Pegas Blades

[btseed357]

I have been using the Flying Dutchman UR blades on a Dewalt for years. When the blade became dull or worn, it would slow down its cutting or break. I recently purchased a Pegas and some Pegas MGT blades. One thing I'm noticing on my blades that after a turn, many times the Pegas MGT do not straighten, but remained in a somewhat twisted state which causes the cutting to drift. This has happened on #3 and #5 blades. I have a picture attached, hopefully someone will be able to make it out and provide an explanation on why it is doing this. I never had the problem with the FDUR blades.

Thanks in advance,

Bob

[kmmcrafts]

In my opinion if you're able to twist a blade like that then you have a tensioning issue.. maybe not enough at the start of the cut or slippage once you start cutting.. I don't know but I have had instances where a blade would twist some.. maybe not that much but anyway it was always because the tension on the balde wasn't enough.. You might try cleaning your clamp screws where they pinch the blade and also sand the ends of the blade to remove the oils from the blade.. they're coated to prevent rusting andover time they'll build up oil on the clamping screws. 

There may be a different issue here with your situation but that is what I've always had happen when a blade slipped in the clamp. 

[BadBob]

I use pegas MGT almost exclusively, and I have never seen them twist. This looks more like a bend than a twist.

[NC Scroller]

Another MGT fan. Never had that issue.  I agree it appears to be a tension issue.

[Denny Knappen]

Yes, it looks like a tension issue.  One way to tell, apply tension, then release the tension.  If there is a bow in the blade, it is a tension issue.  Tension issues are usually caused by the set screw or thumb screw.

[btseed357]

6 hours ago, BadBob said:

I use pegas MGT almost exclusively, and I have never seen them twist. This looks more like a bend than a twist.

Thanks, the bend is not uncommon, if you look at the teeth, you will see some facing straight while others facing left. Others have suggested a tension issue, I will look at the tension.

[rash_powder]

2 hours ago, Denny Knappen said:

Yes, it looks like a tension issue.  One way to tell, apply tension, then release the tension.  If there is a bow in the blade, it is a tension issue.  Tension issues are usually caused by the set screw or thumb screw.

So if the tension is too high the blade will bow when released?  I've been wondering a great while if I was tensioning correctly.  The high c thing doesn't work for me.

[Dak0ta52]

Just to throw this in, and something I have experienced, if you're cutting a turn and rotate the piece to quickly without allowing the blade to "cut" through the turn (especially sharp turns), it will bend the blade. This is more noticeable with the larger blades because the kerf has more surface area to bend the blade before it is allowed to cut it's way though.

Concerning the tension: I bottom feed and there are times when I'll feed the blade through the piece and it will not be directly aligned between the clamps. I'll clamp the blade to the top clamp, apply tension and as I do, it moves (aligns) the piece between the clamps. I'll then remove the tension, unclamp the top, and then reclamp the blade with the hole directly between the clamps. I've also found that if I'm experiencing excessive drift or I'm having to excessively rotate the piece to follow a curve, I know the blade has loosened and needs to be repositioned in the clamp for proper tension.

[btseed357]

4 hours ago, Denny Knappen said:

Yes, it looks like a tension issue.  One way to tell, apply tension, then release the tension.  If there is a bow in the blade, it is a tension issue.  Tension issues are usually caused by the set screw or thumb screw.

Thanks, this was new to me. The majority of the time I’m doing inside cuts, so when I release tension, it’s not something I usually look at.  This turned out being a 2 fold problem.  The bulk of the problem was the tension adjustment. The other part of the problem was that the bottom clamp nut had backed out slightly causing the hex nut to recede and the blade was slipping slightly but not enough to for the blade to slip completely out.

Thanks to everyone for their help. 

[btseed357]

2 hours ago, rash_powder said:

So if the tension is too high the blade will bow when released?  I've been wondering a great while if I was tensioning correctly.  The high c thing doesn't work for me.

This was the first time I’ve heard that as well and he was right on the money. 

[kmmcrafts]

2 hours ago, rash_powder said:

So if the tension is too high the blade will bow when released?  I've been wondering a great while if I was tensioning correctly.  The high c thing doesn't work for me.

 

33 minutes ago, btseed357 said:

This was the first time I’ve heard that as well and he was right on the money. 

I don't think he meant if the tension is too high.. I think he said if you tension the blade then release the tension and the blade has a bow in it then the blade chuck screws are likely slipping.. I didn't see anywhere he mentions tensioned too high.. I don't think you really can tension too high can you? well maybe because then you'll likely break a blade. 

EDIT: I don't think there is anyway to adjust the tension of the blade on a Pegas saw? There is no way to adjust it on the Excalibur unless you have one of the older models. 

Edited October 22 by kmmcrafts

[btseed357]

2 hours ago, kmmcrafts said:

 

I don't think he meant if the tension is too high.. I think he said if you tension the blade then release the tension and the blade has a bow in it then the blade chuck screws are likely slipping.. I didn't see anywhere he mentions tensioned too high.. I don't think you really can tension too high can you? well maybe because then you'll likely break a blade. 

