Strange Scroll Saw Question

jillsy · #1 10-25-2006, 10:25 PM

Hi again all,

After all your help from the last thread regarding the band saw, I was wondering if you could help me with my scroll saw?

The whole reason I got the bandsaw was that although my scroll saw is great for cutting around tight corners, I find it very hard to push thru the wood. I decided to use it tonight after *surprise* that bandsaw blade did pop off! And after trying unsuccessfully to put on a new one (I never had that much trouble before, must just be one of those nights) I used the scroll saw.

An hour later, my back and neck hurt and I'm not crazy about the job it did. My question is this: should the wood be so difficult to push forward? It's only 1 inch butternut so I don't understand the problem. The blade is tight and relatively unused so that's not the problem. But here's what I find strange- Cutting against the grain is much easier and faster than cutting with the grain. Shouldn't that be just the opposite?

I drew all my Santas going from head to toe with the grain. Using the bandsaw, I can just follow the pattern, as long as the blade can bend. With the scrollsaw, as I try to cut with the grain, I'm really forcing it (hence, my sore neck and back!!) But, when I'd make cuts from the side, it went much easier and faster.

Am I supposed to be drawing my patterns on the wood so they're against the grain? Sounds strange to me, but after tonight, it seems the way to go.

Thomp · #2 10-26-2006, 12:30 AM

jillsy,

i have 2 scrollsaws, and no bandsaw, but bandsaws are generaly more agressive as there is more teeth per second going through the wood,

cross grain cutting is faster with the smaller teeth of a scrollsaw,
if you slow down the cutspeed the saw will nearly stall, i have to remind myself to speed up across the grain cuts especally on 2 inch basswood..
theres not an option of changing blades from fine to corse when changing grain direction like when using hand saws
but if you remember a finish or crosscut saw is fine and a ripping handsaw has rough teeth..

i just aligin the pattern with the grain for strength, longest parts or parts that are frail should be supported by long grain supporting them, things like arms hands and fingers should have the grain running through them like the bones in your hand.
a cross grain situation in its self could make arms break and fingers fall off at a whisper of effort.

its a trade off....
some items should be made of a different section like arms, then attached with pin and glue.

hope this helps
thomas

AlArchie · #3 10-26-2006, 07:30 AM

Even with a bandsaw, cutting across the grain is generally easier than going with the grain. Heck, even a chainsaw will be slower cutting with the grain. Why? It's not just bigger teeth used for ripping, it's a whole different tooth pattern.

Saw teeth ground for crosscutting have teeth with the forward edge ground with the bevel toward the inside of the kerf, and set toward the outside. One to the left, the next to the right, and some blades have a "raker" tooth in between to break out the chip.

Saw teeth ground for "ripping" or cutting with the grain usually have fewer teeth per inch (larger teeth) but they are also ground straight across the top, like a straight chisle. They are still "set" one to the right then the next to the left, but cut an entirely different type of chip.

A crosscut ground tooth cuts like a skew chisle while going across the grain, slicing those fibers cleanly. Going with the grain, they slice the fibers lengthwise, but don't sever them so they tend to jam in the gullet.

A straight chisle tooth, rip filed blade severs them the same way a straight chisle cuts while going with the grain, and gets those shavings out of the kerf.

If you look at the shavings, or "sawdust" from the two different cuts, you will see that the dust from a crosscut is made of fine chips while the "dust" from a rip cut made with a rip saw actually looks like fine shavings from a plane or a straight chisle working with the grain.

Most "general use" bandsaw blades are multi-purpose, but are ground as Cross-Cut" skewed teeth, while "resaw" blades, used mostly for cutting with the grain, are ground with the chisle tooth pattern.

There are even special chains for chainsaws that are to be used for ripping lumber, or cutting with the grain. They have specially ground straight teeth with very aggressive rakers.

Probably more than you wanted to know..............sorry.

Al

jillsy · #4 10-26-2006, 08:38 AM

Thank you both, I do appreciate it. At least I know there's an explanation besides, "Jillsy, you goofed!"

Thomp · #5 10-26-2006, 09:50 AM

i agree al,
your explanation is right, guess im getting so old im loosing my learning....

sorry if i lead you astray jillsy..

AlArchie · #6 10-26-2006, 10:04 AM

You didn't lead her astray, Thomas, you just gave her the "short version"!

I'm afraid I tend to (how's Bill O'riley put it?) BLOVIATE!

Al

Thomp · #7 10-26-2006, 10:32 AM

Al,
I can feel jillsy's plight with her wood hobby nagging on her "needing a sawdust fix", and her baby's hanging on her leg, and thought she might need an answer as fast as possible, i know how them mommas are about to go over the edge and the least little thing can push them over AL,.

I wish i was a good cartoonist i think the mental vision of jilly's daily plight would make a great carving in the AL cap sniffy smith mode "Maw & Tater" ,,

mentally pitcure' a kid hanging on each leg one pulling the dress tail, one climbing her apron strings, and her holding one in one arm and with the other arm she is trying to scroll something difficult,
the look and expression on her face would be of her tongue sticking out one side of her mouth and squinting her eye on the opposite side, sweat drops in the air and all the speech bubbles saying maw, moma or WAAH!,
now of course it wouldnt be complete without through the entire scene there would have to be a clothe line full of baby diapers hanging to dry... and her neary tangled in them

I envy her stick-to-it-ness & perseverance.....she is commended ... shes got the wood bug bad as i do.... HAW~!

cerndog · #8 10-26-2006, 10:33 AM

Hey guys,

I hate to jump threads back to the bandsaw question, but did anyone recommend relief cuts? These are cuts coming in from the outside, right up to the pattern line, perpendicular to that line, about every half inch or so. That way the saw is only cutting a half inch of material at a time and the blade doesn't bind up. A good bandsaw (or scroll saw?) should cut curves without them, but they may help until the blade issue is solved. My small bandsaw is not the best, so I use these to relieve stress on the blade and on myself!

AlArchie · #9 10-26-2006, 10:41 AM

That would make a good caricarture scene, Thomas!

And Dog, I never thought of that.....seems like a great idea for easing some of those tight turns! Thanks.

Al

Thomp · #10 10-26-2006, 10:53 AM

i agree relief cuts do make it easier to make the tight cuts with the bigger blades,

But make it a really tough jigsaw puzzle to out back together to cut the other side.. when doing a 3d or compound project. because of all the kerf's removed the other side view pattern will shift causing other problems with alignment.

i guess its a 50/50 venture.

becuse i dont have room for another tool like a benchtop bandsaw, till i get a bigger place.
i know its expensive but i cured all my bandsaw blank problems, i draw the pattern on the blank and take it to a cabinet shop where the owner cuts them out for me for $5.00 each, that's only for stock i cant handle on my scroll saws... plus im getting him hooked on the idea of carving some of these caracatures,,