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Josh Henry

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  1. Hi Brad. Check out this article posted a few years ago by Kari Azure from the Triangle Strings (Jerry Pasewicz's shop). This article highlights the main techniques. https://trianglestrings.com/cheval/ I use a Sherline mill, model 5400. Yes, I have an angle milling vise and I do have to get creative in holding the frog. Most often, I use cut wine corks to hold the frog in the vise. I do reinforce the fragile edges with tape to keep things from splintering. As mentioned in the article, I also will use thermal set dental cast when needed, but more recently, I prefer to use Thermo-loc to help hold oddly-shaped pieces (https://www.riogrande.com/product/grs-thermo-loc-fixturing-compound/118131). Feed and spindle speeds are generally not much of an issue because I'm only milling out wood, not metal. My mill is a manual mill, so feed speed is whatever I crank the handwheel, and spindle speed is usually what the machine sounds good when it is cutting. As far as the ball end mills, I have them in 5 or 6 sizes, as small as 1/8" up through 5/8." The size I use depends on the job that I need to do. The most common sizes that I use are 3/16" or 1/4" for single-sided chevals or 1/2" if I need to go deeper and get both sides and reestablish the entire underslide channel. For the repair in this thread, I would probably use one of the smaller mills--maybe the 3/16" if I could orient it as needed and remove the necessary wood. The idea is to remove just enough original material on the outside of the frog to give a perfect glue join, and also to replace enough wood next to the underslide (or inside the frog) to give durability and strength to the frog. I should also mention that I also have a Sherline lathe. A lathe is necessary in doing this technique to turn down the ebony piece into a matching diamater (as the ball end mill) to fit into the radiused void cut into the frog.
  2. Thanks for the additional pictures George. I would be willing to bet that once the gunk is scrubbed away, the heads of those screws will reveal that they are iron, not brass. I do find it interesting that the front screw has a slot that is not centered. This might not mean anything, or it might indicate that these screws were individually made by hand rather than mass produced.
  3. This is a common repair on older bows, and one that can have excellent, nearly undetected results that are very difficult to detect unless closely examined under a powerful light or a black light. I have a few comments... The fact that the button rings are pinned is no indication whatsoever of country of origin. Pin number and placement might hint of an individual maker, but not country or origin. Pins in buttons are pretty ubiquitous. Your mention of the silver underslide having been installed with brass screws would place the date of the frog well into the 20th century. Most examples of early German bows with screws have iron screws in them, not brass. I don't know when the earliest examples of brass screws were installed, but to me, that is a mid-20th century characteristic. Removing screws in underslides is often not too difficult if you use heat and the appropriate screwdriver. Most of the time, the only screws that I have to mill out are the rusted-in iron ones, but the vast majority of the underslide screws in frogs that I restore, I can back out and then re-install them after the work on the frog is complete. The pearl slide is cracked. You should just plan on replacing it, and using eyes that match. Speaking of the appropriate pearl... Look up examples of other bows by that maker as see what was originally used. When restoring historic bows, as much as possible, use what the maker originally used. Also make sure to fit the slide and install the eyes with the flame oriented correctly. Yes, you need to remove the underslide to do a good replacement on the missing ebony. You will not have good results if you try to fit in a piece that big without removing the underslide. The missing chunk of ebony goes deep enough into the frog that the lowest part is below the center facet of the underslide. In other words, if you just try to graft on a piece, you will have gaps. Furthermore, given the location (at the toe of the frog), every time the bow is tightened, the pressure of the hair tension will pull the frog forward onto the toe of the frog, putting pressure against the glue joint. This will eventually cause the new piece to fall out. Besides all that, removing the underslide will enable you to clean all the old glue and mess out from the channel of the underslide. The pictures above make it look like the underslide is already loose from the glue in the frog. At the same time, the back corner of the underslide can also be straightened while it is off of the frog. What needs to be done is to remove the underslide first. Resurface the break in the frog, removing all old glue and splinters. This can be done with a flat glue surface (planed, chiseled, or filed) or using a ball-end milling bit in a mill (creating a radiused gluing area). I prefer the use of the ball-end mill because it gives more gluing surface--and I can go a little deeper, angled into the center channel of the frog. The additional depth and gluing surface into the frog gives more wood that is replaced, rendering a stronger repair that will resist splitting out again in the same location. The idea is similar to what a soundpost patch does in an instrument--the patch reinforces a high stress area that would likely suffer failure again without the additional support. After the surface is prepared, fit in a matching piece of ebony--paying attention to the grain, the angle and the fleck in the new wood. Glue it in with your choice of perfect glue. Then use a chisel to re-establish the underslide channel. Reglue the underslide, re-install the screws, and then reshape the outside contour of the frog.
