Welcome to our forum. A Message To Our New and Prospective Members . Check out our Forum Rules. Lets keep this forum an enjoyable place to visit.








Members

Usual disclaimers, might want to get a cup of coffee or tea, since this may be a little long. But on the bright side, a good bit of it will be pics showing the steps.
I would class this mod as "crafter level", since it would not take any unusual skills or expensive materials.
One thing I have seen mention of when there are discussions or articles about high quality bows is that the archetiers (luthiers who specialize in just bows) go to great pains to make sure that the fit between the frog and the stick is absolutely perfect. I am not entirely sure all of the problems that can arise from one that is poorly fitted, but what comes to mind immediately is that the slide adjustment of the bow hair tension might not work as smooth as it should or in very bad cases, the frog might be mechanically loose enough to rattle a bit. There's probably other problems that an ill fitting frog could cause, and maybe someone will mention them.
I'd be willing to bet that the average inexpensive bow (whether CF or wood) probably doesn't have near as good a fit there as a well made one that was done by a professional archetier.
I was doing a small mod/fix on my flute when I came up with this mods for violin bows. Flutes have a metal cap that screws into the end of the metal tube of the head that closes the end and also is used for making an adjustment. On a really nice flute, those parts will be precision made and fit together perfect, so they are very stable and pretty much air-tight. On a student grade flute, they are just mass produced parts and often may be a little looser than on the nicer flutes. So a budget trick/fix is to cover the threads of the plug with "Pipe Thread Seal Tape", and then they will seal and hold without rattling, much like a better made flute.
Pipe Thread Seal Tape is a non-adhesive tape made from just a band of very thin white teflon. Really thin, the kind I have onhand measures at about .003 mm, which is three one thousandths of a mm. Theoretically it would take a stack of about 300 strips of it to be a whole 1 mm thick. So it is super thin and super light. It is also pretty cheap, I think I paid 2$ or 3$ (USD) for a 100 inch roll of it. What it is usually used for is when you need to put together something like a threaded joint in steel plumbing pipe. You wrap the threads of the pipe with a layer of the tape, and then screw it together and it will go together easier, and be nice and water-tight and etc.
So I decided to try it in the space between the frog's metal liner and the stick on my Fusion bow. I wasn't having any problems, but I'd always felt the adjustment for the bow hair tension didn't feel as nice and smooth as I would like, and it seemed a good mod/experiment to see how hard it would be to line it with teflon and see if it made it smoother.
What I used to this mod was the tape, scissors to cut a piece of it, an x-acto knife to trim any excess, and (so long as I was taking the frog off for the mod anyway) a little bit of grease for the threaded metal part of the adjustment screw. I used cork grease made for musical instruments, but that is just basically chapstick with no sugar or flavouring. Any chapstick without sugar in it would work as well, or a tiny bit of petroleum jelly (vaseline). You want to avoid using food grease (lard for example) or anything containing sugar, since it will oxidise eventually and get sticky. Very thin oils made for mechanical things, like 3in1 oil or WD-40 should also be avoided, since they evaporate over time and leave the metal surfaces bare and unprotected again. Bare metals, like steel or brass (such as the adjustment screw and the nut/collar it fits into will eventually get enough moisture from the air to corrode or will wear out faster with no lubrication.
So, first step is to disassemble the frog from the stick. That's very easy just take the adjustment screw you use for adjusting the bow hair tension all the way out. You should be able to slide the frog easily right out of the stick then. This is the same procedure you'd do if you ever do the Fiddlestix method for cleaning your bow hair.
So long as you have it apart, check it for dirt or other problems. Mine was fine, but if you live where there is a lot of dust, fine dust might have gotten in there.
Next, cut a piece of the teflon tape and lay it over the metal lined groove in the frog and the nut the adjustment screw fits over. Press down kinda hard on the nut to leave an outline in the tape for the next step.
Now take an x-acto knife or other small sharp blade, and trim around the nut, to make a hole for it through the tape.
Spread out the tape so it is as smooth as you can get it, pressing it down into the liner (that metal lined groove on the frog) so it will stay in place when you put everything back together.
The "hard" part of this mod is pretty much done now. LOL
Put a LITTLE grease on the threads of the adjustment screw. This isn't a car or something, it only takes a little and more than you need won't help anything. Just enough to fill some of the threads, not a blob of it.
Now you carefully re-assemble the frog and put the adjustment screw back in. Make sure your bow hairs didn't get twisted the wrong way while you were working on the frog, it would probably be pretty easy to have that happen.
There should be a little of the tape hanging outside, since it is a little bigger than we actually need. So take an x-acto, and carefully trim off any excess. Keep the blade edge against the metal liner of the frog, not the stick, since it would be easy to cut into the wood or CF of the stick while trimming off the excess unless you are careful.
And congrats! You are all done.
Conclusions: I did not actually expect this to make any noticeable difference at all. It is such a fine point of the construction of the bow and such a cheap/simple mod, and I didn't think the bow had any problems.
However.. the threads of the adjustment screw had been completely bare.dry, and there was a little metal dust in them. That happens with any screw type adjustment that doesn't get properly greased. The manufacturer probably doesn't bother because this is an inexpensive carbon type bow, and they probably expect it will be replaced before the wear could cause a problem. A bow that was hand-made by an archetier, the player/buyer would expect more years of reliable use from, so they would grease that joint.
So the adjustment definitely feels smoother and a bit more positive. Any guitar players might understand if I said it feels a bit more like a well maintained set of Grover Super Rotomatic tuning machines instead of a cheap set of machines like you find on a 50$ guitar. For non-guitarists, let's just say they both work, pretty much, but one feels considerably nicer when you are using it.
Another surprise was I was really not expecting any noticeable difference in the playing. But after the mod, I noticed that I can feel the vibrations through the stick when playing with my pinky finger better. That was one thing I hadn't liked about this bow, that the vibrations through the bow were less, so it felt just a little more "dead" than my wood bow does. That is very much a fine point, and something that some, but not all players would notice. But I was quite surprised to be able to feel any difference at all.
This is actually the second time I have done this mod on this bow. The first time, I sat for about an hour just repeatedly loosening and tightening the hair tension to see if the teflon would stay in place, rather than getting wrinkled or bunched up as the frog was put through it's normal range of adjustment.
When I took it apart to check, everything was fine. So I did the mod again so I could take photos for the write-up to share it here.
One more point: If someone has the misfortune to have a bow where the frog is very loose, like loose enough to rattle.. It might take more than one layer of the teflon tape to fill the space between the liner of the frog and the stick. But it would still probably work, and would be at least a reasonable fix until one could get a better bow.
"This young wine may have a lot of tannins now, but in 5 or 10 years it is going to be spectacular, despite the fact that right now it tastes like crude oil. You know this is how it is supposed to taste at this stage of development." ~ Itzhak Perlman

