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Building Tips and technical articles. => Building techniques => Topic started by: Geoff Goodworth on November 13, 2015, 08:22:04 PM
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The blade on my scroll saw—a fairly cheap yum cha model—wanders seemingly with a mind of its own.
I've tightened the blade almost as far as I dare but it still wanders.
Does anybody have any suggestions for getting it under control?
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What are you trying to cut. My old Dremel I've for well over 40 years likes a new blade to cut hard wood. Of course there is no tension adjustment on it either. Now my Shop Smith band saw takes off if you don't go slow enough. Can't crank tension up too much unless I want to replace blades. Also new blades and good eye does wonders. H^^
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You may be feeding too fast. Relax and enjoy the time.
Check to make sure the table is square, and that the jaws for the machine are not putting a twist into the blade.
Cheap blades wander, they are stamped and do not have tooth set. This means it cuts easier on one side of the blade than the other. The blade will tend to wander in the same direction first. (I threw out the blades that came with my machine for this exact reason, after a certain amount of cursing.) Spend a little more money on high quality blades that are ground and have a kerf set to the teeth. (I do not have brand recommendations, sorry, I am using "brand name" blades from the local big box)
Reduce your feed pressure. Pushing the material into the blade faster than the blade is cutting it will deflect the blade and cause random wandering. Increasing the blade tension may reduce this some.
Switch to a more stout blade. This will mean that there is more blade to work turns around, which will prevent really small radius cuts and reduce wandering.
Make sure your blade is suited to the thickness of your material, or material stack. Make sure your blade is suited to the hardness of your material.
Strong grain structure can cause the blade to follow the soft edge of a hard spot. Back up and cut even slower.
As long as the arm is moving in a "straight" motion (different machines move differently) the machine itself does not cause wandering, unless there is a lot of play in the arm from side to side while operating.
Phil
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Get a wider blade.
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Get a sharp blade.
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Thanks for all the advice. Until now, I've only tried to cut balsa but I need to complete a wing cutout in a 1/2" fuselage plank where I glued in the engine crutch before roughing out the wing cutout. HB~>
You've given me some useful guidelines.
Cheers.
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I'll bet ya dollars to doenuts it a crap blade with no set in it.
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wandering scroll saw cuts are caused by:
lack of blade tension
dull blade
wrong blade ( wider is better)
feeding too fast
cut rate too slow.
not feeding directly into the blade
see
http://www.airfieldmodels.com/information_source/model_building_tools/scroll_saws.htm (http://www.airfieldmodels.com/information_source/model_building_tools/scroll_saws.htm)
http://www.airfieldmodels.com/information_source/how_to_articles_for_model_builders/tools/straight_cuts_with_a_scroll_saw/index.htm (http://www.airfieldmodels.com/information_source/how_to_articles_for_model_builders/tools/straight_cuts_with_a_scroll_saw/index.htm)
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John, there is set on the blade—enough to make the kerf more than double the width of the straight (without any set) part of the blade. The second of Dave's links provides a plausible explanation.
Dave, thanks for the links. I've found the Airfield site invaluable in the past but never thought to look there. Thanks again.