  4. I have the deepest sympathy for Mary and great respect for Craig. I didn't always agree with all of the things that Craig posted online and, on a few occasions, got into a little argument with him over some technique or belief or some other thing. However, his heart and quest for knowledge was unquenchable. He was a generous person and shared himself with everyone surrounding him. I got to know Craig personally over the course of about three years that we worked together in his latest interest of making bows. Although I never had the honor to meet him in person, we had weekly discussions over Skype in our working together. Craig became a pupil, a colleague, a close friend, a brother, a confidant. Our weekly (sometime more) Skype sessions often lasted well beyond the hour time slot that we planned but were always filled with smiles and laughter. Craig dedicated his time in the last few years to learning how to make a bow. He made incredible progress as a maker for someone that due to his illness had to spend much of his time at the dialysis center. Craig was gifted in using his hands, but also had the ability to smile and laugh at himself in his often less-than-successful attempts at stick and frog making. However, he kept on at it as long as he could, and it brought him great joy to learn. Here’s to you Craig. You brought a spark to the people around you. You shared yourself selflessly. You made us laugh. You made us think. You brought us joy. Thank you. Tonight, I will pull out the violin that you made and play it in your memory.
  5. I have always used nylon thread for my knots. I used to buy it from woodwind suppliers as oboe/bassoon reed-trying thread (size FF), but now I buy it on 1-pound spools from a textile thread supplier (Nylon, size 138 or FF depending on supplier). I used to use a dark blue thread, but changed about 8 years ago because someone went off to the northern woods to a week long rehair camp and came back as a "professional rehairer" and set up a local shop, and started using the same color. Now, I use dark green. For many years, I had a small bows of liquid rosin (rosin powder with a few drops of alcohol) on the side of my rehair bench that I used to secure my knots. However, about 10 years ago, I got tired of the sticky fingers and switched to applying Krazy Glue to the knots. I have never applied glue (or rosin) directly on/under the tied knot, but rather apply it to the end of the hair after I tie the knot, which wicks the glue into the tied hair and under the knot. I then flame the ends of the hair, sealing everything together. In the picture below, the knot on the right is the first knot tied, and goes into the frog. The knot on the left is the final knot, and goes into the head mortise. I do vary the lengths of my knots by a few wrappings to account for the differing lengths of the mortises.
  6. I've been using CA glue for years in my shop, and have dealt with this same thing. As my primary business is focused on bows, rather than violins, I go through lots of CA glue--so I usually purchase it in either 4oz or 8oz bottles. I keep the larger bottles in the refrigerator for the reasons mentioned above. My primary applicators to dispense the glue are simple, cheap chemistry lab pipettes that are easy to use. Years ago, I bought about 500 of them off of ebay for about $20. They are available in different sizes, easy to fill (and refill), and are disposable. Mine are similar to these, but have a straight, non-graduated nozzle. I can use a single pipette for months, cutting the nozzle shorter as needed. I primarily use the medium viscosity CA, but also keep pipettes of the thin and thick as well. I do not bother to try to plug the end of the nozzle, and have never had glue plug up the throat, and the glue still stays fresh. Only occasionally does the dried glue build up on the tip clogging it, but that is easily cut-off. Since using these pipettes, I've also greatly reduced the number of times that I've gotten excess glue all over the place from squeezing too hard (on a plugged tube) and having it shoot glue all over the place. This picture shows two new pipettes above the scale, and one that is partially filled with CA I have used daily for over three months. I use these same pipettes for the pin-point application of flux when soldering silver. I've used these to accurately mix proportions of liquid components for varnish and even the occasional mixed epoxy. Try it--you'll like it!
  7. I don’t have much opinion as to whether or not old spruce vs. new spruce is better tonally for a soundpost. However, for years, I have used some incredible spruce that came out of a piano that was made in the late 1800’s. The piano was a total wreck, and was being thrown away, and I ended up with it so I could salvage the ivory from the key tops. When I took the keys out of the action, I was amazed at the quality of the wood that the keys were made from. They were made from very straight grain spruce, mostly fine-medium grained, with a few of the key beds having wider grain. Also, the black keys were made from ebony. There was enough wood in the one piano to last much more than I will ever use. Over the years, I’ve used far more of the spruce than I ever have of the ivory. I’ve used the spruce to make soundposts, replace edges and corners, and even a few bas bars. I love using spruce this old for wood replacement on old violins because it has the right golden color to match the wood on older violins. The ebony keys are just the right size to make nuts and saddles. There are a lot of old pianos out there that get scrapped, and the wood in some of them is completely salvageable, and great for use in violin repairs.