Sorry for interjecting. I wasn't going to comment on this or any other thread for that matter, but I couldn't resist.
Great idea Dan, but the loosness in the frog can be taken up by just turing the threaded eyelet in the frog. Try turning it in 1/2 turn first or until the frog tighten's up.
Also, candle wax or paraffin can be used to lubricate the thread's on the frog screw and is less messy.

Members

Thanks Ken!
I think you have a better idea for a frog that is actually loose, with tightening the eyelet than my thought of using layers of the teflon tape. It would be better to tighten the eyelet first, since that actually would address the mechanical problem directly. My brain was still thinking on teflon when I wrote that. The teflon is probably better used only as a single layer, rather than trying to make too much of a "band-aid fix" out of it.
Teflon is a "non-stick" surface, and while I haven't noted any tendency of any frog/bow I've owned to stick, it seemed like a good idea to try, and I've decided I like the result. My frog was not actually noticeably loose, though.
I have to admit I am not fond of using paraffin or candle wax as a metal lubricant, except in a pinch. I don't feel it does that great a job and doesn't stay on the metal as well as a small amount of an appropriate grease. But "different strokes for different folks", and I think that with projects/experiments like this, that alternative ideas are *good*. They give a reader who happens across the topic more possibilities to consider.
"This young wine may have a lot of tannins now, but in 5 or 10 years it is going to be spectacular, despite the fact that right now it tastes like crude oil. You know this is how it is supposed to taste at this stage of development." ~ Itzhak Perlman

I like DanielB's idea. the tape probably protects the part of the stick under the glide from being rubbed so much and while creating a better fit. I have a stick that the frog is loose (it moves when I use greater force, it glides from side to side) maybe I will try DanielB's idea. I tried fiddlestix's idea before, but I tightened the eyelet, the screw and the eyelet did not line up any more, so the screw could not be screwed it so I gave up.
The other thing with lubricant on the screw is you could use pencil lead like you would on bridge grove.
1 Guest(s)

