Jeff G 78 Posted May 9, 2012 Author Share #61 Posted May 9, 2012 (edited) Speaking of cost, I remember a point the CZOT guys made. They put a 1 1/2 hex head on the rod. The wrench was $100. Might be better to weld on a T'd pipe you can put a tire iron into instead of using a big socket or wrench.The 1-1/2" wrench would need to fit the nut, not the rod. I'm not sure you could get enough strength without distorting the nut if you welded long arms to it. They do sell large wing nuts, but only in 1"-6 pitch and they are expensive. I found jumbo wrench sets at Harbor Freight for about $45. They might also have them individually in the store??? I HATE Harbor Freight, but how bad can a giant box end wrench be? A large adjustable wrench could also be used.I priced everything needed for the puller at McMaster-Carr. For the standard thread tool, the rod, nut, and washer is $17 and some change. Add a 1" black steel nipple, a 1"x3/4" reducing coupling, and a 1" coupling and the total material cost would be around $25-$30. I am going to ask a friend to let me use his lathe to make the prototypes, so there should be no additional labor for my trial tools. The acme thread puller will be about $45-$50 total. I plan to use an old spare strut bearing, so that too is free for the trial puller. Once everything is proven-out, I would need to procure some sort of thrust bearing for those who don't have a stash of spare Z parts laying around. I only have a few bearings handy, but I might have more somewhere in storage.I did check the specs on the 1"x3/4" reducing coupling and the 3/4" long machined area of the rod should work fine. The coupling is only .55" long for the small end.What am I missing???EDIT: McMaster has a thrust bearing for about $20. Ideally this would only be needed for those who couldn't find a free strut bearing. Edited May 9, 2012 by Jeff G 78 Link to comment Share on other sites More sharing options...
Captain Obvious Posted May 9, 2012 Share #62 Posted May 9, 2012 (edited) Nice sketch! What are you missing? It's going to be extremely difficult to machine that rod if it's already hardened. You could grind the OD down to 0.75, but putting in those internal threads is going to be a royal b*tch.Other than that, I don't see anything obvious.Is the 1" black iron pipe intended to slip over the threaded are? I'm just wondering if the internal weld bead in the pipe is going to cause problems.Also, I doubt thrust washers are going to be rated for the load you intend. If your pins are like the ones I've messed with, you're going to be putting a lot of force on it. A whole lot.What's the dimension of your typical 1x14 hex nut? Might not be as big as 1 1/2. I think you'd have to buy a whole wrench set at Horror Fright... You can buy singles elsewhere, but you'd pay as much for one quality wrench as you would for the entire set of HF junk. Edited May 9, 2012 by Captain Obvious Link to comment Share on other sites More sharing options...
Jeff G 78 Posted May 9, 2012 Author Share #63 Posted May 9, 2012 (edited) Nice sketch! What are you missing? It's going to be extremely difficult to machine that rod if it's already hardened. You could grind the OD down to 0.75, but putting in those internal threads is going to be a royal b*tch.Other than that, I don't see anything obvious. Is the 1" black iron pipe intended to slip over the threaded are? I'm just wondering if the internal weld bead in the pipe is going to cause problems. Also, I doubt thrust washers are going to be rated for the load you intend. If your pins are like the ones I've messed with, you're going to be putting a lot of force on it. A whole lot. What's the dimension of your typical 1x14 hex nut? Might not be as big as 1 1/2. I think you'd have to buy a whole wrench set at Horror Fright... You can buy singles elsewhere, but you'd pay as much for one quality wrench as you would for the entire set of HF junk. I'll ask my buddy at work how hard it would be to drill and tap the rod. He does a ton of machining, so he'll know. After looking at the pipe fittings again, I *might* be able to keep the rod a full 1" diameter and grind a flat into the 1" pipe coupler to clear the LCA flange. The 1" coupler has an O.D of 1.77" and the LCA flange can handle 1.5", so it might just work without adding extra machining to the rod. I'll buy a coupler and experiment before I turn the rod down to 3/4". Yes, the 1" iron pipe will slip over the 1" all-thread. I have tried it with 3/4" rod in a 3/4" pipe and it fits fine. I will not be using thrust washers. I will be using a thrust bearing. The Z bearing holds up the corner of the car, so it should work fine. I agree that a thrust washer would not work nearly as well. All 1" hex nuts are 1-1/2" across the flats from what I can tell, so yes, I'd need a 1-1/2" box end wrench of a big adjustable wrench. I'll check around and see what I can find. I really don't like giving HF any of my money. EDIT: I just rechecked and the acme hex nut is actually 1-5/8" across the flats. I guess I might need the jumbo wrench set after all since the standard threaded nut is a 1-1/2". I just looked at the dimensions of another type of coupling and it is only 1.58" O.D which might just fit under the LCA flange. I think we solved the issue and the rod will no longer need to be machined down to 3/4". Edited May 9, 2012 by Jeff G 78 added info Link to comment Share on other sites More sharing options...
