kapex reb 120 BASE NOT FLAT AND FENCE NOT SQUARE
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usernumber1
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i'd like to get some input from experienced carpenters what precision is actually required.
the guy in the video arbitrarily decided that being accurate to 1 thou is important. Why stop there why not 0.5thou
he started with a 10thou and i'm not convinced that is a problem
the guy in the video arbitrarily decided that being accurate to 1 thou is important. Why stop there why not 0.5thou
he started with a 10thou and i'm not convinced that is a problem
Cheese
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usernumber1 said:
Not an experienced carpenter...just an average home owner that happens to machine metals and dabble in house improvement projects.
Depending upon the application, I really don't think a difference in .010" of deck height will make much of a difference for the typical application. The engineer in me says always strive for perfection...the practical side of me says .010" will probably be fine for wood.
Overall, the video seems more oriented to trying to extract $$$ from the sponsors. It's the exact reason I don't follow or look at this type of advertisement which in reality, is exactly why it was produced.
AlexThePalex
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I build a small deck three weeks ago. 12 boards of 4,5 meters long. I cut the wood on friday and piled them on top of eachother, lining up the ends to make sure they were all exactly the same length. When I came back next monday to install them they were all a different length, the longest was 9 mm longer than before. So there's your precision with woodworking.
Birdhunter
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I'm a retired engineer and an avid woodworker. I , when new, fiddled endlessly with my Kapex trying to get everything aligned using a Starrett straight edge. I ended up getting a perfect 90 degree cut using the left side fence. And a very slightly off 90 degree right fence cut. After I added sacrificial fences to both sides, I could shim the right side to a perfect 90 degree cut and the left side stayed at 90 dege=rees.
Before I added the shims, I never saw any assembly issues with the right side being slightly off. The Kapex isn't a precision machine tool and, for woodworking, it doesn't need to be. Most of the woods (mostly highly figured) move after being cut anyway.
If I need high precision cuts, I use my big SawStop and usually with a jig for added accuracy.
Before I added the shims, I never saw any assembly issues with the right side being slightly off. The Kapex isn't a precision machine tool and, for woodworking, it doesn't need to be. Most of the woods (mostly highly figured) move after being cut anyway.
If I need high precision cuts, I use my big SawStop and usually with a jig for added accuracy.
kevinculle
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IMHO only the miter angle calibration on a Kapex is worth dialing in as close as possible with the 5 cut technique, as small error in a wide miter can be quite visible...for checking table flatness an 0.01" (0.25mm) feeler gauge is fine.
Shopuld be flat just like the shoe of a track saw should be flat. Just like the base of a router should be flat. Just because wood moves doesn’t mean the wood cutting machinery should not be precise. Those who say otherwise are full of it. Period. Some kapex’s are flat some are not.
kevinculle
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The question is how flat...what deviation from flatness over the width of the Kapex table is acceptable. It isn't an optical collimator and we're not going to flatten it to within a half wavelength of UV light. It isn't a metalworking surface grinder producing precision gauge blocks and we're not going to flatten it to within 0.00005" over the surface. It's a miter saw and flat to within 0.01" is generally adequate for most work. If you are doing precision joinery with very short pieces you might need a bit better...maybe 0.005", but it's still a miter saw for working wood.
I would not necessarily consider Woodpeckers aluminum square and straight edges as "reference-grade" measuring tools.
In our toolroom, all the calibrated measuring tools are either steel, granite or stainless steel. Aluminum does not make the grade.
Aluminum has a higher expansion rate (probably not a factor here) and is far more easily damaged (a consideration). And while Woodpeckers aluminum squares are probably upper echelon for woodworking, they are not nearly the same as machinists' measuring tools.
All having been said, I don't think that the surfaces are that important for miter accuracy. Of greater importance is how the angles are indexed. Most saws use "as cast" detents (inherently inaccurate) for miter indexing. DeWalt uses a stamped metal plate for indexing (inherently much more accurate).
I have not examined a Kapex saw up close. How are they indexing? Miter angles are the key. Even the Dewalt chop saw will not match the accuracy of my dedicated 45 degree cut sliding table saw (from my old picture framing business).
When I started reading this thread I was hoping to hear something about the angular accuracy.
In our toolroom, all the calibrated measuring tools are either steel, granite or stainless steel. Aluminum does not make the grade.
Aluminum has a higher expansion rate (probably not a factor here) and is far more easily damaged (a consideration). And while Woodpeckers aluminum squares are probably upper echelon for woodworking, they are not nearly the same as machinists' measuring tools.
All having been said, I don't think that the surfaces are that important for miter accuracy. Of greater importance is how the angles are indexed. Most saws use "as cast" detents (inherently inaccurate) for miter indexing. DeWalt uses a stamped metal plate for indexing (inherently much more accurate).
I have not examined a Kapex saw up close. How are they indexing? Miter angles are the key. Even the Dewalt chop saw will not match the accuracy of my dedicated 45 degree cut sliding table saw (from my old picture framing business).
When I started reading this thread I was hoping to hear something about the angular accuracy.
I bought a Kapex at the end of last year. The first one was way out of flat and I returned it. The second one was still out of flat but not as much so I kept it since there would have been a long wait to get a replacement.
I did tons of tests with feeler gauges. With the saw set at 0° the saw is probably around 0.005 out of flat by the fence between the turn table and the extensions. As I bring the straight edge closer to the locking handle and make the same measurements the saw is out by over 0.010". If I turn the saw for a 45° miter and make the same measurements the error increases both by the fence but even more so as the straightedge is further from the fence.
