MAKING AN INSERT BORING BAR

hello everyone welcome to my shop I'm Robin and today we're going to be fixing this situation this is a quarter inch diameter solid carbide boring bar with a coolant hole and they use TD HB inserts little teeny 5/32 IC inserts with 15 degree cutting angle because of such a small bore these inserts work really good this bar worked reasonably well for a while but the head fell off and as you can see here the taper that they have on this is not is way too steep it's not giving enough bond area and I actually saw some reviews where people said the same things works ok until the head falls off so I'm not going to repeat that especially since the bar alone now is roughly in the $260 range just for the bar no I cannot make replacement heads one of for that price but I'm gonna make six of them because this is a handy little bar and a kind of a fun project and the quality of these wasn't all that impressive to begin with this I actually the first one I got the seat bottom was so non flat that it actually cracked the inserts when you tightened it so yeah it just lost my appetite for buying more of them so I'm going to show you the process and design details of how I go about making these and obviously since I'm making some extra heads I'll probably do up another solid bar without the through cooling as having a spare on hand here we have the cross section of the head you'll notice I've got this conical much shallower conical seat I originally had this designed to 15 degrees but I happen to have a D bit cutter to do this plunge this taper that's at 22 and a half so I just moved it to 22 and a half idea here just beat getting a more engagement that's getting closer to cylindrical than a flat face also the having a thinner wall thickness here to be able to have the heat get in from the outside and to the bar quickly because we're trying to not anneal this head in the process now we're moving on to all the other features we have to do in here we've got the big cutout here which has a three degree back taper matching the back taper of the bottom of the seat the holy insert sits at a 5 degree front clearance and we have a hole here to not need ultra small cutters to get in to do these tapers the tapered walls and the clearance and 256 tapped hole which is the the standard insert size we have our five degree front clearance from here down we don't want to follow the 15 degrees of the insert all the way down because when we come back here we'll see that if we did this wall would get very thin we're almost the threads would start to pop out through this so you do need some clearance on the front but not the full 15 degrees which is pretty steep and actually because of the 3 degree tilt here the effective front clearance is only 12 degrees so this 5 degrees is a good compromise you can feed fast enough in theory where this would start to rub in but not with the finishing insert style of turning that we're going to be doing with this one of the key things that I want to point out here and what I'm doing and what I'm going to be showing is this has a lot of different operations drill tap roughing out the pocket milling the pocket walls putting this in putting this relief in front clearance all these things and with a machine without a tool changer or even if you had a tool changer it's just a lot of a lot of work where on my machine if I'm doing multiples I need to come up with a way to put this part in and out of the machine in whatever orientation it's in whatever setup it's in multiple times and have it repeat each time such that changing the part is a quick operation but I can set up the tools do whatever the setup is and run that operation on all six pieces that I'm making so I'm going to try to show you my train of thought here on how I came up with the method to make this mountable accurately quickly and not a big deal initially I thought okay you could grab by you know make this a little longer and grab with a collet call it stop but then you have to rotationally orient these somehow and even if you put the tab on the college stop and something to reference on the part you've got to play in the key way of the collet that can bite you in the butt it's not perfectly rotationally aligned so I'm going to show you here by opening up the sketch of this revolve to see what I did here and you can see I'm using I'm using a lot of things on here just sketch wise to do some math on the sketch even though it doesn't have anything to do with the part and what I thought is you know what let's put a tapped hole in the back of this and use a 10 millimeter set screw m5 set screw put five millimeters of engagement in the part in this part five millimeters of engagement in the mating mandrel and I'll just add some dummy you know some excess material on the end here temporarily to give me the thread engagement I need and that's what these lines are for there's the OD of an m5 thread where it runs into my taper this is where the tap drill size runs into the taper and I literally don't even do a drawing I just use these values and this overall length as my design drilled in this far for at the corner of the drill bit and then tapped them fully and designed you can see here I want these to be some have some excess material on them I'm going to have them 1/64 over a quarter when we're done before we solder so I made a nine thirty Seconds hex and then I just used it to determine what the cross corners was on the hex so that's what we're doing just making this longer putting hex on here I'll turn these leaving a place for the hex on here but you're all probably thinking wait a minute just a thread that's gonna be shaky that's not going to repeat well well it turns out that if I run a set screw into this heart lock it up in here really hard and then change that whole part as an assembly with it with