Thread: DOMINO Cutter Life

I have no idea as I only bought mine 2 hours ago. However, Kevin (Festo agent) said not to force the cutter when using it and the cutter will last a long time and make smoother holes.

I mainly use 10, 8, 5 ,6mm in that order.

I love the 5mm for joining table tops and panels, they are just perfect. Super quick, minimal waste to remove and perfect alignment.


The 10mm is the most common size i use. In the 9 months ive been using Domi in a small shop production enviorment, im just about to finish my 6th box of 10mm, and at 510 per box thats over 3000 10mm mortices and the cutter is no where near the sharpen stage (or replacing if it carnt be sharpend) Amazing stuff. My 5 and 6mm cutters will probably never need sharpening/replacing.

On that note, can a cutter be sharpend? The unusual set of the cutter would mean a one off set up in a sharpening shop, and im not sure id trust the one i deal with.

That's brilliant!

You could touch up top of the cutter yourself, but as far as I can make out, sharpening side of the cutter would change the diameter of the cutter and mortise ever so slightly.

I know Festool don't intend for them to re-sharpened, so it's good they last so well.

Originally Posted by nt900

I know Festool don't intend for them to re-sharpened, so it's good they last so well.

Anthony i havent the slightest issue if the cutter is throw away (actualy ill send it to Bodgy ) Anyone here that isnt using it in a work enviorment will have theirs for 10 years barr hitting metal But they are brilliant.

Originally Posted by nt900

That's brilliant!

You could touch up top of the cutter yourself, but as far as I can make out, sharpening side of the cutter would change the diameter of the cutter and mortise ever so slightly.

I know Festool don't intend for them to re-sharpened, so it's good they last so well.

Sorry Anthony, but that is not correct. Festool-Germany specifically states that the mortising bits were designed from the outset with sharpening in mind. Depending on the abilities of the sharpening service, they can be sharpened between 1 and 3 times (for a total of 1mm) before they become too short.

You are correct that the sides should not be re-ground, but a good sharpening service would/should know this.

As for the length of service life between sharpenings, this is estimated between 4,000 and 10,000 cuts, but I can't find the email anymore. The reason why this is so high is because the bit remains much cooler than other cutters because it is constantly sweeping across the cut instead of sitting in the same bore.

Originally Posted by Powertoolman

The reason why this is so high is because the bit remains much cooler than other cutters because it is constantly sweeping across the cut instead of sitting in the same bore.

There's that, plus the chip extraction by the spiral cutter, which in turn is usually assisted by a shop vac. The movement of the cutter makes the spiral much more effective IMHO.

Surely the nature of the timber being cut must be taken into consideration. I can't believe you'll get the same number of cuts when processing Ironbark day after day as compared to Pinus radiata.
Incidentally, what happens to the accuracy of cut dimensions as the cutter wears. Someone with experience at very high precision work could tell us I guess.

Originally Posted by Flowboy

Surely the nature of the timber being cut must be taken into consideration. I can't believe you'll get the same number of cuts when processing Ironbark day after day as compared to Pinus radiata.
Incidentally, what happens to the accuracy of cut dimensions as the cutter wears. Someone with experience at very high precision work could tell us I guess.

I think it goes without saying that the type of timber will vary the life of the cutter. Also the impurities in the timber will cause variation. I am fairly sure that Festool would have chosen a medium hardness timber to base their life expectancy on (not balsa).

As for the cut dimensions, Festool don't recommend sharpening the flutes, and recommend sharpening a bit from one to three times, up to a mm, is clearly their tolerance allowed. Wear on the sides will be minimal. Any wear will be taken up by the domino and glue when it is inserted in the slot.

One of the many things I admire about this tool is the fact that critical tolerances are avoided by the design, but still allows great accuracy.

Flowboy,
Where are you getting these claims from? I have never seen anything like this presented by Festool.

Originally Posted by Flowboy

Groggy,
Festool's quoted data are at best suspect and at worst unbelievable. No independant source is involved in any assessment. We say it, it so believe it. As their is no way of knowing what timber has been used to assess the life of a cutter and as there is no way of knowing whether this timber all came from the same source at the same time, or even if their is ongoing repeition of quality assurance, the variation could be as much as 500 cuts to 20,000 or more using only "some timber we chose". "Fairly certain" isn't sufficient. As the tolerance of change of cutter tip diameter is up to 1mm, then there is no way anyone can claim to be able to perform precision cuts to 1/100th of a mm. These are issues which are important in assessing the performance of the tool in one's own hands. As eluded to in another thread, errors must be taken into account for each cut. Factors such as accuracy and precision must also be considered along with errors of measurement. At best I would assume you could claim consistently, 1/10mm variation cut to cut. Glue or not withstanding.
I love their tools, but have no respect for their data.

Which quoted data are you refering to? I have only seen Powertoolmans reference to what he though he recalled from an email, not a quoted reference.

My "fairly certain" is based on some knowledge of design engineering and supportability requirements. For Festool to accurately provision spares they must have an idea of what the life of the primary wear component is (if no other parts are measured, they must do this one). In fact, I'd go so far as to state they'd be stupid not to do this in their scale of operations, and Festool are not stupid.

The one mm wear is based on the depth of cut, NOT the critical diameter of the cutter. Any minor wear of the sides of the cutter will result in a tightening of the tenon in the hole, not a loosening. This wear will be minimal and taken up by compression of the wood fibres (dependant on the type of timber). Again, by design, wear in the cutter will not affect the placing of the center. It may (and I stress may), provide a compounding error over a series of holes.

For tolerances of .01 of a mm - I just don't know. Personally I've never done anything that exacting in wood. If I did, I'd use a timber that allowed some 'give' or change the design of the piece. I'm not saying it can't be achieved, far from it, some of the expanding tables use high tolerances, just that it enters a diferent realm of WWIng, perhaps closer to a pattern makers craft.

