Shoptalk 22 - June 2020

welcome back today we have another mixed bag off the shoptalk for you and as usual topics are all over the place I have a little bit on 5c backstop the repeatability of telescoping gauges not necessarily the precision off of task of engages just looking at the real repeatability and finally I talked about the bulky fix to post and why I chose it for my late for my life most of you might be familiar with depth stop that go into a 5c collet 5c collet has an internal thread on the end here and you can take a depth stop it screws in the back those are available commercially from different sources you can get them from harding for example or you can buy a Far East import which this one was screws in and gives you positive registration for your part to get kind of the same length of the parts in reality you don't because these are not dead lengths call us and depending on the diamond tolerance your your pole distance changes but for a medium accuracy work they are fine also they support the work against cutting pressure if you cannot clamp part very tightly for some reason the collet stop I have here started out in $7.99 special from Far East worked fine I turned down the end so I can go in a smaller call it but the annoying part was the threaded section here this is threaded relatively fine and the idea of to stop here was ready to sew to adjust it you had to just spin this about two-and-a-half thousand times to get at the end to end so that was no good so I took the original body after after depth stop and then I took a shaft collar to this is an off-the-shelf shaft collar obviously a larger one and i relieved one side of the shaft collar and silver brace the other side on on the backside of the the collet stop and this gives me a clamping situation with with one screw that's very very strong very quick to adjust so adjust it wherever you want and lock it and that doesn't move anywhere and the way I I lined everything up this is a twelve millimeter pin and this started out as a ten millimeter shaft collar a silver brace it on i roughly aligned it with the old screw that's the reason why the end of the screws turned down I had this in here screwed in and the shaft collar clamped on here then I spot welded it with the TIG welder in three places and then a silver silver soldered in the half of the ring on here that's why the other side is released so the side of the ring still can move while this is fixed to the body here then I just put it in lathe filled the slot with shrimp stock clamped it board and dreamed it to 12 millimeters so I can use case hardened and ground linear shafting like this piece here as a depth stop usually I would use it like this just a flat face or if I need if I want to support for example a large disc for grilling what I obviously did here because I drilled through into this this screw down this gear this sacrificial made a bunch of them at one this just screws onto the end of the shaft piece here and this allows good support and also sacrificial surface so this works very very nicely I'm quite happy that I finally did this after about five years goes on and you're good to go this unscrews from the end just just a single countersunk screw or a long screw and I drilled a little bit in the end here this is an m4 thread so I can also screw in thinner pilot diameters so if I have you just stopped for three or four millimeter call it I can machine a matching insert that screws in here very useful a small modification to a very inexpensive piece and works just fine so here is to stop in use I placed it beforehand about four millimeters behind the face of the of the kaulitz here and a part I'm going to face is will be 5 millimeter and then I took a boring bar a CC empty boring bar still insert that took a very very minor facing pass on the back stop that takes out any axial or radial run-out which translate and have an official run out because the face is wobbling it's not crazy bad it's about 0.02 millimeters of facial run out but we can do better than that and then I just drop my part in clamp it it's basically like a normal backstop for a 5c collet Chuck just more convenient because it's quick adjustable and you don't have to shred it a million times to move it this far the face is flat the other end will be drilled and tapped so I can insert smaller diameter or bigger diameter disks as a stop also drew hollow drilled one so so the the nipple from parting of a part can go in there and here we go four nine nine let's turn it 90 degrees four nine nine four nine eight four nine nine so that's pretty darn good five millimeter stainless discs I need to part off about 30 to 40 of these short pieces of five millimeter aluminium stock and I want to part them off very close to final lengths have a call it stopped in this 5c collet here and I want to run this talk like this just parted off take the part out push the stock up in up against the Collatz stop and be quite quite fast that way so this is of course that this is not a good condition you cannot run this at a thousand rpm and it be safe this would create a whipping situation and hit you in the forehead probably or as I heard on the with intolerance podcast you can't do that it's an illegal operation listen listen to the pup listen to that within tolerance podcast it's really cool it's really fun lots of great guests there one of the recent one was tumblr so what I do instead this Robin shut this years ago take a brass tube as a liner as a guide row for DES for the stock this goes in the tail stock for my life okay and now the five millimeter rod is guided relatively safe so it's goes on the chuck up against the stop tighten it down running at 2,000 rpm I'm going a little bit past past the center with the parting tool to cut off the lip right away the departing tit work goes out stock comes up a spindle liner begins to stop [Music] [Music] once I'm almost screwed material you see me putting some drag on the stock and this usually breaks off the the remaining material reasonably flat on the end of the stock Reeboks Robin talked about the issue with them in one of his videos really and that's the deflection of the part by the clamping screw when you use a V block for work holding like this on a grinder or on a mill or whatever or you have a V block on a spin fixture on your surface grinder or tool grinder and you use a single screw as usual in the center and you clamp down like