Percentage of moisture?

[Gainey Q's]

As an up and coming cue maker I have learned quite a bit from the folks here on AZ. Now I would like to reach out with a question of my own. I have bloodwood that is at 11% and I am wondering at what percentage is pushing the wood to cut? It is currently at 1.360 Dowel. The moisture meter that I have came from Harbor Freight and is an inexpensive one so I'm not sure of the accuracy of that meter. Thank you all in advance for your help. ~ Shawn.

 

[whammo57]

As an up and coming cue maker I have learned quite a bit from the folks here on AZ. Now I would like to reach out with a question of my own. I have bloodwood that is at 11% and I am wondering at what percentage is pushing the wood to cut? It is currently at 1.360 Dowel. The moisture meter that I have came from Harbor Freight and is an inexpensive one so I'm not sure of the accuracy of that meter. Thank you all in advance for your help. ~ Shawn.

Most of the pin type moisture meters are not that accurate. In my experience, denser woods usually read a higher moisture content than is really in the wood. Still, they are a good indicator and are useful.

I sometimes buy wood that has up to 20% moisture. I also weigh it and write the % of moisture and the weight on it. Then I dry it in my hot attic for several months. If you weigh it every few weeks, you can tell when it has lost its moisture when the weight stops dropping, regardless of what the moisture meter says. After that you need to let it acclimate in your shop for some time before you use it.

You don't need to let it sit for years as some people do but, a waiting time is really necessary.

Kim

 

[Dave38]

11% is still high, but that depends also on where you are in the country, the wood will only go down as far as the area you live in. Bloodwood, I believe, does take awhile longer than other woods to dry, so be patient. I weigh the pieces and mark the date and weight on them when I receive them. Then every month or so I check and remark them. Once they stop losing for a few months, I then start the turning process. I still do the same after turning, especially in the summer when the humidity climbs to 85% and higher.
I haven't work bloodwood yet, my stock is currently buried in the back of the racks, so I cannot say for sure, but I would take some off, seal it with shellac or the like, then weigh it and then do that for a few months and see.
Dave

 

[whammo57]

11% is still high, but that depends also on where you are in the country, the wood will only go down as far as the area you live in. Bloodwood, I believe, does take awhile longer than other woods to dry, so be patient. I weigh the pieces and mark the date and weight on them when I receive them. Then every month or so I check and remark them. Once they stop losing for a few months, I then start the turning process. I still do the same after turning, especially in the summer when the humidity climbs to 85% and higher.
I haven't work bloodwood yet, my stock is currently buried in the back of the racks, so I cannot say for sure, but I would take some off, seal it with shellac or the like, then weigh it and then do that for a few months and see.
Dave

I agree with everything you say Dave but .... I never have understood why people seal wood that they are trying to dry. I do leave the wax on the ends but I never seal wood that I am acclimating or drying. I have never lost one to splitting... I have had a few checks or small cracks.

Kim

 

[Paul Dayton]

Kim is right, leave the ends sealed and the sides open to dry. You're only trying to prevent the ends from drying too fast and cracking. You should also cut the bloodwood down to a size nearer what you are going to use. Otherwise you will spend a lot of time drying what will be sawdust while the inner wood waits for the outside to dry.

 

[whammo57]

Kim is right, leave the ends sealed and the sides open to dry. You're only trying to prevent the ends from drying too fast and cracking. You should also cut the bloodwood down to a size nearer what you are going to use. Otherwise you will spend a lot of time drying what will be sawdust while the inner wood waits for the outside to dry.

I have dried squares and 1 3/8 rounds and even bored rounds.... Some of the bored rounds have squirmed a little and I had to run the gun drill through them again. They do dry faster when they are round. I have been afraid to do that on some really figured wood for fear that it would move to where I can't correct it. It never really has happened. I usually dry squares and they take considerably longer.

If I buy squares that need drying, I run the sides on the belt sander to clean off the wax but I leave the wax on the ends.......... it seems to work.... I don't buy actually green wood. I think that might split.



