Stack cutting

[JessL]

I wanted to make ornaments with this pattern and thought why not save time and stack cut them like so many others do. I think I'm doing it wrong....

I screwed 3 pieces of wood together. 2 are a 1/4 in and 1 is a 3/8 in (which is on the bottom). Because some of the internal cuts are so small, I have to use a small blade. I've tried several kinds from 2/0 to 3. The top boards seems to look fine but the bottom board is a mess and I have to put up a serious fight to get some of the cutouts cleared.  I'm thinking the bottom board is the culprit. Would appreciate any advice on the topic.  Thanks

[Scrappile]

7/8 thick maybe too thick... I have never stack any thing that totals 1/2" thick and maybe your wood is too soft for cutting that thick.  That would be my thoughts. Other do cut thicker, they may chime in.

[Denny Knappen]

I agree with Paul.  Another thought is the blade square to the table?

[kywoodmaster]

Are all of your the same species?  I have cut 3/4 in with a 2/0 blade many times. If the wood is not the same the difference in the hardness will make a huge problem.

[Dak0ta52]

Paul (Scrappile) has pretty well nailed it. I typically stack cut everything I do except names. I've found that you have to be very careful about "pushing" too hard into the blade and definitely don't want to deviate left or right. The blade arcs from the pressure and while it is cutting along the line of your pattern perfectly on the top piece, the bottom of the blade is still bent and hasn't "caught up" to the top of the blade. One thing I do to help is make sure I cut slowly, especially on curves in the pattern, and I'll completely stop feeding into the blade when I reach a corner or sharp turn in the pattern. That allows the blade to catch up to the top where you are following the pattern. I also rarely stack cut over 1/2-inch. Good luck

Edited April 17, 2023 by Dak0ta52

[JessL]

I am using Alaska birch which is considered a hard wood, as far as I know.  The table is squared up (I actually remembered to check that. haha). 

[Bill WIlson]

I believe Rodney hit it on the head.

Cutting thick/hard stock with small blades often leads to pushing sideways when trying to steer the blade around curves.  This will result in a bowing of the blade that will cause the cut to be out of square.  Your table may well be perfectly square, but pushing & bowing the blade sideways will cause the same type of problem that an out of square table would.

[JessL]

Thank you so much.  I probably am pushing the blade to much.  I'm cutting like I would a single piece, just moving along pretty as I please.  Yikes.  I will finish this one with the 3 boards and try the "slow down and let catch up technique" and see how that goes.  The next one I do I'll keep it to 1/2 in and see if I do better.

[Wichman]

I am currently cutting 3 (stacked), 5/16" thick pieces (15/16" total) for a double lidded basket. Top layer is oak, the bottom two layers are walnut.

I am using mostly FD Polar #1 blades; the tension on my Hegner is 5/4 turns. The waste comes out smoothly either top or bottom

( the bottom piece looks as good as the top ).

It sounds to me like you need to increase the blade tension.

I use the Polar blades because they are " stiffer " than any other blade I've used and resist bending inside the cut.

While cutting I will pause and let the piece float, this helps me not put side pressure on the blade.

[Norm Fengstad]

I cut a lot of baltic birch and seldom go any thicker stack than 3/4 inch as problems increase.

[tgiro]

What Rodney Said -

I constantly cut 3/4" thick and thicker for my intarsia pieces. If I get in a hurry, I'll find my curves and corners don't fit just right. If I look at the piece from the side, I'll see where the blade warped in the corner and now the side isn't perfectly square - then I have to recut the piece.

Ensure your blade is perfectly 90º and slow down in corners and curves.

[BadBob]

I cut up to 1-1/2 inches thick with no problems yet. I have cut 2 inches but I didn't like it. It is too easy to get my finger mashed cutting 2 inches. If it is above 1-1/2 inch its a bandsaw project.

[kmmcrafts]

I typically cut my ornaments in stacks of 4 pieces of 1/8" BB ply or 3 pieces of 1/4" solid core ply, or solid wood. Usually on solid wood I plane it down to 3/16 and do stacks of 4 depending on wood type sometimes just 3 pieces. I used to do 5 and sometimes 6 pieces of BBply depending on the situation at hand but I much prefer doing 4 pieces. Years ago I started out doing 6 BBply in a stack to maximize production and I never did anything more or less than the 6 until I came up with a custom order for 8 ornaments. I normally cut all my blanks back then at 8 x 8 inch and could get 4 - 5 ornament sets out of the blank. That custom order for 8 pieces made me do a stack of 4 so I ended up cutting 2-3 more times on that blank of other ornaments and the cutting seemed to go way faster than cutting 5-6 stacked.. That was my comfort zone from then on so I've kind of stuck with stacks of 4 unless I have some odd number of ornaments I need to make where doing a stack of 5 or 6 makes more sense. 

[JessL]

Wow, thanks again everyone!  Really great info here.  I finished cutting out the one I started and just don't like it. I'll be trying all the same wood thickness on this next one and try for no more than 1/2 an inch thick total and see where that gets me.  I'm just using scrap birch I have laying around and I can plane it to whatever thickness I need.  I'll trial and error it based off all your comments.  I'll get this.....  

Thank you so much!!