this set screw basically rigidly held in here as if it was an integral part of the the piece and run them in and out of the the mandrel and the mandrel I'm using in a 8 millimeter pull dal which happens to have m5 threads in it and then I just hurt hard turn the end of it off so it has a good bearing surface so you'll see when I turn these and I check for the repeatability you run these in tighten them up may had tight final turn this to the my oversize diameter and try the repeatability it's very good so that takes care of that aspect so that's how I'm making these able to go on and off of this or this mandrel and the mandrel can poke out enough from the collet face of my index or such that my mill tools and things won't be crashing into the face of the collet or the indexer getting to the all the orientations and and places that I need to get so I thought I'd share how I go about making an insert pocket with a particular insert and the orientations and I find this way to be pretty helpful not saying it's the best way but it works I started out by modeling the insert what the relevant things are important the corner radius the clearance angles the thickness everything correct in this particular case because I wanted a 5 degree front clearance what I'm doing now on top of just modeling the insert is I am giving myself a way to locate and mate this insert into the pocket head as an assembly so here's my inserts with the planes and what I've done is I've made this 3 degree top plane intersect this sketch line that was on the actual part and it be at 3 degrees so if I make this in my part the level I'll have my 3 degrees back clearance and then I made a plane perpendicular to that through the same line that lets me orient the part rotationally with that and then we just have one more degree of freedom that we line up on the part which in this case is going to be the back edge of this radius tangent with the back edge of the quarter inch bar so what I do is I bring in the part the insert you can just see the little tip of the insert poking through here and I'm gonna go to wireframe so you can see what's going on here there's my insert that is in the part and I've made the planes of the insert and added some mates here on the tangency on the back of the cylinder so that this is oriented properly and located in space relative the part now I'll go back to solid mode here now what's going to happen is I'm going to I'm going to it's in rollback state now and all of the features here what I've done is modeled using in context off the insert so I've added some planes some things you'll see cut cut extrude here's where I did the five degree face relative to this bottom edge and then go here and get some more items in the there we go there's the main cut out that I'm doing basically flush with the top of the insert there is the actual insert pocket and you notice that this isn't isn't cleared out yet because the hole clearance hole isn't in the back yet there is the big upper relief that we did here and then we'll do that now we've got our relief hole and our tapped hole and so you can see but doing that by modeling all off that insert what happens now is if I change my mind and say oh I want six degrees I can go back back and edit the insert geometry and change the front angle or the the back break angle of the three degrees and everything will update in this part you can actually have different configurations for that so that's very helpful one other thing to keep in mind that may or may not be aware of with inserts is these threaded holes are actually offset into the pocket to pull the insert back in there they're not actually just centered because they have to put seating force in here and these values are not something can just calculate so I have about five thousandths of offset in here and I will drill and tap the holes first in that location and as I that everything will be done except this final mill of the the actual tapered walls of the pocket and what I can do is I can do them in my nominal location I can use my tool diameter all set to make these narrower and I'll actually check put an insert in check it see if it's too tight and I can just keep moving these walls out a little bit a little bit at a time until I get this right value once I do that on the first one then I can run them all with that amount and have just the right amount of seating force back into there and hitting at the bottom at the same time there's just no way to calculate it I've talked to people who and maybe there are but the people I've talked to that make insert tooling like this say no it's somewhat trial and error as a lot to do with the clear thread clearances the you know the shape of the screws and all that so it's a real can of worms so that's that's basically the modeling method I use to do this I just thought that might be helpful to be able to do it that way and then realize that all these things update as you well know when you do 3d modeling like this your sequence of events and things can make your life miserable or it can make it easy and I think this is one where it makes it easy this is actually a SolidWorks drawing of the pocket and what I use this for was to design the cutter parameters and where these hole locations would be for this relief hole and what I've done here is I've said I'm making a 40,000 diameter typically and I'm going to get this wall here this setback by just making a step in that same cutter which I'll show you when I when I do the cutter but by doing this I can right here I'm clearing the sharp of the insert if it had a sharp tip on this back edge but then I come up here and say okay up here to where the cutter has to cut to I'm going to set that as my point that I need to be tangent to and then this lets me know where where the the location of this hole needs to be so in the