These are 3 1/2" red oak newels that were made in my south Louisiana shop (cold and fairly humid winter) and shipped to North Dakota. It's obvious that the M. Content in the 8/4 oak pieces has been reduced. This is not the first time this has happened particularly with oak.
It seems to me the oak should have split with a good glue joint (using Titebond 2 - both surfaces jointed with sharp knives) instead of pulling apart as it has done here. BTW my shop temperature was about 60F. No chalkiness was seen on the pieces after an over night set.
So my question is, why is the oak not splitting here instead of this failure on the glue line? The glued joint is not, in this case, stronger than the wood

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Why titebond 2? Wrong glue. titebond original would be much better. I like sawn surface better than jointed for glue joint.

The issue is that the two piece were not close enough to each other when glued. For example, when you ripped them, if the core was wet, it would dry and shrink enough to form a gap that you could not span and glue.

It is not the adhesive, but a gap.

Note that the best procedure is to rip and then plane and glue within 15 minutes or less in the winter when shops are very dry.

Need more?

So Doc
What you're describing is pretty much my practice. Everything I machine for gluing is glued immediately after.

I am 99.9% certain that the issue was your dry shop and the wood being a bit wetter than the shop's EMC. So, the wood surface dried and shrank a few 0.001" after planing and before you got the glue on and the pressure. It was so dry this winter in our shops due to the cold air outside being heated, which drops the humidity.

I had one very similar situation and when they glued within 5 minutes, they eliminated the problem. Note that even if you apply the pressure, if the air is really dry, the surface will shrink before the glue sets. TB II does cure quickly however.

Titebond II is an appropriate adhesive in my opinion. My experience with oak is that joints require more glue than non ring porous woods such as birch or maple. Oak seems to drink up glue. To ensure a good joint in oak I like to see a generous squeeze out along the entire joint. I spread my glue over the entire surface with a spatula and don't rely on the clamp pressure to squeeze the glue from a glue bottle bead. If you aren't spreading your glue it may be. part of the problem especially since the splitting seems to be mostly confined to the rope molded area.

Tom
i don't think that is the issue. i have a pizzi type glue applicator. Everything gets a generous and evenly spread glue film

Titebond II is an appropriate adhesive in my opinion. My experience with oak is that joints require more glue than non ring porous woods such as birch or maple. Oak seems to drink up glue. To ensure a good joint in oak I like to see a generous squeeze out along the entire joint. I spread my glue over the entire surface with a spatula and don't rely on the clamp pressure to squeeze the glue from a glue bottle bead. If you aren't spreading your glue it may be. part of the problem especially since the splitting seems to be mostly confined to the rope molded area.

Hmmm. My only other question is how long between glue up and turning? The reason I ask is the rope turning in particular opens up the wood to a large area of end grain. This will speed up moisture loss. If the machining was done before full cure then it is possible the wood could be tending to dry and stress the joint before reaching full glue strength.

Tom
I typically wait over night before machining.

There is indeed a lot of stress when a round dries. However, TB II gets much of its strength in the first 12 hours. By 24 hours, you are real close to 100%.

Note that the open cracks indicate drying. My opinion is that they dried slightly before gluing...the maximum gap when gluing is just 0.006", so it does not take much to get a weak joint.

If there was a gap, you would have likely noted the lack or small amount of squeeze out, as mentioned in a previous post.

Would a 3 piece lamination work better? Odd number of laminations for balance? It sure wouldn't look better for the rope turning though.

A three piece glue up adds to machine time and detracts from the appearance. I think it is a matter of starting with drier wood particularly when you are shipping to such a dry climate in the winter. When you think about it, the conditions are a perfect storm- material machined in moderate coastal climate, lots of open end grain, shipped unfinished to the driest location. I am not saying it can't be done but you will have the best chance of success by starting with wood bone dry.

