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Thomas Knight

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  1. I agree with you 100% Jacob. A few years ago I would have thought why not, but after hearing all the facts why machines should not be used I have concluded that the top luthiers out there are even more accurate than the machines and there is very, very little chance of catastrophic failure if done by hand. I had a cheap new scroll I wanted to cut on my fixture and when doing one pegbox wall it went fine, but the other side broke off a huge piece even with me being slow and careful, and it was a new in the white scroll. So once again, as usual, the student is wrong and the professor right. Who would have thought?
  2. Hi David, yes, they were both an engraving and a profile copy machine with ratios is 1:1.5 down to 1:10. I wanted to make a few custom bridges so I drew a bridge at a 1:4 ratio on carboard (4 times larger than the bridge I want to carve) and the reduction allows for extremely accurate freehand work. The ideal way is to 3D print the model you want in an oversize buck (the term used for the part to be duplicated) and because the GK models are 3D they can do complex copies down to radius, etc.
  3. Somehow I have the pics out of order as Pic 6 is the first, the rest are chronologically correct
  4. Hi Brad, I mounted a piece of pine on the fixture so I could do a quick description for the neck blank. Pine is softer than maple so the cuts wont be quite as nice. Pic 1--a side view of the clamps and fixture with a piece of 2 x 4 I had laying around cut to 2.5" x 1.25" x 12" Pic 2--top view with the blank bolted in place Pic 3--fixture with blank mounted in a vice Pic 4--sides cut 1" deep with the taper pic 5--.250 bit, .500" bit to be used on the router table to do the bottom of the tapered area Pic 6--old router table with radius bit Pic 7--roughed insert side view Pic 8--roughed insert top view Pic 9--closeup of cut This took 30 minutes total. I rushed this more than I usually do because it didn't matter but I think you see how it's done.
  5. Thank you for your work researching Anton Seitz for me. What an amazing, yet sad, history of the Seitz family.
  6. When I switched in '78 to the performance market I received an FAA certification for Aircraft Turbochargers. 'You cant park a plane on a cloud' was the phrase. Redundancy was the norm. I have some expensive violins in need of repair somewhere down the road. The last major repair was a sound post patch to the back of a JB Squire done by a Cremona trained luthier. $1400 in 2010. Top luthiers are worth their rates because of the incredible work they do. I admire the years of training and practice. Your guitars sound amazing. I have some 80's 'big hair' USA electrics in my collection. I have never seen a scroll with 2 grafts. They are probably 100-200+ years old. I am certain they looked much better than mine when first done.
  7. It is fine by me as long as the comments are constructive and most have been. I overtorqued a hyraulic accumulator bolt on a 75 RR Corniche and stripped the threads in the block. My old torque wrench was frozen inside. It became my lesson on helicoiling stripped out holes, with the British shop foreman saying 'We simply don't do things that way, my boy". "Check and recheck your torque numbers and plan to work this Saturday and Sunday as well as next weekend". British tough love, I say.
  8. Getting back to the main focus, this old and tired scroll I have has had both a short and a long graft done to it as well as lots of other work. Can anyone elaborate on why a short or long graft were used, and was it regional?
  9. Great, that is what I thought for the pronunciation. Thank you.
  10. Jacob, as usual you are right. I have thick skin so I welcome your scolding. I am not making excuses, but the water seemed to wash off the varnish where the cracks were and I am not sure why. I didn't use hot water, just room temp. It seems like the scroll was possibly revarnished in the past as it does not display the same numerous 'layers' the body has and is chipped and scratched everywhere. There is a serial number or ID scratched into the bottom of the pegbox so I figured the entire scroll may need to be revarnished. I am probably wrong. I used a rat tail rasp to rough cut the ducktail and went around the sides and then used emery cloth strips to eliminate the rasp marks. I went to 180 grit so far. I still have 220 and 320 to go. I scraped the top of the insert until I started to see the varnish on the top of the pegbox scrape off. It literally scrapes off with a fingernail. The neck too short, the entire scroll/pegbox angled and twisted. When I clamped the cracks I was concerned about being able to close them. The gap closed considerably, but I did not want to distort or crack the wall and make it worse. The expert here said the bushings in there were done with the cracks simply filled with glue, probably many decades ago and the wood distorted so much that he thought they closed as much as possible unless I extended the G crack by cutting into the wood so it could close. He didn't think that was a good idea. The front part by the E closed almost completely. The treble side D did close, but it also was an old repair where a bushing was inserted. The expert is out of town for a few days and he may insert a sliver in the openings. He said to wait before I do bushings so he can decide. I am not looking for accolades, I am asking for true opinions so eventually someday I will hear from the best out there 'well done'. How else can an amateur become an expert? Yes, we blunder, and we learn. I post these pics so I hear the truth, even if I don't like it. I honestly do take your remarks as a learning opportunity. Many years ago I was an automotive apprentice and eventually a certified R R master tech at a Rolls Royce dealership. I got a finger wagging every time they let me off the leash, but I embraced those lessons. My next graft will be cleaner, tighter, less varnish lost, etc.
