How to know...when to clean bow hair?
My Codabow Protege (store's custom version of the Prodigy) is 15 months old, and has been played 6 days a week since then. The hair still looks good... The sound, however, seems rough and hisses at times.
I only rosin twice a week and have taken to brushing the hair weekly with a toothbrush before applying a bit of rosin. It sounds great, for a time.
I'm assuming I need to clean the hair, but was wondering how to know when that is actually needed?
I've read Andrew's description of the alcohol pad and cotton rag approach which is attractive. I've a trial bow this week (JonPaul Corona) so it's not a bad time to do this if appropriate.
Most high-level professional simply have their bows rehaired on a regular schedule. One might be able to spend around an hour cleaning the hair, and get the hair to last longer that way, but at what cost and risk, if they can earn around $100 an hour from teaching?
What David said. I'd just get the bow rehaired. 15-month-old hair on a bow that is used as much as you report is hair that should have been replaced at least three months ago.
Oh my, hadn't considered that but it makes sense. It will be my backup bow, I find the feel and balance of my JonPaul Corona much better, but I want this bow to sound good as well. Rehairs doesn't cost my anything with the service agreement I have on my violin and that bow...
If rehairs don't cost anything extra, I'd get my bow rehaired twice a year!
When you feel that it's slippery and non responsive.
Rosin twice a week? Brushing with a toothbrush?...
Cotton - I only play one hour a day, and probably not near in the same way that you do :-) I was taught to be be conservative with rosin. About the time that Mary Ellen estimates my bow needed a rehair I read someone here post in another thread that brushing it with a toothbrush from time to time assured the hairs stayed separated. It actually really helped the sound, for an hour or so, but then the problem returned. Certainly an indication that I needed to have the rehair I am sure.
I wrote an article a while back explaining some things to look out for to determine if you need a rehair. It can be found here:
Bow hair under a microscope looks like barb wire. When we play these barbs are removed and that is why we get a slippery effect on old bow hair. Adding more rosin will not help. Get your bow re-haired once a year at a minimum. I have been re-hairing bows since 1975.
I use rosin very sparingly, maybe every other day or so.
Victor wrote, "Bow hair under a microscope looks like barb wire. When we play these barbs are removed and that is why we get a slippery effect on old bow hair."
I won't wait so long for a rehair next time...and will be using more rosin.
Search in the page for the word "wear" and read around that part.
Hair under magnification doesn't look like barbed wire, nor does it have scales. A rather simple question one might ask oneself is, assuming the hair has some mythical roughness, why, after a re-hair, doesn't the hair grip the strings at all until it's rosined? What are those supposed scales doing then? They're not doing anything because they're not actually there.
It's almost like a meditation to practice regularly and be aware of the variations of a practice session day-to-day. Was I feeling tired? Does my bow need a rehair? Maybe my strings are bad? Is the humidity different? And so on...
you changed the title question... I previously answered to "how to know when you need to change bow hair".
Actually the question, and title, was "clean", my reaction to comments and thinking about everything caused me to change my focus. Hopefully that was at least as clear as mud...
I use rosin sparingly. But I’m using Baker’s so I have to be fairly judicious as there’s a waiting list to purchase more.
"I’m using Baker’s so I have to be fairly judicious as there’s a waiting list to purchase more."
The rosin adhesion to the hair is more like a chemical bond. Over time that quality of that bond breaks down, with or without use. Hair does have tiny scales under magnification, I've seen it for myself. You can successfully clean your hair when it gets dirty which will prolong the function by removing dirty rosin and oils. Unfortunately, the process of cleaning tends to effect the evenness of tension across the band of hair. This is why it is advised for most professional musicians to just rehair the bow rather than clean it. They are good enough to tell the difference and need their tool running in tip top condition. Taking a bow apart repeatedly for rehair is not an issue to the bow, it is specifically designed to be successfully taken apart and put back together. In the hands of a qualified technician, there is no risk to getting your bow rehaired. The key word here is qualified. Here are some photos of things that were only caused by someone working on a bow: https://adbowsllc.com/2018/04/01/the-importance-of-finding-a-quality-bow-technician/
As with any violin topic, I read a lot of myth in this thread regarding how hair and rosin work together, however there is one thing to be aware of that has not been mentioned in favor of regular rehairs and that is that as a bow loses hair its behavior changes.
According to this article:
"Hair under magnification doesn't look like barbed wire, nor does it have scales."
Look at the magnification of the images. The pictures you're looking at are probably electron micrographs. The surface structures that you're seeing therein are exceedingly small. The conventional slip-stick physical mechanism for how the bow "grabs" the string does not depend on features at this scale. The area of contact with the string is enormous by comparison. The notion that the string somehow gets underneath these "scales" and cleaves them off really isn't reasonable. These surface features are likely a consequence of the molecular chemistry of the hair and the manner in which it grows from the hair follicle. Jean is still correct that it's "not inconceivable" that such structures could be damaged while bowing, but I've never seen any corroborating evidence of that. I've also heard that the reason horsehair seems to work so well is because of its excellent functional relationship with rosin -- it just seems to hold the right amount of rosin very well. I don't know whether the sub-microscopic scale features are responsible for that, or whether it's due to features closer to the molecular scale (maybe another factor of 100 or so compared to the features you're seeing in those images).
I would like to recommend the 1997 book "The Violin Explained" by the late Sir James Beament,FRS for these and so many other questions that come up here. I was lucky to purchase a hard copy when the book was first published (its retail price has since risen like the DOW). It is a non-technical book by a scientist/musician (also husband of a violin maker) that provides a wonderful introduction to almost everything you would want to know about string instruments and their accessories.
Lo and behold, my CodaBow Protegee was replaced with a new Prodigy. Apparently the agreement reached between the store and CodaBow requires bows from that special run for that bow to be returned to CodaBow for rehairs and other work. My store just replaced it with a standard Prodigy and my old one will be refurbished for someone else. Very interesting. The special Protegee just differs in looks and name, it's the same bow.