Quad lam - 4 laminations - Why not more?

[adb]

I don't think so. The amount of glue left in the glue joint would be negligible. With TB3, the bonding action takes place at the molecular level. A good glue line shouldn't be a line at all... it should just look like the two (or three) pieces of wood are touching each other.

[Thesquirrelslinger]

here is the reasoning I followed-
if you have a glue line, with a 2% likelyhoood of failure... and you add another to make a trilam... you double the possibility- 4%. If you add another- 6%... I don't think I have ever seen a properly prepared glue-line fail on here though...

[adb]

The surrounding wood will fail before a properly made glue line.

[bow101]

here is the reasoning I followed-
if you have a glue line, with a 2% likelyhoood of failure... and you add another to make a trilam... you double the possibility- 4%. If you add another- 6%... I don't think I have ever seen a properly prepared glue-line fail on here though...

I agree 100% ~~~~~  a properly prepared glue-line should never fail, but sometimes haste makes for mistakes that's what happended on my last build. I glued up a tri lam, totally sloppy glue job, sure as crap it broke in the most likely spot......A Big Glue Gap...!

[mikekeswick]

Lesson learnt. Never rush preparing laminations! Rehearse your glue-up without the glue if you aren't confident.
Squirrel - have you done any study on probabilities? Are you sure you end up with a 6% chance of gluelines failing.....

[Thesquirrelslinger]

mikekeswick- All I am trying to say is that the more glue-lines, the more chances for you to make a mistake.
i doubt its 6 percent for a quad lam bow....

And yes, i have done some in both geometry, alg 1, and we are starting with it in trig.

[adb]

mikekeswick- All I am trying to say is that the more glue-lines, the more chances for you to make a mistake.
i doubt its 6 percent for a quad lam bow....

And yes, i have done some in both geometry, alg 1, and we are starting with it in trig.

I couldn't disagree more. Unless your glue lines are very poor, there is absolutely no reason to think the bow is more likely to fail.

[Thesquirrelslinger]

Do something once.Chances are you will get it right.
do something 100 times. chances are you will screw one or 2 or maybe many more up.

this is my reasoning- even though a properly prepared glueline almost never fails.
Those of you who have made laminated bows- have you ever had a glueline fail? How many have you made?

Lets stop this bickering(come on, we are acting like high school girls) and just agree to disagree.

[adb]

As mentioned in a previous post, I've made bows in the hundreds... mostly laminated, and I have NOT had one glue line failure. I've broken bows on the tiller plenty, but not one has broken as a result of a glue line failure.

Sorry, I don't agree with you. Practical experience tells me otherwise. Disagreeing is not bickering... it's just an opinion that differs from yours. I do try and base my opinions on experience.

Do something once, it might be good... do something 100 times and it'll likely be better.

[Thesquirrelslinger]

As mentioned in a previous post, I've made bows in the hundreds... mostly laminated, and I have NOT had one glue line failure. I've broken bows on the tiller plenty, but not one has broken as a result of a glue line failure.

Sorry, I don't agree with you. Practical experience tells me otherwise. Disagreeing is not bickering... it's just an opinion that differs from yours. I do try and base my opinions on experience.

Do something once, it might be good... do something 100 times and it'll likely be better.

sounds good.
just every time I try to glue up more than 2 layers for anything i botch the glue-up.

[BowSlayer]

Quad lam - 4 laminations - Why not more?

here is a bow that was made by the guy who taught me a bit about bow making. not sure on the order but it has 5 Laminate tapered longbow made with Bamboo purple heart Pau Marello and Lemon wood.

[adb]

As mentioned in a previous post, I've made bows in the hundreds... mostly laminated, and I have NOT had one glue line failure. I've broken bows on the tiller plenty, but not one has broken as a result of a glue line failure.

Sorry, I don't agree with you. Practical experience tells me otherwise. Disagreeing is not bickering... it's just an opinion that differs from yours. I do try and base my opinions on experience.

Do something once, it might be good... do something 100 times and it'll likely be better.

sounds good.
just every time I try to glue up more than 2 layers for anything i botch the glue-up.

Why? How can I help?

[Thesquirrelslinger]

i dunno. i have managed to make a 2-layer(RO and 'boo or cane, really dunno which cause 'cane is a species of boo)...
it delammed cause I left it outside on the woodpile in the sun and rain(glued with tb1)...
I have tried to pull off a trilam. it didn't work. then i tried to do a 2 layer tip overlay on a bow for a friend. it also failed(in a rather spectacular manner)...
i think its just me. I shall stick to selfbows and not have a problem.

[adb]

If you can do a bi-laminate, you can do a tri-lam! The gluing process is no different. If you're using TB glues, your surfaces must be clean, flat and fit exactly. Eliminate 'gap filling' from your vocabulary! I use 2" wide lams, and stack them in whatever combo I'm wanting. Wrap with bicycle inner tubes, and you're good to go. The backing and core lams are usually 1/4" thick, and the belly is whatever thickness is needed to make weight.

Stop leaving laminated bows in direct sunlight!!  That's not the bow's fault, that's your fault!! If you treat your bows like firewood, that's exactly what they'll become. 

[Thesquirrelslinger]

yep- the overlay was kept in the basement.

The trilam was my 2nd bow.
and i treat my red oak longbow like firewood with no issues... it seems to like it