08-24-2022, 06:21 PM
(This post was last modified: 08-29-2022, 06:47 PM by Terry Bentley.)
Chapter 115
For rest of this week Steve had band practice. That gave me an idea and seriously hoping it would pan out. Since I really needed to get a few more of the carburetors modified, was thinking about asking Mr Sadeskey of possibly using metal shop for the next couple of mornings.
When I first showed him those intake parts, he was more focused on my modified carburetor. He held on to it and passed the carburetor back and forth between his hands a few times before finally setting it back down on the desk. If I could work on these at school, that would help out a bunch getting us closer to having everything finished.
So this morning I did come prepared just in case the shop teacher would allow me to work on them. I brought with me the three carburetor bodies already stripped down to the bare casting. In a small box were the necessary reamers I had used to bore that first one out.
This worked out great. Mr Sadeskey was thrilled about helping me out today. Not only did he stick around most of the morning, I finally got the instructions from him on operating the lathe. Now I know for sure how to use the automatic feed. No more guessing what the controls and all those levers actually do. He also explained to me how to cut threads. How cool is it to do that? I thought it was so awesome.
Another thing I was instructed on is some good insight about setting up to modify the carburetor bodies several different ways. One way is by swapping the tooling until each body is finished. Or setting up each tool and swap out the bodies one at a time until they are all finished. There was still another way he tried to explain was without even using the tail stock for every tool change.
These larger drill bits and reamers I brought from home have a number 3 Morse taper that fits into a much larger tailstock than what works in my tiny little lathe. The only way I could use these is by supporting the end with a dead center in tail stock then keeping it in place by pushing against the carburetor body. I had to use a Cresent wrench on the Morse taper tab to keep it from rotating.
Mr Sadeskey showed me a tool holder that these tapered end reamers would fit into and make it easy to use on the top slide. Also known as a compound slide. This could allow me to set up each reamer and do the same to every carburetor before changing out to the next tool. Even set up another tool in the talistock ready to use in the next step. More like semi mass production. Well sort of something like that.
Today was spent mostly learning several different ways to achieve the same results. It sure opened up my eyes on how to do things in the future. With the little bit of insight Mr Sadeskey showed me, I can apply it to so much more than just when operating the lathe.
So this morning passed by really fast. But still impressed with what I have learned. Even tho I didnt really get any work done. I wonder if it is possible that tomorrow all three of these carburetors could be finished enough to take home? The only other thing needing to get done is cleaning up the machining marks with Emory cloth. I might also taper out the air horn more and do a better job blending it into the venturi.
One important thing Mr Sadeskey suggested is that I first focus on building a simple fixture before getting too involved with each of these carburetor bodies separately. This way I can cut way back on setup time. Since I didnt really have a good way to hold the carburetor body in place, this made perfect sense. Also manage to hold much more precise tolerances so all of these carburetors will be nearly identical to the finished one. My one prototype HL-66A.
Later when I get these bored out and back home, then drill out the fuel circuits to match the HL-93A carburetor I have used as a pattern to copy. If I can make a late afternoon trip to Gasset then maybe grab diaphragm kits and the newer style needles and seats. Then these carburetors should be good as new. If I modified them right, they will be better than new.
Before the first bell rang, Mr Sadeskey called it quits for the morning. I cleaned up the lathe and put all of the tools back in the crib. He motioned for me to follow as he walked over to his office. A few rough sketches were drawn up by him for a simple fixture.
His sketches left a lot to be desired. His hands were shakey and didnt help for me to decipher his rough ideas for a fixture to build first. He suggested taking some measurements after I get home to make sure the fixture would also work on my lathe. This is something I never would have thought about.
He then told me to hit the tool crib and dig thru a pile of scrap and drops of aluminum. Just to see if I might find something that could be used to make the fixture. He had sketched some general ideas, but it was my turn to make the idea into something real. I grabbed a piece of round stock and a few small pieces of aluminum plate. Looked to be about 5/16 inch thick.
I sort of had a vague idea of something in my head, but not anything yet really jumped out at me in the pile of aluminum scrap. I kept thinking about a flanged piece that could be chucked up in my little lathe. But still large enough to be strong. My mind was trying to figure out a simple way for the carburetor body to run true each time it was mounted to the fixture.
The two 1/4 inch studs would hold the carburetor down just fine, but no way with the hole size in flange would it be exact each time a carb body was changed out. I kept thinking but nothing came to mind. One problem I was having is bolting the body down and still have enough clearance not to interfere with the mounting screws. On the large flange is not the problem. But to enlarge the throttle bore, the carburetor has to be mounted on the air horn side. That has a very small bolt pattern.