  8. My last resort for this kind of thing is to just throw the frog away and replace it with another one. Bows like these tend to break at the head or have problems that exceed the value, so I keep every old frog that I can, so when I can't get a frog open through the various means mentioned above, I'll just mount a replacement frog to the stick. You may not have been rehairing bows long enough to have a drawer full of them, but keep at it, and some day, you'll have plenty of spares. BTW, I do tell the customer when I have to do this, and so far, nobody has ever cared that there is a non-original Chinese frog on their factory-made Chinese stick.
  9. I've got the Knew Concepts saw. Mine is an earlier titanium version (similar in design to the aluminum versions), made before the titanium "birdcage" design that is being made now. If I remember correctly, the titanium that was used was left over from the construction of F-14s, or something like that. Mine has the adjustable quick-release cam design that holds the blade, and I upgraded the handle to one made from rosewood. I can't comment on how it does with cutting f-holes, as I've never before done that. Overall, I really like the saw, and it works very well--I bought this for work with bows, but end up not using it much because I prefer the 3" depth on the saw throat for bow work. If you are considering purchasing one, send me a message, this one could be available.
  10. In bow making, I find that the most difficult part is the very last thing--but usually the first thing that players look at--stamping my name on the stick. For those of you that have only used a bridge stamp, stamping pernambuco is an entirely different thing (for one thing, you don't use a hammer). Sounds easy, but it is not: Get it straight. Get it in the right place. Get it centered. Get it to an even depth (top to bottom and right to left). Get it nice and black (takes candle soot, not just heat). Press hard and hold it there without moving or shaking (remember, it is really hot at this point). But don't press too hard or you might crack into the mortise. Don't burn myself on the hot stamp. Don't slip. Do all of this on a facet of the bow that is only 3.5mm wide. Any questions why you see so many old bows with crooked or faint stamps?
  11. I'll add another agreement to the many comments above that this is an early Nippon bow. It is definitely not English or French, or remotely valuable. The stick is of some strain of rosewood, and apparently, the frog was made from a similar material mounted in brass. There is nothing carefully made about any part of this bow, and cleaning up and restoring it won't help it's provenance, value, or playability. More photos won't change this either. I cannot fathom why anyone could come to a conclusion about this bow that compares it to Dodd, Tubbs, or Peccatte (which are three quite different and distinctive makers!).
  12. Just don't confuse the physical term 'elasticity' in the wood with 'stiffness' or 'flexibility' (as in what a player feels). They do not correlate.
  13. Brad, this is also what I do when I fit the silver pin. I do hammer it on a metal bench block to peen and expand it. I can usually do this without splitting the ebony backing, but it does sometimes happen. No, I don't re-pin then petit-talon when I glue it into the frog. It is a tight dovetail fit on the edges of the slide channel, and when gluing the ebony backing (of the silver) to the ebony in the frog, there is no reason for any additional pinning. As most modern bowmakers do, I use CA glue to glue almost everything when making a bow. The top side of the prepared slide, followed by the back side showing the silver pin.
  14. So here are a few pictures from this morning's Skype session with Craig. In these pictures, we are cutting the channel in the frog, in preparation of fitting the pearl slide. We started by measuring out and scribing lines on the edges of the frog that define where the slide channel will be cut. Next, the channel is cut, paying particular attention to the desired taper of the pearl, the depth of the channel, and making sure that it is centered in the frog. The slide channel is left square-shaped (without dovetail) at this point. After the slide channel is defined and cut (to the desired shape, width, taper, and depth), the dovetail where the pearl fits in is cut with an angled chisel. The cutting of the dovetail shape actually goes quite quickly. In the first picture here, Craig is deep in thought. In the second picture, he has just had a cup of coffee.
  15. What you've described here Brad is exactly the process that we will be doing. Briefly, here is the process: I glue both the pearl and silver to the ebony backing, and fit it all together to ensure a correct and uniform fit into the dovetail channel in the frog. Before gluing the pearl slide blank and silver butt plate to the ebony backing, I file the two pieces so that the fit between the pearl and silver is perfectly flat--as this becomes the finished butt joint in the frog. When gluing to the ebony, I make sure that no glue gets into that joint, creating any gap. Once glued, I place a silver pin through the silver and ebony to hold the silver in place when filing and fitting into the frog. Once the entire piece (of ebony, pearl, and silver) is fit into the dovetail channel in the frog, then I will file the front of the pearl to fit against the back of the ferrule. any extra length of the silver butt plate can be filed flush with the back of the frog, creating a perfect fit and length. Once everything is fit and filed to the correct length, then a single cut is made through the ebony backing, which leaves 1.5 to 2.0mm overhang of the silver over the ebony backing. This also leaves a small extension of the ebony backing under the end of the pearl that will extend under the silver when the slide is pushed in. At this point, the silver butt plate is ready to be glued in, but the heel plate needs to be fit first. Here is one of Craig's more interesting expressions, as he looks longingly at frog-in-process. The next step is fitting the wedge-shaped heel plate to the end of frog, and then gluing it in. Once glued in, then the butt-plate fit earlier will be glued in, forming a flush butt joint between the two pieces of silver. The final step is in filing flat the bottom surface of the frog that has the bottom plate of the ferrule, the pearl slide, and the butt plate.
