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My 1910 Mitchell "parts car" project


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Well...it seems to have almost worked. Most of the crack is closed up and solid now but there are some pinholes where the silver solder apparently didn't take. I have an idea how to deal with that so I'll keep you posted.

 

 

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That high end pump paint will seal pinholes and improve cavitation, and stop any future rust. If only minor, I would leave well enough alone. The flower pot brought a smile to my face. Looked brand new..........

 

White pump assembly will take place this week..........👍👍👍👍👍

Edited by edinmass (see edit history)
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That's my thinking exactly. The crack does seem to be firmly closed so I do not want to take a chance on reheating it. I may try  using soft solder on the V groove. Terry H sent me a clipping from a turn-of-the-centuury machinist's magazine that discussed fluxes for cast iron. The one recommended is Zinc Chloride - Zinc Oxide dissolved in Hydrochloric Acid. That easy to make and I think would be worth a try with the pump sealer painted on the inside.

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I agree.......absolutely no more heat. I can’t remember the name of the pump paint......it’s asinine what they charge for it. Fantastic stuff...........getting a divorce is less expensive. With a non pressure system, almost any pump paint should work. You could even use an epoxy paint......and that would solve the issue. For the next five owners lifetimes.

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Posted (edited)

I started cleaning up the flux residue on the Cadillac pump this morning and took a better look at it. The crack is closed up nicely and appears to be firm. The headache is that with this long crack the silver solder did not fill every void so there are tiny leaks all along the crack. I'm going to use soft solder on it...it won't get hot enough to disturb the silver solder and I hope the lead/tin solder will flow into the voids. Then, I've ordered some two-part epoxy sealer paint that I will use on both the inside and outside of the pump. I will be surprised if that doesn't do it...

 

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But, to break the day up I worked on the radius rods. I put a groove in each sleeve about 1/4" wide and .015 deep. I will drill 1/4" holes through the tubing that align with the groove. The idea is that you can't braze well into a blind hole. Hopefully, when the end of the tubing is heated, the braze will flow around the sleeve and out the hole on the other side, in which case I'll know it took all around

 

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I set the tubes up in the drill press to drill..

 

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And after the 1/4" holes were in, drilled and reamed the ends for the sleeves.

 

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This is what they look like...but as I neared the end of this it occurred to me that I have no idea how much strain will be placed on the radius rods and wondered if this was sufficient ...so tomorrow I'm going to put another groove in the sleeves and another hole in each end of the rods so that each sleeve is brazed in two places. As far as I can tell, this appears to be how the original were made. All this came about because on Sunday I helped my brother-in-law remove a bushing from a front stanchion on the 1946 BSA he's putting together. He had to cut one of the fork tubes off and I brazed a threaded bushing into it so we could improvise a puller and get some real pressure on it...it worked but the first time around it literally pulled the bushing out of the tube.

 

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Edited by JV Puleo (see edit history)
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Excellent work on the pump Joe! It really demonstrates how a little patience, skill and research allowed you to use the "small hammer" rather than go straight to the "big hammer" approach. And of course saved a part that many would have scrapped. Simply fantastic!

 

T

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Posted (edited)

Well...it isn't done yet but I think it's getting close. The article you sent me about soldering cast iron was an eye opener. I'm going to make some of the zinc chloride flux...in fact, I bought 2 pounds of zinc oxide so I'm well equipped. Aside from the cast iron, it is also what I think I need for the cartridge core radiator I plan to make. I knew they used a liquid flux but none of the old descriptions said what it was, probably because it was assumed everyone knew.

Edited by JV Puleo (see edit history)
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Phosphoric acid is an extremely good soft soldering flux on stainless steel, copper, brass and other similar materials.  also very good for tinning soldering irons.

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Thanks, I didn't know that. It may be much easier to work with than the zinc chlorate, which, I understand, is very aggressive.

 

I cut an additional groove in each threaded liner for the radius rods toady and drilled the added holes...

 

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Then brazed the first one in place. As I'd said, I'm not good with heat - largely due to lack of practice and not very good equipment. It's messier than I'd like...

