Tensioning thin blades, argh....

[Silentbob Junior Member Find all posts View Profile Close Silentbob]

I recently purchased a Craftsman scroll saw and was trying to put in a small blade to cut thin pieces of carbon fiber.

I get the blade in and tighten the holder, but when I try to adjust the tension using the "1/8" rule the blade pops out of the lower blade holder. Is this normal for thin blades? Do I just have to adjust the tension carefully for thinner blades?

So far I really enjoy the saw; it doesn’t make a lot of vibration or noise and cuts very well. Just trying to get this thin blade in correctly and tensioned is very frustrating.

Oh and these are plain end blades.

[jttheclockman Senior Member Find all posts View Profile Close jttheclockman]

Bob

You asked a question and in it there are two things you mention. Something about 1/8" rule. I have never heard this and do not know what you are talking about. You also mention the blade pops out of the bottom holder.

Let me see if I can give you some advice. First you are correct in stating finer blades need a little more finece'. When tensioning you want a ping sound when plucked with your finger. I do not know if there is some sort of scale on the saw but I never use such things. It becomes a matter of feel. As far as the blade poping out there could be two things happening. One whenever you get blades they come through with a bit of oil residue on them due to the manufactoring process. You should clean the ends of the blades with denatured alcohol or even mineral spirits but I like to use acetone. You can also hit the ends with a bit of sandpaper to rid them of the oil. I like to do this to a brand new dozen when I start the dozen of blades then I know they are clean. Also you want to clean off the thumb screw because it too collects oil. Also you want to periodotically sand the end of the thumb screws both up and bottom because what happens with them they get shiny from metal rubbing on metal every time you tighten the clamp. Thus making them slick and the blade can slip. If this is a new saw lots of times the thumbscrews have little ridges on the ends due to the way they were made. You want to sand them flat and I stress flat. Other than that you should have no problems.

I hope this helps. Good luck.


PS what is carbon fiber and what do you use it for???????

[3_M Senior Member Find all posts View Profile Close 3_M]

Hi John,

The 1/8" rule means that a blade should not move sideways more than 1/8". I like what you are talking about. The blade should give a nice high pitch. Some call it a hight C like in music.
The saw being new, you hit it on the head about ridges and oil.
One more reason could be, they just don't put enough pressure on the blade in the bottom clamp.
A good tightened blade should not come loose.

Mike M

[jttheclockman Senior Member Find all posts View Profile Close jttheclockman]

Mike

Thanks for the explanation about the 1/8" thing It has been so many years that I forgot that is the thing that is taught. I gave up on that right away.

Bob,

Mike brings up another good point about tightening the clamps. Make sure your clamps are tight now I am not talking white finger nail tight but firm. These are things you will get used to the more you use the saw.

[Silentbob Junior Member Find all posts View Profile Close Silentbob]

Thanks for tips I'll be sure to give those suggestions a try later today.

Carbon Fiber:
http://www.psrc.usm.edu/macrog/carfib.htm

The product I am cutting:
http://dragonplate.com/ecart/categories.asp?cID=3

Using it to make RC car chassis, not this exact chassis just an example:
http://www.coldfusionracing.com/modu...showpage&pid=6

[jttheclockman Senior Member Find all posts View Profile Close jttheclockman]

Bob

Thanks for the explanation on the carbon fiber thing. I have never used it and looks like an interesting hobby you have there. Sometimes you just can't get the kid out us so don't fight it join them. Good luck with the car.

[goobydoosdad Member Find all posts View Profile Close goobydoosdad]

OK Bob...............R/C cars huh?? I got out of R/C to start Scrolling...........where you from? R/C became too much from the money thing to be competitive week to week. I am gonna build up my shop with wood crafting equipment and I still don't believe I will spend as much as I did on R/C.

[redballjets Junior Member Find all posts View Profile Close redballjets]

I have a Craftsman saw too, model 21610, and was always pulling the blade out of the bottom holder. When I started scrolling last year, I didn't know about cleaning the oil off the blades but I did learn to sand the end of the thumb screw. The sanding only helped for a short time. I tightened the thumb screw so tight, that I stripped the plastic end off of it. I replaced both the upper and lower thumb screws with hex bolts and use a nut driver to tighten them. I lost the "tooless" feature of changing the blades but at least I am not pulling them out of the holder anymore.