# Do the math...

Okay, so first off I’m no mathmagician - that said, I hear shapers throw around the terms “did the math” or “did you write your math on the blank?” etc… I’m a new shaper and I’m not formally trained, also I’m atrocious at math. I’m sure I’m not the only one on here who’s still green enough to be completely confounded by these concepts. I’ve scaled up my shapes before, but only done so by eye with a shapers square and a swing template. So let’s start a thread to help all us under-educated folk out with this one… what is this “math” you speak of, and how does it relate to your shapes? What equations are you using for your rails, thickness, fins, etc… and what tips can you give to those who are trying to get into shaping, but missing this apparently very crucial bit of knowledge?

Shushk,

I was horrible at math in school. Shop classes were my thing. My shapers math consists in adding or subtracting measurements in increments. I hand shape all my boards. So to consistently produce all my models, I have several sized templates for my most popular models.

I have them in 2" increments. So I make them from a known template. I start by adding 1/4" to the width for every 2" I go up or down. The nose and tail @12" I add or subtract 1/8"-1/4". I’m trying to keep the same outline curve throughout the series of templates.

The rails I use a chart I made for rail thickness when the rail is still square before I cut my rail bands. For example, for a 2-1/4" finished thickness board, my rail thickness is 1-1/2". For each 1/8" thickness, whether up or down, I just add or subtract the 1/8" or so.

When you have multiple templates varying size for the same model, you can stack them from small to big and see the same basic curves.

For me, that method works. It is just easier than trying to stretch or shrink a template too far. The outline seem to get distorted.

When I build several sized boards all the same model, put in the rack. They all look the same. Almost like they came off the machine. Aaarrrrggg. I said the “M” word.

Well, that’s my “Shapers Math”.

I’m sure there are other methods.

My math teachers would be so proud.

Barry

Oops.

Double post.

Sorry.

Is this place moving slow for you too?

Barry

back yard.....no Math.

Rulers and curves. Lines and cross hairs....Gut feeling...go for it!

String, batton, fishing rod, straight edge, masking tape.....

Its all in the radius of the curve

For math, I use a computer.

If I want something calculated, I program it.

I never want to calculate something twice, unless it is dead simple.

And in the end I share my code.

Like the pro shapers share their knowledge around here. I highly appreciate the spirit of sharing on this forum!

Also big thanks to haavard & co for sharing their boardcad code.

2 hands one planer??

Shaper's Math......What?

L x W x T = Board size

Shushka see PM

Math hurts my head.  Thats why I have a very smart wife.

Where is malaroo these days?