 

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But I put it back in the lathe and cleaned it up. It looks good but I still worry if it's strong enough. Needless to say, I had another idea - too late to act on it - of threading the inside of the tube and screwing the sleeves in – then brazing. That would be stronger but I've got to stop obsessing about these things...I'll do that if one of them fails, which I still think is unlikely.

You can just see the brass in this photo after cleaning the end of the rod up.

 

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I spent the afternoon finishing up the radius rods even though I still have reservations about the design. I'd stop and do it over but the tubing was expensive and I'm still unsure how much stress they are under. In any case, to remove the bulk of the messy braze I set the rod up in the lathe, indicate it, and turn it off being very careful not to take more than .001 or .002 off the tube itself. Then I finish it up with files and emery paper. They are no longer perfectly round but you'd have to put a micrometer on them to tell.

 

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I also made some zinc chloride flux. It's just Muriatic acid and zinc oxide mixed 5:1. I squirted a little in the hollow radius of the pump thinking I'd like to be able to flux it from both sides. I then rolled it around being careful to keep it in the castings...and it didn't leak at all! Then I tried the same thing with water and it didn't leak. When I tested it on Sunday, and notice some small leaks, I had used Acetone. It now looks as if my silver solder job came out better than I'd thought. If Acetone will pass through the crack but water won't the voids must be extremely small. I will still fill the V groove with soft solder and I bought some two-part epoxy paint made for marine use. After it's soldered, I'll paint the inside and outside of the pump with it and I think we're home free. With luck I'll have the pump back together next week.

 

The information I have for silver solder says it works best with a maximum gap of .001 to .0015. The fixture I made to clamp the housing and close the crack must have been essential to getting the optimum gap.

 

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I'm back to the Cadillac water pump...today I drilled and tapped the hole for the drain...

 

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And then went about filling the V groove with solder. I'm doing that to two reasons...if the solder sticks its a further seal. Also, if it works well, the crack will be invisible after the pump is painted. It is easier said than done and never having soldered cast iron there is a learning curve. The zinc chloride flux seems to work reasonably well but I'm having problems getting an absolutely smooth joint. That said, I'm getting better at it. Chances are I'll finally figure out how to do it when the job is almost finished. I got about 1/3 of the way around...

 

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I'll plug away at this tomorrow...

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8 minutes ago, Terry Harper said:

Looks great Joe!

 

Not many people would take this on!


Joe thrives on self abuse.........just look at the White gear and shaft!

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Posted (edited)
1 hour ago, Terry Harper said:

Looks great Joe!

 

Not many people would take this on!

 

Maybe treat the soft solder almost like "body lead" maybe try using wooden paddles to smooth it? then file etc. to final shape?

 

That's a good idea. I also have some metal filler called "Thermo Seal" and I just thought of a way of applying it to the inside surface where the crack is the worst. I'm pretty confident this whole job will be done next week. This one is important to me because I like the gentleman who owns the car - he bought it largely on my approval and, even though he has a Model t - has never worked with a big early car. As we know, this is a different kettle of fish and I think it's important that he not be driven off by an insurmountable problem. In any case, I also like these early Cadillacs and, if the stars were aligned correctly, would be tempted by one myself. So too, there is value in working out a solution to a problem. You never know when that may come in handy in the future.

Edited by JV Puleo (see edit history)
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13 hours ago, JV Puleo said:

 

That's a good idea. I also have some metal filler called "Thermo Seal" and I just thought of a way of applying it to the inside surface where the crack is the worst. I'm pretty confident this whole job will be done next week. This one is important to me because I like the gentleman who owns the car - he bought it largely on my approval and, even though he has a Model t - has never worked with a big early car. As we know, this is a different kettle of fish and I think it's important that he not be driven off by an insurmountable problem. In any case, I also like these early Cadillacs and, if the stars were aligned correctly, would be tempted by one myself. So too, there is value in working out a solution to a problem. You never know when that may come in handy in the future.

Early V8 Caddy would be nice. However, I keep leaning towards a series 10 or series 9 Franklin  - preferably a touring car. No the most powerful but good quality, reasonable prices and very interesting engineering. Unfortunately other priorities mean will be a dream for a long time.