diameter so working with those I come up with these dimensions to say okay this is where it's going to where it's going to be and this gives me a lot longer engaged length on these faces than the original seat they put a much larger milled slot in here that took a lot of the strength of the the length of facet that that engages with the tool away so just showing here using sketches to determine where that is here you can see I have modeled the cross section that I would revolve to design the D bit cutter we've got the forty thousand tip diameter here from our previous sketch we've got our 15 degree angle to match the clearance that's on the insert then we've got our five thousandths radial step over there's nothing critical about this it's just a relief so that the edge of the insert comes here and does not get chipped by being pushed on by the seat in case the seat angles a little bit shallower it would tend to break the break the insert edge so this is just below that the thickness of the insert so this is what I'm going to use to do my my D bit grind and I'm actually going to add a dimension here that is this way this orientation so that I know how far to move from the tip in with my diamond wheel when I go to cut this and then back off to do the other or vice versa grind this outer one first and then grind this one to this depth and this can be smaller needs to be four to thousands or smaller so this isn't critical other than it changing the depth so I'll check those things out in the comparator I've added this dimension right here I've had this construction line to come out here and what that represents is the outside untouched corner of the cylindrical blank where I'm going to touch off on and then this is how much I'll groove in the grinding wheel in feed direction Oh 41 I'm gonna make it Oh 42 to make sure I'm below this to come into here and then this I'm going to back off the 5,000th really which will make this 37 in feed from there so I had these construction lines to be able to tell let me know without taking it out of the machine to go measure and trying to get set up again to get this in the ballpark so it should be good first shot when we check in the comparator the material I'm using for these heads is by count 44 which is a pre heat treated H 13 tool steel it does have so few additives to make it machine a little better at that 44 Rockwell range but really good stuff and it reads it's a hot work steel so it retains a immense amount of its strength and hardness at elevated temperatures so at roughly a thousand degrees or so that you would think for silver soldering maybe 1200 that levels are still very high and you'll see that I'm going to use the heat sink to keep the actual pocket from getting anywhere near that temperature so just an excellent all-around steel extremely strong you know two hundred thousand psi in it's at room temperature and the yield as a minimum of a hundred and sixty thousand so really really good stuff [Music] the stop locks are pretty handy for relatively precise repeatable positions going in facing this at b0 with this tool and then turning it to 328 for $650 switching to my parting tool while the edge party to location [Music] or off a little bit game for the back edge [Music] and then all 2164 it's collet for that diameters I just turn excusing collet wrench handy item just snugging this up move boy space to take your head to your next operation and in this particular case I'm going to be putting a hex on the end here as I showed you so I'm leaving enough out for that to happen and be able to grab onto this as I put these parts in and out drilling and tapping the hole so always good to consider your next operation if you using the same collet okay now I'm facing these off each one I'm just popping them in and out of the collet as I'll be doing all these operations I'm sitting it out this is a real quick way of way repetitive operations on the machine one of the great advantages of kaulitz in general it's just that repeat especially this style stop in there and you just get the uniform now we're spot drilling the end [Applause] watch what I'm doing on my digital off one out stick another one in [Music] it's the beauty of having the solid compost and the repeatable position of the drill chuck now with the tech drill popular piece in [Music] watching my deposition my [Applause] by the rinse repeat now we're on to tapping now I'm taking a semi bottoming tap down in there to go down till I hit the bottom which doesn't take much because I've got pretty close in the lathe that's it debate grinder allows you to make really nice bottoming taps out of taps that are lost their life or normal tapping going down in here and I'm getting the final last aunts degree of threads in there to run right into the bottom we have the indexer set up in the middle and as I mentioned before we anticipated the collet look call it stop locations for milling these off so now we're going to mill the hexes on already have everything set height wise this harding indexer is really really nice set for six divisions a little more up close and personal so while I have the college set up here you're using it to hold these still while I run the set screw into them m5 by 10 set screw and this set screw is going to stay put as we described through the process it's just an easy way to hold them keep them from spinning while you tighten the set screw up so that might see the end tool here that I'm going to just come back and face this off till I get back into the threads [Music] that gives us a nice flat surface it's true it's an eight-millimeter Dow pin already has the m5 threads in it so I'm using this as my mandrel so now we thread our pieces in one at a time [Music] torque this up to the maximum seating torque here good and firm power on this 266 to match 1/64 over reporter Collett