under cutting

[parksb5]

been working with  a scroll saw for 6 yr i have a dewalt scroll saw use top blades i have a problem with under or over cutting like for cutting puzzles can anybody help me out

[lanemaux]

You have not really made the problem clear amigo. Are you having kerf problems? Or maybe some other trouble. The clearer the question , the more useful the help will be. For example , I don't undercut my puzzles because mine are really simple , as in 4 to 10 pieces. Once the oil finish is applied they tighten up some (No pics on mine, natural wood and a thick quarter inch).

[parksb5]

the puzzle only come apart one way.

[dunk]

  You are either pressing too hard and not allowing the blade to do the cutting or your tension is off.  One other point.  You may be using the wrong blade for the thickness of wood.  Softer woods can be done with a #3-#5  harder woods may require you to bump up to a #7.  Take your time and allow the blade to do it's job & no side pressure.

[tbolt]

Make sure table is square the. Practice cutting shapes on similar wood till you get it

[lanemaux]

The undercut on one side would mean a corresponding overcut on the adjacent piece assuming that you are using a single blank then. Not a problem I ever considered much. I'm a fairly simple guy you see. Does not the introduction of multiple direction cuts cause situations in which pieces coming together with 3 or more joins to each other sometimes cause conflicting undercuts? This would mean that some pieces could  only be fitted from below , or am I missing something? Sorry if all this sounds dumb , but I find myself genuinely confused here.

[Danny]

I have cut MANY, MANY puzzles.  When I first started I had problems.  Asked here and was given directions.  Now I cut
like a pro.  LOL  Simple test for having the saw table top square to the blade is the cut test pieces.  If all is square each
piece will come out either direction very easily.  If your test and they do not then readjust the table.   

Hope this helps.                Danny  :+}

[DWSudekum]

Actually since this is a puzzle I do not see the issue.  Having cut several puzzles so that you actually had to build groups and put some in from back to front some in from front to back makes the puzzle that much more challenging.  The only way I know of to ensure that everything fits correctly front to back or back to front is practice, make sure you blade is sharp and your table is square.  Other than that have fun.

DW

[Rapid Roger]

Just a suggestion on making sure the table is square to the blade.
I usually use an old credit card for a square to check it but, if you have a doubt.....Use a 3/4" or thicker piece of scrap and cut a straight line into one edge a short distance (1/2" to 1") and then use the piece with the cut and slide it  back into the blade from the back side of the blade. If it goes in smoothly, you are good to go but, if it doesn't align very well then your table is not 90 degrees to the blade so move the table slightly and do it again.
Just a couple of quick, easy, cheap, hints for sit-up time. Hope that helps you some time.

Rog

[Dakota Saw Dust]

Once you know the blade / table are square there are a few things to look for. The size of the blade used needs to match the tightness of the turns. I started using to large a blade for my turns and found I could not keep on the lines and if I forced the turn the bottom cut caused the parts to only fit one way. Then I tried a smaller blade which followed the lines better but was to thin a blade and bowed cutting 3/4" stock. It's a tricky balancing act; the right blade for the wood thickness/hardness and slow the feed rate down so the blade does the cutting. Don't slow the machine rate down. I don't do puzzles on a regular bases because I still haven't got things down pat.  I think my present problem is not changing the blade often enough and then I start pushing to hard for the turns.  Good luck   Brian