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That's my feeling too...I like the mid-20s Franklins as well. Realistically though, given my age and very limited storage and work facilities at home, the most I can hope to acquire is one more car... My first (realistic) choice would probably be a 20 HP RR followed by a Franklin or Cadillac. But, I'm thinking it may be another 5 years before I can build a garage, by which time I'll be in my mid-70s. There is a limit to how much heavy lifting any of us can do so another project like the Mitchell is out of the question.

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Hello joe

i may be mistaken but I believe your radius rods are furnace  brazed,I believe that’s the same way older motorcycle frames are assembled, if you look at an unrestored motorcycle frame you will probably see about the same finish,     Dave

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Yes...I thought that might be the case. If I could do that I'd be satisfied with the job but I'm thinking that to get the same degree of strength I should screw the inserts in. I don't think the brazing technique I used is anywhere near as good.

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Posted (edited)

I plugged the hole that connects the main casting to the original drain using some shipping "peanuts" to keep the filler in the hole and not in the water passage.

 

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Soldering the V proved tedious but I eventually got it done. After I did this I tested it by putting in a little water and rolling it around - keeping the water in the hollow section of the casting. There were no leaks.

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Then I wire brushed the inside of the casting as best I could. This has spent a week in Evaporust and was then boiled in lye so it should be free of oil...I'm not sure I could get every bit of rust but it looks pretty clean.

 

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Then I coated the inside of the casting with thermo-seal using a cake decorating tool to push it up against the surface where I couldn't get my finger in. It takes 7 hours to set so I won't be able to judge how well it works until tomorrow.

 

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When it's set up, I'll paint it. I've bought some two-part waterproof epoxy paint made for marine applications. I think that should secure it but I'll paint both the inside and the outside just to be sure. So far this repair seems to have been successful.

Edited by JV Puleo (see edit history)
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Here's what I hope is the last step in the water pump casting repair. I mixed some of the epoxy marine sealer using my postal scale to get the right proportions. It was thicker than I'd anticipated and had to be pored into the pump. I then spread it around with a cheap paint brush in the hope I got everything. Unfortunately, i can't see all of the water passage but it didn't leak before I put the sealer in so I'm pretty confident it can only help.

 

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It does seem to flatten out well. I did the inside first and then the outside but needless to say, I can't paint and take photos at the same time. I don't know how long it takes to set. The instructions give you 30 minutes working time but I'll let this cure at least over night as there is nothing else I can do to it today.

 

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Posted (edited)

When I arrived today the epoxy sealer was still a bit sticky. I want it to fully harden because I'll have to sand out some lumps where it ran a bit and, at this point, I see no compelling reason to rush the job. In a day or two it will be fine. I suspect the slow hardening has something to do with the temperature in the shop. I think if it as being warm - but it's really around 50 degrees...I'm just too adjusted to a NE winter. While it hardens I worked on the ends for the radius rods, first cutting 4 pieces of 1-1/2" square stock. The dimension is dictated by the largest dimension of the finished piece. They would have used a forging rather than machine this from a billet but I don't have that option.

 

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I calculated the location of the hole. On the finished pieces 1 hole is 5/8" and the other is 1/2". I will make them both 5/8 and bush the smaller holes as this will allow me to use the same tooling for all the pieces. I drilled center holes using the mill so I could place them exactly.

 

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And moved them over to the drill press to drill and ream.

 

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Most of the piece has to be turned down to 3/4" and threaded. To center the square stock in the 4-jaw chuck I indicated a piece of 1-1/2" round...

 

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Then I rotate the chuck so that the #1 jaw is at the top and loosen the #1 and #4. I always use the same jaws for this...the others don't move. It isn't perfect but this allows you to center the square stock within a few thousandths.

 

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I faced off the end - being very careful to take a cut of only about .010. The square stock won't go into the center of the chuck and that long projecting end is not ideal to put much pressure on. It did work and I was able to put in a center hole and start turning.

 

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It will take some time to get this down to 3/4" but I've no real choice if I want the make these in one piece. You can tell how straight you've made it by the relative width of the turned areas and their straightness. I was pleased with this because I can see no difference in the 4 turned areas...

Edited by JV Puleo (see edit history)
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Posted (edited)

Thanks Ed.

This morning I went back to the end for the radius rod...finally getting it round and then turning it down to 3/4". A 1-1/2" square is more than 2" wide at it's widest so this takes some time.

