Lost blade tension on saw

[JRP]

While scrolling tonight I lost blade tension on my DeWalt DW788 20" saw. First time this has happened. It would run fine for about 10 to 30 seconds and then shake and wobble and the blade tension would be gone. Tightened it up and it would happen again. Probably broke about 6 blades in 5 minutes. Any ideas what caused this or what to do? Thanks

[Jr_Ranger]

We have a lot of 788 owners, me included. I haven't had that happen to mine. Hope someone has some answers for you.

[warren59]

Sounds like you are just losing tension because the blade is coming loose and you are not stopping the machine before the blade breaks. If that is the case, sand the ends of the scrollsaw blades with 150 grit paper to remove the factory oils and rough up the surface for more grip. Remove your thumb screws and set screws and look at the faces of each. They should not be shinny. Sand the flats on the screws with about 120 grit paper, do not round over the edges. Put the screws back in making sure the blade will clamp in the middle of the blade holders. That will fix your problem, I hope.
If the blades are not slipping you have major problems inside the saw.
Good Luck
Warren

[keystonecop]

check that the top an bottom screws that hold the blade are in the center and that the blade is all the way to the back at both the top and bottom.

Now my wording may be off.. but there is a set screw on the left.. make sure it goes about half way out to meet the blade. The Thumb screw should meet the blade in about the center. both top and bottom.

again.. maybe some one can help word this, but the blade will work its way loose if not centered on the set screws and the thumb screw.

[Grandpa Grizzly]

Take the black cover off at the top of the saw where the switch is and there is a screw that goes down through the tension mechanism that has come loose. It takes a torx head if I am not mistaken. I had the exact problem after 8 years and that fixed the problem. Easy fix. If you have more problems just PM me and I will take mine apart again and give you more precise instructions. jmlstudios@frontiernet.net
Grandpa Grizzly

[tomsteve]

while yer roughin up the blade with sandpaper and iffen ya dont do it already, try puttin a bit of a point on the ends of the blades. this helps to thread the blade into holes.

[JohnB]

G'day JRP,
You aint gonna like this one.
I really hope it is one of the other problems mentioned.
I had the same problem with my Yella Machine. There is a tension rod that goes from the tension control lever down through the upper arm end screws into a metal block at the back of saw.
The threads in the block stripped on mine

[bearfretworks]

I think it was Marsha who solved this problem (stripped threads) by having a helicoil installed. One of my 2 yella saws is almost in need of ths fix.

[EMMITT]

I am hoping all that is needed is the simplier methods JRP, but it also looks like you have some good instructions to follow if those don't work.

As for me, if I take that cover off, I might as well put it in the shop. I get fustrated real easy working on things I don't know anything about. The next thing you know I would have a hammer in my hand threatening that saw. lol
Emmitt

[Ramjet]

JRP . If you have the manual for the saw take a look at the schematic . It will help to see what the others are referring to . LOL
Roger