LVL verses plywood

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Mad MAC

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The use of the plant quality control would be nice for a special run for aircraft woods. Limit the splices to aircraft requirements. Glulam style with 8-15 ft pieces. Thicker laminate of the LVL. Spars are the no compromise part. Finding wood long enough Is becoming an issue no matter the budget. Use the process but aviation grade.
I see one of the local (NZ) LVL plants special order maximum size is 18.4 m x 1.220 m x 90mm. One of these would probadly keep the world in aircraft spar of 10 years (or let one build a 2:1 scale minicab).
 

Yellowhammer

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Is the LVL plywood? Or is it a laminated beam like a 2x8 joist?
Does Home Depot sell it? Or is it available by order only?

Sorry for all the questions, if this is laminated lumber it might be worth a look.
LVL Would be way too heavy and not really nominal for aircraft usage. My family owns a Glue laminated beam, manufacturing company.
 

Mad MAC

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LVL Would be way too heavy and not really nominal for aircraft usage. My family owns a Glue laminated beam, manufacturing company.
Cool, you wouldn't know what the statistical spread is for the tensile properties for the finished products is typically.

When you as heavy do you mean they use heavy timber or that the amount of added glue has a measurable increase in the weight?
 

mcrae0104

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The wood itself is no more dense than sawn lumber. It's interesting to watch a log peeler do its work and turn a trunk into veneer in a matter of seconds.
 

BBerson

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LVL Would be way too heavy and not really nominal for aircraft usage. My family owns a Glue laminated beam, manufacturing company.
If you are saying laminated veneer is heavy, what sort of commercial engineered laminated lumber is suitable?
 

BBerson

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Plywood is more suitable for webs. The caps should be laminated from sawn lumber. The thin veneers are apparently heavy because of two much glue ratio. I would also be concerned that peeling damages the wood, but I don't know if that is the case against using plywood for caps. The caps should be made with the grain oriented lengthwise, not with half cross grain like plywood which is no good in tension or compression.
Are TGI floor joist caps peeled or sawn?
 

mcrae0104

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Are TGI floor joist caps peeled or sawn?
Lots of different products are available, some with sawn caps and some engineered (sim. to LVL for the caps). The engineered products let the manufacturer use the raw material more efficiently, and allows them to deliver products that perform really consistently without having to wait so long for a forest to mature before harvesting. There has been pretty massive innovation in that industry over the last 30 years.
 

BBerson

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I am thinking someone should sell an engineered laminated spar kit. It would be a kit of machined sticks 48" to 96" with scarfed ends. The builder would simply stack glue these sticks to make a spar of any length. The entire kit could be shipped by UPS for little cost. It would solve the dual problem of finding long aircraft grade lumber and the impossible cost of shipping 16 feet.
 

TFF

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Some Douglas Fir flooring looks good. Unluckily it’s not the Floor style on my side of the country to be stocked. Shipping a pallet in of unknown number of useable wood ends up more than just getting from AIrcraft Spruce.
 

alr

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LVL Would be way too heavy and not really nominal for aircraft usage. My family owns a Glue laminated beam, manufacturing company.
According to the wikipedia article on laminated veneer lumber it typically contains about 2.43% glue. Glue would have a specific gravity of about 1.4 which translates to 87 lb/ft3. If we assume that a sample of LVL is made of douglas fir (assuming 33 lv/ft3 for the doug fir) the calculated density of LVL made of 2.43% glue and 97.59% doug fir would be 34.3 lb/ft%. That is heavier than doug fir, but not by much (about 4% heavier), and the density of LVL would be much less variable than typical lumber of the same species because of the way the veneers that go into LVL are graded and selected.

The grading and selecting of the veneers could also make the product a little heavier than randomly selected lumber of the same species because the lower grade veneers are rejected in the manufacturing process, but of course that also biases the strength upward as well. Also, the veneers are pressed when a billet of LVL is glued up, and presumably that could add a little to the density, but probably by a negligible amount.
 

Aerowerx

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Consider....

You are talking about taking thin pieces of wood and laminating them together to "replicate" a solid piece. That is what is usually recommended for spar caps, isn't it? A properly laminated piece is more consistent than a solid piece of lumber.

And isn't that what plywood is? Yes, half the plys are at 90 degrees, but you can get MIL-P-6070 plywood with the layers at 45 degrees to each other. And, yes, you would have to compensate for that. It is more expensive but worth considering, IMHO.
 
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