JV Puleo

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Posts posted by JV Puleo

  1. Here's the flywheel end of the crankshaft. In looking at this again (it's been years since I really looked closely at it) I suspect the thrust should go on the rear bearing.




    With the cap in place.




    And the flywheel itself. It's massive... 16" in diameter and I think it weighs about 75 lbs.




    The clutch surface on the inside of the flywheel.




    I did get some work done as well. The cap studs all threaded. I now have to drill the holes for the cotter pins and they are finished.



    • Like 2

  2. 3 hours ago, edinmass said:

    ... just a case of an inexpensive engine design, that was meant to only last a short time. With all of your upgrades, I expect it will last several lifetimes when your done with rebuilding it. I’m looking forward to it’s “coming out” party..........maybe next year?🤔👍


    I hope it's next year...making the connecting rods will be a challenge but they are the last major component I've yet to start and I've given the process a good deal of thought.

    I'm in complete agreement with your assessment. I suspect the major problem was that the company was committed to a price and had to cut every possible corner in order to meet it. Only the fact that they had limited choices for materials has left us with something to work with. If they had pot metal they would have used it everywhere.


    Mitchell-Lewis claimed to "make everything themselves" but I seriously doubt it. Some of the chassis components, notably the axles and rear end are quite well made and I know they didn't make the springs because the maker's name is on them, albeit in a place where you would never see it unless you took them apart.  The frame itself is very conventional and, to my mind, a bit flimsy but I think that can be addressed readily enough.


    Tomorrow I'll get some pictures of the flywheel and the mounting flange.

    • Like 1

  3. The studs trimmed to the final size. After I did this I also put a chamfer on both ends.




    Then I put each of them back in the lathe and cut a groove at the end of the thread. This material is too tough to thread with just a die in the die holder. The pressure needed to turn it makes the stud slip in the collet. My idea is to single-point them about 3/4 of the way and then finish with a die. It doesn't thread smoothly either so I'd have to run a die over the finished part just to get rid of the burrs.






    I cut the threads on the first one .020 deep and used the die holder...




    It worked but it was very tough going. On the second one I cut them, .025 deep which is very close to what is supposed to be the finished thread depth. This time it worked perfectly with the die taking off just enough to smooth the threads up.




    You can see the two finished studs at the bottom.


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  4. I doubt there is anything holding the two halves of the brake drum together aside from the bolts in the middle. It's a conventional "machine" part of the day. I think the surfaces of the two halves were probably ground and then carefully fitted together and turned on a mandrel so the OD would be concentric. It may be that the hole in the center was smaller at first and that it was bored with the two halves bolted after which the OD was turned. If they were going to add further support, I suspect there would have been through bolts in the center web at the outside extremities of the circle.

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  5. I did a little reading on bolts last night, looking up the SAE recommendations in the 1926 handbook. The steel recommended for bearing studs and bolts had a tensile strength of 80,000 PSI. According to the McMaster Carr catalog, the tensile strength of grade 5 is 120,000 PSI so I think I'm safe using it. Finding the appropriate rod stock was, however, difficult so I decided to make the studs out of grade 5 bolts. Fortunately, I had 10 so I went out and bought a few more. I cut the heads off first.




    Then set them up in the lathe to turn the threaded portion of the bolt down to the length of the longer part of the prototype stud I'd made.

    I set a stop on the lathe bed and used the nut you see as both a stop and to smooth out the burrs on the end after turning them.




    With that done, I marked each one with a cut off tool and then sawed off the extra metal. These are too long, of course, but tomorrow I'll trim the ends and, hopefully, thread them.