because we'll be holding them on this diameter afterwards Oh low-speed break the edge we're gonna loosen and retighten and check TIR so we're checking there and you can see that's plenty good run out as far as repeatability of position that's why we did the threads first with oversize so that we could make it run true to the threads how they see I've shown my college before but I'm not sure I've actually shown me doing it and this is my preferred location to actually do the screwdriver because it's an area that has you know doesn't matter if you if you mess it up if you if you want to look at it that way you can file this off and it's not a functional area and then once that's in you can just snip these off with the flush cutters you notice I'm sitting in aluminum soft jaws here and tapping in here with a nice paper bladed screwdriver makes it real easy using the three thirty-seconds preferably Viton a ring stock snap it in push it down a little further make sure it doesn't poke out the top it won't matter the collet 'el the closure will will push it in if you don't and in no time you're you've got all three of them in without any struggle and without hurting the functional aspects of the of the collet and you notice if you put it in this way i'm turning a 90 degrees so that the bend gets straightened out in the in the groove so I'm not fighting it going into a curve you need a little bit more here there we go not fighting it going into a curve like that lets me put it in like that straight pop that out snip it off and you're good to go it's finders on the end and the sides of the piece to get on Center and there were like location this same setup as before with the index or in the middle but now we've changed the millimeter collet put our eight millimeter pull down in that we used as our Harbor and we're putting our parts in threading them in and we're tightening these mad tight and this is our basically our repeatable parts position and since we have a lot of different operations to do this allows us to do per tool since I don't have a tool changer on this machine allows us to do per part or per tool every part okay that's all for that tick part out and we'll take a look at this now you can see we've got our relief and we've got our three degrees back break on this I'm holding a three degree block against the base of the indexer and I'm tramming up with the head of the mill just to check my alignment which is plenty good enough for what we're doing here as you can see here I'm just tilting the whole index are in the vise and I just used this three degree angle block on the base here for training purposes so does just as a double check I'm trimming the surface that we've just milled previously the which was milled on the three degree angle to make sure that this jives so I'm up on the radius now should come down to zero and then drop off at the end there we are sitting and then let's drop off at the end that come back they'll see it climb up hit zero stay there on the flat and then start to climb so we're good since I tilted the dividing head indexing head I need to re-enter the lip here for the axial position the lateral position is still good because the flats on the indexer haven't moved relative to the vise there's real small animals always a good idea to indicate in make sure you got your flute your flutes in the cutting zone cutting on the exact same location you can gently tap on here with a I use a little bit of piece like this and [Music] brass bunker and just gently tapping you can't move it miles but if you're only out you know you have thousands or something you can usually tap them in so they run nicely [Music] [Music] [Music] [Music] [Music] here's what the pocket roughed out next will be the 15 degree cutter going to grind up a D bit we're here on the D bit grinder we're going to have this cutter to give it the cutting flute I'm going to rough it with this rough wheel and then put a 600 grit wheel in and you're going to see this come into play with our doing our tip just a little note this is my take on keeping grinding wheels in shape grinding wheels will wear from the edge that you're taking the most material off there and where the most there they're going to diminish to less where as you trail off so if you in feed here and then pull off this direction as opposed to in feeding on the outside and diving in this way which I see a lot of people doing you'll keep this wheel shaped where this outermost edge cuts first and this cuts last and what that does is it lets the arc of the of the grinder generate your flat not the shape of the wheel as soon as this wheel where is where this outer edge is worn away more you're not going to be able to generate a surface that is flat full-length on this thing it's going to have a taper that you can't get rid of because the sweep of the wheel can't get rid of it because there's there's no outer edge here to basically cut and and generate true to the to the move of the machine so always good to keep that in mind same way with surface grinder wheels it's going to the way each reverse across is going to leave an outer edge so if you have to do sharp corners it's always good to down feed at the corner and Traverse off such that that outer corner stays sharp so just a just a note pays to make a nice wrench the most important part about this ranch is this extension and all it is is an m5 that's been drilled and tapped into the end of this m8 such this this goes down and hits in this in the tapped hole and the spindle hits at the bottom it doesn't have this hitting on the threads of the spindle that hold the that hold the part on the hold the wheel on so definitely worthwhile to making see this works really well nothing I invented it's just just showing you what matters here that quick wheels off my 600 grit wheel on you just absolutely have