Heat treating vs trapping

[sapling bowyer]

The title says it all. Which one is better?

[Del the cat]

Depends on the Bow and the Wood...
Elm Warbow... use both
I don't heat treat as routine... to me it's the Ace up my sleeve if I need to find a few pounds or stiffen up a limb or get some reflex to hold in.
It's about having all the tools at your disposal and using them wisely.
Del

[nsherve]

What is trapping?

[Badger]

  Not really an either or type situation, two different processes. The only bows I slightly trap are English longbows. Most selfbows are crowned which is naturally trapped.

[Loope]

nsherve,

Trapping refers to making a trapazoidal shape.  "Trap the back" could be said "trapezoid the back".  In other words, if the back is more narrow than the belly, then the bow limb cross section is shaped like a trapezoid.

[k-hat]

nsherve,
Trapping is taking a bow with a rectangular cross-section and shaving the corners off the back of the bow to give it a trapezoidal cross-section(hence the name).  It makes the back narrower than the belly.

As i understand it, they both serve a similar purpose....evening the stresses between the belly and back of woods that are tension strong and compression weak.  Trapping essentially reduces mass without reducing draw weight (or not by much) and allowing the belly to have more wood to handle compression.  Tempering is kind of opposite in a way.... increasing compression strength of belly which also adds to the draw weight without adding mass.   Seems like somebody on PA (who had a lot more experience than me with both) felt they both accomplish the same purpose.  In a way i guess they do, but i can see some designs being more favorable to one or the other.  I've used both, but mostly tempering.

Seems like this discussion may have been had before

[Pat B]

You can also trap belly to back if necessary.

[KS51]

If you are making a backed bow, trapping is typically your only option.  I know some guys have done belly heat treating on backed bows but I suspect the type of glue used for the backing has to be considered.

[Jodocus]

I'm very much in favor of trapping. It can be controlled quite precisely, corrected in both directions. Plus, it doesnt leave the ugly blotty burnt pattern on the belly.  Just my taste, though. And I should also say that I'm not very concerned about getting the last 3 % of performance out of my bow, so this is not what makes my decision.

[Del the cat]

... it doesnt leave the ugly blotty burnt pattern on the belly. ..

If you clamp side cheeks to the bow while heat treating, it spreads the heat and vastylr reduces the blotchy pattern and also speeds up the process and helps prevent heat getting to the back.
Del

[sapling bowyer]

Del, What are side cheeks?

[Del the cat]

Del, What are side cheeks?

https://www.youtube.com/watch?v=kM1_A2A0_TI
There ya go...
Note in the video I have a fish tail nozzle on the hot airgun, it all helps to get the heat where you want it.
Del

[Jodocus]

Thanks Del, I'll do so if I ever get to heat treat a bow!

[sapling bowyer]

Cool technique Del, I also realized that you were Derek Hutchison and I saw some of your hazel bows on your google site. Cool bows! Planning to make some out of hazel myself 

[rps3]

I have plenty of wide flat staves, so I do both. Cant say for sure how much trapping has helped, but even though it is so time consuming, I would never not heat treat a  bow again.