When to use a spiral vs a flat blade?

[CNLNC]

OK, i'm about to attempt my first portrait style project. I'll be using 1/8" Baltic Birch and probably stack cutting 2 to 3 pieces. To date I have only used regular flat blades, but I do have new spirals from Mike waiting to be used.

My question is when do you use the spirals for a portrait, vs using the flats for the portrait? I ask because I've read some people using either type blade for portrait style work, but no reason why one over the other, except maybe for personal preference.

I'll be in the shop practicing with the spirals to see if I get the hang of them, anticipating all of your wonderful advice and guidance. This project will be a gift so i want to do it right. Thanks ahead of time for all your input.

[mrsn]

Spirals work well for protraits because you don't have to turn the work piece. Typically if I want to use a spiral for a portrait I use it for the whole piece, just to keep all of the cuttings looking the same. It is a little harder to get a real sharp corner with a spiral, for example if you switch back and forth you may end up with some smooth grass and some sharp grass in your picture.
I will switch to a flat blade if there is long straight cut, like the outline of the frame. I just am not good enough with a spiral to make that look straight.
my 2 cents
MrsN

[GrayBeard]

Katie hits it on the head! (with the cute hammer no doubt)

I cut most of the pattern with the spiral and only switch to a #3 Polar when there are long straight or gently curving cuts to be made.

~~~GB~~~

[julief]

I generally stay with the spiral throughout the portrait.

[RWEC]

And there you go. Everyone finds their own path.

I find spirals hard to control and only use them when the work piece is too big to swing on my saw. Not often as I really don't do big stuff much.

Randy

[Kepy]

I'm with you Randy.  I won't use spirals unless there is just no alternative.  I have only done one project that they were necessary for.  Flatblader all the way!

[ChuckD]

If you don't use spirals you have a great tool in your tool box your not using.  All it takes is a little practice and you will wonder why...