to use hubs it's just especially with super abrasive wheels like this it just doesn't make any sense to do it otherwise now I'm going to take the 600 grit wheel and I'm actually going to take this size now I'm taking a break here and measuring this and seeing how close I am to my oh six t25 thickness and not know how much to take off so I'm at Oh 66 so we've got the three and a half thousand to come off the face there so we'll go ahead and take that off here you can see that 600 grit will finish really nice and corner holds well here I'm setting my 15 degree angle of the actual cutter on this particular axis like this here I'm setting the actual cutting lip angle in this direction here I'm doing the actual end cutting relief so I've got my same 12 degrees that I'm going to use on the on the side of the flute I'm using on the end and then I've also cocked this just a few degrees this way in this direction to make sure that the outer edge of the lip cuts and doesn't give me a flat bottom doesn't cut at the center [Music] [Music] check out the reflection of my fingerprint on the bottom of that cutter from the 600 grit wheel that really leaves a nice edge very important on carbide get a nice relatively unzipped edge quality let's show you a little feature here you've got your infeed here on the D bit grinder which is your main rail feed and this is calibrated it is from the factory and it also is on mine where I modified it so I know what this means this is 50,000 s per turn but you can't move this dot in this dial this dial doesn't isn't reasonable so what I can do is since this has also has the spindle feed where you can actually feel speed the wheel spindle itself in with a lock right here this allows me to zero this dial and then come in and touch here on the outside edge of the tool you in feeding with the spindle and then locking it so it's a way of getting a zero even though my main dial isn't zero able an important note in all this is after preaching to you about using this wheel so that it cuts right here on the outside edge as is going to be the last place to cut so all this is below that cutting zone so it's almost like a fly cutter with this being the outside edge and you're intentionally working this in here that means it's very important if you intend to zero that you got a zero out here where that's things just touch and so you want to be just about ready to fall off the edge right on the corner when you go to set that zero otherwise you're going to be off by the amount of where wheel where that this space here is below the actual cutting edge so now you can see the I did my my cut at a 37 what I'm doing is I'm in feeding on the bottom and then slowly cleat creep feed grinding around like this in one pass and then stopping it by my 93 facet point but now what I'm going to do is I'm going to come in I'm going to move in my five thousandth to be 42 well my dial back here and I'm going to gently come in and touch the wheel right here to get my zero and I'm actually going to set my stop here so I'm resting on the stop wait till my stop hits and starts pushing me off here there we go I just came off so right there now I'm coming in and I'm going to just come in and visually touch the side here right there and I'm going to come here and zero my indicator so I'm just going to grab this loose and it's mounting and bring this up here like this and this is going to let me feed in my forty seven so now I'm going to I'm going to feed in my I think I'm just going to go to 40 the insert thickness is Oh 47 so that's only like seven thousands away from the lip so I'm going to stop right there that's how deep my little secondary lips going to be so I'm going to stay put there okay so now on this we're going to come all the way around to the back and I'm going to in feed where I'm clean off the part on the backside and I'm going to turn it on I'm going to feed in my mount and then creep feed around so this should be smaller than one millimeter which I can see here it is and obviously the back is cut off more so you can't go direct measurement here but that looks like we're in the ballpark so we'll take this out so we can take a better look at it so here's the backside of the cutter they're charged five thousand step in there there's our cutting edge see that's shine on that facet that's the actual flat facet of the cutting edge at the 12 degrees and then we come around here to our front face that we did in the beginning and we should be ready to roll we'll put this in the comparator and see what the tip diameter actually is cutting at here we are looking in the comparator and I've got my eighth inch diameter set it up back in the back here and I moved over so I'm centered with the lines we're about 18,000 off center here which means we're cutting about Oh 36 diameter here and then we've got clearance for our 47 thickness here and this rolls off meaning it stays away from the cutting edge so it won't tend to chip it's going to hold it down here in the base of the insert which is what we were after here I'm spot drilling for the insert screw there's the spot drill for the for the in search screen drilling each hole manually by the rinse repeat little hand tap action here this is tough stuff this is a 45 Rockwell each 13 tool steel so these OSG taps are up to the task but nice and slow and gentle is unhurt and obviously there's a very short distance to the tap there and just going to keep this closed to keep the top from wobbling around as it back out when the mill out now with the D bit cutter it's going to put the 15 degree walls and the stuff and skim the bottom again [Music] [Music] [Music] [Music] [Music] [Music] I've already adjusted the full diameter to get a good seat of this pocket and this is where I was talking about making sure that the screw pushed back into the seat and seated