Frog & Tip widths

[Regis]

In learning to restore/rehair bows, I'm seeing a difference between ferrule and tip widths. This puzzels me because I don't know how to adjust the amount of hair to fit correctly. Should I be concerned about filling the width of the ferrule or tip plug? All the literature I've seen says about(?) 150-200 hairs. It seems easy to "overload" the tip. What really determines the amount of hair? There is only a little difference in ferrules but, a lot of difference in tip plugs. I have to believe any significant concentration of hair approaching the tip makes a difference to the player.

Help or clarification appreciated.

Regis

[fiddlecollector]

You usually have a flat ribon of hair not too thick and appropriate for the widthof the ferrule and nut, if you have to much hair fitted you can run into problems .Also if the hair is fitted with too much hair a previously quite stiff bow can become floppy and useless.

I don`t know how this helps but i think its more judgement with experience rather than counting the hairs.

I stress that i don`t do rehairs but i`m planning on learning it ,as its rather expensive in the u.k to get someone else to do them.

[Woodland]

There are commerically-made hair guages available from several distributors. They eliminate the guesswork (or hair counting) and can quickly help you determine the appropriate amount of hair needed for the bow depending on which type of bow it is (violin, viola, ect.). There's one manufactured by Herdim sold through Howard Core and Co. and International Violin Co.

[Andrew Victor]

In my experience - using bows, never rehairing them - it is really important to use the proper amount of hair for the stiffness of the stick. the width of ferrule and tip are not the factors.

Some technicians to use a standard amount for each genre of bow (violin, viola, cello), but my experience is that this is incorrect.

There is also something to be said for rehairing with a range of individual hair diameters since this will vary properties of the stretch hair that affect tone. SO the actual number of hairs best for a particular bow will depend on the gauge of the hairs - but I think theoptimum total weight of hair for a particular bow should be fairly constant.

There is lots more that I have not learned, but I don't know what that is.

Andy

[Craig Tucker]

"I don`t know how this helps but i think its more judgement with experience rather than counting the hairs."

Exactly.

Each bow is different. The right amount of hair, within reasonable parameters, is determined by the size of the mortices. Then again, the playing characteristics of the stick should really be the determining factor - because if the bow doesn't play well - what use is the hair?

The usual tendency of the customer is to ask for "extra hair" also. They think that you're gointg to skimp, or that you're getting rich by holding back three or four hairs from their bow, I guess.

More must be better.

But the bow itself will tell you how much hair to use and the only way to learn that is to just keep rehairing them. Too little isn't good either - Just right is what you want.

Like most things in this field it takes practice.

[Craig Tucker]

For what it's worth - this is exactly how I do it.

What I usually do is take the old knot out of the mortice (whichever mortice, they both have the same amount of hair) and look at the diameter of the hair going through the old knot. That gives me some idea of how much hair the bow started out with. Usually, in the older bows, it is a fairly accurate gauge of roughly how much hair you want to put in the rehair. Sometimes - not very often - they used too much or too little hair, and you need to adjust the amount you put in. It’s a judgment call.

I have learned by repetition to separate out a certain amount of hair from the pound, which I then twist into a tight cylinder in order to see how big the bundle for the rehair will be. It is really an arbitrary method, as they all are, but is as good as any other method. It doesn’t take long before you are able to tell fairly quickly whether the bundle you want to cut from your pound is slightly too big or slightly too small for that particular bow. Add more or less hair to suit your estimate, cut it off, put the first knot in one end and do the rehair. If you're like me you will put the first knot in the darker end and start at the tip - if not, do it however you do it. Either way, you will slightly mis-call how much hair to use fairly often when you first start, but usually it isn't so far off that the rehair needs to be redone. Usually the problem of too little hair will show up at the spread wedge, but if the spread wedge is tight enough, it will still spread the ribbon the complete width of the ferrul. If you make a mistake and you’re not happy with the results - simply start over. At the worst what is it, an extra hour's work and .50 worth of hair? It’s the only way to learn.

[administrator]

We have a couple hair gauges in our catalog, but you know, most rehairers use thumb and finger to get the right "feel" of the hair. Rehairing bows takes practice - a lot of practice! I've done maybe a couple dozen bows myself, and I don't have the feel yet. But again, it's not what I do, so maybe I won't ever have it. I've used the Herdim gauge and find it works ok. I also have one of those cool brass guages with the adjustable mouth and and tooth lever? Very cool. But I think I want to learn to do it by feel, rather than using a gauge.

[Renaissanceman]

I am only beginning to understand how many hairs that a bow needs when rehairing. I started by using slightly over 150 hairs per bow by counting them, allowing for some that were slack and had to be cut off initially. After about 40 rehairs, I now grab a hank that I figure is about the right size diameter for the bow being done, and this seems to work now. Also with more practice, the number of slack hairs is greatly reduced and now I have maybe 3 or 4 hairs per hank that for some reason are not as tight as the rest. For a person just learning, I'd recommend that you use a slightly less amount of hair than too much. You can get a nice ribbon with less hairs than with more hairs.

As CT Violin mentioned, looking at the old knot of hair will tell you pretty much how much hair that the bow you're working on will take. I always figure that the person who did the rehair before me was more experienced than me and knew what they were doing!! Also, the tip mortise size has a lot to do with how many hairs you can use....only so much will fit in there!!

Also, I started doing rehairs from the tip then doing the frog end. Now I prefer to start at the frog and get everything right there and then finish at the tip. I'm able to get the ferrule wedge much tighter this way.

[Regis]

I sure want to thank you all for the input. Not as 'cut-n-dry' measuring/counting as I thought. Inspecting the hair/knot that I remove has helped in another way. My tying thread, although strong enough, is much tooo thick and that's why I've had trouble even with the right amount of hair. Also, I sure want to learn/advance to take into account the stiffness of the bow. I never gave that a thought! I had been working with the same 4 bows (over and over) for practice and ran into problems when I went beyond those 'cuz' I thought I knew what I was doing.

Again, thanks,

Regis

[Stepan Demirdjian]

I agree with all of you that different bows require different amount of hairs.The gauges I use are of those described in Strobel's book.I have made two gauges for violin bows the one is 3 mm diameter for the softer sticks and the other 3,2 mm for the stiffer sticks.This works good for me nearly ten years since make bow repairs.

The practice will lead you to determine whether a particular stick is stiff ot soft.

[Froggie]

I have always thought that too much hair is a problem. I like to be able to tighten the bow, hold it hair side up, and place my thumb under the hair at the frog. In good light, I should be able to see the outline of my thumb through the hair. Too much hair dampens the sound. When you all say some bows need more hair than others, are you saying that the bow is too lively and needs the dampening action of more hair? Please clue me in on why some bows would need more hair than others. Maybe I have been laboring under false assumptions.

[Craig Tucker]

Too much hair IS one problem.

Some bows just require more or less hair than a single standard amount. For a number of reasons. Flexability of the stick is one factor.

On some bows, the mortices are larger than they are on others - for example on some tips the mortice goes practically from edge to edge - and on others there is a tiny little mortice, the tip itself may be narrower or wider, small and delicate or beefy.

And again, on the frog there are any number of different sized ferruls with varying widths, what may fill one bow perfectly will be scant on another.

If every bow were exactly the same, the same amount of hair would be correct for all bows, but that's just not the case.