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  6. I'd be interested in calculating the heat but ultimately there isn't much I can do about it since I'm not designing the engine – just trying to do the best job I can rebuilding it. The options available are limited by the dimensions of the parts. That said, I've worked on enough good quality engines of the period to have a feel for them so I doubt that whatever the final dimensions of the shells are they can be far off. One of the reasons I wanted an oil filter (actually all I have is a very fine screen) as well as an air filter is to get away from the obvious problem these cars had when made, aside from those that weren't helped by the lubricants of the period or the very common practice of putting used oil in a settling tank and re-using it. I have several period plans for such tanks and you can bet that many of these cars got the used oil as soon as they were "old and worthless" - which came a lot sooner then than it does now. I did just order a book... Bearing Design and Application by Wilcox and ? (I forget the second author) published in 1957. Hopefully it will have some worthwhile data.

    I'm more concerned about getting the crankshaft thrust right. The crank does not seem to have very substantial thrust surfaces and, because they are radiused, it will be difficult to measure. But, we keep chipping away at the problems and eventually it will come together.

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  7. I believe the thrust has to be on the center bearing. I think it was there from the visible wear and that bearing gives me the largest amount of leeway for adjusting the width. I've yet to discover what the optimum thickness for the Babbitt should be but I'm thinking between .040 and .060. I've seen this figure somewhere but at the moment can't remember where. As to heat transfer...that is closely related to how tight the shells fit the bored crankcase. If contact is very good, the heat transfer will be. Thankfully aluminum dissipates heat very well so it may not be quite as critical were it an iron crankcase but putting in a slip of paper to shim up a shell is a big mistake since it acts like an insulator.


    The flywheel is conventional, bolting to a flange on the crank. It is very large as the car has a cone clutch so not much can be done about lightening it. Actually, I think it has already been skinned because there are no timing marks on it and there should be.


    [EDIT] Interestingly, some time ago I discussed this with a friend (a Packard guy) who has many years experience with engineering and machine design. He suggested that, with good lubrication, the correct clearances and given the relative slowness of the engine, it would probably work with just bronze bearings. I've actually seen period references to engines made that way but it isn't something I'm prepared to experiment with...maybe some day but I've too much time invested in this to be trying an experiment like that.

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  8. RR used those thick shims with a Babbitted edge as well but there we no additional shims. I notice that the Wisconsin uses dowel pins to locate the caps perfectly. I wonder if I should do that too. I don't think that with modern oil and an air cleaner the bearings are apt to wear enough to ever have need for the shims. Were I to put them in it would only be to adjust for my boring...never having done that before I wonder if I can get it perfect on the first try. But, I plan to make a st of aluminum bearings as a practice run and to use them to hole the crank when I'm working on the connecting rods so I'll get a chance to see if I can hold a tolerance of less than a thousandth.

    • Like 1

  9. This post is a question for Edinmass... or anyone else with experience doing this sort of thing.

    These are the bearing caps. They have a projection on each side...




    When they are bolted down, the projection does not touch the crankcase leaving a gap between the two halves of the bearing.




    Presumably, this was to allow the bearing to be shimmed and tightened up by removing a shim or two but the result is that the two halves of the bearing are not in contact. I plan to bore these out and fit bronze inserts that will be Babbitted - the original Babbitt is very thick – almost 1/4" – so there is room for that. But, I don't like the idea of having the two halves of the bearing not in contact so I'm wondering if I should include a provision for shims...maybe removing the projection from the cap and surface grinding it flat. If it was then bored with the shims in place the hole would be round and there would be a small amount of adjustment. Ideally, I think I should dispense the shims but I'm not certain. It would then be necessary to do a perfect job of boring the main bearings leaving no room for adjustment.

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  10. Yes. I think that might be the first component that is completely done. If it isn't, it's one of the first.

    The studs to hold the bearing caps are proving to be more off a headache than I'd anticipated. It turns out the material I wanted to use isn't available as 7/16" rod. So, I went back to my 1926 SAE handbook and looked up what they recommended for this purpose. It turns out that Grade 5 is probably the right thing so tomorrow I'll see if I can get some bolts that I can make the studs from. I have found matching castle nuts, albeit rather expensive (for nuts)...I guess 7/16 is a size that isn't used much any more especially in the fine thread.