putting pressure on there the 5,000 offset I do is a little bit too much so I had to cut the pocket a little deeper but it doesn't actually hurt anything doesn't doesn't change anything at all but this is seating well it's able to tighten through the bottom the inserts sitting on the bottom and one important thing to do when you're doing these is to beber the bottom edges of these inserts because what can happen is they're dead sharp and they can actually get a bite on the wall if they're sitting above and you got to push them down and end up snapping insert because the inserts actually chewing the wall so I break the edges on these such that they can't do that and make sure that it seats properly let's say if something could bite you in the butt if you're not aware of it this front has excess on it and we're going to grind the relief and the back five degree angle on it on the D bit grinder we have in this direction the back tilt we have the 5 degrees and then we have also the rotation ly five degrees past square this way to put the correct angle on and we have a CBN wheel on what we're looking for here is right there that seat that this is flush at that corner and it's hard to do me hold that and film at the same time but trust me this is flush so this is not interfering with the cutting lip but this is only 5 degrees this is effective 12 degrees on the actual cutting edge you know I'll just in feed to my same reading and so repeatable here [Music] and feeding on the inside [Music] that's it now is a really good time to say to yourself self did I really do every operation that required the repeatable positioning because I'm getting ready to take the screw out and do the machining on the back and as far as I can tell I have but just as a general principle always good to count your parts when you're doing multiples because sometimes you miss one and then you move on to your next operation and it's like ah so we're popping the set screw out now we're done with it and we're going to machine off the excess worker machine the hex down and we're going to machine the length to the correct length [Music] that's it that's what we need on there so now boy we'll do all these just want to reiterate that one of the big things of this video is the whole process of design where you think ahead to the machining processes and do things unusual like adding material or doing them in doubles and then party them in half when they're done and different things like that thinking ahead don't think just the part think process through it through the entire thing so I just want to make sure that didn't fall through the cracks that that if we had started with this piece here things would be very different and just that simple thing of starting with this mounting system design in mind made this very very easy I have my D bit cutter in here that I mentioned before that has the 22 and 1/2 degree paper on the side and I've zeroed the tip on the end here and I also went over in the comparator and measured what the effective diameter of this lip is so that I can know where to go because I'm I'm holding this in my drill chuck which I know the the offsets were that's on center so I can just move off Center the amount required since I know the temp dimension of this I know how far I can move off Center in the health center now how much I can go backwards behind Center to face off the bottom as much as possible before I bump the backside I hope that makes sense so the comparator is a really handy tool it's going to put going on here I'm gonna get lined up at my Oh 42 off to the side and I'm just going to plunge in [Music] we go 40 the other way and just like that we now have our part you can see a little bit of the thread engage there or that the tap was that's not a big deal remember we're just silver soldering this so that's perfect that's what we want for our mount to the carbide so now we'll just put these in lather rinse repeat something that might be missed here if I don't actually say it out loud is that D bit just made something that could have been a lot of operations a whole lot easier since it cuts on Center Heights wise you can plunge in like it did so it's removing material like a flat bottom drill and yet putting this the shape in at the same time so I just didn't with that missed that that deep it isn't just a another way to do it it's a very efficient way to do it here I've ground the end back on the original to get large enough that it will clean up when I do the shallower taper here I'm set up at 45 degrees just to knock little chamfer on the back edge of the bars there's a nice chamfer on there just didn't get cut by the tail into the carbide your setup at my 22 and 1/2 degrees and I'm going to blast off a significant amount of material just to get my general teper adjusted what you saw me doing there with the very heavy in feet and then a very slow rotation like this is basically a form of rotary creep feed grinding it gives a larger contact patch for all the diamonds to work on so that a larger area of diamond wheel is taking the loading that you're doing yeah there's a happy medium there you go too much and you've got too much engaged pressure too much rub and a lot of heat but it's better than just little teeny and feeds were almost just a single line of particles at a time is taking the cutting loads so it's very effective for removing a lot of material quickly what I'm doing here is I'm just checking before I get too far down I'm checking and seeing how the taper fits and I can definitely see since this outer edge here is staying put and I've got this rock I know that my taper needs to get shallower my included angle here needs to decrease so I made a couple tweaks to my angle here a couple tries and not got it now where I'm getting it no no Rock I'm not saying it's perfect but it's plenty good enough