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Everything posted by Mike_Danielson

  1. If you read the Nagyvary review of the B & G book, you find that it was never submitted to a peer review before being published. This is a serious problem with the B&G book. So, I do not take it very seriously. I am going to go with Occam's Razor when looking at the famous Strad varnish. What ever varnish was used adjacent to the maple wood is probably the same stuff used above the wood; why have two varnishes around the shop. We all know from personal experience that the spruce must be sealed with something. Occam's razor again--every shop had a glue pot. Glue was probably used on the spruce as well, but probably not as many coates (my surmise). The inconsistency between the Echard results and the Woodhouse results with regard to the mineral layer has never been explained. How about this for a wild idea--all the instruments Echard examined are copies by master forgers. Mike D I edited this to change White to Woodhouse--my error. This inconsistency between Echard and Woodhouse is a big deal
  2. https://www.thewoodworks.com.au/shop/consumable/shellac-hardener/hardener-to-formulate-hard-shellac-polish-detail This is a hardener for shellac. You can also put the instrument in the UV box--shellac will harden overnight. Mike D
  3. 1. Brad, might want to re-examine the drill bit size. I suspect it is closer to 1/8". 2. You should take a look at brad-point drills since they stay centered 3. Consider drilling all the way through with one bit and then sleeve down the inner portion using a brass tube which has an inside diameter corresponding to the tip. 4. It has already been mentioned, but a simple lathe will allow you to do all of this, and much more. Mike D
  4. I have made the Fulton varnish successfully several times. When first heating the oxidized resin, it will take off at about 150 C. This is dangerous. Be covered up and have long, leather gloves. You must pick up the pot and place the pot bottom into a container of cold water to cool the reaction. Then reheat it again--you may have to do this several times before the reaction settles down. If you let water go into the resin pot, the resin may explode due to expansion of the steam. Once through the dangerous stage, add the oil. Let the temperature raise to 250-300 C Keep checking for color by dipping in and a placing a drop on a cold surface. The rest will take care of itself. When it has cooled way down but still warm, add turpentine. You can also use Hargrave's method which is similar to the old recipe of Mrs Merrifield's book. This method uses rosin and oil together and heating it up (He wants you to melt the rosin first before adding the oil). I suggest a higher temperature like with the Fulton varnish in order the get the color dark enough. It is safer than Fulton's method. Oil ratio is typically 1 to 1.5 compared to the rosin. regards Mike D
  5. Two states that border California sell Everclerar 190--Arizona & Oregon. Mexico has a similar product. Stove fuel probably has a lot of water in the alcohol. I drive to Oregon for Everclear--30 miles south of me. The obvious way of curtailing bad behavior is to put more people in jail. Here in the United States using 2010 data, only 12% of the working age males have a felony conviction. regards Mike D
  6. Would this method have any value in killing an infestation of wood worm in an instrument? I think the worm larva fill the back entrance with wood dust (probably a type of worm-poop) and that might prevent the ethylene oxide getting to the larva, but maybe not. Mike D
  7. This stuff is covered in Frank Mayer's "The Artists Handbook..." This is a very basic source that should be on everyone's shelf if you are doing this type of work.
  8. The temperature and time for stress relief depends upon the material (and you can look this up). For gray cast iron (which I assume old Stanley planes are made of), the temperature would be 550-650 degree C for a couple of hours with a slow cool. You need to get the temperature high enough so that the material looses enough strength so that the internal stesses can deform the material; thus, resolving themselves, but not too high a temperature that compositional or phase changes can take place within the material. I remember when Volvo and Triumph Motors used to brag about aging the engine block castings for a year before making the final machine work. Now I know how stupid this is, but at the time it seemed to be careful engineering as defined by the advertising department. regards Mike D
  9. As a materials scientist, I can tell you that the correct way of stabilizing the plane casting is to stress relieve it, and not let it age because this takes years for the stress to go away. The fact that so many Stanley planes stay fairly flat even after 50 years says that Stanley Tool used some form of stress relief. I purchased a Record plane of 22" length a number of years ago. It started out flat and then warped a few thousands of an inch. I flattened it but it continued to warp. So, I stress relieved it--now is was a couple of mm away from being flat--all twisted. This clearly indicated that Record never stress relieved it before machining it into a plane. A way out of this dilemma is to use wood planes--everyone know they go out of wack, and it is short work to flatten them. regards Mike D
  10. Before you get too revved-up, change out the strings. Strings are not perfect in that they do not have uniform properties along the string length, particularly after they have been used. Even brand new strings are not uniform. regards Mike D
