have a Bosch GKT 55GCE which I think is the same motor as the MT55cc, given the Bosch tool is made by Mafell. I cut 8mm solid sheet polycarbonate at setting 3, so setting 2 for 3mm acrylic should logically not be a problem. I am UK based and so my machine is the 240v version - but I can't imagine that would make such a significant difference as to result in the problem you are describing in 3mm acrylic.
Thank you. Does your GKT motor modulate (rev up and down) when you spin the blade with no load? This is considered to be "normal" on MT55 and according to a N. Am. dealer has to do with anti kickback technology. This is especially prominent on low settings.

Offline TwelvebyTwenty

  • Posts: 108
Re: Question for MT55cc owners
« Reply #3 on: June 15, 2020, 06:44 PM »
Not at no load - when I spin the saw up to speed before plunging it has a soft start and takes 1-2 seconds to reach full speed then sits at constant RPM. It does 'throttle back' and make a whine if the blade gets pinched during a long cut as a safety function given no riving knife - but certainly not at no load.

Edit: Although I never use setting 2 only setting 3 upwards - so it may be less prevalent. I can test tomorrow if nobody else can clarify by then.
« Last Edit: June 15, 2020, 06:51 PM by TwelvebyTwenty »

Offline Cheese

  • Posts: 9756
Re: Question for MT55cc owners
« Reply #4 on: June 15, 2020, 06:52 PM »
I need to pull out the MT55 tomorrow for a project. I’ll throw on the 48 tooth blade and give it the 2x4 test.

Offline Svar

  • Posts: 2496
Re: Question for MT55cc owners
« Reply #5 on: June 15, 2020, 07:02 PM »
Thank you, all. A test would be great.
Cheese, please, check if your MT55 modulates as mentioned above.

Here is a video (not mine):
« Last Edit: June 15, 2020, 07:11 PM by Svar »

Offline Jiggy Joiner

  • Posts: 1111
Re: Question for MT55cc owners
« Reply #6 on: June 15, 2020, 07:24 PM »
My TS55 used to hunt at idle but, once cutting it was a bit gutless
I sold mine eventually and bought a 36v Makita, and never looked back. I was cutting very wet 45mm thick pressure treated last Friday, no problem. My Mafell MT55 240v also glides through this sort of stuff.
« Last Edit: June 18, 2020, 09:08 AM by Jiggy Joiner »

Offline TwelvebyTwenty

  • Posts: 108
Re: Question for MT55cc owners
« Reply #7 on: June 16, 2020, 07:46 AM »
I tested with my Bosch TS this morning and it does indeed modulate a little at speed two, however it's not as pronounced as in the video above.

I don't have any 2x4 softwood lying around at the moment, but I did cut a piece of 8mm polycarbonate on speed 2 and at a sensible feed speed - it did not bog down.

Offline Cheese

  • Posts: 9756
Re: Question for MT55cc owners
« Reply #8 on: June 16, 2020, 10:12 AM »
Cheese, please, check if your MT55 modulates as mentioned above.

@Svar  I haven't given it the 2x4 test yet, just fired it up to give it a listen. Mine does NOT hunt like this video. As you reduce the speed the saw does make the same sound as the video however, after 1-2 seconds the speed stabilizes and the sound remains constant. If yours hunts like the video, I'd have Timberwolf take a look at it. I'll try the 2x4 test later in the day.

Offline Kraftt

  • Posts: 76
Re: Question for MT55cc owners
« Reply #9 on: June 16, 2020, 01:59 PM »
Thank you, all. A test would be great.
Cheese, please, check if your MT55 modulates as mentioned above.

Here is a video (not mine):


Not sure what that 2013 video was trying to convey?  You don't use the saw just idling it doing nothing.  The electronics that replace a riving knife in this specialized saw are designed / tuned to work with a certain amount of load applied in a range.  Just spinning the blade in free air has the circuit hunting because it's approaching a given range of detection.

If that guy did the same useless 'test' again without a blade installed I'm willing to bet he would have found that modulation disappeared because there's not enough info for the circuit to sense anything / engage.