  11. On the other ones I started with the pegbox first but it makes no difference as the cuts are parallel and the fixture holds either the neck or the blank. I have not built a fixture so a scroll already cut off the neck could be routed. That would require adjustable jaws The treble side was routed starting from what will be the thinnest end of the blank pulling toward the fat end, then pushing it back toward the thin part as the cleaning pass. The bass side was done the opposite way. Both cuts start by inserting the router with it off into the groove and then turning it on. I used a 1" long router bit (measured at the bearing which is even with the bottom surface of the fixture) I then turned the blank over to make the multiple plunge cuts which were parallel to the top of the neck so yes, parallel to the fingerboard. I never knew an angle was needed. Using a welding torch set with only the oxygen on the burning oxy creates a black ash. When used in annealing, you cover the surface to be annealed and add acetylene to a blue flame and heat the metal, alloys, copper, etc until the ash burns off the surface. It is now annealed. In fitting the actions the stock, usually cherry, is hand carved or routed to a close fit, maybe .5mm. The action is then covered in the soot or ash of the oxygen, but not heated. You push it into place and the ash rubs off where contact is made and transfers to the stock so you know where to remove next. The fitting on the most expensive shotguns includes side plates that contain the firing mechanisms and the work is three times as much as you have the main action and the two side plates. Those are called sidelock versions while most you see are boxlock which house the entire firing mechanism in a 'box'. It also explains why some shotguns were $35k in the 1960's and 70's.
  12. Hi Brad, Someone had mentioned that routing the pegbox was probably a bad idea so while I have done some rubbish violins that way I decided this was too nice of a violin to chance the pegbox being damaged, especially with the crack in it. I did that by hand. I prepared the new neck with the router only using the highest speed I could with an extremely slow cut pulling the router backward first. then pushing it as the bit is spinning clockwise and makes a clean pass. This is the technique used with a milling machine on aluminum as it grabs the bit and chips can get between the bit and the alloy. So it was a very clean cut as I pushed it in the direction of the spinning bit for a clean up pass and the .001" clearance allowed a nice finish. I then changed to a .625" end router and cut 1.00" in six .150" plunge cuts and two final .050" finish cuts to get the bottom of the insert square. So the entire insert was routed. I took it to my router table with a .750" radius profile shell bit to rough the neck round area. Then I scribed the outline onto the peg box walls and made a fixture out of two wood sections 1" wide by 1/2" thick tapered to fit the scroll into my vice. I used cork gasket between the wood and the scroll and went to work with my chisels. I have a sharpening system with 1k, 3k, and 10k wet paper on glass and a fixture to hold the chisels whiole sharpening. Years ago in my early teens my father was Bernadelli of North America and imported their shotguns so I was sent to Gardone for a few weeks to learn stock fitting onto actions using ash. So powder is a similar system to me. I reamed out the bushings and closed the cracks after soaking them with the system Jacob taught us. I was able to clamp enough pressure while also using clamps to hold the pegbox walls parallel by lining both sides of the pegbox wall with .250" x 2" x .625" on the outside and .450" on the inside so I had clamping surfaces at the top and bottom, and cork to protect it. I will do another lesser instrument step by step and document it. There seems to be shallow angle grafts and very long grafts and do not know which is best. That is a topic I would love someone to comment about.
  13. Thanks for your reply. My teacher viewed each step before I proceeded to the next. It is very important for me to get better and learn. This is graft #12 for me having practiced on rubbish. I took my time soaking the cracks starting Thurs morn and glued them on Friday about noon. I did the blank during that time and did the fitting and final gluing after midnight last night. After lunch today I rasped the neck profile and scraped it but the neck is not finished at all. It is in the 90's here most of the day and 80's at night. Glue dries fairly fast. Maybe I am rushing it a little because I am starting classes on varnishing in Aug and have a UV box to build, four violins in the white to set necks and scrape, and I am not doing any more to this one for at least two weeks. I do listen to instruction from you experts and your input is valued more than it may seem.
  14. Many thanks to all of you. Jacob, your wash system worked great. With the suggestions and help of many on MN; Jacob, Phillip, Mark, Brad, George, Jerry, Wood Butcher, Bill, I thank you for the guidance. I grafted a new neck block after securing the cracks. I am out of 11mm maple dowels for the bushings but here it is so far. I made a fixture a while ago to cut the neck blank at 12 degrees, but decided to follow the advice of experts and do the scroll/pegbox completely by hand. I traced the prepared neck blank onto the pegbox walls and took my time. I let it cure, and finished the roughing. The cracks held beautifully. The pictures show the fixture I machined on my old Bridgeport mill. A .625" x .250" bearing centers the .250" router bit and gives a perfect cut as the slots are .626". Two padded clamps hold the neck blank to the fixture which is held in a vice. I know this is unconventional, but it saved me time having the neck blank done in under 10 min. I also routed the neck round area on my router table with a .750" radius cutter before I glued it. 15-20 min in total prep for the neck blank. I would encourage any thoughts, comments, criticisms or input.
  15. Ok, the correct pronunciation of Markneukirchen. Is it 'mark-noi-keer-shin, mark-new-kur-chen, or mark-new-keer-shin ??? BTW, if I was born in Frankfurt does 'Ich Bin Ein Frankfurter' mean 'I am a hot dog'? I had to choose citizenship in '74, so 'Ich Bin Ein Americaner Frankfurter?
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