Calculating BF used to make a cutting board

[Keye]

A couple of weeks ago I had a post about the Cutting Board Designer JS.

I have never really paid much attention to how many BF it takes to make a cutting board. Now that I am using the Designer JS I am in shock about how many BF are used. My wife asked me to make boards for her to give away for Christmas presents. I made a bunch. I just calculated I gave away over $1,200 in wood alone.

I figure the cost of each board, only the wood, was between $75 to $100.

I am going to need to have a talk with the wife when she returns from having her hair done. She loves showing pictures of the boards I make and then asking if they would like to have one. I an sure her hair dresser will have been promised one when she returns.

 

[Pointfiveone.5]

when I include WC (wife's commentary) in my Bd/ft calcs I often find that I could getting more on return if I include her in the bargaining... maybe worth a try...?

otherwise - let us all know when you feel like giving away that much lumber again

 

[creasman]

I figure the cost of each board, only the wood, was between $75 to $100.

What wood are you using and what is the size of the cutting board? That seems a bit high unless you are using an exotic wood.

For example, a 12" x 12" x 1.5" cutting board should take less than 2 bd ft, allowing for some waste.

 

[JohnnyR]

I was shocked to realize how much waste you can make with amount of repeated cut -glue- plane-cut -glue - plane etc. etc. that is necessary for a very figured or chaos board, especially if you use an 1/8 blade vs. 1/16 or a band saw. I never calculated it but it seems there may be more wood left on the floor than ends up in the kitchen.

 

[sandfarm]

Don't worry about it.
What she says goes.

 

[DSWalker]

What wood are you using and what is the size of the cutting board? That seems a bit high unless you are using an exotic wood.

For example, a 12" x 12" x 1.5" cutting board should take less than 2 bd ft, allowing for some waste.

This is what I was thinking. Most CBs are probably only a couple BF. Maybe a little more than normal waste, maybe not if you are building a lot of them.

 

[Henry W]

Also - and my situation is very different - I make cutting board from scraps, not large pieces of lumber I have purchased specifically for that. Of course I don't make stacks of them or give them away to my wife's hairdresser etc. So mine are much cheaper - AND I only make sidegrain boards.

 

[bob vaughan]

Some of the multi-glue-up, really fancy cutting boards could easily eat up the wood inventory. At $14.00/BF for retail replacement walnut, that's 6 BF ±. I could imagine lots of crosscutting and ripping could eat that up. If it were 8/4 lumber, that's still imaginable for labor intensive part detailing.

 

[ednl]

No doubt, a board made of exotic hardwood can be pricey. And when you include an epoxy "river" the cost of materials can double !!

 

[Keye]

I am using walnut, cherry and maple. The latest board I am going to make Design JS calculated 16 board feet. The board will be end grain 18"x12". Someone please tell me what I am reading as BF is wrong. It would make me a lot happier to be wrong rather than spending that much money on cutting boards.

 

[creasman]

The board will be end grain 18"x12".

How thick will the cutting board be? At 18" x 12" every inch of thickness is 1.5 bd ft -- not allowing for waste. Assuming .5 bd ft waste (25%) per inch of thickness the requirement is 2 bd ft per inch of thickness. This would give an 8" thick cutting board based on the 16 bd ft calculated. Note, I think 25% is very generous for the waste, but it makes the math easier.

My assumption here is that you are using a simple, rectangular pattern with the blocks. If you are sawing curves or other shapes that would increase the waste. It might help to see the pattern for the cutting boards.

 

[bob vaughan]

I am using walnut, cherry and maple. The latest board I am going to make Design JS calculated 16 board feet. The board will be end grain 18"x12". Someone please tell me what I am reading as BF is wrong. It would make me a lot happier to be wrong rather than spending that much money on cutting boards.

16 board feet is four 1x6x8' boards. 16 square feet is 1/2 sheet of plywood.
That's a lot of wood to make an 18" x 12" cutting board.
Maybe there's a decimal point off or something and that assumes the program is using Imperial rather than Metric.

 

[HMH]

Yeah, there is definitely something off in your software, or likely data entry there - check your units. BF isn't super difficult to calculate manually. (Thickness IN INCHES x width IN INCHES x length IN FEET)/ 12. As a quick example, lets assume your board is 2" thick, and 1" wide, (you mentioned orienting as end grain). That said, each 1" wide strip would be (1"x2"x1.5')/12 = 0.25 BF. Multiply that by 12, (for a 12" wide board), and you'd have 3 BF per board. This obviously doesn't account for waste/ any geometric patterns you may be running, but is a ballpark/ sanity check. As most here said, w/ end-grain boards especially, (assuming roughly 1"x1"x2" blocks), most of the boards I've made, I consider as "free" since, I can raid 90% of the wood I need from my offcut pile. small cutting boards don't use that much wood!

PS - I just reverse engineered your math - I'm guessing that you are mistakenly inputting your length as 18' vs. 18"/12 = 1.5'. Using that logic, a 12" wide by 18 FOOT long cutting board, 1" thick, would be 18bf. you just got your units mixed up.

 

[Alan in Little Washington]

Building end-grain, 3D design cutting boards takes a lot of board feet, especially if you start with enough wood for 3+ boards which is the best and most economical way to do it, (but not that much!) Otherwise you will have too much waste.

 

[Rwe2156]

I am using walnut, cherry and maple. The latest board I am going to make Design JS calculated 16 board feet. The board will be end grain 18"x12". Someone please tell me what I am reading as BF is wrong. It would make me a lot happier to be wrong rather than spending that much money on cutting boards.

A board foot is actually a volume measurement (144 cubic inches).

You will lose some to kerfs and milling but I would think 2 BF would be adequate for one cutting board.

My costs are walnut $10, cherry $4.50, Maple $4. I would guess you’d have no more than $10-12 in a board.

 

[Hjanes]

View attachment 225401View attachment 225402Building end-grain, 3D design cutting boards takes a lot of board feet, especially if you start with enough wood for 3+ boards which is the best and most economical way to do it, (but not that much!) Otherwise you will have too much waste.


View attachment 225399View attachment 225400View attachment 225399

Very nice, Allen. Why not post these pics as a separate thread to show them to more? Regards, Harlan

 

[Alan in Little Washington]

I believe they are posted somewhere on the forum, but I haven't gone looking for them.

I got the design and construction methods from videos by a Russian YouTuber mtm wood. Here is just one example of the many he has posted:

He has some really nice 3D endgrain boards.

He started out in a small home shop, kept expanding, and the last I heard (several years ago?) had a new factory, at least 2 - 3 retail stores, and ships worldwide. His videos were in Russian but had good English close captioning and Sketchup drawings.

 

[Keye]

When I looked at the spread sheet I took the numbers to mean BF They are not identified in any way. One second of rational thought would have made it clear it could not be BF. Just plan stupid. Makes me think of a line from a movie "stupid is as stupid does".

This may be an all tine record for me.

 

[pop-pop]

Makes me think of a line from a movie "stupid is as stupid does".

Forrest Gump

 

[ScottM]

When I looked at the spread sheet I took the numbers to mean BF They are not identified in any way. One second of rational thought would have made it clear it could not be BF. Just plan stupid. Makes me think of a line from a movie "stupid is as stupid does".

This may be an all tine record for me.

Not stupid at all. A simple mistake that we learned something from.