  16. Only when I'm about to crest the top of a mountain on my bike!
  17. Nick, I've got several I will send to you. I'll package them up with the Dragonetti bass bow that I am sending you anyway. I'll give you a call soon.
  18. Yes, on bow frog slides that are simply stiff, and not glued in place, I will use a tri-folded piece of tape to remove the slide. I usually use a Scotch-type of tape, but the blue painter's tape works quite well too.
  19. I've been using this same frog vise for almost 20 years now. It is just two parallel pieces of wood, held with 4 aligning pins in the corners, and tightened with two bolts. (The frog pictured is a 1/2 size frog.) Without much tightening pressure at all, this vise can hold all sizes of violin, viola, and cello frogs very securely, and without damage to the underslide or top side of the frog. There is no difference in how this vise holds a hill-style frog or a Vuillaume-style frog, and because of this vise, I've never had a need for the little frog holders in different sizes and styles that are used (and taught as necessary) in the rehairing courses. I've got a larger one that I use for both French-style and German-style bass bows. I've used this vise to hold frogs very securely when I'm chiseling out the mortise, pressing in plugs for a rehair, or clamped to the table of my milling machine for more complex repairs. The cork that holds the frog is not fully 1/2 of a wine cork, but more like 1/3 the thickness. I replace the cork about once a year because it does get compressed over time.
  20. I do agree that most people probably don't need to do something 1000 times to "master" it, but you might be a bit optimistic here on the "2 or 3 times to master" and also the "almost intuitive" part in reference to rehairing bows. It usually takes me about 20 minutes to rehair a bow (not including the time for the hair to dry). Once the hair is dry, another 5 minutes to fit a spread wedge and start the rosin. And yes, all bows that I rehair are done in a professional manner. Six rehairs in a day is a slow day for me. I don't usually schedule rehairs on every work day in my shop, but prefer to schedule them all on two or three days during the week. It is not uncommon for me to do more than a dozen rehairs on a busier day. A heavy, torturous day is where that number climbs past 20 for the day. I think these numbers are probably similar for others that specialize in rehairing bows. 6 X $65 is $273 This takes into account how much I have to pay the 'guvment in taxes, the state for "unemployment," and the credit card company for the privilege to accept their credit card.
  21. Hi Nick. To remove a slide that is really stuck, I fight fire with fire. That is to say, I use super glue. Step 1: I put the frog in my frog vise, so it is secure and will not be damaged. I use a thin strip of wood (for me, it is the strip of maple that I use for frog plugs) that I will carefully glue to the top of the slide, being very careful that the glue does not overflow onto the ebony or metal parts. Step 2: Once the glue is dry, I'll use a small jeweler's hammer (occasionally, a BFH will be needed) to tap on the end of the stick. I'll hold my thumb on the glued stick over the frog, and can feel when it begins to move. Step 3: Once the slide can be removed, I pry off (or dissolve off) the glued stick, and then clean and polish the pearl slide. I'll also use a file on the edges and the back of the slide to clean away any of the old glue. At this point, I will be mentally prepared to dig and drill out the glued-in, endgrain plugs and correctly shape the mortises in preparation of fitting proper plugs to hold the hair.
  22. Jerry, of course you never want to use the force on the wedge, but I find that the best tool is a light saber.
  23. Don't ever reuse a wedge (meaning a spread wedge). You will never see a well-wedged ribbon of hair using an old wedge. Basswood is an excellent wood for the spread wedge as it is compressible and lessens the chance of damage to a fragile ferrule. On the other hand, for plugs that are properly fit into the head and frog mortises to hold the hair, maple is an excellent choice of materials. Properly fit plugs can be reused a number of times as long as the amount of hair used each time remains the same.
  24. I just responded to an old thread on metal bows by mistake. I meant to place this reply in this thread. There was a patent from the 1930's for a Lomonal bow made from aluminum. To my knowledge, it was the only aluminum bow made, and it is also the only octagonal metal bow made that I know of. According to the patent description, the metal was "aluminum or duralumimnn as the material for the staff." This is a rather cool bow, and plays pretty well. I have one of these Lomonal bows in my collection, as well as a Vuillaume metal bow, and a mint condition Heddon bow. All of these are examples are made from metal and are quite interesting as "innovative" ideas. As I have time in the next few days, I'll try to pull these bows out and photograph them.
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