  11. This subject has come up before, and I learned some useful things when reviewing it. For instance, those low angle French bow planes work because the blade is ground at a high angle of 40-45 degrees----this must make the total angle at around 70 degrees. Traditional bow making planes are going to be hard to find, and expensive, but you can find DIY articles on making them. A way of making it easier to construct is to make the plane of wood and then use a brass wear plate on the bottom (epoxied into place). St James Bay used to make these french planes, but I can't find them any longer. Pasewitz recenty made a small production run. Bow makers must have a room-full of planes, and when one does not work, they reach for another and another until they find one that works. My scraper plane from Harbor Freight required a new O1 steel blade which I fabricated in order for it to work. When the wood bottom shows wear, I will install a brass wear plate. Mike D
  12. https://www.google.com/search?q=lynn+bowmaker.&oq=lynn&aqs=chrome.1.69i57j35i39l2j46l3j69i60l2.4873j0j7&client=ubuntu&sourceid=chrome&ie=UTF-8 Lynn Hannings, bowmaker, sells copies of the Condit planes. They are about $100 and are made of aluminum with a steel blade. I have the flat one--it works so-so. I have made my own from wood with a brass bottom plate. I am still not certain what the best angle of the blade should be or whether the edge should be turned. Any advice on this? I have small planes with angles going from 30 degrees to slightly over 90 degrees (measured from flat surface that the blade sits against relative to the bottom). The approximately 90 degree scraper is a cheap Harbor Freight plane which works better than the Condit plane. One of the planes I depend upon for the early stages is a low angle Stanley block plane because it removes a lot of wood without a lot pull-out.. Mike D
  13. Do what Davide and Giovanni suggest--glue (perhaps pin) a piece of brass to the bottom. Thickness of the brass will be determined by how close you want to make the throat (opening in front of the blade). The plane looks pretty good, but the picture is not adequate to determine the alloy or quality of the plane. It being magnetic means it could be steel or evern stainless. You can see that it machines pretty easy which says it is soft. You probably will have to replace the steel blade with something that will hold an edge, based on the other shortcomings of the plane. regards Mike D
  14. The Stroup test uses a 2 pound weight. Here are some Stroup numbers for three very good cello bows: John Clutterbuck: 189 Howard Green : 213 Pecatte: 241 (played by professional musician and professor) My experience is people are not accurate judges of stiffness or weight. Bows are made by sticking to a standard set of dimensions that the luthier has become comfortable with, and then the bow is adjusted from there. Wood is an extremely variable material, and that alone can explain the large variation in bow properties from each maker. You cannot second guess what is the ideal bow for a player--there will be continual surprises. regards Mike D
  15. Nathan, Kohlstein used to make a travel case for the cello. It was truly a suspension case because the instrument was held by the body. There were inflatable bladders used to secure the body, and the neck was floating (not attached to anything). The case was huge, but it made it very likely that the instrument would survive baggage handlers. i suspect it would be possible to make your own suspension case--it would start by not attaching the neck to anything,and thus avoiding the "neck snap." I wonder what basic case you could use for the modification? regards Mike D
  16. Howard Core Co, has case parts for GEWA and their own Core cases. Maybe you can find something. No parts for Babelock cases. The next place is online luggage repair parts. May have to adapt another type of hinge. Repair will probably require Pop rivets and a drill to remove the old fasteners.. regards Mike D
  17. https://knifeinformer.com/discovering-the-best-knife-steel/ The above website rates the steels. It is likely that there have been further improvements in steel chemistry since Veritas started supplying their alloy. I would look for an alloy that has good edge retention with ease of sharpening. So, if you want to experiment, there are knifemakers that will sell the raw materials in various thicknesses--thus, you do not need to interact with the specialty steel companies or the mill that rolls the material into the desired thickness. As far as a vacuum oven is concerned, knifemakers wrap the steel piece in stainless steel foil to protect it from oxygen--thus, you do not need a vacuum over. But you will need an electric oven with electronic control because these steels need special attention to heat treatment. regards Mike D
  18. AS far as I can see, PM-V11 is a proprietary steel number that Veritas came up with. They did not invent this steel---rather, they went to a specialty steel manufacturer of power metallurgy steel and purchased an already developed steel for this type of application. If Veritas published the composition, there would be nothing stopping you from finding the steel manufacturer and purchasing your own material. This steel is going to be complicated to heat treat---you will need an electric/programable oven if you want to do it for yourself. I think this is what Evan Smith should do rather than purchase the already hardened blades. If Evan does not know where the steel comes from, it is easy to send a sample to a laboratory that will analyze and give you a composition. Last time I did it, it did not cost very much. That way, Evan can work with annealed material which will make his work a lot easier. regards Mike D