 

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Then put a chamfer on the end and cut the relief for the end of the thread.

 

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As set up the threading tool. At this point I discovered I had a problem. I can't run the thread into the relief like I usually do because the square, at its widest, will hit the tool. I was able to get very close but this means I won't be able to do the LH thread this way. But, as it was all set up, I went on and threaded it as best I could. I stopped when it was about .010 big and tried a chasing die. I should have gone a bit further because as soon as it was fully engaged it was a little bit tighter than I'd like. By then I'd taken it out of the lathe and you can't put it back and have it work.

 

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In order to get some leverage I put it in the mill vice and used a big box wrench on it...

 

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That worked fine but it was more effort than it should have been. Of course, in the midst of doing this I thought of a better method that, fortunately, will work just fine with the LH pieces so I'll make one more of these - so they match, and make the other end with the alternate method. Oddly enough, it will save me some money because I can use the left over pieces of square stock to make the adjustable tie rod ends I'll eventually need.

 

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By this time I thought I'd better take a look at the water pump...the marine sealer was dry now so I sanded out the lumps left by some runs and pressed in the center bearing using Locktite press fit to secure it.

 

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Then gave it a coat of primer. I certainly hope it doesn't leak - it LOOKS great - you can't tell it was ever cracked.

 

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On my way out the door I'll spray some black paint on it and tomorrow I hope to be able to reassemble it.

 

 

Edited by JV Puleo (see edit history)
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Posted (edited)

I've been reassembling the second water pump for two days now. You'd think it would be a snap but it actually takes quite a bit of fiddling to get it right when you don't have any of the jigs and fixtures, not to mention the new parts, that the factory had.

 

After I'd pressed in the large bushing I lapped the hole. This is because I replaced the other bushing which will, of necessity, be a bit smaller. because I only replaced 1 bushing in this pump, this job went better than the last time.

 

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Then drilled and tapped the impeller for set screws.

 

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And drilled the grease hole in the shaft.

 

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What should have been the last step was milling a flat for the set screws. This was near the end of yesterday and I should have quit because I made the same error I made with Ed's White water pump shaft and put the flat in the wrong place. Fortunately, in this case, it doesn't effect anything.

 

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I did have to go back to the mill 2 more times but I finally got the impeller set and put some Loctite on the screws.

 

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And a thrust washer on top. The thickness of the washer is critical because you need the impeller to turn freely and not hit either side of the casting. In both pumps the thrust washers were badly worn but, since that took 100 years, I don't think it's a problem again in the future. (At least not in my lifetime!)

 

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I put the pump together. Actually, I put it together and took it apart 3 times, each time addressing a small problem. It is critical that when everything is snugged up the shaft turn freely and that the impeller not rub anywhere. There's a good reason for that. When the packing goes in it will put some drag on the shaft. You cannot tell by turning it what is causing that so it's important to eliminate all drag first - then you can be sure you are only dealing with the packing.

 

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To pack it I used 3 layers of square graphite impregnated pump packing.

 

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And a modern lip seal.

 

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And there it is. I have two gaskets to make and I have to charge one of my grease guns with proper water pump grease and lubricate it. then, I hope, this job is done!

 

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Edited by JV Puleo
typos (see edit history)
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Posted (edited)

 

Making the gaskets I needed turned out to be easier than I'd anticipated but when I went to finish assembling the pump I realized I'd never cut reliefs in the plug I made to replace the water line to the carburetor jacket, nor had I cut down the stainless screws to attach it...so a 15 minute job because a 2 hour job...

 

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But...THEY ARE DONE! Or at least as done as they can be before we put them back on the car. I never relax until the car goes down the road but at least we're up to the point of putting them back.

 

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For the sake of reference - since it I started this back in September...here's where I began.

 

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All this was done by 4 PM so I started cutting some 1" pieces of hex stock to make oversize nuts for the radius rods.

 

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The Cadillac pumps were leaking rather badly from the start but I suggested to the owner, who was only running it around the lake at his summer house, that he wait until the weather turned before he had them out so, with the weather now warming up, it's the perfect time to reassemble it.

