I had a little bit of trouble with applying layers of glue to the horn, there was always a void at the bottom of the groove caused by shrinkage of the glue, I rounded the grooves more, the humidity was about 80%, I think I no longer have this problem but I’m still not 100% sure of my horn-core connection. recently I glued the horns to 3 Turkish bows, now I’m applying layers to the Korean with smaller grooves and still a little bit of gluing v-splice connections
I glued six cores: 3 target Turkish, flight Turkish, almost Crimean Tatar (the shape and length are not entirely correct) and a Mughal which probably has a bamboo sal that is too short
Good process to find out what you get using multiple bows at a time.If you used 30 to 35 percent glue for joinery and the more the better after proper sizing it should hold together.
Hi, I think that 30-35% is definitely too much for horn wood joints, such a thick glue would gel too quickly, 20-25 is what I use and that’s about what everyone else does, maybe if you glue in a hot room like a sauna In addition, the final gluing should be done with a mixture of hide glue and swim bladder glue for slower gelling, then it might work with such thick glue
I find when making horn bows the time of year can make a difference.For me in the winter time in the room with the wood stove going.So yes the temperatures are in the 80’s F while joinery is done and while sinewing also using the 30 to 35 per cent ratio of glue.Using hide and sinew glue.
It works for me.
Same thing goes for tillering timing.I’d rather tiller a new horn bow in a moderate to higher humidity enviornment.
The glue needs a minimum of 55% humidity (when gluing a horn) when the humidity is too low the glue dries too quickly and the glue shrinks and a void may appear at the bottom of the groove
There is couple different things discussed here at the same time!
I use very thick glue - joinery, sinew, whatever. The thicker the better if you just get the sinew to absorb glue and not to gel before joining. 30% is definitely good in my use at 23 degrees celsius.
I also tiller in humid conditions, minimum 40%. But for a beginner i suggest 60%. This is because glue will become brittle in dry conditions. This will cause delaminations, make the bow really stiff and not take the bend properly in general. Also the bows are easier to adjust sideways when there is twist/bend.
Kuba mentions gluing horn in humid room 55%+, yes i do it too. Many things to remember!
Nice looking bow! Hopefully you will have good joints. Its good to make very differenr shape bows - this will teach you what profile works best. Remember to keep notes on the lengths, proportions (kasan, sal, tip)etc. This way you can fine tune for future.
I have different molds for bending wood that i do fine tuning of angles.
Just recently i noticed that the short kasan bows seem to work best. They are most stable and hold better reflex. Also i think the bow is faster if bending is happening more midlimb. This kind of bow that you have here needs to bend near grip more. Well, this is just fine tuning!
I agree.In my observations natural materials become stiffer in lower humidity.Making first bendings more stressful on materials.No matter what kind of wood or composite.
It’s a precaution.
It does’nt take long for humidity to infiltrate the top layer.Around a week or so if uncovered.
After the bow is tillered and settled in it is not much of a problem.
In fact the dryer humidity makes the bow more efficient then.A plus.
Interesting discussion. I use 25-30% glue for sinew and 30-35 for joinery. I’m pretty humid up here in great white north except in the winter months. I find the sturgeon glue gels up slower and is just as strong. Especially nice for horn glue up. Works quite well as a thin glue for sizing coats too.
I took pictures of the transition of the horn into the wood and one side looks nice and the other bad but maybe if the horn falls off I will be able to glue it better if the core is not damaged
Are you concerned about this glue up here or that it may be an indication of glue up further up the limb? I can’t see it being too critical in this spot.
I put the bowstring on bow after a week of drying and only one layer of 1.5 mm (don’t ruin it for your bows, I wanted to see how the horn connection works, I didn’t really care about Bow) I’ll put another layer on and start stringing, if the bow survives I’ll start mass production