    • Like 1

  11. Since I'm waiting for the materials to make the studs for the bearing caps I took the water pump apart for, hopefully, the last time to clean out as much of the lapping compound as I could and put in new seals. I doubt the old ones would have leaked but it is hard not to damage them when prying them out and they are relatively cheap so it seemed the prudent thing to do.




    I then greased it with the water pump grease I bought in England and plugged the front grease hole with a 3/8-16 grub screw.




    I now get to put it on the shelf and forget about it until I assemble the engine.

    • Like 7

  12. 19 hours ago, 1912Staver said:

    I had also forgotten that your car also used a sub frame. Interesting that there is not as much distance between the main frame and the sub frame as I am used to seeing.  


    I thought to measure the sub-frame as I was leaving yesterday and realized it it 21" wide so it does not follow the SAE guidelines - which explains whey it looks to be closer to the main chassis rails. It is!



  13. I think the early car makers were madly in love with aluminum. Given the low power of early engines saving weight was critical. My pre-1900 Panhard had a number of aluminum parts, including the transmission case. Looking at it with hindsight, it was very poor quality material - of course not to them but it simply hadn't been available in commercial quantities long enough for anyone to have a good idea how it would stand up in use and, of course, no one, then or now was building a car to last 100 years. It's interesting that by 1912 it was acknowledged that it was a poor material for holding threads and makers were encouraged not to use it that way. They did, but for reasons that had nothing to do with long-term reliability. I'd be more critical were it not that I've had a couple of experiences with modern cars (i.e. built in the last 10 or 15 years) that did exactly the same thing, with the same results, and that is with the advantage of hindsight and modern metallurgy.

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  14. I have two browsers... the other one is Safari. It doesn't work at all with this site although again, it works with every other forum I visit. Chrome won't load because the operating system is too old and can't be updated. If it comes to buying another computer or dropping this site I'll be out of here. As it is, it works although whether it will continue to work is a question.

  15. My default setting for finding odd industrial products is ebay. In fact, it's about all I use it for these days. fortunately, a lot of the stuff I'm looking for has a very limited market so you can find some bargains. A week ago I searched for a 1"-20 bottoming tap...which I need for exactly 1 hole. The cheapest was 14.20 + shipping, a very good buy. I wondered if the person who listed it made a mistake though because they seemed to be offering 6 of them for that price. I bought it...thinking it was cheap for even 1. This is what I got...




    So if anyone needs one... I've got extras.


    I planned to make the studs for the main bearing caps today. Much to my surprise - because it isn't like me, I forgot to get the materials. I went ahead and made 1 as they are a bit fussy and it might be a good idea to work the dimensions out ahead of time rather than make 12 and then decide aren't right.




    The tricky part is drilling a hole for the split pin in exactly the right spot. I was thinking of making a tool and remembered I had one - made some time ago when I was making the rockers.




    I think I got the hole a bit too low. I can adjust that but I'd better wait until I have the nuts and washers.



    • Like 2

  16. Every time I sign into this forum I get this message...regardless of whether I'd signed in only 5 minutes ago.

    Two things are happening here. I have checked the "remember me" box which doesn't seem to work...it almost never remembers me.

    When I get the message below, I click the "forums" tab which then connects me and I am signed in so there is obviously something wrong. And, yes I have cleared the cache and this is happening all the time on both my home and office computers.



  17. Done. I tried all the caps and they fit just fine but this was a serious tension inducing job. Now I'll make the studs. Interestingly, I had a bit of a search to find grade 5 castellated nuts. The grade 2's are available everywhere but it is desirable to match the nut to the stud or bolt. I'm making the studs out of Stressproof which has just about the same tensile strength as grade 5. With four 7/16 studs on each cap there is no need to go to grade 8 - the original bolts were about as hard as soap.




    The only holes I'm not putting inserts in are those for the studs that hold the blocks and the lifters. In both case there is room inside the engine for a lock nut...those will be castellated as well.

