Help diagnose tracksaw problem

[Derek Cohen]

Last weekend a friend came around for help in building a cabinet for a bathroom. The top is a 2" thick Jarrah slab with a live edge. Sawing the ends was a task for my tracksaw, and I set this up and made a few cuts. They were rough and really poor. I have never seen this before. The last time I used this tracksaw was about a month ago, and it produced clean and defined saw cuts. Also, as I recall, the kerf was narrower in the past. This suggested to me that either the blade was loose or damaged. I looked for these and could not find any evidence.


The tracksaw is a 20-year old Festool AT65E, which is in truly excellent condition. I purchased it about 18 months ago, and it looked like it had minimal use. The blade is almost new (one I replaced). Now I do recall cleaning the saw and taking a cut about a month ago, and the blade being slightly loose, and it rubbed against the chassis. I tightened it, used it, and all appeared well. That is the only possible "bump" I can think of.


I took the saw in to a Festool agent this week, explained the situation, and collected the saw yesterday. They said that they could not find any problems. I had questioned whether the arbor was loose or whether a bearing was worn, and they said there was no evidence of either. Today I took some cuts, and the problem was still there. Here are the cuts in Jarrah and some other hardwood ...








The interesting thing is that the cuts are clean at the offcut side ...





I do have another blade, brand new and unused, which came with the saw. This is cheapish and thin-kerf, but the same size and number of teeth. Here are the cuts (burning evident) ...





Here is the saw blade ...





Close up of the size ...





Finally, there is the track itself. This is a Makita, but the fit is good, all appears straight and clean, and unlikely to be affecting the result.


Okay friends, what are your diagnoses and recommendations?


Regards from Perth


Derek

[Andrew Hughes]

I’ll take a first guess having lots of experience with circular saws. Your saws blade is not cutting parallel with the tracks guidance.
Have you tried a test cut without the saw in the track?

[Derek Cohen]

Andrew, thanks. I tried that and it was no different.

Regards from Perth

Derek

[Derek Cohen]

SOLVED!!!

I was convinced by now it was the blade. Taking a closer look at the teeth ... can you spot it?



In case you are blind as a bat ....



I tapped the blade back into position - I probably should be looking at a new blade, but thought that this would be the best way to check that this was the culprit. So ...

Fresh cut off, and look at the MDF kerf ...





Regards from Perh

Derek

[Lee Schierer]

I would recommend replacing that blade as soon as possible. That tooth may come off. I would also look at how the saw is stored between cuts to insure another blade doesn't get damaged.

[Patty Hann]

SOLVED!!!

I was convinced by now it was the blade. Taking a closer look at the teeth ... can you spot it?



In case you are blind as a bat ....



I tapped the blade back into position - I probably should be looking at a new blade, but thought that this would be the best way to check that this was the culprit. So ...

Fresh cut off, and look at the MDF kerf ...





Regards from Perh

Derek

How would something like that happen? Just curious....
I have the Makita track saw with festool tracks ( just the reverse of what you have )

[Derek Cohen]

I mentioned this at the start. On a recent occasion, the blade had not been fully tightened down, the blade wobbled, but power was stopped as soon as I heard the sound of the blade scraping the aluminium chassis. But later (I recall, perhaps inaccurately) the saw was later used to cut Rock Maple successfully. That is the only explanation I can give.




Regards from Perth

Derek

[Derek Cohen]

I would recommend replacing that blade as soon as possible. That tooth may come off. I would also look at how the saw is stored between cuts to insure another blade doesn't get damaged.

Lee, a new blade has been ordered. The tooth on this blade looks fine. I used a drift pin to bend it back, hitting the body and not the carbide. This is some solid steel. Makes you wonder how it bent in the first place. This does not occur by placing the saw (which retracts) on something. I'll keep this blade as a back up ... may grind off the tooth to be safe.

Regards from Perth

Derek

[Jim Becker]

Funny thing is that the first thing that popped into my head was "bad tooth"...sho-nuf!

[Michael Burnside]

That exact same thing happened to me with my miter saw. No idea what I hit, but it bent a tooth. Good lesson though. Like me, I bet in the future the first thing you’ll do is check all teeth to diagnose any future problems

[John Kananis]

This also happened to my miter saw and it's the reason there's a forrest chopmaster in a (relatively spreading) rough cut tool - I'm not really looking for accuracy or a perfect cut from that saw but I do want consistency and a well-cutting blade that will give me a good (potential) reference point for other cuts, etc.

I'm glad you found the culprit.

[Andrew Hughes]

I would never guessed a bent tooth.
Starting the saw up against Jarrah is that what caused it?

[Patty Hann]

That exact same thing happened to me with my miter saw. No idea what I hit, but it bent a tooth. Good lesson though. Like me, I bet in the future the first thing you’ll do is check all teeth to diagnose any future problems

Is that all that happened? A bad cut?
(This was in class a few years ago): I was making a cut on a large dowel (2" diameter), on a 12" miter saw. I set it in a V block, started the cut and there was a sound like rifle shot.
The off cut (about 3 " long) was nowhere to be seen.

It turned up on the floor about 15ft behind me, pretty chewed up.
The instructor was suddenly right next to me (he must have teleported) and asked what I did.
I told him, including the part where he told me to use a V block.
So he took the dowel, marked off 3" , set it in the V block and BANG! same thing.

Later he told me examined the blade and that "it was bent".
I didn't think to ask him what specifically was bent.

[Derek Cohen]

I would never guessed a bent tooth.
Starting the saw up against Jarrah is that what caused it?

Andrew, here is another photo I should have presented and commented on. Pretty important in my opinion (just tha I found the culprit and forgot). What you see below is a photo of a kerf in mdf taken after the poor saw performance was evident ...



Of note, there are two kerf lines rather than one. That was what made me think that there was a problem with the blade being held securely. It looked like it was moving. Then I realised that a problem with the bearing or arbor would cause a sweeping action, which would cause a curved kerf. A bent blade would create a pattern with some wavy. A bent tooth could cut a dual kerf, so I went hunting for it.

This photo shows the result of a now straightend tooth ..



Regards from Perth

Derek

[Derek Cohen]

Is that all that happened? A bad cut?

Patty, I made about 4 cuts on my friend's slab, all the same. I know what to expect from my equipment. There was a problem.

Regards from Perth

Derek