Trepanning on the Lathe! Efficient and Tasty.

dialing in my beans [Music] and hello internet my name is quinn and this is my breakfast and this is blindix today i'm going to talk about trapanning which is a very cool operation on the lathe it's great for saving material and for making certain kinds of parts in a really efficient way i think you'll like it let's go in an alternate universe trapanning might be called face parting or face grooving it's when you want to cut a groove circumferentially on the face of a spinning part now it also happens to be the name of a pre-scientific medical procedure so i don't recommend googling that word because you need to see those pictures like you need a hole in your head so obviously you could use trepanning if you needed like an o-ring groove on the face of a surface but it has some cool side benefits a big one is that it saves you material if you need to cut let's say a big circular part out of a large chunk of material like this you might think well i need to center drill and drill and then bore this all the way out and you're going to reduce all of that material in the middle to chips if that material is expensive while you're wasting money and if even if it isn't you're wasting time the other cool use case here is that if you've got a piece of square stock and you need it to be round trapanning is often a quicker and more efficient way to make it round rather than just turning down the od so even if you're not worried about saving stock you know it might actually still be a more efficient way to get your operation done it's also good for opening canned goods but you're going to want to stick to your thicker soups and your bean based products and you want to be quick on that dismount with the chuck what does the tool geometry look like for this then well a good place to start would be a parting or a grooving tool right because this looks very much like a groove that could be made with a tool geometry like that so what happens if we do that here's a basic grooving or parting tool and it looks mostly okay all the normal clearances but if you're getting close look what's happening on the outer radius of the circle you can see here that the curve of the cut is coming in and interfering with the bottom edge of the tool there so we have a clearance issue there but the good news is the fix is intuitively obvious just swap that tool out for one ground like this where the angle on the outer radius of the circle is a little steeper and you can see that now it clears and this is really all there is to basic drypanning tool geometry but you can also see from these drawings that there's an interesting trade-off in tropanic geometry that you don't see in other operations the smaller the radius you're cutting the more clearance you need under the tool and thus the less support you have under the cutting edge so you tend to end up grinding multiple panning tools for different ranges of radii you don't want to just use one ground for really tight radii because it's going to have poor support under the cutting edge but then a tool ground for large radii isn't going to work on small radii there's some more advanced things we can do here which i'll cover at the end of this video but let's start with this basic form i always find it helpful to draw what i'm going to grind so i'll blew this guy up after cleaning it with some acetone and then i'm gonna mark my basic parting profile here it's about a hundred thou wide and three eighths thick and then mark it on the other side where it really should go it's helpful to have the parting blade side of it on the inside of where the tool post will be because it gives you more clearance around the tool post and then to get rid of the bulk of the material i'm going to bust out the angle grinder that'll save us a whole lot of grinding time and it well it's also fun as i go here i'm using water to keep the tool bit cool but i don't know how necessary that is it's fun though and high speed yahtzee with that basic shape roughed in i can address my grinding wheel my least favorite part of tool bit grinding and i can grind it down to my lines so i'm starting with the end here if you want to know more about what i'm doing here i'll refer you to my video on grinding tool bits this is really just leveraging my 10 degree table as usual to clean up those sides i've roughed in a basic parting tool profile i've got about 100 thou of width there and i've clearanced it back from the cutting edge a little bit on the sides i've clearanced the end there as well and i've also clearanced the sides now the question is could this be used for a panning tool as is the answer is maybe it depends on how much clearance you have on the sides and whether it's sufficient for the radius that you're trying to trapan now in this case i've got a little more clearance than is really necessary for a parting tool this is 10 degrees 3 to 5 is plenty but it really depends on the radius that you're trying to japan but let's see if this is sufficient clearance as is for the operation that we want to do and then we'll have to put some top break in there depending on the material that we're cutting or you can just put a little chip breaker in the end for a parting or grooving tool that's often all you need and before doing any actual cutting i'll clean up those grinding marks and burrs with a little stone home as is tradition after that little stone bath this is looking pretty decent you can see how it's so far just a basic parting tool now let's go see if this might work for this test i'm