Thanks to all for your comments. This has happened before as I said particularly with oak and in the winter. My other beef with oak (especially 8/4) has been honey comb splits but that is another topic. Thanks Doc and all

You mention the honeycomb in 8/4 Oak, and that is a drying problem. It stands to reason (maybe...) that a drying problem is at the root of the open joints also. I have heard that even diligent kiln management can still make for problem 8/4 Oak.

When I worked in a stair shop, we bought hundreds of Red Oak squares - 4x4 - from a vendor, and they were always glued for thickness and width from 4/4 stock. These still occasionally had or developed an open joint, but they were minimal. We had the squares turned by a turning mill, or turned them ourselves. The turning did not seem to make things worse (or better).

David
I dread whenever I get an order for oak. Probably 20% of the 8/4 shows signs of honey comb. I don't mind gluing up small turning blanks with 4/4 but most of my blanks are 5 1/2" to 7". I'm not sure that a piece with signs of honey combed, however, are less dry than other pieces without.

Others know better than I, but I believe the honeycomb is a defect of the drying process, in that it is rushed - "too hot, too fast' if I recall. It has to do with lower energy costs to dry the material.

Kiln drying, the schedules and potential problems are a part of the voodoo I have not gotten into, but I have dealt with some problems. Stands to reason (again -?) that if 8/4 is hard - and expensive - to dry correctly, that it may come out of the kiln on the wet side rather than over dry, and contribute/cause the problems you have.

You should not have more than 3% honeycomb in oak, so you comments about 20% indicate that the wood is not being dried correctly. If the 8/4 is air dried first, then the air drying yard is too fast of a drying situation (as David mentioned). Virtually 100% of honeycomb in oak is a surface check first; prevent the checks and you will prevent honeycomb. Checks originate at very high MCs (above 45% MC for white oak and above 50% MC for red oak) when the wood is dried too quickly (usually too low an RH and too much air flow).

You can hire an expert to examine your drying practices (like me) or you can attend an advanced class on oak drying and learn more about what is going on. The kiln, if you are going into the kiln under 40% MC, is not the cause of honeycomb, so do not worry about the kiln or schedule. Instead spend your time with what is going on at the high MCs.

of course, honeycomb does not cause glue line failures, but it does indicate that the drying process is not perfect, leading me to question if the final MC is also a bit off.

I buy from three different hardwood suppliers and a significant amount of the the 8/4 is HC. Of course they may be all buying from the same mill for all I know. I would prefer to use 4/4 and 6/4 but it is not practical for large face to face glue ups.
I've heard of microwave drying and thought maybe that was what is going on since microwave heats from the inside. But my info maybe false.

Probably 99.9% of 8/4 oak is dried by air drying first. So, if the weather for one month is very bad--low RH, warm, windy--then a lot of the oak put on the year at that time will be at risk of damage. So, it would not be unusual to see that several suppliers in a region would have the same issue. But, it is only those suppliers that consistently follow poor air drying practices that will have lots of honeycomb throughout the year. However, at the same time these folks are having trouble, there are many others that are careful and do not have any issues in any weather (or maybe just 2% of the pieces with some honeycomb). In short, 8/4 has a much higher risk of HC than 4/4, so the practices that work for 4/4 in an air yard need to be modified when drying 8/4. The best suggestion is to air dry 8/4 oak in a partially closed shed.

In your case, being in Louisiana, I would be concerned about southern oak, as we do know that southern oak has a much greater risk of checking and HC than northern or Appalachian. (If the rings are more than 1/4" wide, then we class it as southern oak, from a drying perspective.) In fact, in the South, we often see that mills will not cut thick oak in the three summer months, as even the best practices in air drying may not fully control checking and HC.

I only buy Appalachian. One of the suppliers I buy from Netterville in Mississippi has a large kiln and mill but they buy Appalachian. I don't know that they sell Southern oak except in 4/4 - probably for the same reasons you cite

A pretty good way to separate App. oak from So. oak is to look at the rings spacing. If 1/4" or wider rings, then So.