Kim

 

[Dave38]

I wipe a coat of shellac after cutting hard stuff like bloodwood, ebony, and the like, for 2 reasons, 1) I have had ebony crack after cutting with the ends still waxed. Up here in Ma, the summers get hot and humid and the winters get cold and dry. Better safe than sorry. 2) My Dad gave me a gallon of shellac and I have no other use for it but this.
Softer woods I don't reseal.
Everyone does things a little differently, as long as the end results are acceptable.
Kim, one idea for the warping after coring is to use a 1/2" or so gundrill to dry it, then re-bore it to larger, final size after drying. It may offset any warping etc.
Dave

 

[Gainey Q's]

Cutting closer to size...

Thanks guys.. Paul, I was thinking of doing that, (Cutting the Bloodwood closer to size) but was hoping someone would suggest that on here as you did. Like I have said before, always grateful to the folks here on AZ. :thumbup:

 

[cueman]

I am far from a wood expert. But I think 11% on Bloodwood is pretty much ready to go if it is 11% all the way through. I would not be afraid to continue turning it some at that moisture percentage. Most of your colored exotic woods do not dry down to 6% like Maple does.

 

[Blue Hog ridr]

Dave, that's a great tip.

Now I have to buy another gun drill. Thanks Buddy. Yer more expensive than the wife is.
Haha.

 

[Dave38]

I am far from a wood expert. But I think 11% on Bloodwood is pretty much ready to go if it is 11% all the way through. I would not be afraid to continue turning it some at that moisture percentage. Most of your colored exotic woods do not dry down to 6% like Maple does.

I agree, the hardwood exotics don't follow the norm.I have found that to cut the wood on a bandsaw, to take the corners off or to cut squares from a board, look ahead of the blade slightly for a band of moisture/steam just in front of the blade, the heat from the cutting blade will show how much moisture is there........not even the best moisture meter, nor any other method will tell the owner, how much moisture is left as accuratly as this besides weighing it on a regular schedule and waiting for it to stabilize for a lengthy period.
JMHO.....
Dave

 

[Dave38]

Dave, that's a great tip.

Now I have to buy another gun drill. Thanks Buddy. Yer more expensive than the wife is.
Haha.

Sorry Terry, If I own multiple gundrills,....so shouldn't you....
When you coming to springfield,....? I got a meatball grinder and a CNC for ya'll to work on...:grin:

 

[whammo57]

I am far from a wood expert. But I think 11% on Bloodwood is pretty much ready to go if it is 11% all the way through. I would not be afraid to continue turning it some at that moisture percentage. Most of your colored exotic woods do not dry down to 6% like Maple does.

I found that a heavy piece of marble wood would never come down lower than 11%. I weighed it and it never got lighter and I dried it in the hot attic for months.

I think it is the minerals or something else in the wood that gives the pin type moisture meters an error in some dense woods.

Kim

 

[whammo57]

I wipe a coat of shellac after cutting hard stuff like bloodwood, ebony, and the like, for 2 reasons, 1) I have had ebony crack after cutting with the ends still waxed. Up here in Ma, the summers get hot and humid and the winters get cold and dry. Better safe than sorry. 2) My Dad gave me a gallon of shellac and I have no other use for it but this.
Softer woods I don't reseal.
Everyone does things a little differently, as long as the end results are acceptable.
Kim, one idea for the warping after coring is to use a 1/2" or so gundrill to dry it, then re-bore it to larger, final size after drying. It may offset any warping etc.
Dave

I know that ebony cracks easily and I do leave it sealed until I am ready to use it.

I like the small hole for drying and the big hole later...... I will try that........ thanks

Kim

 

[Sloppy Pockets]

I'm not an expert in exotic woods at all, but I do take moisture content extremely seriously, so I found this thread intriguing. I just went down to the stacks with my MM to get readings on everything I could reach. Before I began the readings, I did what I always do.

1. Check two standard references - my 35+ year old Bally block workbench, and my open palm. These let me know my meter is working correctly.

2. Check the RH of the workshop with my trusty old Taylor sling psychrometer.

My bench hovers around 6-8%MC all year round, my palm averages between 32 and 38%... depending on how nervous I am, lol. Today it was a very calm 32%.

