How thick are your limbs for common wood bows 40-50#?

[willie]

Do you guys run a humidifier in your house or HVAC unit? just curious what you measure humidity with? not all hygrometers are equal, some have very limited ranges where they are accurate.

[bubby]

  The bows were OVER 60 inches.

Yeah and 62 ntn is a reasonable length for a 28-29" draw. Even with a rigid handle

[gfugal]

Do you guys run a humidifier in your house or HVAC unit? just curious what you measure humidity with? not all hygrometers are equal, some have very limited ranges where they are accurate.

no humidifier or HVAC unit. At least not that I'm aware of. I just have a cheap hygrometer from Amazon but I've seen it vary between 35-55%. So I don't have reason to think it's not working if it's in the middle of that range right?

[gfugal]

Well I take that back we do have a HVAC unit on the roof of our apartment. However, it doesn't control the heat in the winter so shouldn't be running with central air. I think it's a gas furnace that heats our apartment.

[willie]

I have seen inexpensive hygrometers that are less than useless. not saying that yours is, but in a dry climate and a heated house, thing get quite dry.



https://forecast.weather.gov/MapClick.php?lat=40.3067&lon=-111.6844&lg=english&&FcstType=digital

[DC]

Willie, how are you supposed to read that indoor/outdoor thing. 70% out and 6% in sounds a little dry.

[gfugal]

Willie, how are you supposed to read that indoor/outdoor thing. 70% out and 6% in sounds a little dry.

yes, that sounds very dry (according to your chart my house should be around 15% today). Why would my hygrometer change at all (like if I put it in the bathroom, it can get up to the high 50s percentage-wise, but it's in the low 40s or high 30s in other rooms) if it's completely off entirely.  It's frustrating that I bought it at all if it's worthless. 

[willie]

Don
in that example, 70%RH at 10 F is equal to  6% RH at "room temperature", although it does not say what that room temperature is.  It is a simplified table.

to actually convert between any two temps, you have to use the psychometric chart. At first glance it looks rather complicated, but the one below is somewhat simplified. and in Celsius.

for example, a nearby outside temp to 10F is  -10 C

Along the bottom horizontal of the chart, enter the chart at -10C  and trace upwards  to hit the sloping line 100% humidity
then trace to the right until you find  the vertical at 20C.  You should be close to the humidity line that is for10%

inspection of the chart overall, tells you that there is darn little moisture in the air at low temps.
I just keep my bows and arrows in the shed in the winter, but I live in dry country like Greg.
Coastal BC might be more like the heavy line the chart uses as an example.

[Springbuck]

Pearl:  "Every bow, every piece of wood, and MOST importantly every bowyer is different. What doesn't work today will work fine tomorrow, or for the next bowyer."  This is pretty darn true and full of wisdom to start with.  As with anything else, you are going to have shimmering victories and crushing, baffling defeats.  On every one of my top ten best bows, I swear, I am asking myse;lf how I got away with it, or at least feel like I stumbled over excellence while  doing what I usually do

 Greg: "I keep asking but is there a point where too thin limbs actually increases the likelihood of a bow breaking?"    I don't think so, not in theory, Greg, but VERY thin limbs can create some problems.  Baker mentions once in TBB that he thinks kids' bows are harder to tiller.  When the limbs are super thin, and especially when flat, the TINIEST differences in thickness or strain distribution CAN be amplified.  Like, if a limb is 3/4" thick, ten scrapes at one spot may not even register, but if it is 1/4" thick, suddenly that is a hinge. 

Willie: " I would suspect something had changed with the bows that broke. went out of tiller? got too dry?"  I would agree with Willie here.  Maybe some other factor than what he mentioned, but look for what's different.

Now, I really thought you HAD that maple bow!  I thought it was pretty impressive, honestly, but that brings up my next thought.  That bow was a REFLEXED, RECURVED, HEAT-TREATED, HEAT STRAIGHTENED (which was a wrestling match) STEAM-BENT bow made of, I wouldn't say INFERIOR, but certainly not PREMIUM wood.  I remember how much propeller twist that stave had, etc...   and I think, maybe if you had made a 67" flatbow with 2" limbs, flipped tips, and a short handle, it might be a shooting bow right now.  I personally wouldn't have tried what you tried with that piece of wood.  And, it wouldn't have been so thin if it hadn't been so reflexed/recurved.  It just all adds up to strain.

Anyway, that's my two cents.  That tiller on the maple should have been money, so I don't actually know.