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  18. Here is the Jackson crankcase. It's a bit heavier than the Mitchell and, I think, a bit more robust. The camshaft goes in on the side where it is resting. Notice that the gear that drives the camshaft, and the gear that drives the magneto are inside the case. There is no timing cover, nor is there it big intermediate timing bear.




    I started on the Mitchell today by chasing the threads in the original holes for the main bearing studs. This is just so that the centering tool will screw in easily. One of the reasons I'm doing this (aside from the fact that this old aluminum is not very strong) is that the Mitchell method of securing the studs was to cut a slot in the end and, after they were in, to spread them with a chisel. They were a bear to take out and in doing so it was clear that unscrewing them was damaging the threads. Would they work? probably - as there are 4 of them on each cap but I really didn't like it and I know I'd be worried that they might come loose.




    I put the crankshaft in the case to see how it fits. Converting this to bronze shells is a fairly complicated job and I wanted an idea where I was going. I's probably been close to 8 years since I took it apart. This is the front bearing, the only one I'm really concerned with because the hole is rather close to the edge. I must have measured this thing a dozen times but, ultimately, decided to go ahead.






    Before I started on the case I drilled a hole in a piece of aluminum to test the end mill and the tap...just in case I made an error somewhere. It's better to find out now before I damage an otherwise unobtainable part.






    It seemed fine so I went ahead with the crankcase. In this case the centering fixture is a flat head socket cap screw that has been center drilled. I used this to line the hole up with the spindle.




    I then bored it with the end mill, threaded it without moving anything and screwed the insert in. By the end of the day, I'd done 4 of them, including one of those I was worried about.




    So far, so good. I should finish this tomorrow and then make the studs that will hold the caps down.

    • Like 3

  19. Well...I'll be happy to help in any way. Perhaps I should measure the crankshaft so you can compare it to yours.

    You might also try to find some photos of a Jackson engine...it used the separate mountings for the cam and it has internal timing gears. I have a crankcase here and I'll take a photo.


    Oh... and the Mitchell is actually EOI - the exhaust valves are in the cages. They made no provision for valve guides so when the valves - or the guides wore it just leaked.



  20. I installed the inserts this morning... you can see how some are proud of the surface. This was to make them come out square with the cast bosses on the crankcase which aren't terribly uniform.




    Then they were filed flat. I took my time with this because I am not terribly good with a hand file and I did not want to mar the flat surface. As it is, it has plenty of dings and machining marks...it wasn't a perfect surface to begin with but I didn't want to make it worse. Since the sump will get a rather thick paper gasket the little marks aren't important.




    Then, just to be sure I set the sump on the crankcase. The holes seem to all line up although it isn't perfect. I suspect that may be the result of Mitchell's lack of precision in their machine work. Fortunately, the ears where the heads of the bolts go are quite large so I may enlarge the holes 1/64... but I'll clean everything up first. As it is, the sump is dirty and that may have kept all the bolts from sliding in perfectly. As a matter of curiosity, the sump is cast iron and weighs almost as much - if not as much as the crankcase. It is not what is illustrated in the original owner's manual and I suspect that, after the fact, the company decided that they needed an iron sump to stiffen the crankcase. They would have been much better advised to make the crankcase of iron and the sump of aluminum but I'll bet the decision to change the design came late in the game.




    The threaded hole in the front of the sump is how you check the oil. This engine pre-dates the invention of the dipstick. You poured oil in until it came out of the hole. The raised section on the bottom of the sump is an oil galley. I'm guessing there were petcocks there to drain it but why were there 2? In any case, it is a handy ting to have because I am going to have to think of a way to drain oil from the timing gear case. Mitchell made no provision for lubricating the timing gears aside from packing the case with grease. Since centrifugal force with throw the grease against the inside of the case that is a poor idea at best and I'm going to have to think up a way to get oil in there and out again.

    • Like 4