What I came to discover is that I believe the base castings of most Kapex saws are warped. The turn table is slightly tilted up towards the locking handle on my saw because of this. This causes the turn table to be slightly lower than the extension wings by the fence and also causes the locking handle portion of the turntable to be much higher than the extension wings. When you rotate the saw to 45° then the locking handle, which is sitting higher due to the tilted turn table, is right next to the extension wing. Since it is sitting higher than the extension wings the straightedge will rock. If I put strong downward pressure on the handle of the Kapex with the straightedge still on the table the saw table is nearly perfectly flat. Maybe someone else who has an out of flat Kapex can try pushing down hard by the miter locking handle while taking measurements and see if it brings their table close to flat. I'm sure every saw is a little different but that has been my experience.
How flat is flat enough is a good question. When cutting tall baseboard in the vertical position 0.010" out of flat would definitely affect the cut in my opinion. For cutting 4/4 stock in the flat position the error would be next to nothing. Still it would be nice for a $1,500 saw if there was more quality control.
I did tons of tests with feeler gauges. With the saw set at 0° the saw is probably around 0.005 out of flat by the fence between the turn table and the extensions. As I bring the straight edge closer to the locking handle and make the same measurements the saw is out by over 0.010". If I turn the saw for a 45° miter and make the same measurements the error increases both by the fence but even more so as the straightedge is further from the fence.
What I came to discover is that I believe the base castings of most Kapex saws are warped. The turn table is slightly tilted up towards the locking handle on my saw because of this. This causes the turn table to be slightly lower than the extension wings by the fence and also causes the locking handle portion of the turntable to be much higher than the extension wings. When you rotate the saw to 45° then the locking handle, which is sitting higher due to the tilted turn table, is right next to the extension wing. Since it is sitting higher than the extension wings the straightedge will rock. If I put strong downward pressure on the handle of the Kapex with the straightedge still on the table the saw table is nearly perfectly flat. Maybe someone else who has an out of flat Kapex can try pushing down hard by the miter locking handle while taking measurements and see if it brings their table close to flat. I'm sure every saw is a little different but that has been my experience.
How flat is flat enough is a good question. When cutting tall baseboard in the vertical position 0.010" out of flat would definitely affect the cut in my opinion. For cutting 4/4 stock in the flat position the error would be next to nothing. Still it would be nice for a $1,500 saw if there was more quality control.
"...more quality control."
The head of Festool QA should pay a visit to the QA office of SawStop (if that has not already been done). She or he may learn a thing or two from them. I have had hands-on experience with or spoken to owners of 4 ICS, 5 PCS (including mine), 2 Contractor & 2 Jobsite (older version) SawStop saws. Zero complaints about their saws from Day 1.
How do they do that? The machines (up to 600 - 700 lbs (/)) are made in Taiwan, and shipped to this part of the world. How could they achieve and maintain the factory settings to spec. and most important, to the satisfaction of their customers? What QC process do they use? What equipment or test cuts (if any) do they put in place to be so successful? How about their sourcing of parts and metal? What kind of control do they have over their production partners, or assurance from them? What kind of people do they hire and train to be the gatekeepers? The fact-finding trip might not be possible before, but SawStop is now part of their family.
The head of Festool QA should pay a visit to the QA office of SawStop (if that has not already been done). She or he may learn a thing or two from them. I have had hands-on experience with or spoken to owners of 4 ICS, 5 PCS (including mine), 2 Contractor & 2 Jobsite (older version) SawStop saws. Zero complaints about their saws from Day 1.
How do they do that? The machines (up to 600 - 700 lbs (/)) are made in Taiwan, and shipped to this part of the world. How could they achieve and maintain the factory settings to spec. and most important, to the satisfaction of their customers? What QC process do they use? What equipment or test cuts (if any) do they put in place to be so successful? How about their sourcing of parts and metal? What kind of control do they have over their production partners, or assurance from them? What kind of people do they hire and train to be the gatekeepers? The fact-finding trip might not be possible before, but SawStop is now part of their family.
squall_line
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ChuckM said:
I work for a growing software and data company. Even in my past jobs the fiefdoms, silos, and egos often made this sort of mission seem unnecessary and/or much harder than it needed to be.
Birdhunter
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I own a SawStop ICS and a Kapex. I don’t expect the Kapex to exhibit the same dimensional quality as my ICS. They are totally different machines. The ICS is heavy cast iron machined to be very flat while the Kapex is made to be light and portable and within the budget of most woodworkers.
It would be interesting to see a sliding compound miter saw with machine tool specs. I probably could not afford it.
It would be interesting to see a sliding compound miter saw with machine tool specs. I probably could not afford it.
squall_line said:
To make a cross-dept or cross-business fact-finding initiative like that happen, the directive must come from the Executive Office or the parent company. In my previous life working in a decentralized healthcare setting (under a central health authority), we had a development team looking into and developing best practices for member hospitals. Centers of Excellence shared their polices and methods of work in both clinical and non-clinical areas.
Birdhunter said:
True that miter saws are not as robust as well-built table saws like the SawStop. But why are some Kapexes dead-on, and some not? My Kapex, as shared in another old thread, is flatter than flat for all woodworking purposes -- 0.0010 at the front near the locking handle. We should be able to see consistency (not perfection) in a miter saw that is among the most expensive ones that money can buy.