this there is a large likelihood that the part is going to deform and deflect and what's happening there is the screws pressing down on on your part and due to the force it gets in the area of the screw wedged down further into the V block because it's very high load and it's still resting out here where it was before that means that your that the part goes into a banana shape it bows like this and Robin talked about using a spreader piece up here too to meet me negate that effect but I want to visualize that effect so let's bring in a dial indicator this is a 2 micron per division dial indicator the indicator is resting on top of the of this ground style pin and when anil goes right that means that part is lifting and when the needle goes left that means the part is dropping and when I tighten this stamping screw now across pin and two fingers watch what happens on the indicator nothing so we're very close to the Vblock very close to the resting points out here and there the effect is very minimal but when we move out like an additional 40 millimeters like this now we are about 40 millimeters a wave one from the V block and when I tighten the V block screw again group part move it bends obviously it goes up by about 10 10 microns that's point O one millimeter that's a a little bit less than half a thousandth of an inch now I have a spreader bar in here that is reasonably high so it's reasonably stiff in vertical direction surrett out the indicator are close to just watch the needle move or not move and I'm tightening again with roughly the same torque as before and it still moves a little bit but it's more in the 2 to 4 micron and I just bumped the the magnetic stand but as you can see the spreader piece changes the behavior by a great amount I get a deflection of maybe 2 micron now out here on the end compared to 10 to 20 micron without the spreader piece and the spreader piece is really just a piece of flat stock you can make a fancy one with a small move with a wee groove down here and a small dimple up here so the center on the screw head but usually I'm just too lazy to make something like that so and here again without the spreader piece yeah for precision work that's not good that's really bad in this case this is now 16 microns off-center that's that's a that's a lot that would relate to a total indicated run out of something like 38 microns and that's a hell of a lot especially if you're doing grinding work so I just want to add this to Robyn's video where he showed this just to visualize the effect and just make you think about strain contact pressure of a screw what happens when you tighten a screw things like that I want you to do a blind test with telescoping gauges I use this quite a lot because I found that they give me good results but I'm working on some relatively precise parts now I want to do a blind test usually I look at the micrometer display while I'm reading or feeling the telescoping gauge so and this time I want to do 10 measurements blind take the tape off take a reading write it down and then calculate the average and see how much I get deviation and I will take ten individual measurements on the part and check them with the micrometer okay first one I'm at the upper limit of this micrometer okay that's my first reading that's 26 point 503 now the closer display back up and we gift the spin and we take a new measurement and when I take a measurement on the on the telescoping gauge I like to start small with the with the micrometer open up mitt up slowly and when it starts when the telescoping gauge starts to engage into the micrometer between the two handles I will slowly open it up more and I will constantly change the orientation of the of the task of engage and slowly open up and at some point the telescoping gauge will slip between the anvils and no matter the orientation I will not get any resistance then I will slowly move the anvil back in a little bit okay and then I get resistance and then I move it back there is and then I find a very very small amount of resistance okay that's good twenty-six point 501 open the last cup engage moved the micrometer take another measurement and I won't do this until I get ten measurements okay and the way I like to use two telescoping gauges as pretty much standard whatever buddy does I think I like to compress them so you get them in clamp them you go in the bore release the spring tension then I wiggled them first of all up and down and that way they kind of self-centering the bore then I I go a little bit off axis with the handle of the telescoping gauge then I lock it a little bit how much you tighten just depends on your telescoping gauge you have to try it if you tighten this to lose the the plungers will creep out after the measurement if you tighten this too hard your dimensions will come out oversized because deflection when you sweep the bore diameter then I just do a single sweep out usually at the way out I give a little bit more drag on the screw here there is no real magic to these there are a few points you have to you have to get used to them especially to set your using the most you have to practice I asked with every skill based tool you have to practice a little bit at least take a gait ring or something you know the diameter a bearing race in a race something like that and just do measurements over and over and over and over and also do blind tests by covering the dial or the display of air micrometer who a rough measurement that would even use something like calipers this usually gives me a good got ballpark dimension of the bore these are meter Toyo telescoping gauges they're a little bit nicer than the 15 euro or $15 sets that you can get on Amazon but even those work if you do some work to them missile Tony did a video on them we showed the internals and what to do to make them a little bit nicer so that's my next measurement 26 point 501 well I I see a pattern here already you okay twenty six point four nine six the problem with telescoping gauges is they require the necessary skill to pull off a decent measurement with them something like a three-point internal mic doesn't need much skill you need some training to do it properly but once you know how to use them they are skill independent not so much with the telescoping gauges they are telescoping gauge I would consider high skill high risk twenty six point four nine eight yeah okay let's look at the numbers but just