That one long tapered reamer I am using for the finish size of throttle bore will go all the way thru the carburetor. So this fixture has to be open for the tapered reamer to clear. Maybe I can keep an open mind and stumble on something during drafting class. Or during the day. Then try to make some headway tonight at home. The one thing that kept coming back to haunt me is knowing the bolt pattern on flange is not exactly centered to the throttle bore. I mean it is close, but not perfect. I guess it doesnt really have to be.
Improvising on that first carburetor, I made amends and kept working on setup with the realization nothing was exact. So the carburetor was mostly centered to the throttle bore or air horn. The first carburetor that was in a previous life, one HL-66A, has an offset venturi. Who ever Frank paid "serious coin" to as he put it, managed to drill it out way off center. But that is all they did to his carburetor. Just roughed it out with a drill bit.
On these next carburetors, I would like them all to match. But if that is not possible, then they might end up being offset too. In the dark reaches of my brain, I am picturing a flat plate with two bolt patterns drilled. One that fits the mounting flange, and the other bolts up to the air horn. Next I just have to figure out a simple way to attach this mounting plate to something chucked up in the lathe. So far sounds easy enough. But not so simple to get a good clear picture of it in my head just yet.
I had a small pile of scraps by the time the first bell rang. Still there was plenty of time before having to get across the hall, so not too worried. Mr Sadeskey almost scared the life out of me right as the first bell was ringing. I had my back turned to him as he walked in the very narrow tool crib. Without even realizing what he had done was already asking if I planned to be here tomorrow morning. Then he told me he could be here earlier than 7:00 am if it might help me out.
Thinking about being up here at school any earlier sounded so strange right then. I was barely awake at 6:30 when Steves dad would drive over to pick me up and take us to school. But if I could manage to get here that early to use the shop would be so awesome.
I told the teacher that 7:00 was just about early as I could make it, since relying on someone else to get here. But thanked him for the offer just the same. He scanned over the pile of craps I had gathered, then smiled. Yes I think you might have a good idea there. Cant wait to see how your fixture turns out when finished.
Well that is a surprise. I dont yet have a clue about what the fixture will look like. Just going from his vague rough sketch. Something which I still dont have a full grasp on just yet. The second bell was now ringing so I needed to boot on out of here. Sure would like to know what Mr Sadeskey has in mind, so I am not as much in the dark on this fixture.
For rest of this week Steve had band practice. That gave me an idea and seriously hoping it would pan out. Since I really needed to get a few more of the carburetors modified, was thinking about asking Mr Sadeskey of possibly using metal shop for the next couple of mornings.
When I first showed him those intake parts, he was more focused on my modified carburetor. He held on to it and passed the carburetor back and forth between his hands a few times before finally setting it back down on the desk. If I could work on these at school, that would help out a bunch getting us closer to having everything finished.
So this morning I did come prepared just in case the shop teacher would allow me to work on them. I brought with me the three carburetor bodies already stripped down to the bare casting. In a small box were the necessary reamers I had used to bore that first one out.
This worked out great. Mr Sadeskey was thrilled about helping me out today. Not only did he stick around most of the morning, I finally got the instructions from him on operating the lathe. Now I know for sure how to use the automatic feed. No more guessing what the controls and all those levers actually do. He also explained to me how to cut threads. How cool is it to do that? I thought it was so awesome.
Another thing I was instructed on is some good insight about setting up to modify the carburetor bodies several different ways. One way is by swapping the tooling until each body is finished. Or setting up each tool and swap out the bodies one at a time until they are all finished. There was still another way he tried to explain was without even using the tail stock for every tool change.
These larger drill bits and reamers I brought from home have a number 3 Morse taper that fits into a much larger tailstock than what works in my tiny little lathe. The only way I could use these is by supporting the end with a dead center in tail stock then keeping it in place by pushing against the carburetor body. I had to use a Cresent wrench on the Morse taper tab to keep it from rotating.
Mr Sadeskey showed me a tool holder that these tapered end reamers would fit into and make it easy to use on the top slide. Also known as a compound slide. This could allow me to set up each reamer and do the same to every carburetor before changing out to the next tool. Even set up another tool in the talistock ready to use in the next step. More like semi mass production. Well sort of something like that.
Today was spent mostly learning several different ways to achieve the same results. It sure opened up my eyes on how to do things in the future. With the little bit of insight Mr Sadeskey showed me, I can apply it to so much more than just when operating the lathe.
