Sunday, January 28, 2018

Ichthys Scroll Saw Pattern.


Bevel cut Ichthys. This board is 8.5 inches X 4 inches X 3/4". The internal letters are cut with the blade set at 90 degrees to the table. The table/head is then tilted a to a small angle and the exterior of the ichthys is cut. The ichthys then is pushed out until it wedges in place. Details in the pattern.

Pegas Upgrade Blade Clamp Heads: In-depth review.

I received a set of the Pegas Blade clamps for review. You may have seen them advertised in the latest edition of Scroll Saw Woodworking and Crafts magazine. These new heads are replacements/upgrades for the Excalibur, Excelsior, Seyco and King and Jet scroll saws. I have put them on my Excalibur, Seyco, Jet and DeWalt saws. The DeWalt is not officially supported but I installed them anyway to see what would happen.

If you own or are thinking about the Jet JWSS-22, make sure you read that section. It is significant. Top blade feeding is now supported with this upgrade.
I will talk about this upgrade on the Jet JWSS-22 saw at the end. In my opinion this upgrade has the most impact on the Jet saw. 

The ad copy from Pegas reads like this
40% lighter
Reduces vibration
Ease of use.
Reduces stress on the machine increasing the life of the machine.
Changing blades is easier and faster.
The kit comes nicely packaged with everything you need including a set of thumb screws. There wer no instructions in the box but replacement is simple. 
 To remove the hold head you simply remove the two bolts.  Removal required a 3mm allen wrench and a 7mm open end for the nut. After you remove the bolts slide the head off. Pay attention because the head captures two bearing in the arms. Remove the bearings. 

The kit comes with new bearings. Install the head and insert the bearing and bolt through the head and arm. Don't over tighten the bolts. Just snug them down.

I started on the Excalibur. After installing the head I ran the machine for several minutes. Everything ran fine. The only slight problem I had was that the tension arm poped up a little just when the saw started. It did not come up enough to change the tension but I need to troubleshoot that when I get a chance. That did not occur on the other two machines I tested.
 I installed on the DeWalt second but I'll talk about that below. 

I did the next installation on the Seyco ST-21.  I ran the Seyco with the new clamps for several minutes and again everything went fine. I did not experience any issue with the tension lever popping up.  



Let's talk about the DeWalt for a minute. Pegas does not mention the DeWalt as a machine these clamps are compatible with. If you should try them on your DeWalt I don't expect you will get any support. 

The DeWalt is different because of the upfront tension lever. If you use the new Pegas heads you will have two tension levers. I got around this by using the built in tension lever as a rough adjustment. Then I could use the new tension lever to apply the final tension. This seemed to work fine.

Let's talk about the advertising claims.

Weight: 40% lighter

I spoke with a friend down in Atlanta about how important the weight is at the end of the arm on reliability. Bob has torn apart more scroll saws than anyone I know. I consider him as good of an expert as there is for actual real world problems.

Bob is convinced that any extra weight at the end of the arm is definitely a factor on the life of the hardware in the saw. Especially bearings. He has tested this through lab measurements and real world cases.

So with that said how much difference did I measure in the new Pegas heads and the Seyco ST-21 heads. Pictures below.  
The complete set of Seyco heads weighs in at 131 grams. 
The complete set of Pegas replacement heads is 88 grams.

My math stinks but I think that calculates to the Seyco heads being 48% heavier than the Pegas heads.

I would need much more information to be able to put a number on how much that weight difference makes in reliability. 

Without more information from the manufacturer here is my guess. If you use your scroll saw every day for a few hours (Believe or not there and scrollers out there cutting full time) then I believe the impact on your machine would be significant. I am making that guess based on real world cases where full time scrollers use large aluminum knobs on the thumb screw. The large knobs are for comfort and that's great but they do see increased worn out parts from the extra weight.

If you are a weekend scroller or less, then I suspect the impact of this upgrade on reliability will be minimal unless you keep the machine for years.

 Vibration: 

The following pictures are my test in the shop on these machines with and without the new Pegas heads. This is far from scientific. This is just a measurement. I used a vibration meter app to measure the z axis vibration while each machine was running at it's full speed. 

The results are strange and this could be explained by several factors including just being a bad test. It also might be accurate. You decide.

The Excalibur and Seyco both showed more vibration in the z axis(up and down) by a significant percentage. Let me explain what that means. It is significant only in the percentage of the number. Real world, I could not feel the difference in vibration while cutting. I could only see it on the meter. 
With either set of heads installed both machine ran smoothly.
  
Surprisingly the DeWalt DW788 showed a slight improvement with the new Pegas heads. Also notice that this specific DeWalt saw showed considerable less vibration than the other two saws. This DeWalt saw is over ten years old. It is a type one and has always ran extremely smooth. When I compare it to other DeWalts is has the lowest vibration I have seen. Unfortunately this is not the norm.

My conclusion from this vibration test is, I don't know. My assumption was that with the reduction in weight I would see a reduction in vibration. Bad test? I just don't know.