Mine's a 2016 110v.  In my test I get very smooth 'idle' running throughout the speed wheel settings with perhaps the slightest detection of modulation at the lowest speed setting of #1.  Which would be the electronics doing exactly what they are supposed to do. Taking the blade out and running at idle through 6 - 1, it's smooth (even smoother) all the way through.

Never had issues cutting polycarbonate with it (trying many speeds for best results), cut cement board all the time with old dull blades, cut wet pressure treated occasionally and rip down green 2x4's as well - no issues.

What year is your saw?  Import or N.A.? 

 

Offline Svar

  • Posts: 2496
Re: Question for MT55cc owners
« Reply #10 on: June 16, 2020, 05:21 PM »
The electronics that replace a riving knife in this specialized saw are designed / tuned to work with a certain amount of load applied in a range.  Just spinning the blade in free air has the circuit hunting because it's approaching a given range of detection.
First of all, is the comment about hunting coming from Mafell tech support or is it your opinion?
One thing is clear. Some of these saws modulate through the entire speed range (and it's common) and others (particularly 240v) don't. One of this behavior is normal and the other is not. You can't have both. So, which one is it?

If that guy did the same useless 'test' again without a blade installed I'm willing to bet he would have found that modulation disappeared because there's not enough info for the circuit to sense anything / engage.
I checked. Modulation is the same blade on or off.

Bottom line, my controller might be faulty, given lack of torque on low speed. That's the reason I asked the question in the first place. Excessive lag in motor response and low torque might be related (i.e. the blade stalls before the motor is able to kick in). Upon some research I found out that aforementioned motor behavior is quite common, but not universal. I have 2014 unit bought gently used.
« Last Edit: June 16, 2020, 07:07 PM by Svar »

Offline Cheese

  • Posts: 9756
Re: Question for MT55cc owners
« Reply #11 on: June 16, 2020, 06:14 PM »
Here you go Svar...speed #2, 48 tooth blade, construction lumber. I wouldn’t use speed number 2 for this job but the saw cut fine. It maintained the set speed and just plowed on through.


Offline Svar

  • Posts: 2496
Re: Question for MT55cc owners
« Reply #12 on: June 16, 2020, 06:23 PM »
Thank you Cheese [not worthy], I'll be replacing the controller. Should be easy.
« Last Edit: June 16, 2020, 07:09 PM by Svar »

Offline Kraftt

  • Posts: 76
Re: Question for MT55cc owners
« Reply #13 on: June 17, 2020, 10:36 AM »
The electronics that replace a riving knife in this specialized saw are designed / tuned to work with a certain amount of load applied in a range.  Just spinning the blade in free air has the circuit hunting because it's approaching a given range of detection.
First of all, is the comment about hunting coming from Mafell tech support or is it your opinion?
One thing is clear. Some of these saws modulate through the entire speed range (and it's common) and others (particularly 240v) don't. One of this behavior is normal and the other is not. You can't have both. So, which one is it?

If that guy did the same useless 'test' again without a blade installed I'm willing to bet he would have found that modulation disappeared because there's not enough info for the circuit to sense anything / engage.
I checked. Modulation is the same blade on or off.

Bottom line, my controller might be faulty, given lack of torque on low speed. That's the reason I asked the question in the first place. Excessive lag in motor response and low torque might be related (i.e. the blade stalls before the motor is able to kick in). Upon some research I found out that aforementioned motor behavior is quite common, but not universal. I have 2014 unit bought gently used.


Where’s it coming from? It’s coming from the saw, if you had an undamaged one you could try it without a blade and hear for yourself.  But if your controller is faulty there wasn't much sense in 'checking' the difference was there? 
And why would you bother fixing the saw?  You’ve posted on and on for quite some time now on different forums how disappointed you are in the MT for numerous reasons.  In fact you seem to whine more than your saw.  This new issue only adds to your growing long list.
But it’s not new is it?  I remember you asked (and were answered) about this same exact thing on this forum, with same video reference, same answers, almost a year ago.
The other strange thing is that you say you bought this lightly abused used saw back in 2014, so you have owned it for what - 6 years?  You’re telling us you just now realized your saw couldn’t cut 3mm plastic?  If my saw suddenly couldn’t cut a thin sheet of plastic or a 2x4, when it could before, I wouldn’t be asking about modulation sounds I would definitely know something is wrong and send it in for repair asap.  Or maybe you meant to say that your used MT has always been this way? 
Btw - at the top you posted that your saw is a 120v, but you’ve previously posted that it’s a 110v UK version?  Could you tell us which is it? 