beandip Posted May 9, 2012 Share #64 Posted May 9, 2012 Jeff, for several years I was loaning these tools to Z drivers here on this web site. In fact I sent the drawings to Zhome and they have them on the site for down load. The first pullers were made of harden all thread but were not large enough . 3/4 Acme all thread offered at a machine supply is what you need. Especially if it is for repeated use. When you attach the adapter to the all thread do not weld it in place. This way this can easily be replaced. Always run a Die over the 12mm pin first. The outer shell that houses the all thread is only 1'' gas pipe with a large washer welded to one end so the all thread can stick out. Use a thrust bearing there and another washer and harden nut . If you build one with this materials it will work great. I have gone through several puller over the past 10+ years of sending them all over the USA to at least 80 owners. There have been a few tool failures but as the design was improved along the way this final design. is ''Bullet proof . I did not build these things just loaned them out. Another member here was the maker . He was lending them to members on hybredZ for a while. My last puller finely wore out and I can no longer get parts so I had to discontinue . By the way, using the puller you can save the old pin and reuse them. Gary Link to comment Share on other sites More sharing options...
Captain Obvious Posted May 10, 2012 Share #65 Posted May 10, 2012 Cool. Sounds like a plan! Your machinist buddy should ask "Well, how hard?" You should have the hardness numbers handy when you talk to him. In general, "Hardened" means "Must resort to grinding - Cannot be cut with conventional means".When you get a chance, snap a pic of the coupler and pipe options that you've got laid out. Would help with the visualization. (For me, at least. :stupid:)Another idea? You could maybe pick up a relatively long 1" diameter bolt at a big box store for a dollar or two and lop off the head for proof of concept? Link to comment Share on other sites More sharing options...
Jeff G 78 Posted May 10, 2012 Author Share #66 Posted May 10, 2012 I asked my friend and he said that 4142 machines fairly well with lots of cutting oil.I'll post some links to the couplers in a bit. I'm playing with Autocad right now. Link to comment Share on other sites More sharing options...
Captain Obvious Posted May 10, 2012 Share #67 Posted May 10, 2012 I asked my friend and he said that 4142 machines fairly well with lots of cutting oil.Are you buying it annealed or already hardened? If it's annealed, then yeah, it's a breeze to machine. But of course, it won't be hardened. If it's already hardened, then machining is more difficult. I guess once you punch through the case hardening, it should be softer inside, but then again... so will the threads. I'm no expert in the field... Just thinking out loud.Was this something from McMaster? I took a quick look over there and didn't see anything that clearly stood out. Everything was too long, and the best stuff they had was grade 8 and it cost more than what you listed above. Link to comment Share on other sites More sharing options...
Jeff G 78 Posted May 10, 2012 Author Share #68 Posted May 10, 2012 (edited) Hey Cap'n. If you go to McMaster and search "acme" you will see the threaded rods. The one I chose is the alloy ASTM A193 Grade B7 which is a chromoly 4140 quenched and tempered to a 4142. So yes, it is hardened and yes, it can still be machined. For now, I will buy just a 1"-10 x 12" rod as well as the same thing in a standard thread 1"-14 x 12" which is the same material spec as the acme rod.It certainly won't machine like a low carbon steel rod, but my buddy says it will do fine. Edited May 10, 2012 by Jeff G 78 Link to comment Share on other sites More sharing options...
Jeff G 78 Posted May 10, 2012 Author Share #69 Posted May 10, 2012 OKAY, This drawing is a wee bit better. It's NOT a proper drawing since I decide to mix sections and plan view for clarity. Let me know if you have any suggestions on my drafting techniques. It's been a LONG time since I last did a proper drawing. I did the drawing in AutoCAD 2000 (old school), printed it and scanned it as a picture. If anybody wants the CAD file, let me know. Link to comment Share on other sites More sharing options...
Captain Obvious Posted May 10, 2012 Share #70 Posted May 10, 2012 If I found the right stuff, it has a max hardness of C35, so it shouldn't be a problem to machine. Yesterday I was thinking it could be an issue since the little poking around I did turned up that the chromoly stuff can be case hardened all the way up to like C60 or so, and that could be a problem. I'll be the first to admit that I'm pretty far out of my element with the metallurgy stuff. I know just enough to be dangerous. I'm just asking questions poking around trying to help out by looking for holes. The overall drawing makes perfect sense to me, and one suggestion would be to include some feature to be able to turn the threaded rod by itself. Maybe a set of flats out on the non-business end or a cross drilled through hole for a rod or something like that? I'm thinking to help thread the rod onto the spindle, or remove it from the spindle when you're done? Maybe in some rare situation the spindle pin could turn as you're trying to pull it? You could use two large nuts as jam nuts in most situations, but I'm thinking something more elegant. Not sure you would ever really need it, but maybe? Boy, I would have loved to try this thing on the last pin I pulled. I don't know if it would have worked, but sure better than what I ended up with. Link to comment Share on other sites More sharing options...
mgood Posted May 10, 2012 Share #71 Posted May 10, 2012 Just drill a 1/4" hole 1 1/2" from the left end, then you can use a screw driver to help turn the all thread. Link to comment Share on other sites More sharing options...
GreenZZZ Posted May 10, 2012 Share #72 Posted May 10, 2012 Awesome Jeff! I'll try to pull the CZOT guys into the discussion for their input. Link to comment Share on other sites More sharing options...
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