looking at the numbers well it's definitely twenty six and it's definitely in the point four point six range let's try calculating the average divided by ten and this gives us an average of twenty six point five three that's most likely completely off because when we look at the numbers and we would do a put this in the graph we would have like I'd say we let's make a graph these are the measurements 1 to 10 10 measurements and we have twenty six point five twenty six point six twenty six point seven so twenty six point six twenty point five sorry twenty six point five twenty six point five twenty twenty six point six seven that's almost twenty six point seven twenty six point five twenty six point five twenty six point five and a little bit twenty six point five twenty six point five and twenty six point six so it looks like most likely this and this is an offer is an off shot it's an irregular measurement error of quite significant size so if you take those two out of the equation and calculate our average again 26 point of us gives us an average of 25 oh I'm stupid twenty-six point five zero three and when I look at the numbers I'm very certain that this is this is our diameter I would definitely ditch the last digit the micrometer I'm using is mr. Torrio one micron it has two micron error that's plus minus two microns on the reading so I would definitely ditch the last digit in this case especially as it's a transfer measurement so I'm I'm very certain that this is twenty six point five maybe plus minus 10 micron to be on the safe side I'm I'm no expert in statistics my sample size is relatively small but taking fifty sixty measurements with telescoping gauge gauge just get sold over time and you have to take the the fatigue off of the person who does the measurement into account to so for the small test the sample size should be okay it's quite interesting how close they are except for this one which is twenty twenty microns off but still interesting interesting little test might be obvious but I've changed the tool post on my leaf I used to have a Swiss drip on 111 dovetail style - tool holder on this machine and for various reasons which I will talk in in the in the next few minutes about I changed to a multi fix holder multi fix is it's urgent it isn't in Switzerland but now every man and this dog makes them this one is X branded these are made in Germany a really nice quality nice tooling and of very reasonable affordable it's still a lot of money so it's it but it's a it's a tool post obviously a quick change to post with tool blocks that look like this they have this this serration here and the tool post itself has the same serration 40 40 positions that means 360 divided by 40 every 9 degree can insert the tool block that means that the ID and OD tooling is the same or the blocks basically there are of course boring bar hold us which go in like this which can hold a boring bar or a sleeve for a Morse taper I have a more simple to sleeve for drill chuck or or drills or you could even put a grinding spindle in one of these 30 millimetres a lot of meats to work with yes it's a it's basically standard here in Germany or probably parts of Europe in on industrial Leafs there are not much alternative pirat makes the pool holder that's also dovetail style but apart from that and the tree pond it's basically all multi fix that's almost standard a is the size at this one there is one size smaller AAA and up they go to something like C or even larger Vernie basically a crane to change the tooling at work we have a shovel in 1/35 lathe and we run it with a multi fix B next size up which is basically one third larger almost like this so I had to take some minor modifications to my solid to post to be able to put the multi fix a on here so not too much of a not too big of a deal it it's pinned in place with two pins and located we our central dome this large post here in the center 16 millimeter hardened rod which is basically the nut which holds the tool post in place this is also again my my mounting point for an indicator and you can use the barn boreholes and just at the other tooling blocks in every orientation that you want which gives a lot of options and that's one of the one of the main reasons that I switch from the creep on to this system the tree pan is an excellent system no doubt about it it's very accurate well made usually very repeatable which this one is - and it's it's a simple system with the dovetails the tooling blocks are easy to make yourself the problem is you either have to buy the tooling blocks in Switzerland these parts they are like hundred and twenty euros apiece which is a lot of money or you make them yourself and I resorted to making them myself most of the time because it was a hobby and I had time to do it now that I run this mostly as business I don't have that much time anymore to work on personal projects to be honest I worked the most most of the time on customer parts or fixtures to make customer parts so a little time to mill something as simple as a as a tooling block for the quick change tool post that that was basically one of the two main reasons price and availability the other reason is a tree pond tool holder the the base tool holder looks like this it's angled that means and it's fit mounted in a way that this is oriented with the cross slide travel you have your straight tool holders for mostly for OD work like this and you have these angled blocks which are for ID work oriented like this you have them probably seen images on a million times all these are made myself so the problem is once you made up make a block either a ID or o ody one you're committed to it this is you can it's very hard to use this for OD work you can with a over right hand over the left hand a tool but doesn't always work so basically I have about half of my tool holders or ID holders and the other half is OD ho or OD holders I have some specials like like the drill chuck or parting holder that's a different story but with those you're committed and if I need now like for a certain job like 15 OD holders for some weird reason well that's a problem I don't have those with the multi fixed every oldie holder can also be used as an ID holder or if I need to as an angled holder which can also have to use is that not very often but it can be useful so net the other main reason just flexibility each tool holder can do everything here within its its overall