Finally, you said that "As the tolerance of change of cutter tip diameter is up to 1mm", where do they state that? Powertoolman referred to a reduction in length, not diameter, and he is not "Festool".

Originally Posted by Flowboy

As the tolerance of change of cutter tip diameter is up to 1mm, then there is no way anyone can claim to be able to perform precision cuts to 1/100th of a mm.

Flowboy,

Wouldn't it be better to read what was said before alleging that the tolerance of 1 mm is in cutter diameter, and therefore getting heated about it. The tolerance is in fact in cutter length.

Someone else pointed this out; but it was apparently water off a duck's back.

Rocker

Originally Posted by Flowboy

Groggy,
This is exactly my point. .

No, it isn't. You have unfairly misquoted him. He stated quite clearly what he knew as fact,

Festool-Germany specifically states that the mortising bits were designed from the outset with sharpening in mind. Depending on the abilities of the sharpening service, they can be sharpened between 1 and 3 times (for a total of 1mm) before they become too short.

he also pointed out where he agreed with Anthony:

You are correct that the sides should not be re-ground, but a good sharpening service would/should know this.

and clearly distinguished it from what he could no longer verify -

As for the length of service life between sharpenings, this is estimated between 4,000 and 10,000 cuts, but I can't find the email anymore. The reason why this is so high is because the bit remains much cooler than other cutters because it is constantly sweeping across the cut instead of sitting in the same bore.

Originally Posted by Flowboy

The whole thing is based on assumption and on vague, supposed data received via a missing email.

No, in the worst case you can only possibly attribute that statement to his last sentence.

Originally Posted by Flowboy

No he's not Festool, but he claimed to have the information straight from Festool and posted it in confidence of his knowledge, but now way of backing it up.

Once again, he clearly differentiated between what he claimed was 'fact' and what was recollection from an email he no longer had. The reader is in no way misled as to the veracity of the information he has presented.

In fact, Lignum's experience seems to agree with a long lifed cutter.

Originally Posted by Flowboy

I'll agree to disagree and leave before I'm threatened again.

You have accused him of providing innaccurate information yet have provided nothing contrary. You have further suggested that either he or I are likely to threaten you which is not the case. Certainly from him as he resides in the USA. In fact, this type of ad-hominem attack makes you the aggressor.

Um..why do some people get so hot under the collar about tools. What is Flowboy's main problem? Surely regular proper use of the Domi will naturally result in worn cutters eventually. Like drills wear, chisels wear etc. I'll just go out and buy a new one if it can't be sharpened. Chill guys.

Sorry Anthony, but that is not correct. Festool-Germany specifically states that the mortising bits were designed from the outset with sharpening in mind. Depending on the abilities of the sharpening service, they can be sharpened between 1 and 3 times (for a total of 1mm) before they become too short.

You are correct that the sides should not be re-ground, but a good sharpening service would/should know this.

As for the length of service life between sharpenings, this is estimated between 4,000 and 10,000 cuts, but I can't find the email anymore. The reason why this is so high is because the bit remains much cooler than other cutters because it is constantly sweeping across the cut instead of sitting in the same bore.

Powertoolman - good points you raise, although you have been privy to some information I have not - I will have to fix that . I have looked through my service doco and cannot find anything relevant. This is sort of why I started this thread to get horses mouth data.

Just to clarify my comment:

I know Festool don't intend for them to re-sharpened, so it's good they last so well.

I say this in the context it being obvious you cannot sharpen the sides of the cutter else you change the dimension of the mortise. But I did not consider a partial sharpening - tip cutters only. So I might have dropped words in Festool's mouth if they intended partial sharpening.

My personal opinion, I would not generally bother to have cutters resharpened for the following reasons:

• Evidence so far indicates they Domino cutters will make a awful lot of mortises before requiring resharpening. I am likely will wear out some of my hand plane blades or chisels before I wear out a Domino cutter. If someone asks me what I do with planes/chisels to wear them out so quickly I might be brave enough to admit some bad habits in a public forum.

• The cutters are not a high cost item and the cost of resharpening is likely to be a relatively high percentage of the purchase cost of another cutter. And...

• after paying the price for the resharpening I may get it back poorly sharpened - I once received a saw blade back from the sharpening service with different tooth profile than the one it initially had . I am not sure the average sharpening service knows what a Domino cutter is and how it should be sharpened. I don't want to do them all a disservice, but they could think it fine to change the overall diameter of the cutter, as it can be acceptable with some router bits. After some time when sharpening services are used to sharpening Domino cutters on a daily basis, this concern could be alleviated. I say could be - but the saw blade incident puts this in doubt. By-the-way, if someone can recommend a very good sharpening service in Melbourne I would be happy to know about it. I have a small but growing pile of Festool circular saw blades requiring some attention. As I have to maintain perfect demonstration tools, my current MO is to use a new blade whenever I know or suspect I'm not getting best performance.

• There is an inconvenience factor with having a blade or cutter away from the workshop. I would probably need to have a second cutter on stand-by. Or plan to send them away during an off time.

Having said all that, I would be prepared to do is touch up the cutter tip myself to get a little more life from it and keep it as a second cutter in case the new one gets prematurely damaged. Something specific to my use of the Domino, before wearing it out I am more likely to do catastrophic damage to a cutter by plunging it into something it was not intended to deal with, like a nail or 30 year old timber bog, a screw or such. I have not hesitated yet to use the Domino on timber in-situ which may have ugliness underneath the surface where I cannot predict it exact position. So far I have been lucky, or possibly cut straight through something and not noticed the damage.