Math help for endgrain butcher block

[Brian Penning]

What can I say -I suck at math and will continue to do so.....:o
Making a 24" X 48 " endgrain butcher block top 3" thick for a kitchen island.

How long should the initial 2" thick slab of glued-up long grain boards be so that when I cut them every 3" (then rotate the 90 degrees) I'll end up with my required 48".
Don't forget the saw kerf loss either.

I think I need 75" but I'm not sure....

[Scott Hildenbrand]

If you need them to be 3" thick, making cuts on 3" thick material, you'll need it to be a smidge over 48" long to make up for the kerf of the 16 cuts required.

49" should be more than enough.. 50" if you want to be safe.. Besides, you'll have to make a cleaning cut on the first end.

EDIT: You're not loosing any width by rotation if you're making 3" wide cuts on 3" deep material. So turning it, you'll have 3" no matter where you're gluing.. If you understand that.. ;)

EDIT 2: Argh.. I miss read that the starting thickness is 2"... Sorry about that.. :D For what ever reason I was thinking you're working with 3" thick wood.. :( Aw well.. That'll teach me to read everything.

[Brad Wood]

There is a program that was written for help to design cutting boards. Google "cbdesigner" the first "hit" will take you to a place where there are download links... I think mirror3 is active.
The guy that wrote this seems to have trouble finding a reliable site to host the download.

you might get dll or ocx error when you run it (it doesn't require a installation).. that site also tells how to address that (easy).

I'm actually going to try to contact the guy and see if he minds if I host the file for him. If you have trouble finding it, let me know and I'll email it directly to you

[Walter Plummer]

I think your math is close but allow a little more. I think you calculated as follows? 48" divided by 2" layers = 24 three inch cuts. 24 ( 3"+ 1/8" kerf )=75". As stated above there would be at least one more kerf to start with. I would go with at least 78".;)

[Chris Tsutsui]

Yeah, I would allow for extra so 78" should work. You have to factor in that the long sticks won't be glued up perfectly on the edge and you'll want to cut off that short end before making your cuts.

24 cuts * 3" = 72"

Then add 24 blade kerfs * 1/8" = 3"
Or 24 Thin blade kerfs * 3/32" = 2-1/4"

Can I ask how are you going to cross cut a 78" by 24" panel that's 2" thick?

[Brian Penning]

Can I ask how are you going to cross cut a 78" by 24" panel that's 2" thick?


Er...um....that was my next question? lol

[Rod Sheridan]

Er...um....that was my next question? lol

Sliding table saw would easily accomplish that.........Rod.

[Kyle Iwamoto]

Just curious, why do you want your table that thick? 3" of hardwood will weigh a LOT. It will require much less wood if it were an inch thick.... Duh, yeah, statement for the obvious. You can make a 3" skirt and a 1X2 frame inside for support.

You also don't need to make all of the wood into 1 continuous 78" length. You can make it in 4 20" long sections..... Easier to cut if you don't have a slider, like most of us.

[Chris Tsutsui]

I think an easier kitchen island to make will be 2"x2" bars going lengthwise to make up the kitchen island.

Then if you want a butcher block to act as a chopping block, then make a small one that's endgrain and 3" thick.

I've made end grain maple butcher blocks and it's hard enough making a small one FLAT on the top. Then out of 3 that i made, one of them started to split at a glue joint after several months of abuse. For glue I used Titebond3.

[Faust M. Ruggiero]

When you say a "butcher block top" I assume you are orienting the end grain as the finished surface. If so, and you are making a 3" thick butcherblock top and using 2" square stock to do so. Your top is 24" X 48". You will need 12 X 24 = 288 pieces 2" X 2" X 3" long. You will need 72' linear feet of 2" X 2" stock plus a little for waste. How you get that will depend on the length of your boards. There are tricks to putting together a butcher block top to allow for the slight "out of square" that will multiply as you assemble so many pieces. Have fun.
fmr