Patrick Hastings

Some more information on the "pitch" might help. what kind is it? Receding from the piece sound very strange, is it like shrinkage or is it just slumping away like melting icecream? The matsuyani I use can catch on fire it does not really hurt it so I use a large torch head or if I am out I use a heat gun. The pieces I generally remove cold by sending a punch into the pitch near the item. The shock wave dislodges the piece most of the time with very little pitch attached. otherwise on more delicate items the pitch is gently heated until the piece can be plucked from the pitch and then it is washed in solvent to remove the residue. Matsuyani always work best when the entire bowl is at comfortable room temp or warmer. Warming up the pitch all the way through is a must for doing work that requires a softer pitch and it also give the best long term hold for something like a tsuba. Think of it as annealing the pitch. It removes stresses and allows everything to come to an equilibrium as it slow cools. If you just heat the spot where you want to attach the object you have areas that are not expanding or contracting as much as the heated area. Patrick

Silicon source for Silicon bronze is the "prealloy" FerroSilicon. Just throwing pure silicon source into the melt won't work so I am told. The Iron lowers the melt point of the silicon making it compatible with the copper melt. The iron is not a desirable element in the bronze, but you will see it in the compositions, its always there in tiny amount as a result of the FerroSilicon. I don't have a source for the FerroSilicon, but I know it is generally not a home made product. hope that helps, Patrick

Almost ready to come out of my post class coma... I think your on the right Path, Kevin. I suspect that you may gain much insight in short time watching over a live shoulder. Patrick

Thanks guys! Ric I think I might have something for you. Here is a shot of the size range mounted up ... Patrick

This batch is going to my Japanese metal working class, but you will be able to order from the next batch in a couple weeks if your interested in getting some. I need to weigh them and get updated photos on my website. Patrick

My new line up of Tiny hammers. .5", .625", .750, 875" diameters. 1144 strain hardened steel, double tapered holes. Patrick

Ah, I thought it might be that, but did not have the time to dig it out. Patrick

what happened to this thread? I Had two responses on here yesterday. Patrick

You know mine could have been over fireing It was quite awhile ago. But the numbers came from paper so I still think 1500F is a good temp. My cycles were about 10 hours and the bond was great. I love those big chunks, keep updating the thread. Patrick

Hey there Justin, That is a great looking billet. When I was exploring Brass and copper Mokume My research on the Phase diagrams led me to a temperature of 1500F being a little safer. The danger is The formation of Eutectic between any of the metals present which is the lowest melting point possible between two or more metals. The Zinc soaking into the copper is really the formation of Eutectic alloy which given enough time and temp will convert the entire billet to a puddle even though the temperature may have never exceeded the melting point of the original alloy and copper. 1500F is a much safer temp for that combination and should prevent Eutectic cancer from propagating throughout your billet or fuzzing your bonds. Looks like you lucked out though I suspect you did not run as hot as you think. If it were me doing it at that temp I would have ended up with a bag full of liquid. Clamping it while it cools is a good idea. Those to metals bond easily and strongly. Regards, Patrick

You need to use Lubrication be it burs, Abrasives, or Files. Specialty files for aluminum have a tooth pitch up to 1/8 of a inch to eliminated loading or at least make the file easily cleanable, Mcmaster sells them. I used to make Jian out of 6061 bar stock. I settled on 24 grit Zirconium belts and slower belt speeds with lubrication. WD40 worked well enough, but there are all sorts of commercial lubricants for belts and tools. Patrick

Ok, A 4" wheel happens to make that one simple! It has roughly 1ft of surface So Your final RPM is roughly the same number as your SFPM! so with your pulleys and motor you will have a max SFPM of 3500. Enjoy your new grinder! Patrick

A full key way shaft would not deter me from threading the end, but that's me. Again you can do a partial key way on the shaft with out a mill. pulley sizes do not matter as much as the relative size between them. Your looking for ratios. A 2" 3" 4" has circumferences of 6.28, 9.42, 12.56. So a 2" to 4" is a 2/1 ratio and would roughly cut your motor RPM in half reverse that and it will double it. what is too fast or too slow is influenced by the circumference of your drive wheel. Bigger wheel more Surface feet per minute. Patrick

Well besides having a machine shop or a friend with the right tools to modify a shaft, You could do some simple things to make it work. Mark and center punch the end drill and tap. having the hole perfectly centered will not have a significant effect on balance so it is ok to do this all this with basic power tools and hand taps. Key ways on shafts are typically done on a mill, but there is not a lot of shear force on a grinder setup so the full strength of a proper key is not really required. One way to make a simple key is to place the pulley on the shaft drill and tap a hole between the two items. 50/50 just like a key, Install a bolt with some locktite. It will do the job just fine. If the pulley has an offset Hub you can install a pair of set screws. If it does not you can sometimes come in at an angle from the side and get your set screw in that way. There is also a Locktite designed specifically for things like this. It can fill a reasonably gap too. You put it on the shaft and the bore and assemble and let sit for 24 hours. You can also take a small cut off wheel or dremal tool and cut a key into the shaft. It does not have to be pretty. Patrick

I have been putting a lot of thought into studying it. I believe that there are two zones they occure most strongly between the point where the work contacts the belt and the drive wheel. As the drive wheel turns it is pulling the belt through the resistance of the work so this is the higher tension side. On the other side leaving the drive wheel and being fed to the work is the lower pressure side. I made my drive wheel the tracking wheel thinking to help avoid the top wheel design issue. I would put it on the bottom wheel so that it acts as both tension and tracking, but it is on the freaking floor hehe. It makes sense to me though that that could offer improved tracking. Bader space savers track from the contact wheels which is similar to tracking from the drive wheel. If I had a way to adjust the tracking from the bottom wheel that would be ideal , but its just not convenient DOH... I am re-cutting the drive wheel this weekend. Will post results on performance changes... Patrick