So this morning passed by really fast. But still impressed with what I have learned. Even tho I didnt really get any work done. I wonder if it is possible that tomorrow all three of these carburetors could be finished enough to take home? The only other thing needing to get done is cleaning up the machining marks with Emory cloth. I might also taper out the air horn more and do a better job blending it into the venturi.
One important thing Mr Sadeskey suggested is that I first focus on building a simple fixture before getting too involved with each of these carburetor bodies separately. This way I can cut way back on setup time. Since I didnt really have a good way to hold the carburetor body in place, this made perfect sense. Also manage to hold much more precise tolerances so all of these carburetors will be nearly identical to the finished one. My one prototype HL-66A.
Later when I get these bored out and back home, then drill out the fuel circuits to match the HL-93A carburetor I have used as a pattern to copy. If I can make a late afternoon trip to Gasset then maybe grab diaphragm kits and the newer style needles and seats. Then these carburetors should be good as new. If I modified them right, they will be better than new.
Before the first bell rang, Mr Sadeskey called it quits for the morning. I cleaned up the lathe and put all of the tools back in the crib. He motioned for me to follow as he walked over to his office. A few rough sketches were drawn up by him for a simple fixture.
His sketches left a lot to be desired. His hands were shakey and didnt help for me to decipher his rough ideas for a fixture to build first. He suggested taking some measurements after I get home to make sure the fixture would also work on my lathe. This is something I never would have thought about.
He then told me to hit the tool crib and dig thru a pile of scrap and drops of aluminum. Just to see if I might find something that could be used to make the fixture. He had sketched some general ideas, but it was my turn to make the idea into something real. I grabbed a piece of round stock and a few small pieces of aluminum plate. Looked to be about 5/16 inch thick.
I sort of had a vague idea of something in my head, but not anything yet really jumped out at me in the pile of aluminum scrap. I kept thinking about a flanged piece that could be chucked up in my little lathe. But still large enough to be strong. My mind was trying to figure out a simple way for the carburetor body to run true each time it was mounted to the fixture.
The two 1/4 inch studs would hold the carburetor down just fine, but no way with the hole size in flange would it be exact each time a carb body was changed out. I kept thinking but nothing came to mind. One problem I was having is bolting the body down and still have enough clearance not to interfere with the mounting screws. On the large flange is not the problem. But to enlarge the throttle bore, the carburetor has to be mounted on the air horn side. That has a very small bolt pattern.
That one long tapered reamer I am using for the finish size of throttle bore will go all the way thru the carburetor. So this fixture has to be open for the tapered reamer to clear. Maybe I can keep an open mind and stumble on something during drafting class. Or during the day. Then try to make some headway tonight at home. The one thing that kept coming back to haunt me is knowing the bolt pattern on flange is not exactly centered to the throttle bore. I mean it is close, but not perfect. I guess it doesnt really have to be.
Improvising on that first carburetor, I made amends and kept working on setup with the realization nothing was exact. So the carburetor was mostly centered to the throttle bore or air horn. The first carburetor that was in a previous life, one HL-66A, has an offset venturi. Who ever Frank paid "serious coin" to as he put it, managed to drill it out way off center. But that is all they did to his carburetor. Just roughed it out with a drill bit.
On these next carburetors, I would like them all to match. But if that is not possible, then they might end up being offset too. In the dark reaches of my brain, I am picturing a flat plate with two bolt patterns drilled. One that fits the mounting flange, and the other bolts up to the air horn. Next I just have to figure out a simple way to attach this mounting plate to something chucked up in the lathe. So far sounds easy enough. But not so simple to get a good clear picture of it in my head just yet.
I had a small pile of scraps by the time the first bell rang. Still there was plenty of time before having to get across the hall, so not too worried. Mr Sadeskey almost scared the life out of me right as the first bell was ringing. I had my back turned to him as he walked in the very narrow tool crib. Without even realizing what he had done was already asking if I planned to be here tomorrow morning. Then he told me he could be here earlier than 7:00 am if it might help me out.
Thinking about being up here at school any earlier sounded so strange right then. I was barely awake at 6:30 when Steves dad would drive over to pick me up and take us to school. But if I could manage to get here that early to use the shop would be so awesome.
I told the teacher that 7:00 was just about early as I could make it, since relying on someone else to get here. But thanked him for the offer just the same. He scanned over the pile of craps I had gathered, then smiled. Yes I think you might have a good idea there. Cant wait to see how your fixture turns out when finished.
Well that is a surprise. I dont yet have a clue about what the fixture will look like. Just going from his vague rough sketch. Something which I still dont have a full grasp on just yet. The second bell was now ringing so I needed to boot on out of here. Sure would like to know what Mr Sadeskey has in mind, so I am not as much in the dark on this fixture.