Edited by JV Puleo (see edit history)
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I cut 4 pieces of hex stock for the oversize nuts I need for the radius rods...then, started thinking about the set up. I actually need 8 oversize nuts. 2 RH and 2 LH in 3/4-16 and 3 RH and 1 LH in 7/8-18. The larger ones are for the tie rod, one of the problems I've been mulling over ever since I got the car. This is half of it...

 

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I have the other piece somewhere too but it was broken and, as you can see, made from tubing. It apparently wasn't very strong and someone "repaired" it by welding on a piece of angle iron.

 

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This won't do. I regard everything about brakes and steering as absolutely critical if the car is going to be safe to drive so I will make a solid tie rod. But, calculating the exact length and then making it is easier said than done. It has to be bent, the bends have to be absolutely parallel and it has to be somewhat adjustable to set the toe in. The solution I've come up with is to thread the ends where they attach to the spindles to make that connection adjustable (for that I need 2 nuts) and to add a large turnbuckle-like fitting in the center. I can then bend each half of the rod separately and align them perfectly. I'll have 4 potential adjustments so if I get close to the proper finished length I'll be able to adjust it accurately. For the turnbuckle I need 1 LH and 1 RH nut...so 4 in 3/4-16 and 4 in 7/8-18.

 

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I put the 3-jaw in the 4-jaw for this to grab 3 sides of the hex.

 

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The 3/4-16 nuts were easy but 7/8-18, the old SAE spark plug thread, isn't even in Machinery's Handbook so I had to calculate the hole size by looking up 7/8-16 and 7/8-10 and splitting the difference. I came up with a range of .820 to .825 and was going to have an cutter ground to that size when I remember I had a .825 counterbore. I can't even remember where I got it. It's not a conventional size and I'd never used it before but it was worth a try.

 

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It worked well - as well I could hope for.

 

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Tomorrow I'll make a couple of 7/8 holding fixtures to trim the nuts down and put a chamfer on them. I don't know when I'll get to finish the tie rod - probably not for a long time but I can put these in a box on the shelf until that comes about.

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Posted (edited)

You wouldn't think making some special nuts would take all day - but it has and I'm still not finished. I started out by trimming the threaded nuts down to size. For the 3/4 nuts I had some threaded rod to use to hold them - it's not as good as my fixtures but worked.

 

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The LH threaded nuts are a trick. To do it you run the lathe in reverse (easy with a 3-phase motor) and cut on the opposite side.

 

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After I trimmed the first one I thought they were too thick so I measured one of the originals. Sure enough, they really are 3/4" tall. Interestingly, because they were made as lock nuts they only have a chamfer on one side. The nut in the foreground is a conventional 3/4-16 - smaller in both height and measurement across the flats.

 

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With those done I made two 7/8-18 fixtures for LH and RH threads. This is a size you will never find threaded rod for – in fact, I've never seen this thread referred to except in the old SAE handbook and that was for spark plugs..

 

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I trimmed the 3 RH nuts and decided to call it a day.

 

Also - and this is very exciting – this arrived.

 

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This is the prototype for the Unterberg & Helme "snap starter" - the earliest type of impulse starter, patented around 1906. Some time ago I was looking into impulse starters and came across a reference to this invention. I found the patent drawing and description but, try as I would, I simply couldn't make sense of it. So, I sent the patent to Terry Harper. Terry has a background in industrial design and I though he might understand it. He took the patent and assigned it to his students as a project. They've been working on it and it looks as if they have solved the problems. I'm very impressed, especially as I think these are HS or JHS age students - not MIT graduates. I have yet to take it apart...and I'll have to figure out how to make the various components. I also have to think of a way to attach it to a Bosch magneto since, in the original design, it was permanently attached to the U&H magneto. I think I've got a solution to that problem. One very interesting feature is that this unit is engaged via a rod to the dash - so it only functions when you engage it, thereby avoiding the problem Layden Butler mentioned of impulse starters interfering with manual spark advance.

 

Edited by JV Puleo (see edit history)
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Joe,

 

I am so glad it arrived safely! Again thank you for allowing us the opportunity to work on such a challenging and interesting project! 

As I mentioned in the the letter, the model isn't perfect but it will explain how it all functions and give you a good base to work from. One issue I noticed is I think the case needs to be a bit longer and/or the slots the levers work in need to be larger - there wasn't enough room or play to get it to release. With the cover off I was able to get it to wind the spring and release and lock as its supposed to. 

