The Heavy Duty Knew Concepts Fret Saw

[Mike Henderson]

After the discussion of the heavy duty Knew Concepts fret saw, I decided to purchase one. I have the previous model and will use the two saws in my dovetails class.

The heavy duty one is larger because the part of the saw that you use to attach the saw blade has to protrude from the frame so that it can be rotated 360 degrees. You have to push the mechanism back to rotate it, which means you have to release the tension in order to be able to turn the blade.

Here's a picture of the two saws, the older one on top and the heavy duty one at the bottom.
2018-03-19-Knew-Concepts01.jpg

You can see in this next picture, where i laid the old one on top of the new one, that the thumb screws you use to attach the blade are aligned, but the frame of the heavy duty is wider.
2018-03-19-Knew-Concepts02.jpg

As far as use, they're pretty much the same. I did some sawing with one and then with the other and I couldn't tell any difference. The blade is about the same tension on both.

The extra weight of the heavy duty one did not affect me at all. I didn't really notice it in use.

For the small difference in price, I suppose I'd recommend the heavy duty one just because it can rotate 360 degrees, although I don't expect to need that capability.

Mike

[lowell holmes]

I have the original saw. I discarded my coping saws after getting it. I don't think I see a need to upgrade. The saw is really stiff.

[Frederick Skelly]

Thanks Mike! Looks like you beat me to it - I was planning to post a review tonight, so I'll just combine my comments with yours to keep all of them in one thread. Hope you don't mind.

For everyone, I only have the HD (MK-IV) version. But here are my thoughts:
* First, I LOVE THIS SAW! It is as good as you folks all told me to expect.
* Fit/finish was good. Red powdercoat. Everything machined nicely.
* Mine weighs 8.0 oz. According to Highland WW, the "old" one (MK-III) weighs just over 5 oz. Personally, I think I'd notice the 3 oz difference in weight (60% more) if I'd started with the MK-III. But not knowing any better, I can easily live with it.
* Frame very rigid. I detect no flex in any plane while in use, whether sawing at 0*, 45* or 90* (horizontal).
* Easy to insert blades and to tension. A very minor thing - from what I can tell, the only way to judge if you have overtensioned the frame is if the blade comes out of the holder or breaks. According to KC Customer Service, the blade should sound a high note when you pluck it, if it is tensioned enough. More on tensioning later....
* I tried a #7 (14.5 tpi) Pegas blade and a #5 (12.5 tpi) Olson blade in both 1/2" and 3/4" thick wood. I agree that - as you'd expect - the 12.5 tpi cuts faster and leaves an acceptable finish for dovetailing. I think I'll stick with 12.5 since everything I do is in that range.
* I compared the performance and feel of the saw at 90* vs 45*. I didn't see a difference and could easily do with only having 45* swivel: i.e., 90* is nice to have as an option but not required for me personally.
* The tensioning screw on mine spun very freely, making it hard to keep a consistent tension when you tension/de-tension a couple times with same blade. Turn the nut around so that the engraved line faces the saw handle. That solves it immediately. Turns out the engraved line is an indentation from where they whack the nut with a cold chisel to give the nut more bite. But on my saw, the line was facing away from the handle and I wasnt getting the benefit of the "whack". Not sure I completely understood this - something about the whack constricting the threads - but KC said to turn the nut and that did solve it.
* Haven't decided what I think of the handle yet. Been a couple good posts lately on replacing it though. Can't see spending $85 to buy a new handle when I have a lathe.
* KC Customer Service was EXCELLENT. My blades kept popping out even at low tension. After a couple emails, KC's Brian Meeks (the man in several interviews and videos) sent me his cell phone number and suggested we work the problem together via Facetime or Skype. We talked through a couple things and my saw seemed "fixed". But he also steered me to a troubleshooting video on the KC website in case I needed it. Well, right after I hung up, the dang blade popped out AGAIN. I followed the video and used it to adjust the blade clamps. Now I'm getting better tension and grip on the blades. Note: Different brands of blades may take more or less tension before popping out of the blade clamps. Adjust the tension by 1/4 turn of the tensioning knob at a time.

Bottom line for me: If you are comfortable sawing at 45*, rather than horizontally (90*), go for the lighter MK-III saw. If your work would benefit from being able to rotate the blade 360*, or if you want absolute rigidity in the frame - get the MK-IV. Or, if you want the best/latest and don't care about the extra 3 oz, get the MK-IV. The difference in price is a Starbucks - $6.

I LOVE THIS SAW! I am now a "saw out the waste" dovetail man because it is so good.

Fred

[Kevin Smira]

I too have this saw. I have it in the 5” version. I use it for wasting dovetails. I had the same issues with the blades popping out and Brian called me to discuss. Same video to watch, etc...eventually, I got it to where I want d it and it’s been bulletproof since. I tried once using a “regular” coping saw and it was garbage. For me, I try to take my dovetails “straight from the saw” and not touching the walls of the joints with anything other than my DT saw. Chisel our the waste left by the KC fret saw and fit the joint.