Blade Breakage

[Rockytime]

I'm cutting fret work from 1/4" BB stacked on 3/16" underlayment. I am using a 2/0 Pegas MG blade at 1300 SPM. A blade only lasts about 10 minutes and then breaks. I can feel the blade getting a bit dull and then snap.  I don't mind buying blades but am just wondering if my blade breakage is unusually excessive. I'm aware plywood is a little rough on blades.

[kmmcrafts]

I rarely use a blade that small.. but plywood does chew up the blades fast... I've never broke blades like this with my DeWalt and Excalibur saws.. But every one of my Hawks will break blades when they get dull like this... Problem is.. I run a blade way too long sometimes.. also the Pegas blades seem more fragile than the FD blades.. Never break the FD blades or at least very rarely do I break them compared to the Pegas.. I get between 10-15 minutes of cutting on a blade with my Hawk.. The Excalibur get 15-20 minutes before it gets dull to the point of pushing hard to get through the wood.. Those numbers almost double when cutting solid wood.. so yeah the ply is really tough on blades..  

[ike]

I tried pegas blades and found out you have to run them at a slower speed. and Idondddddd't use a blade that small very often. ecept when cutting  puzzles with no more than 2 pieces of .200 plywood. dI went back with olson match blades.

IKE

[stoney]

9 hours ago, Rockytime said:

I'm cutting fret work from 1/4" BB stacked on 3/16" underlayment. I am using a 2/0 Pegas MG blade at 1300 SPM. A blade only lasts about 10 minutes and then breaks. I can feel the blade getting a bit dull and then snap.  I don't mind buying blades but am just wondering if my blade breakage is unusually excessive. I'm aware plywood is a little rough on blades.

Les, I can't remember the last time I used a 2/0 blade.  I have found mostly the smaller the blade the shorter time it lasts.  When you think about it smaller blades have smaller teeth and less material to dissipate any heat created in the cutting process.   We all know heat and twisting motion are both enemy's of scroll saw blades.  My philosophy is to not use a smaller blade than required to get the job done and it has served me well.   

Edited September 26, 2019 by stoney

[crupiea]

I use that size blade on 1/8" bb only, any larger and it breaks or just is too hard to control.  Also try going slow.  That way the blade wont heat up as much. 

[Scrappile]

I agree that blade may be a little too small for 7/16" thickness of plywood.  Plus I find the Pagas blades a little smaller than the same sized FD blade, not sure about other brands.  Might try around a Pegas #3 reverse skip for that thickness..that is what I use for around 1/2" stock, if I want to use Pegas...That is just me, doesn't make it right.

[CharleyL]

Try slowing the blade speed. An overheated blade will break easily. I also use a piece of paraffin wax rubbed against the sides of a moving blade for lubricant and to keep it cooler. Small blades require a little less tension too, but still break easily and dull quickly. Look closely at the sides of your broken blade to see if it has changed color in the cutting area when compared to the end color. If it's changing color you are overheating the blade. The increased temperature will cause the metal to become brittle and it will break much more easily as it becomes brittle.

Charley

 

[SCROLLSAW703]

Howdy Mr. Rocky,

Good to see yer post, Sir. I have been in & out, seein' what ya guys are up to, but not much to tell about here. I'll pm ya.

In my scroll projects, I use several blades in that size range, boss. Anywhere from #02 on up to a #5. I have learned, especially on my Hawk, on the smaller blades, a little more tension & and less blade speed, gets the blades to last longer, and really cuts downs blade breakage.

Readin' thru some of what's already been throwed out  there to ya, I ain't able to say as I go along with the wax on accounta I ain't never tried it. Plywood is hard on blades that small, as well as speed. 

As a rule, fretwork is fairly slow, steady cuttin'. 

I've found that Johnsons wax on the blades works better'n anything, an' don't seem to pester any of the lacquer or clear coat I spray on the projects.

 

[Jim McDonald]

Les, 

It's been said, but that seems like a lot of wood for not much blade.

And tiny blades break easily anyway.