The shop temperature (dry bulb) was 66ºF, the wet bulb was 53º, giving 13º wet bulb depression. That is equivalent to 40% relative humidity. At 66º and RH of 40%, EMC of the wood in the shop should be 7.7%MC. My MM only reads down to 6%, below that MC it reads 0.0.

Results:


Species . . . . . . Age . . . . MC

- canarywood ........ 10 ..... <6
- curly hickory ......... 5 ..... 7
- Tonkin cane ........ 20 ..... 8
- braz. rosewood ... 50+ ..... 7
- purpleheart ......... 10 ..... <6
- pernambuco ........ 25+..... <6
- brazilwood .......... 25+ ..... <6
- cocobolo ............. 10 ..... <6
- chakte viga .......... 10 ..... 7
- goncalo alves ....... 10 ..... <6
- cherry burl ............ 10 ..... <6
- bird's-eye maple ... 20 ..... 6
- curly maple ......... 10-50+ ..... 6
- spalted maple ....... 10 ..... 12
- shaft dowels .......... ? ..... 6
- B&W ebony .......... 10 ..... 10
- mountain mahogany 25+ ..... <6
- Gaboon ebony ...... 10-100+ ..... 7
- osage orange ........ 25+ ..... <6
- tulipwood .............. 10 ..... <6

Reference readings:

- maple workbench .... 35 ..... 7
- my own open palm .. 61 ..... 32

As you can see, I have almost no exotic hardwoods that are less than 10 years old. Some of the ebony and rosewood reading were taken on old instrument spare parts, many of which could be well over 100 years old.

Most everything in the shop was between 6-7% MC. The only real outliers in the data were B&W ebony and, surprisingly, spalted maple. Counterintuitively, the spongiest (therefore least dense) parts of the spalted pieces were the ones that read 12%. The unspalted parts of these splits read arournd 8% on the average.

I don't know the actual age of the maple shaft dowels because they are a recent purchase (6 months), but I'm sure they were kiln-dried because they came from someone I trust.

As far as density affecting final moisture content, the densest woods I have in the shop right now are lignum vitae and desert ironwood, but I couldn't get my hands on them. The next densest are pernambuco and mountain mahogany, (sg of both is around 1.2). That wood all read <6% MC on the meter.

 

[cueman]

I found that a heavy piece of marble wood would never come down lower than 11%. I weighed it and it never got lighter and I dried it in the hot attic for months.

I think it is the minerals or something else in the wood that gives the pin type moisture meters an error in some dense woods.

Kim

I am told it is the oils in the exotic woods that cause them to read higher on the moisture meter.

 

[cueman]

I'm not an expert in exotic woods at all, but I do take moisture content extremely seriously, so I found this thread intriguing. I just went down to the stacks with my MM to get readings on everything I could reach. Before I began the readings, I did what I always do.

1. Check two standard references - my 35+ year old Bally block workbench, and my open palm. These let me know my meter is working correctly.

2. Check the RH of the workshop with my trusty old Taylor sling psychrometer.

My bench hovers around 6-8%MC all year round, my palm averages between 32 and 38%... depending on how nervous I am, lol. Today it was a very calm 32%.

The shop temperature (dry bulb) was 66ºF, the wet bulb was 53º, giving 13º wet bulb depression. That is equivalent to 40% relative humidity. At 66º and RH of 40%, EMC of the wood in the shop should be 7.7%MC. My MM only reads down to 6%, below that MC it reads 0.0.

