Cutting Lumber Core Ply

Brian Shannon · Post by **Brian Shannon** » Thu, Sep 07 2006, 2:31PM

Any suggestions on Tooling and speed settings for cutting 3/4\" Lumber(Poplar,Alder)Core sheetstock w/ Birch skin?

Brian

Post by **Jason Susnjara** » Thu, Sep 07 2006, 3:49PM

Hi Brian,

I would normally use either a .375\" or .5\" mortise compression tool with 3 flutes. We run anywhere from 600IPM to 800IPM at 18000 RPMs. Material is going to be different from one supplier to the other and these speeds might need to be tweaked if buying from different sheet vendors. Hope this helps.

Forrest Chapman · Post by **Forrest Chapman** » Thu, Sep 07 2006, 4:06PM

Brian,

When you say lumber core do you mean VC or vaneer core because there is a difference. For VC plywood we use a 2 flute 3/8\" comp at 18000 rpm and when the bit is real sharp can machine at 1000 ipm or more.

Forrest

Brian Shannon · Post by **Brian Shannon** » Thu, Sep 07 2006, 4:25PM

This is a solid(1/2\" of solid strips at random widths) lumber core. It(the core)actually looks like a Luan. I've seen it with a poplar core also. This is for several Blackjack Tables for a friend(I wonder how much time and $ I'll loose on this one) that has a casino equiptment rental business. I am thinking that maybe an Ultralite MDF may be the way to go but he is thinking of the lumber core mt'l.. I worry about it's durability. These will be painted. Any suggestions?

Brian

Brian Shannon · Post by **Brian Shannon** » Thu, Sep 07 2006, 4:33PM

This nests better on RN with nest angle set to 5 degrees. I actually get 30 Tables from 27 sheets. There is a 1\" ring cut from around the main table(the middle offfall is the table. I can't get it to nest that way so I will have to cheat by cutting only the ring, then returning the table to the router to run my 6 holes and rectangular cutout. Any other way that you see? I'll really need to tack these parts down before I cut through the skin!

Brian

Brian Shannon · Post by **Brian Shannon** » Thu, Sep 07 2006, 4:35PM

Oops! the .jpg

Michael Kowalczyk · Post by **Michael Kowalczyk** » Thu, Sep 07 2006, 7:16PM

Hey Brian,

I would use 18mm Russian Birch myself. Those thin curved parts for the top borders may not make it from the CNC table to your assembly area. Lumber core is nice for wide areas but I would not trust it for what you are doing.

I would also see if you can get a better nest by trying several options of nest in X or Y and also change from true shape to cut line while nesting from X and then from Y. I have saved many sheets this way.

If Ecab can not nest it efficiently, then draw it in BC and nest it separately for those parts only.

just my 2 cents,

Brian Shannon · Post by **Brian Shannon** » Thu, Sep 07 2006, 7:37PM

Michael,

Thanks for the input. I may try the birch. I'll check the nest on 5'x5'mt'l. My friend is a tight wad(tight-ass) so he may not want to pay for the Russian Birch. I've tried every way to nest with eCab but had the best luck with RN as eCab will not turn parts at an angle(will it?).

Brian

DanEpps · Post by **DanEpps** » Thu, Sep 07 2006, 8:32PM

It will if you change the grain to say 45 degrees.

DanEpps · Post by **DanEpps** » Thu, Sep 07 2006, 8:36PM

After I shot my mouth off I thought I had better prove it

Rick Palechuk · Post by **Rick Palechuk** » Thu, Sep 07 2006, 10:12PM

Hey, even if you turn the grain your still going to have an area of weakness with that product, go with the Baltic birch.

Michael Kowalczyk · Post by **Michael Kowalczyk** » Fri, Sep 08 2006, 5:30PM

Brian,

I would tell your friend that he can pay a little more for the right material or pay you to make some more tables in a few months when these fall apart and that would not be because of your workmanship. \"\"Inferior material for application\"\" If he plans on moving these in and out for portable parties it's a slam dunk for me that Russian birch is the way to go. Light weight and superior strength.

You can also make this material with a special notation in the sheet material section and just uncheck the grain box. You said this is going to be painted. leave grain for the ones you want to follow the grain and no grain checked for the others. If these are card tables won't the be covered with felt and have a padded armrest on top??? Just a thought.

have fun,

Brian Shannon · Post by **Brian Shannon** » Sat, Sep 09 2006, 11:16AM

I agree with you Michael. They should be R. Birch. I did uncheck the grain on the exhisting material because all will be covered or painted. It only shows in RN at the machine. I wonder if Maranti would hold up. It is much cheaper than R.Birch. In the long-run though....After all this damn design work, I should put the tables in \"Design Sharing\".

DanEpps · Post by **DanEpps** » Sat, Sep 09 2006, 12:05PM

Hey, if your friend is so cheap, make them out of 1/4\" lauan

. It's lightweight and cheap. Put a stiffener under the tops and he is in busniess. When they break after each use he can collect the deposit (equal to the cost to build a new one) and you get another \"job\"

Brian Shannon · Post by **Brian Shannon** » Sat, Sep 09 2006, 1:17PM

Great idea Dan..... Easier on the cutters too! Hah!