Most of the time, speaking about tecnichal themes related to the bamboo rodmaking, a great focus and importance has been given to those new methods that have improved the performances of the rods in term of action, durability and aestethic prospective.
- How the hollow building impacted on the action and on the weight decrease?
- How the bamboo ferrules guaranteed a weight decrease and a better Energy transfer?
- How the different shapes of the rod are related to the rod action?
- How the introduction of new materials (glues and varnishes) have impacted on the durability, maintenance and beauty of the nowdays bamboo rods?
We could keep asking to ourself other questions like this, but in this article i would like to focus my attention on an argument too much often undervalued in term of impact for a bamboo rod. I’m referring to the finishing procedure of a rod.
Most of us know that the natural frequency of a rod has a great importance if we want understand deeply how this rod will behave in a dynamic point of view, in other words, how this rod will behave once we’ll be using it on the river.
Starting to say that the natural frequency of a blank is different from the natural frequency of that blank once we have finished it, let’start from this point for this article. Basicly what we do in finishing a rodi is just to add weight, but we also add this weight in a no uniform way all along the rod lenght. Think about reel seat and handle. In that case we add weight on the end of the butt; think about gluing metal ferrules or building bamboo ferrules. In that case we add weight to the end of the butt and to the beginning of the tip; think about guides and stripping guide; we add different quantity of weight along the rod. Think about varnishing…….oh my god!!! Yes varnishing we add weight all along the rod lenght but also this weight is not uniform in the rod lenght.
At the end of these operations we’ll find that the natural frequency of the rod has been drecreased and if we want, we can say also that doing this we decreased the reactivness of the rod. Well, in this last point we can go deeper, but i’ll do it in a next article. What i want to treat now is a specific argument of the ones touched before: i want talk about varnishing.
Too much times the varnishing action is directly associated to the aesthetic of the rod and only few times has been described how much a not good varnishing bring damnages on the performances of the rod.
Varnishing has basicly these main goals:
– protect the rod from humidity, UV rays and other athmosphere agents, but also protect the rod during its use, like it could be unespected falls or bits agains threes etcc.
– Improve the aesthetic aspect of the rod
– Impact as less as possible on the original rod action.
If we give a deep look to the previous goals we easily understand that there is a kind of trade-off to be managed. Of course the aesthetic aspect is always very personal and there could be people who like glossy style, people who like more natural aspect, others could love a fat belly on the guides thread, others could prefer a flat one. It’s also thrue that a much thickness of the varnish will protect the rod in a better way than a thinner coat, but i more thickness bring also a lot of weight on the rod and this is for sure not a good thing to do.
Let’s say we did a great job doing a 7’ #4 in two pieces blank, hollow building it, using truncated metal ferrules to get the lower weight as possible and our blank weight is around 58 gr, usually 45 gr for the butt and 13 gr for the tip (more or less). Do you know how much weight could add to this a wrong varnishing? At least 18-20 gr which is a lot of weight compared to the total weight of the rod.
Usually the varnish thickness is different between the butt and the tip but despite usually it’s less on the tip part the proportion of weight we add have a bigger impact on the tip and that’s the place where we’ll feel it easily once we start to cast our rod.
So what can we do to get the best results on the varnishing procedure?
We have to work on the following aspects:
- Choosing the right varnish
- Using the best procedure to apply the varnish on the rod
- Find the best way to mix varnish and thinner.
Oh well!! Now the real problems begin. Every rodmaker has its opinion on these procedures and i’d avoid to give the perfect varnishing receipt, also because one of the most beautiful aspect of the rodmaking is that it’s always a work in progress trying to improve things day by day, but at least we can make some considerations about it.
Which varnish should i choose? Pages and pages could be written on the different type of varnish and inside the same type the different solutions proposed by the chimical industry. What we have to achieve in our choice should be the followings features:
– good protection
– it doesnt get too much yellowed in the long term
– it must be hard but at the same time it doens’ have to impact on the flexibility of the rod
I found the Polyurethane type good for my purpose, others rodmakers use also epoxy or spar varnish. Some romantic one keep treat his rod using natural oils.
The procedures to apply varnish on the rod are several: brushing, spray, immersion, impregnation (too much heavy for my taste) and many others.
Regarding the quantity of mixing, they also depends on what kind of varnish are you using and what kind of thinner you’re going to use with it. Most of the rodmakers make a mix using 1/3 of thinner and 2/3 of vanrish.
So let’s try to get to a good conclusion assuming for the moment that a good vanrishing must have the right thickness ablt to protect the rod, to let it shine and to avoid to add too much weight on it.
In my personal view the thickness for the butt section should be between 0,002 and 0,003 inches and for the tip between 0,001 and 0,002 inches.
Here after are shown some pics that show the different thickness of the varnishing and you can also see how the varnish get yellowed after some time.
The one of the left is 0,008 thick and and the last on the right is 0,006 they both are too much thick. They add a lot of weight an as you can see they show a great yellowed tendency. The one in the middle is 0,003 and it has been taken from a tip section. It is also too thick for a tip section.
This is 0,003 inch and it could be considered a good result for the butt despite a little bit less it could be better
This is 0,002 inch and it could be considered a good result for the tip despite a little bit less it could be better
I’ll be back on this argument trying to go more deeply on some point. I can understand that this for experienced rodmakers is something of very well knewn but it could be usefull for people who are approaching rodmaking right now.