Different Blade thicknesses - issue with guide?

[Roland Chung]

I forgot to switch back to my factory ts55 blade and cut through a piece of white melamine.  As I was cutting, I noticed a lot of black rubber chips flying - I was retrimming the "no chip" edge.  I checked the packaging and noticed that the original blade is 2,2mm and the panther blade is 2,5mm.

Is it safe to assume that this 2,2mm is the same as 2.2 mm - that the .3mm difference (probably split to the right and left of the blades center) is insignificant in regards to where the cut will be made when I set the edge of the guide rail on my mark?  I was just surprised to see so much new trimmings - probably more noticeable on the white melamine.

I'm not planning on having multiple guide rails for the different blades, but I am just curious if this has affected any projects?

 

[bruegf]

2,2 is our 2.2.  The Germans use commas instead of periods and periods in place of commas for numeric values.  As to how much of the .3 difference is on each side of the centerline would depend on if the blade bodies have the same thickness or not.  If the blade bodies are the same thickness then I would expect there to .15 mm extra cut.  If the blade body on the panther is also thicker then there would be less than .15 mm diffenece since the blade body registers to the saw on the inside surface of the blade body.  I think the key dimension is from the blade body to the side surface of the carbide tooth.

I don't have the panther so I can't say for sure.

Fred

 

[Tinker]

There was an earlier discussion on this very same topic. 
since that discussion, i have had some second thoughts on purchasing a panther blade as my all purpose blades are doing a good job.  i suppose the panther would go thru hard and/or thick lumber a lot quicker than my present setup.  I just could not see recutting the rubber strip every time i wanted to rip and then go back to cross cutting.  Roland just gave me a good solution.  i have several different sized guide bars in the old single channel style and several in the newer two channel style.  If i were to go for the panther, i could cut the strip on all of the old style for the panther and all of the new style (which I use most of the time) for my regular blades.  such a simple solution to a simple question that a simple mind was too simple to figure out the simple way.
Tinker

 

[Eli]

I gave the Panther a try. Honestly, the regular blade rips much more smoothly although not as fast. I'd rather trade speed for quality. And who really does want to recut the rubber strip if you don't have to.

 

[semenza]

Hi,

      I measured the blade bodies of the fine and universal blades (Uni is 2.5 kerf also) and they are the same. For some reason even though the difference should only be .15mm the result on the rubber splinter guard is much more. It is quite visible and does throw off the cut line by something more like a 1/32".  I used to have the Panther blade also and had pretty much the same results between Panther and Fine blade. I think Panther and Universal would be compatible.  I do plan on getting another Panther because, though the Universal is good, I found in the past that the Panther really does do a better ripping job on hard woods. I have used the Fine blade on ripping hard woods but I found it to be it slow, a little hard on the TS55, and got some burning also. Perhaps using the Fine blade for ripping with a TS75 would be better- more power and more teeth (might run a little cooler).

Seth

 

[Dave Ronyak]

When I switched the blade on my TS 55 from the original 48 tooth blade to the 28? tooth general purpose blade, I, too, noticed  rubber bits from the anti-splinter strip.  I have not gone back to the 48 tooth blade to see it the top inside edge of the cut is deteriorated due to the strip not reaching all the way out to the cut line.  To me, this does seem to be one annoying item that Festool should address with its blade manufacturers, so they all cut the rubber strip essentially the same.  Has anyone tried shimming the wider kerf blades outwardly (add shim before installing panther or 28 tooth blade on arbor) to prevent cutting more off the rubber strip relative to the edge produced by use of the 48 tooth blade?

Dave R.

 

[semenza]

Hi,

    The shim would have to be about 1/32" or maybe a bit more. Not the.15mm kerf difference.  I don't know off hand how long the projections are on the "keyed washer". But shimming may move it out too far to be safe. And even if it wasn't out too far there would still be less of the blade body thickness in contact with the arbor. I am thinking that this is not something to mess around with.

Seth

 

[Dave Ronyak]

Seth,

What you wrote makes a lot of sense to me.  Assuming the blade teeth are centered on the steel plate of the blade, and thus project equally beyond either side of the plate, the thickness of the shim required should be on half of the difference in "kerf width minus plate thickness" between any two blades, e.g. the 48 tooth blade supplied with the TS 55 and the optional 28 tooth GP blade or Panther ripping blade.  The shim needs to fully support the blade, as you said, for accuracy to prevent wobble (lateral runout).  Festool should address this problem by making this dimension the same on all its blades.  They certainly ought to be able to come closer than they do today simply by changing their specifications used for manufacture of the blades.

Dave R.

 

[Eli]

Maybe they want to sell a lot of splinter strips.

 

[Loren Hedahl]

I wonder if the blades are slightly conical, since it is much easier to get a stable rim that way.

Also, as the blade cuts, the rim heats via friction, and as the rim heats, it expands.  Slots help, but that expansion has to go somewhere.  If the blade is conical, rim expansion will flatten it out.

I'm probably way off base here, since I am not very knowledgeable about saw blade manufacture.  But it's early Saturday morning and my head somehow started working! ???