 

Whenever I come across a clever design such as this I always wonder how they developed it and what the thought process was. I also always end up asking "Why didn't I think of that!" (LOL)

 

My student that worked on this project is a senior and in the Fall will be attending the University of Maine, College of Engineering for Mechanical engineering. He put a ton of work into it and is justly proud of his accomplishment. 

 

Again, thank you so much for the great opportunity and learning experience!

 

 

 

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Edited by Terry Harper (see edit history)
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This is by far the most interesting thread I follow. Always some new technic to solving a problem or something like this snap starter with help from others.

I look at the detailed drawing but can't figure how it works, I am sure will learn more about it. Thanks Joe & Friends!

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Thanks guys...

I've high hopes for your student, Terry. He's clearly shown real talent here. As to the process, it would not surprise me if they had the same issues making this the first time as we have in recreating it. If I've learned anything from all this it's that design is evolutionary - the final form is almost never the first and you have to make things - or try to make them - to arrive at the workable solution. I think it's the major difference between theoretical and practical engineering. And, at the risk of being accused of political talk, I think the practical aspects of design are being constantly slighted. The notion that you can design without being able to do just means someone else has to do it, find the faults, and make the corrections.

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Posted (edited)

I finished the nuts and then wasted half the day working on my 89 S10- Blazer. The tail gate wouldn't open - actually the &*() plastic lock cylinder that pulls in the locking rods must be stripped. I've been unable to get it open all winter and was waiting for better weather because I have to do that sort of thing outside. I did get it open - although the shop manual - which I bought when I got the truck - was worthless for that. Thankfully I didn't break anything and now I know what I need to get to really repair it. I hate plastic car parts!

 

With that out of the way I tidied the shop up a bit and started on my plan B radius rod ends by cutting two of the square pieces I'd made previously in half.

 

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Giving me 4 relatively equal pieces.

 

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Then set up the 4-jaw chuck to hold them and faced them off. This is a lot easier than doing it on the mill.

 

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I have to drill two more 5/8 holes in them so they all match but so far it's working.

 

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Edited by JV Puleo (see edit history)
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Joe.


To find the tap drill for any thread inch or metric just subtract the pitch from the diameter. Pitch = 1 / TPI. So for a 1/4 - 20, 1 divided by 20 = .050 So the drill size will be .250 - .050 = .200 For your 7/8-18 thread 1 divided 18 = .05555 So .875 -.0555 = .8195. This works with metric as well. 6mm x 1 is just 6 minus 1 = 5 mm.

Keep up the good work, Thanks for posting all your work.

Best,

Jim

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Posted (edited)

 

I like that...I'll print it out and put it in the tap drawer. oh...and I'm a southpaw too.

 

I drilled and reamed holes in the "blocks" for the radius rods this morning...

 

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I'm going to use threaded rod for this - I'd have to for the LH thread so I may as well make all the pieces match. I put each piece in the lathe to drill the threaded hole.

 

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And then tapped them...

 

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Actually, I start the thread in the lathe. to make sure it's straight,  and then over over to the vise on the mill and use a conventional tap wrench since it is so much easier.

 

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This is what I'm aiming for. The pieces of threaded rod will be permanently fixed in the ends. If it comes out as I plan, you won't even be able to tell how they were made.

 

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This would have been easier if I'd used 1" x 1-1/2" flat stock but I couldn't think of a way to center it in the lathe to put in the threaded hole. Also, I'm going to put a tapered pin through the block and the threaded rod and then surface grind the piece...as well as put a steel bushing in the bolt hole. In thinking about it, I should have used 1-1/4 x 1-1/2 and used the mill table to locate the threaded holes. This always happens - I get part way through the job and think of something better. Actually, I'm certain this is the process the original makers went through.

 

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I finished 1 surface . I'll do the others tomorrow. The RH threaded rod should come in tomorrow also so I can keep going with this.

 

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I'm not all that great at face milling but the finish came out really good this time. I think its the best I've ever done.

Edited by JV Puleo (see edit history)
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I decided to do these one at the time rather than two at a time because, with two, if the width's aren't perfectly matched one can be loose. This is cold drawn stock and it's very close to the dimension but, I disconvered, not

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