Maybe you could give it a rest and see if it fixes itself.

Offline Svar

  • Posts: 2496
Re: Question for MT55cc owners
« Reply #14 on: June 18, 2020, 01:07 AM »
Banana, ad hominem makes a lousy argument. Although I do whine a lot and will continue to do so. I've owned the tool for a bit over 8 month, but only now had a chance to use it. Please, re-read my earlier post.

Back to the facts. Modulation as in the video is not normal, contrary to the theory repeatedly told on MUF. It's ironic that I had to come to this forum to get calm and factual answers. Conclusion: in properly operating MT55cc motor response should be quick, just like in any other tool with electronic speed control. So, if anyone is experiencing similar (video), test it over a range of loads, it is likely due for repair.

Thank you all. Have a nice day!
Btw - at the top you posted that your saw is a 120v, but you’ve previously posted that it’s a 110v UK version?  Could you tell us which is it? Maybe you could give it a rest and see if it fixes itself.
Kolektor (speed controller). LOL!  [big grin]
« Last Edit: June 18, 2020, 11:23 AM by Svar »

Offline Cheese

  • Posts: 9756
Re: Question for MT55cc owners
« Reply #15 on: June 18, 2020, 08:43 AM »
FWIW Svar, I removed the 48 tooth blade and then stepped it through the 6 speed levels. The sound of the saw with the blade and without the blade was identical. It produced just a little less growling without the blade which makes sense since it had nothing to compensate for because I had removed the flywheel load.

Offline Jiggy Joiner

  • Posts: 1111
Re: Question for MT55cc owners
« Reply #16 on: June 18, 2020, 09:13 AM »
@Svar I’ve edited my earlier post as I got my wires crossed. My 240v MT55 hunts briefly at idle but, never during cutting, and it glides through pressure treated 4 x 2 just as my 36v Makita does.

My Festool 240v TS55 hunted at idle, and always seemed a bit gutless to me, I might have had a faulty saw though. I sold it, and was honest with the buyer, saying I found it underpowered and gave him like a 3 month warranty to be fair but, never heard from him again.

I love the MT55 and my next plunge saw will be the cordless version but, my favourite is the 36v Makita, for ease of use and power.

Offline JimH2

  • Posts: 1132
Re: Question for MT55cc owners
« Reply #17 on: June 18, 2020, 10:24 AM »
The 110V and 120V versions use the same motor, which is typical of power tools. I believe the same is true of 220V and 240V motors.

Offline Kraftt

  • Posts: 76
Re: Question for MT55cc owners
« Reply #18 on: June 18, 2020, 12:05 PM »
Banana, ad hominem makes a lousy argument. Although I do whine a lot and will continue to do so. I've owned the tool for a bit over 8 month, but only now had a chance to use it. Please, re-read my earlier post.

Back to the facts. Modulation as in the video is not normal, contrary to the theory repeatedly told on MUF. It's ironic that I had to come to this forum to get calm and factual answers. Conclusion: in properly operating MT55cc motor response should be quick, just like in any other tool with electronic speed control. So, if anyone is experiencing similar (video), test it over a range of loads, it is likely due for repair.

Thank you all. Have a nice day!
Btw - at the top you posted that your saw is a 120v, but you’ve previously posted that it’s a 110v UK version?  Could you tell us which is it? Maybe you could give it a rest and see if it fixes itself.
Kolektor (speed controller). LOL!  [big grin]
(Attachment Link)

So does any other logical fallacy - but we’re dealing with facts here supplied by you aren’t we.  And since you won’t let the saw speak for itself, instead using others videos, we’ll have to confine ‘trouble-shooting the problem’ with you.
 
No need to re-read your posts, once is enough, though you might want to take your own advice and note the question marks I use.

On a side note, since it takes the same effort to post an image either way why provide the wrong thing?  Here’s a pic of mine below showing the label location. Just blur any serial numbers if you need. Thanks.



Also here’s another video from 2013 of how the saw should sound, hope that helps.

 
« Last Edit: June 18, 2020, 01:00 PM by Banana »