for silver soldering it's there's no play there very important when silver soldering carbide to get rid of the oxide layer see this dark brown here and then this where I've taken this very coarse diamond file and scuffed off that oxide and also scuffed off the where I ground to get a coarser groovier finish to get the mechanical tooth on the carbide that helps this dead smooth polished surface doesn't help for the silver solder to wet as well and get as much surface area to get a good bond on so very important to get rid of that oxide [Music] keeping the machine pieces you can see the part here on the Left I have scuffed up with a diamond bur for diamond mandrel with at very slow speed just to get rid of that glaze II smooth surface there you can see the difference in the reflection here this has not hardly any mechanical tooth this has a lot and the silver solder will wet better so putting coolant hole in the two of the heads to go on the bar that has the coolant hole on the carbide and I've lined up I've got the drill centered so it doesn't move laterally when I go down into that radius of that hole at the bottom and I'm using the carbide circuit board drill right now just to spot with and I'll take it out and use the high speed drill to go through till I poke out the back and I'm intentionally not lining up with the hole in the carbide bar because the chips had a tendency to run down in there and pack the hole up full of these with real fine little chips and they were real bare to get out so I'm going to spot this now with the carbide [Applause] I just wanted to get enough there to get a spot for the drill to start into because the carbide drills did not like breaking through an irregular face on the opposite side and I don't want to be a worst case I just use it on a one that doesn't have a : hole but now I'll go through and I'll drill this with the high speed drill so there's our coolant hole it's above the insert but as you can see the axis that I formed here I'm actually into where the insert body is so the coolant is going to shoot down onto the top of the insert and blow off the edge so I actually had some thought about what how I was angling this thing so now I'm going to do another one and we'll carry on so here you can see how I have this whole angle downhill so it's above the back of the insert but pointing down cutting right through the face of the insert so it should spray off the face of that well it's going around the screw but should should be pretty good and then this comes through in the back and is not lined up directly with the center hole and I'm just going to put a notch in the carbide to let that Colette go from the end from the hole up to here to get into this into this hole here's another shot of what I'm talking about of how that hole I'm oriented with the X's that hole the hole is actually shooting down into the face of the insert and I just used the back of that hole to line up laterally to kind of guide the drill I'm putting a a like a 67,000 diameter hole in the bottom as a place to put a piece of 16th silver solder into the joint into that hole to be able to wick in as soon as it gets up to temperature so that I'm not trying to add silver solder from some other place so this will control the amount of silver solder and it should wick in nicely and I'll be able to add a little worth at that hole if I need to some might be thinking hey you said to think about everything that you needed to do to all the pieces before you got rid of the set screw system and the issue there is is that this is where the set screw tip was so that's why I had to wait till now to do it so I'm using my trusty safety cell 56 it's the highest capillary action fluidity silver solder and lowest melting temperature of the hard silver solder 's and I'm using these trashed stripping pliers to be able to cut these off without leaving a huge burr where a regular pair of cutters would smash the ends and not allowed to go into the hole this keeps it round enough to drop into that o 67 hole to fit properly so what I was doing there was making this pocket that fits this contour that's going to be part of the heat sink to keep us from tempering back the pocket so here's the two pieces I've got them clamped together here with a piece of brass shim stock parallel clamps I've got this set where this come come in and go like this so I'll just put a second clamp here and this is going to be our heat sink area to keep the seat from getting tempered back now I'm going to grind a clearance around this and develop the end or just eyeball we have our soldering heat sink grabbed in the vise we have our part in there we have our secondary clamp that's actually applying the gripping force up here at the top we have the heat sink sprayed with or on nitride spray it's a good mask keep things from brazing if you've done any silver soldering you won't be long before you silver solder something to your heat sink so this stuff z Y P coatings sells us expensive but it works really well in this application I've also troubled this in the vise until I have this alignment so this this is level in both directions because I'm going to be using just a weight to hold this thing in place like this without that this would just pop hop out of there from the oiling of the flux and it would just push it right out and fall over and it's never happened to me but I've seen people do it so that's why we're doing the the weight and having it nice and level now we're going to take our high temperature black flux Harris and get this wetted inside here and get this covered put this in get the camera out of the way so it's not keeping us from getting in plates roll this around to break up the the particles of the flux so that this can actually seat then we're going to come back here on the backside and push our little silver solder plug