shape of course this will not hold square six millimeter tooling but I have some ideas for these large 30 millimeter holders apart from boring bars for one grinding spindle and second a compact an even more compact rotary broach than I already have that goes directly in one of those holders this is the Hemingway rotor broach that I made years ago works excellent goes in the tail stock but tail stock so so mm and we are in 2020 so wouldn't it be nice to have a rotary broach that's it's fully engaged in such a holder just an idea just playing around with ideas and make it more heavy-duty make it with needle bearings needle roller bearings and needle axle bearings make it really heavy-duty go in here and you're rocking making hold of four for these four-rotor brooches they can power feed them just some some ideas what I want to do with the system and the nice thing is if I need an external holder I can buy one I can just they're readily available oxen Germany makes the pivot tool is an importer which sells these made in Far East he seems to have a reasonable good quality control and many other places and also there is a huge second-hand market for these you should go to a use machinery dealer usually they have they have these at hand if you buy one from AXA they are around 50 to 60 euros one compared to a three pound holder which is 120 euros that's a pretty good deal the the teeth on on the Aqsa ones these are ground if I had to guess these are our profile ground with a with a dressed wheel that has the counter in it in one pass friend of mine has a wire EDM he he cut a bunch of them on the wire EDM that works also quite nice look it looks really good the PV tool ones which he has made in Far East are also wire cut problem will fire cutting is in the surface roughness if if you don't do enough skimming pass the surface roughness is quite high so the slide ability of the multi fix the ground ones is quite nice please go in really cool locks we are an eccentric bolt back here height adjustment if this screw here and this countess group using the same square drive wrench for both the clamping screws down here and also for this lock nut okay a little float back in time he'll on machining down my soul to post feeling fairly small coridan note that this allowed me to go quite aggressive coupling and buzz off that the two are quite quickly I'm using the mill with ten millimeter tool in here that centers on the mill fix tool post I'm using that to figure out the position of the of the tool post on my solid tube house mount I just touched off on this side and this side of an edge finder and now I'm just moving the axes around to position it nicely in this direction I'm just going with the end of the tool holder flush with the block here and in this direction I'm going a bit further back than I had the tree pond because I want the center the of the tool Verta cutting action the cutting force goes down into the the cross slide and then into the bed slide was a carriage I want that to be a little bit more to the center of the Cambridge not as far not as far out as I had it with the tree pond so this this is probably it this is probably the position I'm going to put it [Music] so this is cast iron so we're going for about one and a half times diameter thread engagement it's a 10 millimeter strat so we're going to make the thread 1/3 15 millimeter long so threat needs a little bit longer something like 20 millimeter because of the lead-in on the tap and we need to drill even a bit more deep for deaf clearance there we go that's 25 millimeter deep if we can trust the internet the impossible task tapping with a keyless chuck touching off the depth with a scale okay you saw me milling down the solid tool post about seven millimeters surface grout to top and then I drilled the holes for the dowel pins there are extra holes here and here because I assumed that the orientation of the holes matches to the orientation of the teeth but in hindsight that's not how would you do that it would need a fixture that aligns and reality they probably just hold it like this in something like a large collet and drill those two holes maybe even before they cut the teeth that means the orientation between the holes and TV is not existent and with those two holes my my tool post was off and I could not adjust it by by slightly moving the solid tool post around so that was no good so it decided to drill two more holes and this time I used the I used the tool post as a drill bushing I put it on here I this was mounted in the lined I put the multi fix holder on here and I had a boring bar holder with a piece of round stock in here that I used to align the multi fix by turning it I mean an indicator along then I bolted it finally down then I took the whole solid tool post off still with the multi fixed mount that I took six six millimeter dowel I aligned each of the holes on the mill then I drilled and reamed them six millimeter six H seven put the Penton turned a new post with twenty millimeter which is this diameter here and as you can see that's not to fit I was after and the alignment when I put this all together and put the tool post on to block on it it's pretty darn good so let's put this together we have the the clamping band this goes around like this and we have this piece this is the the marker for the other rotation here's the the washer with the pointer on it see this goes on like this I mean you know a tool tool holder like this and we align this pointer with the zero mark this is just a help and then we put the nut on in this case it's not even it's not enough that it's a piece of 16 millimeter case hardened and ground linear shaft which allows me to use my indicators on here take or they're adjustable wrench has a flat ground on here tighten it down pretty good and we're ready to go multi fix wrench there we go okay that's all I got for now I hope I was able to assemble a kind of interesting collection off of topics the project I'm working on currently are of the kind that I'm not allowed to share so I have been provides a little bit thanks to all who who support me those who support me on patreon those who obviously watch my videos those who comment so thank you all and stay safe be kind to each other and I'll be back [Music]

Channel: Stefan Gotteswinter

Views: 56,568

Rating: 4.9675074 out of 5

Keywords:

Id: 9OwFB0d-ock

Length: 45min 16sec (2716 seconds)

Published: Thu Jun 25 2020