EDIT: I don't think there is anyway to adjust the tension of the blade on a Pegas saw? There is no way to adjust it on the Excalibur unless you have one of the older models. 

Sorry, I should have clarified, the tension was not correct for the position of the blade. You are correct.  The Pegas does have a tension adjustment in the back of the saw 

[kmmcrafts]

1 minute ago, btseed357 said:

Sorry, I should have clarified, the tension was not correct for the position of the blade. You are correct.  The Pegas does have a tension adjustment in the back of the saw 

If you use that knob at the back of the saw you'll be getting the upper arm all out of adjustment.. that knob is to adjust the height of the upper arm so that it is parallel to the saw table. The upper arm should measure the same distance to the table at both the front of the saw and at the back of the saw.  

[btseed357]

36 minutes ago, kmmcrafts said:

If you use that knob at the back of the saw you'll be getting the upper arm all out of adjustment.. that knob is to adjust the height of the upper arm so that it is parallel to the saw table. The upper arm should measure the same distance to the table at both the front of the saw and at the back of the saw.  

The knob sets the tension and the lever applies the tension set after a blade change. 

[OCtoolguy]

I've always questioned the tension method on my EX's too. If I left the rear knob at the same spot when going from a 5 to a 1 or 2 mgt. As soon as I'd flip the lever the blade would break. So I had to back the knob off a 1/4 turn or so. 

Edited October 23 by OCtoolguy

[kmmcrafts]

50 minutes ago, OCtoolguy said:

I've always questioned the tension method on my EX's too. If I left the rear knob at the same spot when going from a 5 to a 1 or 2 mgt. As soon as I'd flip the lever the blade would break. So I had to back the knob off a 1/4 turn or so. 

I've never changed the knob on mine even going down to the 2/0 blades I use sometimes.. however I do mount the blade slightly loose, as in on the larger blade I push down on the upper arm slightly as I lift up on the blade that is already clamped in the lower chuck to take out any of the "bearings slack".. but I don't do either on the smaller blades. 

[kmmcrafts]

3 hours ago, btseed357 said:

The knob sets the tension and the lever applies the tension set after a blade change. 

I stand corrected.. I looked at the manual and it does say to use the knob.. 

That all said, I've been told that once you set that knob to get the upper arm parallel don't touch it again or you'll get it all out of tune. I suppose that since I rarely have the need to change any tension anyway because I mostly only use one size blade in that particular saw anyway. 

[BadBob]

6 hours ago, kmmcrafts said:

That all said, I've been told that once you set that knob to get the upper arm parallel don't touch it again or you'll get it all out of tune. I suppose that since I rarely have the need to change any tension anyway because I mostly only use one size blade in that particular saw anyway. 

I carefully aligned my EX21 to parallel the table and never touched the knob again. I have never had an issue using anything from #1r to #9r mgt blades. The same holds true for my Pegas saw.

 

[BadBob]

When mounting a new blade in my EX21 or Pegas saw, I tighten the clamps and flip the tension lever on and off. If the blade is not inserted perfectly vertically, there will be a bow in the untensioned blade. If I see a bow, I release and retighten one of the clamps and the bow goes away. If you get it inserted perfectly there is no bow.

[btseed357]

7 hours ago, kmmcrafts said:

I stand corrected.. I looked at the manual and it does say to use the knob.. 

That all said, I've been told that once you set that knob to get the upper arm parallel don't touch it again or you'll get it all out of tune. I suppose that since I rarely have the need to change any tension anyway because I mostly only use one size blade in that particular saw anyway. 

I agree that the tension should rarely, if ever, need to be adjusted. My Pegas is brand new and I have read that everything is set so it should work correctly out of the box. Mine was not, which was actually beneficial because with all of the input on this post, I actually learned something for a change.

[kmmcrafts]

1 hour ago, BadBob said:

When mounting a new blade in my EX21 or Pegas saw, I tighten the clamps and flip the tension lever on and off. If the blade is not inserted perfectly vertically, there will be a bow in the untensioned blade. If I see a bow, I release and retighten one of the clamps and the bow goes away. If you get it inserted perfectly there is no bow.

Yes, I also do that.. I forgot to mention that part too.. Here's the thing with these types of saws that do not have a "actual tension lever" like the DeWalt etc. is that there are a lot of bearings and linkages where slack can be.. and once you apply tension it takes that slack out sometimes and then releasing that tension will show that your blade was maybe in right but it took up all the slack in those arms.. These saws have about 20 ish bearings between all the linkages etc.. that can have a lot of slack by the time it gets to the front of the saw. Especially if you have a older saw that may have slightly more wear on all of those pivot points etc. 

[kmmcrafts]

1 hour ago, btseed357 said:

I agree that the tension should rarely, if ever, need to be adjusted. My Pegas is brand new and I have read that everything is set so it should work correctly out of the box. Mine was not, which was actually beneficial because with all of the input on this post, I actually learned something for a change.

Been scrollsawing for 20+ years and still learning new stuff.. Had many various types and brands of saws etc.. each one has a different set-up for different types of cutting.