going to use this chunk of 2024 aluminum that was donated by a viewer and this is neat stuff unlike the traditional 6061 that you're going to most commonly encounter this stuff has a 7000 psi higher yield strength than that regular aluminum and it's actually an alloy with copper and i think there's some manganese in there and it's much less susceptible to fatiguing from like work hardening and so it's commonly used in aircraft fuselages and wings so it's pretty cool stuff it's quite a bit stronger than regular aluminum and uh well because of that it's three times the price which makes it an excellent candidate for trapanning if we can keep some of this out of the chip tray we should do so i started by facing off the end as is tradition and i put a light center in there not for tail support but as a cheater hole for the divider as you'll see here in a moment i'm going to blew this up so that you can better see what i'm doing and also because it's super fun to blue things up on a spinning lathe groovy man so i'm going to mark the boundaries of this theoretical part it's going to be a ring that has the same od as the stock and then here's my roughly 100 thou wide cut line i'll use the tail stock here to square up the tool post it's quite important that the panning tool be square so that our clearances remain effective as the tool goes into the work now let's line it up here on our lines and just see if this basic parting tool grind is going to work now it's really hard to show on camera and the clearance on the leading edge makes it difficult to see how it lines up but you can in person see that it looks like that is probably going to rub on the outside radius so all i need to do is take it back to the grinder and take a little bit off the bottom edge there and if this can be curved or you can just make some facets on there just remove some of that material that's going to be near the bottom edge there and this can just be done by trial and error now i'll do a test cut here and see if i can get away with no top break on this tool note that the end of the tool isn't ground square it's biased to the outside a little bit and that helps prevent burs if the japan is your final operation but it'll work fine if it's square as well it is however really wanting to chatter it's right on the edge of chatter here and it's not cutting as well as i would like so back to the grinder and i just put a little chip breaker slash top break behind that cutting edge there just using the corner of the grinding wheel and now let's give it another shot and it's going to be a little noisy until we get through those chatter marks but once we do now it's cutting quite well now for feeds and speeds you want to go pretty modest so this is 80 rpm and this is a 4 inch diameter part i'm a little further from the chuck than i would like to be so chatter is still threatening to enter the room here but i'm managing to keep the door closed with a very gentle feed and lots of cutting fluid and a good sharp tool there with an aggressive rake on it for this aluminum now keep in mind this is a form tool just like any other parting or grooving tool so you've got a wide cutting edge there doing a lot of work so tool pressure is high and in this case you know this is 100 thou wide tool which is a lot for this little baby lathe so you're going to need to take it easy so you can see here how far in i went just far enough to get the part that i want this hypothetical ring that's i'm sure very important for something and now we can go ahead and part it off in the usual way i should note here on my parting tool that i'm really feeling this 2024 aluminum it's parting quite a bit tougher than usual 6061 does on this little lathe and i'm also working pretty far from the chuck here i'm about four inches away from the chuck which is again asking a lot from this little hoppy machine but we are getting it done if we keep the speeds and feeds nice and low and yahtzee and there's our little ring and you can see that the vast vast majority of the stock is still untouched and ready to be used for other parts so this ring could be a bushing or a bearing backer or a ring gear blank or any number of things so what is this ring for uh i guess this let's see if it flies yep that's what it was for so that's a very basic sifter panning now there are some more advanced tool geometries you can use here to get more sophisticated and efficient results especially with multiple parts so i'm going to direct you to a great video by tom lipton over at ox tools uh he goes into uh some more of the gory details of trapanning that i have not covered here it's a great video tom's amazing but that's my little speech entrepreneur i hope you found it interesting if you like what i'm doing feel free to throw me some love on patreon it's greatly appreciated thank you all for watching and we'll see you next time be careful out there catch those beans you

Channel: Blondihacks

Views: 80,967

Rating: 4.9492035 out of 5

Keywords: blondihacks, machining, machinist, abom79, this old tony, vintage machinery, steam, electronics, making, maker, hacking, hacker, lathe, mill, woodworking, workshop, shop, model engineering, engineer, engineering, live steam, machine shop, metal lathe, vertical mill, metalworking, metal shop, jewlery making, diy, home improvement, resin casting, how to, do it yourself, do it yourself (hobby), ASMR, mini mill, mini lathe, tutorial, trepanning, trepanning operation, trepanning on lathe, trepaning

Id: wVPUBJ8mYwE

Length: 11min 32sec (692 seconds)

Published: Sat Oct 24 2020