  19. I think I need to know more about this. How much base (calcium hudroxide added?) do you add to the rosin? The thing that confuses me is that rosin is 100% abietic acid; so it is 100% an organic acid. The organic acid will react with a base such as calcium hydroxide or sodium hydroxide to make a soap., but I know you cannot react all the organic acid (rosin) and still make a varnish. The varnish recipe books talk about a 5% addition of base to the rosin--is that what you mean?. I have been studying the literature to find out what is the chemical reaction between linseed oil and rosin when heated, but I cannot find the answer. It may be the diels-alder reaction that allows them to chemically combine to make a varnish. Drying of the varnish is by free radicals that crosslink the varnish using the unsaturation--they are naturally present in the cooked varnish and also form by oxygen that penetrates the film plus the action of UV light. Metal oxides catalyze their formation such as are found in Japan Drier. The Mariana manuscript 399 as mentioned by Mrs Merrifield mentions the addition of a small amount of alum to the cooked varnish, and this would supply a small amount of potassium and aluminum to react with the rosin. The old varnish makers used a small addition of calcium hydroxide to make the varnish harder and more water resistant. regards Mike D regards Mike D
  20. It does look like the steel is laminated. I did not know that they did this. I purchased two Record planes from Woodcraft in the 1980s--a # 5 and #7. Both warped and were almost impossible to correct since the cast alloy was some silicon cast iron which was very hard. It is obvious, now, that the castings were not stress-relieved properly. The #7 went on ebay, but I still have the # 5 which continues to warp. The original irons were tungsten vanadium steel, and they were not hard enough. I replaced then with a Hock blade which is O1 steel, and that fixed the blade problem. The two Record planes were replaced by old Stanley/Bailey planes from ebay which were easy to correct and make ready. regards Mike D
  21. I think it has been established that it is not your varnish. I think the problem is with your varnishing technique. I use American Painter wash brushes from Michaels. They look to be taklon bristles which are a golden orange color and are fairly stiff. The thing you are not doing is "tipping off." Once the varnish has been brushed out to make an even coat, you go over the varnish with a gentle brush to remove the surface bubbles--this is the last step. Look up tipping off. For maximum transparency, do not add particulates to the varnish. Color pigments go directly on top of the sealed wood. On brush cleaning, I use two bottles of oil varnish solvent to dip the brush into. Bottle 1 followed by bottle 2. And then into a commercial brush cleaner that is mostly acetone. Then wash in water using liquid dishwater detergent. Do not use steel wool--it leaves little pieces of steel in the varnish, and if it ever is exposed to water, your will have another problem of rust. You need to find an environment that is dust free. Of course we add solvents to our varnish to reduce its viscosity so it will brush easily. Turpentine is a good solvent for these cooked oil varnishes. You can always put thin coats on. The big problem is if you ever get "fisheye." But you do not have that. regards Mike D
  22. To understand the fear that scientists and medical professionals have about the corona virus, you need to do some study. The book "The Great influenza" by John Barry is about the 1918 flu epidenic--it is a very interesting book. You will discover that the 1918 epidenic came in more than one wave--it returned 3 times or more. The estimate of 50-100 million dead is a very imprecise estimate--no one really knows how many died, and it could be higher. Many things today are similar to 1918--for instance, the governments all started out by lying about the severity, and this mislead people into a false sense of security. Governments were slow to respond. Scientists at the time recognized that the influenza was new, extremely deadly, and they were helpless except to separate people. Of course a war was on, camps for solder training were breeding grounds for the virus, and the government war effort was not going to be interfered with. This created the petri dish that really kicked up the virulence because when it first appeared, it was not very lethal. And so on. The book is worth a read. By the way, according to the author, the earliest case of the 1918 influenza was found in the state of Kansas, not Spain. The governor of Washington state shut the state down , today. We are going to be impoverished. best regards and good luck Mike D
  23. Nathan is correct--you want both sides to be defect-free. From a fracture mechanics standpoint, any defects can initiate a crack during the bending or in later years when the side is subjected to a blow. The engineering science gives a clear answer. regards Mike D
  24. Link to planes of Lynn Hannings: https://shop.lahbows.com/collections/tools-stuff/products/bow-scraper-planes
  25. Davide, your plane has a very appealing design. Simple and well executed. Is there a problem with the shavings catching in front of the blade? Thus, you have to stop and dig them out. I have this problem on some of my small, hand-made planes for bows. The only U.S. source I can find for planes for bows are those of Lynn Hannings--I think she must have these made for her business. The design allows the shavings to be easily removed--I think this is an important influence in the design of these high angle (scraper) planes. St James Bay does not seem to be making bow-making planes at this time. regards Mike D