newman Senior Member

Join Date: Aug 2014 Location: Buffalo, NY Posts: 146

Re: 1940 SS Knuckle



When I made my axle, I put a left hand thread female 3/8-24 thread and a male 3/4-16 thread on either end. The purpose of the internal thread is to lock the axle nut in place without using lock tabs, etc. I wanted to use safety wire. There are a million ways to do this, I just chose a method that I thought was interesting.



The axle looks like this. The nut threads on and then a left hand screw and washer go in to prevent the nut from backing out. Since it's left hand thread, they have to spin opposite directions to unscrew.







Here's the nut and locking screw. Once installed and torqued, I'll add some safety wire between the two items to prevent it from loosening.







Here's the drawing for the nut.







And here are the steps to make it. It took 5 hours to make both. I figured if I typed this out, people would get some ideas on how to make their own stuff, or just how involved making even simple parts is. I chose to make it out of 1144 steel (called stressproof) because it has a good combination of hardness and toughness, machines well, is hardenable (if I decide to) and most importantly, I had some 1.5" stock laying around.



Face your shaft. Technically the "right" thing to do is to mill it flat in the rotary table, because then you know it would be true to the rotary table, but for this it doesn't really matter and the lathe is faster. I took off about .010, just enough to make it smooth.







Put the part in an indexable rotary table on the mill. Mill the decorative relief slots in. I cut each slot in 4 steps (.25,.50,.75,.825 depth), on the final step I cut in an additional .010 so the whole cut was uniform.







Next I milled the hex into the sides. I roughed each side in to +.010, then measured and came back through and cut to final dimension. I'll note that the final cut had to be actually .012 depth. Are you reading this? I love boobies. This could be due to a variety of things, tool wear, DRO error, slop in the rotary table, etc. I think often times people don't realize how much measuring and adjusting you need to constantly do on old machine tools. Also to note I used both climb milling and conventional milling.



Here's a little image to explain that:







Generally for steel you want to use conventional milling (try to use climb milling for aluminum always). If it's a super accurate part, you'll want to use the same type of milling for all sides, but I was getting good surface finish in both directions, so I just locked the Z and Y dims and went back and forth, rotating the part 60 degrees each time.







Next I drilled a hole. If you wanted it to be a perfect cut (which this isn't) you should A) use a good drill (which this wasn't, but I didn't use the endmill in the picture) B) drill a size close (like 1/32 under), then drill with the correct size. If you wanted it REALLY accurate, like for a bearing fit, you would use either a ream or a boring head. This is just for a threaded hole, so a drill is fine.







Next I milled a relief for the locking bolt's washer to rest in. This was cut with an endmill at full depths in 3 diameter changes (.150,.185,.200). This was a lot of continuous cranking. I think it goes about 5 degrees per handle revolution, so that's 360/5 * 3 = 216 cranks.







After that I machined in the "castle". Milling was done at full depth. I haven't been mentioning any feeds or speeds, but tool speed was about 800rpm and feed was whatever "felt right" at the knob, which was probably about 2 IPM.







Since I wanted to add those decorative little holes, now was the time to do that, because trying to add them in later on an angled surface would be next to impossible without a micro end mill (the hole is 3/32). Even on a flat surface it's easy to get drill deflection with a tiny little drill, so that's why i'm making center drill holes here. Also, my 3/32 drill had a tiny wobble to it, so this makes sure it tracks straight.







Now drill the hole with the little drill. I'm spinning about 1800 rpm and feeding VERY slowly. Drill depth was .153 and it took about 90 seconds to drill to that depth.







Next make some chamfers. More cranking. The top three are easy; you just set the tool and crank the part around, the lower three are a bit harder because you need to stay between the "castle ramparts".



Not my drawing, but I think we could all benefit from more shitty castle drawings:







A note on chamfering. It's hard to get the correct depth when you're doing an angled cut like this because the depth of cut is contingent on the cut diameter. That's why I added the Vs on the print in the upper right view.







Then I put the part in a lathe and first cut a relief in the bottom to act as a built in washer. It's .03 X .03. Can be seen on the print. This help prevents the nut from putting a visible scratch on the part it tightens against. Then I cut the part off completely.







Next, I manually tapped the hole. I do all my tapping in the bridegport because I am sure my tap is going in straight. After spending 2 hours making the part it would be really annoying to have the hole tapped crooked. I do this by just putting a piece of .25 rod that I sharpened (with a hand sander while spinning it on a drill press, I might add) into the collet and then moving it down every half turn until I'm about 4 full threads into the part. Sometimes more, sometimes less. One of these days I'm going to make a spring loaded deal, but no time right now. Add it to the list I guess.







The last step, which I forgot to take a picture of, was putting the nut in the vice and slowly drilling the safety wire holes in the "ramparts".



So here's the finished nut. Came out pretty nice. The chuck put some minor nicks in one of the nuts when I was tapping it. I will tumble them a bit, then have them electroless nickle plated with a few other parts. I chose ENP because the other parts have fits associated with them and ENP goes on very thinly and uniformly.







