Making a BIG Nut for Hydraulic Cylinder | Machining & Milling

how you going guys Kurtis from Cutting Edge engineering today's job we're going to be machining up the new nut for our EX1200 cylinder rod and re-threading the rod to suit our new nut so if you missed part one we had to gouge the seized nut off the rod we'll leave a link in the description below so our material has arrived and so has our upgraded tooling from our supplier so our piece of material is a piece of 4140 centerless ground rod it is eight inches in diameter and 150 mil tall I did try to buy this in a hollow bar to save a little bit of work but the sizing I needed is not available so we're just going to have to start with a piece of solid bar and at the moment this piece of material weighs 38.4 kilo we have got a lot of work to do with boring it out and turning the OD so it will be interesting to see what we're left with first thing I'm going to do is get it set up in the lathe so the first thing I'm going to work on is the ID of the nut so I need to drill and bore it to size but before I can do that I'm going to face the end of the material and put a center in it so I can start the drill so what I need to do now is drill a hole through the piece of the material and to do that we're going to be using some of our upgraded tooling so let's show you what we got so what we got was two new boring bars to do internal threading and we also got our new drill which I'm very excited to use that goes with this so what I ended up getting was a 90 mil Spade drill it is a bpk brand made in Korea what makes up the drill are four parts there is a drill body there is a collar there is then the drill head and the insert so one of the reasons why I decided to upgrade to a spade style drill is with this drill body and this head I have got a range from 90 to 101 mil but not only that the inserts you can buy they can go up in size in point one of a mil increments so you can drill over a hundred different size holes with this one drill body and head another great feature of these drills is you can buy extensions that you can bolt onto the body to then make the drill as long as you want another one of the reasons why I've gone to a spade drill is I have got many different sizes of very large diameter twist drills they are all secondhand to me I've never bought any of them new and after time after they get re-ground they do lose their hardness and they're just not keeping an edge and for the price of two twist drills about 75 mil in diameter was actually dearer than me buying this entire setup providing I don't damage the drill head or the body all I need to do is replace the insert and you may have seen me using Kruz drills they are fantastic for drilling induction hardened material and you can get different geometry drilling inserts for them for doing different sorts of jobs but the Kruz drills only come at what size you buy you cannot put a larger insert in them we have been thinking about doing a comparison video of the three different styles of drills it's not something that we would normally do so if there's enough interest in it we'll make a video so let us know in the comments below so because we are moving over to insert drills they do require through coolant otherwise you do burn out the tips and it does get very expensive I have been using a morse taper to ER50 collet chuck in order to use my Kruz drills but that's just not going to work long term so I've also upgraded a holder that goes in the tail stock so I can feed coolant through the drills I've been looking for one like this for quite a while I didn't find anything that I was willing to invest in so I did put my tooling supplier on the hunt to try and find me what I wanted he did find this in Taiwan at a company called Precise so a lady Miss Sherry helped him out and they got me the holder that I wanted thanks Miss Sherry and Arthur from live tools so what we got was the morse taper five side lock holder that you can feed coolant down through your drills this one has reduction sleeves so you can put different size side lock drills into it without having five different holders it'll be interesting to see how this performs and something else I did do I did put a manifold up on the coolant system so I could feed coolant through a flexible hose down through the drills doing that would mean the hose has flexibility and it would move with the tool but that's not really working to plan I believe because I'm using air fittings they are quite restrictive so I'm just going to have to change that later on but just for now we're just going to use a lock line straight into the top of the drill righto so pretty happy with those results that only took about 12 minutes to punch a 90 mil hole through a 150 mil thick of 4140 so the surface finish in there is actually really good it's very smooth and it's not scratched it was a little bit chattery and a lot of vibration in the beginning trying to get the insert into the job but after it was in there it just ate it after using the drill a little bit more I would probably be able to dial in the speed and the feed rates in order to maybe make it a little bit better I was being a little bit conservative because I don't want to damage it and it is the first time I've used it so very happy with that now that we've successfully drilled that to 90 mil we're going to bore it out to its finished ID so I've got the ID bored to size I'm just going to skim the OD down to our final dimension then I have a step to machine into this end of the nut and that is what's going to go underneath the piston and then we can thread it so now it's time to do the threading we're going to be using one of our new boring bars so I ended up getting two bars the same diameter and the same length these are 40 mil in diameter 300 mil long one is more suited for finer thread pitchers | and I'll be using a three mil full form insert hmm so I'm starting to run into a little bit of chatter as I'm getting to the final dimensions of the thread what I'm going to do is slow down the RPM and take some spring passes just to try and eliminate that chatter so that thread looks really good in there