Wednesday, May 16, 2018

Shark Scroll Saw Pattern.


SHARK!!!!!   This guy is over 14 inches long. 

There are around 440 shark species. The first sharks appeared in oceans over 400 million years ago. 
They range in length from ~6.5 inches to 40 feet. The whale shark can weigh up to 13 tons. On average they swim a little over 3 mpg but can reach speeds in excess of 50mph. You are not going to outswim a shark. In the wild sharks have a lifespan of  20 to 30 years.

Sharks even have their own week. Shark Week on the Discovery Channel premiered in 1988. It was created by Tom Golden and features shark-based programming. I guess they deserve their own tv show since they are 400 million years old as a species.

What size scroll saw blade should I use?

You will sometimes see charts like the one above that tell you the appropriate blade to use for a certain thickness of the wood. Let me tell you my opinion on how to use these charts.

These charts tell you how efficient a blade will cut for a thickness of wood. If you are going to cut a board in half then the blade suggested will probably be the best choice. The blade will most efficiently remove the sawdust from the kerf and generate the least amount of heat while cutting the board at a fairly fast rate.

The problem is that we rarely use the scroll saw to do a crosscut or a rip cut. We are typically doing fretwork with small interior cuts and tight turns. Trying to make a tight turn with a #10 blade is just not going to happen. Because of this, we will not use a #10 blade even if the wood is one inch thick.

We will choose the blade based on the pattern. If my board is one inch thick but the pattern has small interior cuts I may select a #5 or even a #3 blade if I think that will let me cut the pattern with more accuracy.

The tradeoff is that the smaller blade will not be as efficient cutting the thicker board. I will have to slow my cut to allow the blade to remove the sawdust from the kerf. If I push the blade it will heat up and probably break.

There are times when choosing a smaller blade just won't work. Sometimes the species of wood is just too hard and you need a larger blade with fewer teeth per inch. In that case, the tradeoff is accuracy. 

As you can see choosing the correct blade requires more information than is included in a chart. 

Very few scroll saw artists who use their machine for fretwork ever use a blade larger than a #5. I am not saying that the larger blade do not have their place but it is generally for basic cuts.

All I have talked about in the above paragraphs is the size of the blade. This does not take into account the different styles of blade. That's another subject for another article.