Reverse tooth Gap question.

[Rolf]

I will be doing a zoom presentation on scrollsaw blades for our club and made an interesting discovery.
I will be using my EX 16, the upper arm is parallel to the table and I have the Pegas clamps on it. I put in a Pegas MGT 1R blade and then a Olson 2/0R to see how far up the gap between the down and up cutting teeth comes above the table. It comes up at least a 1/4 (will measure more precisely later) That can be a real problem when cutting delicate projects in thinner material.
You have this huge gap that is chomping up and down.
I am curious if anyone has a EX16 with the stock clamps or check any EX style saw to see how far up the gap comes.

[will8989]

Which one comes up higher?

[Rolf]

Betty, I will do some measurements later.

[GladeFade]

I find it difficult to use rev blades since I have an Eclipse saw with 1 1/2 stroke so it comes up higher than other saws.
So it's not just the blade maker but also the saw maker that effects the cutting.

[Rolf]

I did a bit more investigating and realized that there is really isn't anything wrong. There are reverse teeth coming above the table, the only thing the Pegas gap on this blade is huge. That is one reason why we need to stack cut thin material other than just for productivity.
I checked once again that my upper arm on The EX was parallel to the table. The Pegas MGT #1 has three reverse teeth come up above the table, it only has 13.7 TPI so that is OK. The Olson 28TPI has more.

I selected these blades to demonstrate the differences between them for our new members. I will also do an image of the Pegas 2/0 R with 15.4 TPI. to help people understand that it is not jus the Blade number but the TPI that is important. This really points out the need to stack cut thinner material.
Olson 2-0 reverse.jpg Pegas #1 .jpg Olson 28TPI BB.jpg Pegas MGT 1 13.7 TPI BB.jpg

[Linda In Phoenix]

Rolf, I have an Ex-30 and concur with your results. It helped me remember why I prefer FD ultra reverse blades—so the alternation between the two directions isn’t so different. But a support back piece never ever hurts with any blade!

[Rolf]

I have never gotten used to the Ultra reverse blades, it is counter intuitive to me having teeth facing each other trapping sawdust. But lots of folks swear by them.

[Jimern]

Blade mounting position is important too. On the excaliber, the blade can be mounted vertically about 3/8 of an inch in variance, by design or by mistake. That will also affect how many of the reverse teeth come above the table top during the saw stroke.

Reverse teeth are nice to have, they do minimize clean up, but there are blades that do not have reverse teeth widely in use too.

I think you found the key though, TPI is the most important aspect when comparing different blade manufacturers.

On a personal note, I rarely find the need to use anything below a MGT #3

[Rolf]

turers.

On a personal note, I rarely find the need to use anything below a MGT #3

Jim, the majority of my work is done with a 3 or smaller. I have always gone with a smaller blade than normal people