we're perfectly on size so I'm not going to go any further with it what I'm going to do is flip it in the machine so I can start doing the other side now that it's slipped all I need to do is turn the OD to size face it to length and machine in a relief in the bottom of the nut matched in spot on righto guys so I've got all the turning done on the nut what we're going to do now is take it out of the lathe and go set it up in the milling machine righto so I've got it set up in the milling machine now what I'm going to do is mill six equal sides on the nut and that is so the spanner that goes on the ram bench that torques the nut up to the required spec will fit over the nut to do that we're going to be using a super indexer it has a six position plate in the back of it so I can turn it six times equally and get a perfect hexagon so I'm gonna mill each edge to within half a mil of its finished size once I've got all the material roughed out I'm then going to come in with a fly cutter just to clean up the surfaces so those surfaces cleaned up really nicely there's just one more thing that I need to do and that is drill and tap a hole through the side of one of those flat surfaces and that will be for an M20 grub screw which will be used to lock the nut from undoing itself righto guys so that is our nut100 percent completed I'm really happy with how that came out everything looks really good and after all of the machining we actually removed half of the weight from what we started with it is now 16.2 kilo now that the nut's done we're going to get the rod set back up in the lathe so there were some common questions from viewers in the last video we thought we would answer the reason I gouged the nut off the rod and not machine it off in the lathe is the piston was actually covering about eight to ten mil of the nut so being able to get underneath the piston to completely machine it out would have been quite difficult gouging off the nut only took about 40 minutes and that includes setting up the gouger and doing the job setting it up in a machine to do that could take a couple of hours so gouging was by far the fastest method probably the most common question was why don't I just machine off the damaged thread put a new layer of weld on there and machine it back to size that is something you could do but there are a few reasons why I wouldn't do it there is no repair procedure or salvage procedure to do that to a cylinder rod because the material you are putting back on the rod is nowhere near the same tensile as the parent material even if you did get it to match up it would still need to be heat treated to avoid the heat affected zone which could potentially lead to hard spots and cracking even though we weld eyes onto cylinder rods it is a completely different application and under very different stresses and there are other workshops and people that will do a weld repair on a threaded area of a cylinder rod I have seen far too many of those come through my workshop that have failed it's either completely stripped the thread off the rod or the nut has seized onto the rod because they used material that was too soft to handle the torque being applied to it so even though that may be an option I'm not going to risk the customers very expensive rod because if that thread is to fail it is going to destroy another three thousand dollar nut and potentially the rod and that would be at my cost and as I said in the first video these components are a very high turnover item because of the environment they work in they are easily damaged so I'm not at all concerned that it has a custom nut on it or a custom thread on the rod because it probably won't be too long and this will be back here having a new rod put on it yeah I do need to remove that one a little bit more take this very steady righto guys so that's this job successfully completed we saved the cylinder rod for our customer and the entire job only came in at about half the price of a genuine Hitachi nut so we're gonna get this one on its way back to our customer although I'm probably going to see it again in a couple of months time for me to do a re-road on this thanks for watching for our ex 1200 Rod oh [ __ ] yeah right [ __ ] start again right so as I said in the first video oh [ __ ] oh [ __ ] me [ __ ] me ugh [ __ ] it has to be said in a way [Karen] not that way right you ready yep so our ugghh [giggle] so our material has arrived and so is how up [sigh] so our material has arrived and so is how ugggh [Karen] WHAT THE righto guys so that's this [ __ ] me righto guys ugghhh [ __ ] this sounds worse every time the more I say it it sounds like gibberish [Karen] that's because it is [Laughter] blugh blublublub [Laughter] English goOOod [giggle] me speak the good England [Laughter] thanks for watching [Karen] [Laughter] now what I'm gonna take it out with the forklift now thought I'd do something different ahhh ooohh yeaaah Mentos [Karen] OH look look look oh there's more mentos in there YEAH [Karen] is it gonna be a pink one come on pink one ah [ __ ] ahhh pink one mmm YAY throw overs are one of those things you're gonna get when it comes to 4140 and light cuts it's very difficult to get that even everything happy if you're a machinist and say you've never had one you're full of [ __ ] let me just get my ruler [Karen] [Laughter] that's so silly huh you're silly you silly duffer you silly billy [giggle] [whinging staffy noises] calm calm nah nah it's all right it's all right it's all right the day's finished we get to go home

Channel: Cutting Edge Engineering Australia

Views: 161,834

Keywords: cutting edge engineering australia, machinist in australia, machininst, abom79, cee australia, machining, Making a BIG Nut for Hydraulic Cylinder, making a big nut, making a nut, Hitachi EX1200, EX1200 excavator, mining excavator, hitachi ex1200 mining excavator, machining a big cylinder rod, hydraulic cylinder fail, cylinder rod repair, cylinder rod, making a cylinder nut, cutting internal thread on lathe, cutting external thread, super indexer, making a huge hexagonal nut

Id: zvKG5dgUHNw

Length: 45min 39sec (2739 seconds)

Published: Fri Jun 30 2023