Results:


Species . . . . . . Age . . . . MC

- canarywood ........ 10 ..... <6
- curly hickory ......... 5 ..... 7
- Tonkin cane ........ 20 ..... 8
- braz. rosewood ... 50+ ..... 7
- purpleheart ......... 10 ..... <6
- pernambuco ........ 25+..... <6
- brazilwood .......... 25+ ..... <6
- cocobolo ............. 10 ..... <6
- chakte viga .......... 10 ..... 7
- goncalo alves ....... 10 ..... <6
- cherry burl ............ 10 ..... <6
- bird's-eye maple ... 20 ..... 6
- curly maple ......... 10-50+ ..... 6
- spalted maple ....... 10 ..... 12
- shaft dowels .......... ? ..... 6
- B&W ebony .......... 10 ..... 10
- mountain mahogany 25+ ..... <6
- Gaboon ebony ...... 10-100+ ..... 7
- osage orange ........ 25+ ..... <6
- tulipwood .............. 10 ..... <6

Reference readings:

- maple workbench .... 35 ..... 7
- my own open palm .. 61 ..... 32

As you can see, I have almost no exotic hardwoods that are less than 10 years old. Some of the ebony and rosewood reading were taken on old instrument spare parts, many of which could be well over 100 years old.

Most everything in the shop was between 6-7% MC. The only real outliers in the data were B&W ebony and, surprisingly, spalted maple. Counterintuitively, the spongiest (therefore least dense) parts of the spalted pieces were the ones that read 12%. The unspalted parts of these splits read arournd 8% on the average.

I don't know the actual age of the maple shaft dowels because they are a recent purchase (6 months), but I'm sure they were kiln-dried because they came from someone I trust.

As far as density affecting final moisture content, the densest woods I have in the shop right now are lignum vitae and desert ironwood, but I couldn't get my hands on them. The next densest are pernambuco and mountain mahogany, (sg of both is around 1.2). That wood all read <6% MC on the meter.

How deep are the pins on your moisture meter penetrating the wood?

 

[Sloppy Pockets]

How deep are the pins on your moisture meter penetrating the wood?

Good question. Most of this stuff is damn hard! Deep as I can push them, then wait to make sure the meter reading doesn't change on me. I'd be willing to drill a few tiny holes in some of them if anyone wants more accurate data.

I'm going to try and make some cuts on the longer pieces to get readings inside. Bear in mind, though, these things have been sitting in a fairly controlled environment since some young cue makers have been in diapers. A few of the ebony readings I got came from an old cello fingerboard that is well over 100 years old. I'm confident it's as dry inside as it will ever get.

The electronic resistance moisture meters are pretty accurate at lower moisture contents, but readings on different species are all over the map as the wood nears the fiber saturation point. The meters are almost universally calibrated for Doug fir at 24% MC, so you need a species correction table to get the real reading.

The better meters like Delmhorst have firmware that allows you to make the adjustment automatically with the meter, but they are way overkill for the average woodworker now that the inexpensive meters are out there. They work fine, but lack the better replaceable points. Still, all any of these are is a resistance meter with readout in MC rather than ohms. My little HF meter gets identical readings as my friend's badass Delmhorst J2000 for 1/10th the price.

Here's a link to a PDF of a Tramex owner's manual. It had the best species correction chart I am aware of, with lots of exotics on the list.


http://www.tramexltd.com/User_Uploads/Manual_PTM.pdf


So, based on this table, the OP's meter reading of bloodwood at 11% moisture content must be interpreted as actually having 13% MC.


Notice that the Tramex table only goes up to 24% MC, as does the Delmhorst table. That's because this type meter is not really accurate on wood that is higher in MC than that, no matter how high the meter reads to. Therefore, a reading of 28% MC is merely indicative of a higher MC than 24%, not an actual measure of water content by weight as might be measured by an oven-dry or other dehydration test in a lab. BTW I got this info right from the horse's mouth at the Delmhorst engineering dept.:wink:


Here's a couple useful online calculators:


http://www.woodworkerssource.com/movement.php

http://www.csgnetwork.com/emctablecalc.html


A last thing I find interesting is this map showing the average indoor EMC across the U.S. Seems that no matter how hot or muggy different places may seem, the EMC of wood stored indoors is 8% MC all over most of the country.

Since cues are primarily used and stored indoors (or in your car if you're an idiot, lol), it seems to me that the closer you can get the wood to 8% MC, the better the chances you'd have of it remaining stable for the majority of purchasers... at least in theory. That would mean both storing and making in an environment that is 40-45% RH.

FWIW I'm sure most experienced cue makers already know all this stuff, but I thought I'd give a little of what I've learned over the years to those who are still learning about wood.