Osage splitting when heating

[Marc St Louis]

I had some 20 year old Osage do some very odd things while heat-treating it several years ago.  The belly started roll and bubble as if it was full of water leaving cracks that ran deep into the wood, ruined the bow.  I've been very cautious with Osage since then

[JonW]

I had some 20 year old Osage do some very odd things while heat-treating it several years ago.  The belly started roll and bubble as if it was full of water leaving cracks that ran deep into the wood, ruined the bow.  I've been very cautious with Osage since then

I had the same thing happen on the Osage bow that I'm currently working on. I don't think mine is ruined though. This stave even buckled on the trimmed sides when I heated it. It had been cut four years ago and been stored inside the house for the last two years.

[George Tsoukalas]

I use my moisture meter all the time. I keep checking right until I string it up for the first time.
Sometimes I still get surprised.
Jawge

[sleek]

I have had wet ones crack on me when recurving or heat treating. Never a dry one. Also I have never once sealed the back of any stave fresh cut or not. Just the end grain.

[Hamish]

When I used to dry heat osage  I sometimes got cracks, especially with really old osage. After I started to use vegetable oil with dry heat I haven't encountered the problem again.
 I also used to use shellac on the back whilst seasoning, but I found that the shellac seemed to seal in the dry heat/moisture so much that it had to explode from the build up of pressure internally in the cells. No cracking on the belly side that gets the heat but many tiny fissures on the back, hard to see unless you get up close.
 So now before I use dry heat, I either scrape off any shellac, and coat the bow in oil, no problems anymore.
 Hamish

[Dances with squirrels]

I think in this discussion, we need to clarify whether we're referencing heat TREATING the belly, or heating to change shape, as I think there's a big difference in the two techniques and how each of them can affect the wood.

[Pappy]

I have had that happen from time to time, Like marc I am very careful with Osage now. My rule if it is less than 2 years old I steam first and then heat if needed, older than 2 I just heat. I always seal the back and use cooking oil while heating. I had a run of that a couple of years ago ,probably as Pearl said moisture, it was a wet year but I figured it wasn't that much trouble to seal and oil so I do that all the time now. No problem as of late. Usually the cracks caused no problem, ha that's what snakes were made for, hide the flaws.
  Pappy

[MWirwicki]

Like most of us, I experience the same cracks from time to time.  Our humidity is a bit higher here in Michigan though.  I fill with super glue and continue on with the bow.  I too steam 2 year or under wood; usually backed up with a heat gun to keep it hot during my tweeking.  Dry heat on older wood. 

I would be weary about leaving the bow in a hot car.  I've seen some osage return (to some degree) back towards its "original" state when exposed to excessive heat after corrections were made.

[Badger]

  Matt, I plan to do a lot more steam work with osage than I have in the past. I have gotten more than my fair share of cracked limbs when recurving, my own fault I know but I have a better success ratio with steam on recurves.

[mikekeswick]

Steam everytime for me with recurves too.
Badger - california...50% rh....8% emc....sunshine....over a 1000 osage bows! Well I'm jealous even if nobody else is!
Newcastle....70 - 90% rh....13% emc....rain/cold....about 10 osage bows.....

[Badger]

Steam everytime for me with recurves too.
Badger - california...50% rh....8% emc....sunshine....over a 1000 osage bows! Well I'm jealous even if nobody else is!
Newcastle....70 - 90% rh....13% emc....rain/cold....about 10 osage bows.....

  Mike, I was exagerating, probably 1/2 that many osage bows would be more accurate.

[crooketarrow]

  I'm no where close to a 100 bows like BADGER but I have biult over 100.

 But I've cut and sold a 1000 other staves.

  I also after ruffing out my bows. I've never resealed any and it's been a year for a couple before they got finished. As long as their in a dry place there good.

  I quit useing heat on moveing parts long ago. I do bend handles and tips if I need to. I've mever seen any cracks doing this.

 But for lots of bows. I ruff them out green and but them on caul. To get the tips,handle inline. To be finished when I need it.

  Alot of the others I'll ratchet strap them down beteen saw horses while green to add reflex.

  I also have a lot just straight staves. Give me a PM if anyone needs a stave.

  Only reason I can thing of is your stave had a small amount of moister. Or it could be relitive hummity exspecially if you live where theres high hummity. But I've never seen this and there was a time when I heated quite a few osage.

  Thats why there small cracks because theres only a small amount of surface moisture.

[sleek]

Just had a 5 year old light yellow stave send out many longitudinal cracks while heating to bend. Its dry for sure but cracked under slow heat. Not life threatening but annoying for sure. Heat was on belly, cracks, belly to back.