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by Russ Marie - Scroller
Russ is an Illinois reseident and is available for scroll sawing instruction, demonstrations and classes. If you would like to hire him, call him after 6pm (central standard time) 309-446-3509. This clock is just one of the beautiful creations Russ can make with a scroll saw.
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Why Scroll Saws? They are relaxing and quiet, especially after using other noisy shop tools, tablesaws, planers and jointers They use up scraps from other projects They do not require a lot of physical effort, just some eye/hand coordindation and practice. If used with a good dust collection system, it is quiet enough to be used in your house. |
Hand held coping and fret saws
Older jigsaws, eccentric or crankshaft at lower blade chuck moves the blade, top blade chuck tensioned by spring pressure. Blade tension varies throughout stroke.
"C" Frame saws - Rigid "C" shaped arm with rocking action, aggressive on thicker stock, disadvantages are overbite.
Parallel arm saws - two parallel arms, usually the lower arm driven by an eccentric off the motor.
Free arm saws - if blade breaks, upper arm is free from driven arm and stops.
Fixed link - mechanical link between arms at rear, if blade breaks, upper arm continues to move.
Parallel link - (Excalibur, Dewalt) very little vibration blade holders move straight up and down, will not fatigue blade at clamp, disadvantages are short stroke
I would always recommend a variable speed saw. You can usually find a good saw in the $400 to $500 price range (street price).
Clean, polish and wax table using paste wax.
Align blade holders - adjust back-up set screws and clamps
If left handed, some blade holders can be reversed for lefties.
Adjust stand and stool to be at a comfortable height.
Tip rear of saw towards you , this makes for easier viewing of the work area. When you read a book, you usually tip it towards you.
Oil the saw according to manufacturers instructions
Purchase a good light, or a magnifying circle light
Make some arrangements for dust collection or at least set a fan to blow the sawdust away from your lungs.
Spiral - Will cut in any direction, leave a coarser finish, have a tendency to follow soft grain, hard to keep tensioned, useful on large cutouts that would be hard to turn.
Standard tooth - Available in most sizes, on thicker stock, do not clean well
Skip tooth - Cleans well, available in most sizes
Skip tooth reverse - No breakout on bottom of work, have a tendency to lift stock in larger sizes (Breakout is not a problem with smaller size blades and can be prevented by adding a scrap piece to the bottom of work or by gluing card stock to the bottom.)
Double tooth - My personal favorite, cleans well, cuts fast, leaves a good finish and is available in most sizes
Precision ground blades - more expensive, but very aggressive, teeth are ground so there is no burr causing blade lead. From Olson sizes 5-7-9, from Advanced Machinery (Hegner) sizes 3 and up.
Crown tooth - from Olson, not too aggressive, can be reversed, works well on plastic, needs to feel sides to find burr to adjust for blade lead.
Woodrunner - from RBI, mildly aggressive
General Rule - Use the largest size that will enable you to make the turns required in the pattern, and still leave the desired finish without sanding.
Most beginners do not apply enough tension to the blade, making it hard to follow the pattern. Following the instructions in your owner's manual will usually result in turning the blade to a high "c".
Thicker stock good for beginners, makes the saw work harder, making it easier to stay on the line.
Use scrap from other projects and for practice
Most hardwoods saw sharp and clean
My favorites are cherry and walnut
Thin stock can be obtained by resawing on the table saw, or better yet, on a bandsaw using a re-saw blade and a guide block or fence
Thin plywoods are available form several sources
Books, craft magazines, catalogs etc. Most pattern books encourage you to photo-copy patterns
Self service copying machines. You will usually have both 8.5" x 11" and 11" x 17" paper.
Most copy machines can enlarge and reduce
Tracing paper
Pantograph - easier to use if you enlarge or reduce in small steps
Useful tools - Proportional scale, this will tell you what percentage to enlarge/reduce to reach desired size, small drafting templates, angle templates, circle templates, French curve set. These will help to true up lines distorted in copying.
Rubber cement and glue sticks are great for small patterns
Spray adhesive - better on larger patterns, but messy. It is best to spray back of patterns, wait 3 - 5 minutes, then apply.
Keep a light touch on the work piece by just holding with your fingertips and a little pressure with your thumbs to steer and guide the work.
Blade Lead - on all but precision ground blades. Blade lead is caused by the milling process used in the making of bandsaw and scroll saw blades. Blades are milled from left to right as you are looking at the front of the blade, leaving a smooth edge on the left side and a burr on the right side of the blade. This makes the blade cut more aggressively to the right, making it harder to follow a straight line. After you learn to adjust for blade lead, this burr can be used to your advantage.
When sawing patterns, try to keep the waste area on the right side of the blade. This will leave a smoother finish on the save side of cut and make it easier to turn to the right.
When sawing patterns, push the stock in the direction of the turn and pull towards you as you turn the stock. After making the turn, feed the stock slowly until you pick up the blade lead.
Always try to pre-position your fingers before making a change in direction.
Tight 180º turns are started the same way as the partial turns, just hold pressure on the side and back of the blade until rotation is complete. Then saw out the same kerf.
When picking patterns, try to choose ones with lines that will match the blade size required to follow the pattern. This will make it easy to just remove the line when sawing.
Always look the pattern over and decide how sharp or close the detail should be followed. A simple tots puzzle could have rounded corners and points, while a detailed piece of fret-work would look better with super sharp corners, points and crevices.
Good practice exercises: small squares, circles, triangles, sawtooth lines, long straight lines, long curves and 180º turns.
To keep a long straight line, score left side with marking knife and keep left side of blade along the score line.
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To saw a sharp inside corner  |
Make 2 or 3 passes into the corner using teeth like a rasp to leave a sharp corner, then saw out. |
To saw a sharp point |
Saw out past the point, make a 180º turn and saw back on line, if the blade jumps or is searching for a bite, stop the saw, push the blade against the line, hold pressure and start sawing. |
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1. Saw into crevice 2. Back out and turn 180º 3. Back into bottom and saw out |
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1. Saw into crevice 2. back out and saw to other side and to bottom 3. Use hole to make turn and saw out |
To saw into a long narrow crevice from both sides:
1. Saw into bottom on left side first, stock on both sides of blade will keep blade on line.
2.Saw down right side last, the more aggressive right side of the blade will make it easier to keep the blade from breaking out as you reach the bottom.
To saw out a circle or a disc:
Use the right side of the blade like a rasp to clean up any bumps left from start.
To saw out a pendant or an ornament start in corner
When starting inside cuts, start at a point or corner
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