in with the tweezers this is what's going to feed the joint with silver solder always a good thing to have the silver solder in the joint if you can or a line to flow into the joint now that will blow right out of there if I don't hold it in place once I get warming this up so I'm gonna have to do that once I get the torch fired up and we're gonna flow this okay let's see if we can do this without melting the camera hold my silver solder in here let me warm this up gently you always want to give your flux time to evaporate the water to evaporate out gently you don't want to just fry it well in steady wins the race remember we're trying to warm the part not the heatsink but it's very close so it got to be careful to not I got to get enough heat in there that I make sure that it actually flows there were one of the signs that your temperature is good is when the flux turns clear I'm filling the solder moving so I know that it's starting to flow I'm gonna back off now and just worry about my heat and keep my heat breakdown here on the section where it matters there we go you saw that pop up for the top edge there now it doesn't mean quit there we need to maintain temperature for a little bit make sure that that temperature gets all the way to the center you go and stop as soon as you see that first sign of flow you can end up in trouble and I just see that I lost some of my I lost my solder in the back here so I'm going to give that a make sure we had this there we go so make sure this is good puddin float here just the dull dull cherry this only takes about just barely twelve hundred degrees to flow and then I'm gonna back away slowly I don't want the heat sink to suck the that temperature out too rapidly and I think we got a winner there probably a darn good thing we've got the we're on nights right on there or that probably would have been soldered to the fixture so you can see who's got good flow there you notice this did not get high temperature this stayed well below the probably I don't know maybe probably than 800 degrees or so you can see here where the actual solder would wanted to flow down in but it was stopped by the we're on night ride so good thing I put it on there in this particular case so now it's time to grind the heads of these and miracle of all miracles I managed to solder the one with the coolant hole without soldering the coolant hole shut you can see the nice flow of this sucking into the to the from the feed hole that that feed from the inside is very important I can't stress enough how having the solder in the joint is just a good way to not have problems so I've got the heatsink with its shim the three extra heads and the silver solder slugs are all in there ready for either replacing smashed heads on the ones I just did or making extra bars now I'm going to grind the head down till it cleans up [Music] I'll see what the diameter is I'll leave this about hopefully about 260 take another three thousand Soph there and we're good there you have it that's 260 and I'm going to leave that as is I'm really worried about having clearance for exactly a quarter of an inch so there it is good to do a little abrasive brush action on it and then glass bead and we're done the real magic is the flying abrasive bristle brush this trick works nicely for protecting threads as long as the toothpick fits but I've used bamboo skewers also also work protects the hole from getting beat up when I'm glass beading some just threading this in firmly like that and that will mask the hole as I glass bead these and I can just unscrew it take it out sometimes it's hard to get glass bead residue out of tapped holes they're always crunchy afterwards so I like to do this I know glass beading is cheating nigs anything look good and you just unscrew these threads are protected altra sonic clean these and on these I will clean up the shanks a little bit there you go here's the finished product going whole you've got our seats with our relieved edge so we don't break the edge of the insert both cases silver solder we're ready to assemble I've already got blue moly on my screw seated down nice looking good let's go check out the coolant flow there's a coolant flow with just a trickle and as I pump up the pressure here you can see that that's spraying really good on the hitting the top of the insert and flaring out that's that's what I was trying to achieve it it worked pretty well considering the screws still there well commanded this far I hope you enjoyed it and found it educational or helpful that was a lot of fun I really enjoyed making those and the probably took me about six seven hours of time of actual production time most of it was filming time so when you consider there's six of them here and figure out whatever shop hourly rate you want to use it's not a bad deal and obviously it's not necessarily the most practical thing to do but the quality of these is much higher than what I bought so there was a good reason for me to tackle these and and make some some decent ones and it's just it's just a very enjoyable project so thank you all my patreon and paypal supporters like I always say it's not expected but it is appreciated if at any time you think my content product production rate is subpar and isn't worth supporting don't hesitate I'm not going to think any worse of anyone who backs out and says hey that guy's not making enough videos not a problem at all like I said I do this because I want to spread the spread the knowledge and get back to the occupation that I I just really love so I'm doing it more for fun so I hope you enjoyed it I'll be back

Channel: ROBRENZ

Views: 257,137

Rating: 4.8826494 out of 5

Keywords: boring bar, toolmaking, silver soldering, inserts, tool design, machining, tool grinding

Id: zrHD01b0WW0

Length: 76min 36sec (4596 seconds)

Published: Tue Apr 28 2020