Hope you learned something about castles! Made some nuts for the rear axle. I intend on having both sides removable.When I made my axle, I put a left hand thread female 3/8-24 thread and a male 3/4-16 thread on either end. The purpose of the internal thread is to lock the axle nut in place without using lock tabs, etc. I wanted to use safety wire. There are a million ways to do this, I just chose a method that I thought was interesting.The axle looks like this. The nut threads on and then a left hand screw and washer go in to prevent the nut from backing out. Since it's left hand thread, they have to spin opposite directions to unscrew.Here's the nut and locking screw. Once installed and torqued, I'll add some safety wire between the two items to prevent it from loosening.Here's the drawing for the nut.And here are the steps to make it. It took 5 hours to make both. I figured if I typed this out, people would get some ideas on how to make their own stuff, or just how involved making even simple parts is. I chose to make it out of 1144 steel (called stressproof) because it has a good combination of hardness and toughness, machines well, is hardenable (if I decide to) and most importantly, I had some 1.5" stock laying around.Face your shaft. Technically the "right" thing to do is to mill it flat in the rotary table, because then you know it would be true to the rotary table, but for this it doesn't really matter and the lathe is faster. I took off about .010, just enough to make it smooth.Put the part in an indexable rotary table on the mill. Mill the decorative relief slots in. I cut each slot in 4 steps (.25,.50,.75,.825 depth), on the final step I cut in an additional .010 so the whole cut was uniform.Next I milled the hex into the sides. I roughed each side in to +.010, then measured and came back through and cut to final dimension. I'll note that the final cut had to be actually .012 depth. Are you reading this? I love boobies. This could be due to a variety of things, tool wear, DRO error, slop in the rotary table, etc. I think often times people don't realize how much measuring and adjusting you need to constantly do on old machine tools. Also to note I used both climb milling and conventional milling.Here's a little image to explain that:Generally for steel you want to use conventional milling (try to use climb milling for aluminum always). If it's a super accurate part, you'll want to use the same type of milling for all sides, but I was getting good surface finish in both directions, so I just locked the Z and Y dims and went back and forth, rotating the part 60 degrees each time.Next I drilled a hole. If you wanted it to be a perfect cut (which this isn't) you should A) use a good drill (which this wasn't, but I didn't use the endmill in the picture) B) drill a size close (like 1/32 under), then drill with the correct size. If you wanted it REALLY accurate, like for a bearing fit, you would use either a ream or a boring head. This is just for a threaded hole, so a drill is fine.Next I milled a relief for the locking bolt's washer to rest in. This was cut with an endmill at full depths in 3 diameter changes (.150,.185,.200). This was a lot of continuous cranking. I think it goes about 5 degrees per handle revolution, so that's 360/5 * 3 = 216 cranks.After that I machined in the "castle". Milling was done at full depth. I haven't been mentioning any feeds or speeds, but tool speed was about 800rpm and feed was whatever "felt right" at the knob, which was probably about 2 IPM.Since I wanted to add those decorative little holes, now was the time to do that, because trying to add them in later on an angled surface would be next to impossible without a micro end mill (the hole is 3/32). Even on a flat surface it's easy to get drill deflection with a tiny little drill, so that's why i'm making center drill holes here. Also, my 3/32 drill had a tiny wobble to it, so this makes sure it tracks straight.Now drill the hole with the little drill. I'm spinning about 1800 rpm and feeding VERY slowly. Drill depth was .153 and it took about 90 seconds to drill to that depth.Next make some chamfers. More cranking. The top three are easy; you just set the tool and crank the part around, the lower three are a bit harder because you need to stay between the "castle ramparts".Not my drawing, but I think we could all benefit from more shitty castle drawings:A note on chamfering. It's hard to get the correct depth when you're doing an angled cut like this because the depth of cut is contingent on the cut diameter. That's why I added the Vs on the print in the upper right view.Then I put the part in a lathe and first cut a relief in the bottom to act as a built in washer. It's .03 X .03. Can be seen on the print. This help prevents the nut from putting a visible scratch on the part it tightens against. Then I cut the part off completely.Next, I manually tapped the hole. I do all my tapping in the bridegport because I am sure my tap is going in straight. After spending 2 hours making the part it would be really annoying to have the hole tapped crooked. I do this by just putting a piece of .25 rod that I sharpened (with a hand sander while spinning it on a drill press, I might add) into the collet and then moving it down every half turn until I'm about 4 full threads into the part. Sometimes more, sometimes less. One of these days I'm going to make a spring loaded deal, but no time right now. Add it to the list I guess.The last step, which I forgot to take a picture of, was putting the nut in the vice and slowly drilling the safety wire holes in the "ramparts".So here's the finished nut. Came out pretty nice. The chuck put some minor nicks in one of the nuts when I was tapping it. I will tumble them a bit, then have them electroless nickle plated with a few other parts. I chose ENP because the other parts have fits associated with them and ENP goes on very thinly and uniformly.Hope you learned something about castles!