Composite Master Square Construction

[Music] welcome back doc stools I'm Tom so today we're going to look at the construction of this composite square and what this is is this is the big brother to this Hermann Schmidt master square and what these behave as and say perpendicular standard for the for the shop it's a it's a right angle it's a precision right now I'm much like a cylinder square you would use a square this comparator to zero on your your standard and then you can check parts on the surface plate to determine if they're square and how much either square they are but quantifies their lack of perpendicularity or their agreeance with perpendicularity anyway let's take a look at how I put this thing together [Music] [Laughter] okay now I know you guys aren't gonna believe me but I just kind of eyeballed that thing up there and this just goes to show you that I'd rather be lucky than good any day of the week there's no limit to luck he can only be so good you know a machinist can't leave well enough alone right so we got one down there it's gonna give it a little little dot there let's see I need to go towards it tip over all right you know what I don't miss it anymore so never be afraid to use your sidebar I mean it's such a simple tool and you know you can set it up many many different ways so it's it's just a it's never too precise I guess is what I'm trying to say so sometimes it's just the easiest thing to use they have a nice surface to indicate I've got the clamp to slightly here so the method moves around and try that with a protractor you know it's not that easy so okay so we're lined up on the one of the endpoints of the slot here and what I've done is I've just fished it and found a good a good spot now you can clamp something there and indicate it but these are just lightning holes so we're not super worried about so I got a good line up here it feels like a good line up I should say and we have several cuts that are at the same angle here okay and once we zero out on here this is where you know have a good cat layout and setting your angles accurately makes a difference because now I can just cruise over you know to a node dimension okay and get into my next my next hole now remember what the number is [Music] anyway you get the idea so you can get into your next slot your next starting point and then m/l over to here so and I know the distance since this is a isosceles triangle that this distance is equal to this distance so it happens to be 1 in 5a so I just have to zero and move over 1/2 5/8 and I got it so we'll get those cut out all right we got those angles milled and now we got to swap the setup around and cut out the last bit there now this is actually good juncture to talk about something this is a classic bozo mistake right you're all excited you want to flip the setup around and get onto your your next angle before you take anything out of the vise or move anything just take a deep breath and look at your setup and go oh hey think about it and what else can I do while I got it here or what am I forgetting and that is this whole other side here right now you know I may seem obvious to most people but I just have somebody do this once or it actually happens more than you then you might think and that you just you take the thing out of the vise and you go ah god I forgot the counter sink it or I forgot to you know whatever it is right so just take a deep breath think about it for a second and go yeah I'm done pull it out of the vise and you're good to go and because sometimes things are really really hard to get back in the vise exactly where you had them before so alright let's get going I will get this other side and we'll swap the setup and we'll get it all cut out [Music] [Music] [Music] [Applause] [Music] [Applause] [Music] let's check it read the darn thing a couple of tents I'm not too worried about that this is just to get it close to start with so I don't have to grind so much of the case hardening off when when it comes back to me treat [Applause] [Laughter] [Applause] [Applause] [Applause] [Music] [Music] [Music] [Music] the kind of the weld assembly here how we're gonna put this together I got some spacers underneath here to centralize the the tube in this that's kinda how that's gonna go together they're flush of that end and then you know I kind of want the tube in the center of this this plate here so I played around with the height of those spacers under there to get it in the middle yeah this should get the ends nice and even DUP okay let me clamp it this way and then we put a few welds in there it doesn't need to be welded continuously you just have to hold it together you know permanently obviously but and it has to survive the the carburization process too so we want pretty good welds on there and it's all steel so it should expand and contract at the same rate so there's no nothin that yeah theoretically nothing that wants to tear it apart so what do you say we go weld this thing I got to do a little prep here V this out a little bit and then I think we're ready for some welding all right so I got the welding done you can see this did a couple on the sides there ends here it's still hot here little more on these sides and then on the bottom all the way across on the bottom so it's looking pretty good you know when you well do you want to make try to minimize distortion so I'm still looking pretty good here and on that end and will surface these will just skim these until they clean up and and then this will go out for go out for heat treat so it's glowing right now so we'll just let it sit for a while and we'll do a little bit of cleanup machining on that we're doing a little truing here so I've got this in the vise and this is a tiny little angle again in it under there that tight I've shimmed it up I measured the offset from where these pads nominally sit on the on the surface plate and I needed to tip this a little bit so I don't want to take excessive uneven amounts off of those so I want to get it as close to kind of square sitting with these just slightly tension uniformly pay attention here and then I can take out the last little bit with the with the flexors there so but it's you know it's still got to go to heat treat and then we got to grind it but I wanted kind of nominally as close as I can get it to start with so hopefully we won't have to grind a ton I wouldn't want to grind this my job as I guess what [Applause] let's check our square here all right looks pretty good this is this is kind of what we're making here but a bigger version of that so let's see what we got now not bad okay so no seven-tenths something like that 7:10 it's leaning that way okay that's pretty good so we'll make the other side parallel with this just machining and this is probably this is more than close enough for heat treat and then you know I'm not sure what's going to happen when we heat treat it how much it's going to move around or break or whatever but we'll find out so let me do the other side and I think I'll dust the top off to get rid of that weld and Bob's your uncle [Applause] you can see the welds there so the filler material is just slightly different than the base material it's rich or an alloy so it ends up being a little bit harder than the than the base material so a little bit stronger but it machines a little different like this see there [Music] [Music] [Music] [Music] [Music] that's right off the grinder and I was plowing about three thousandths of an inch that was my depth of cut for traversing across her I just want to get a basic geometry before I send it up for heat treat then we can check it when it comes back and see how much this moves around during the carburization process it's a little bit of an interesting setup here I want to dust these these side rails off while I got it while I got to go in here and they were a bit out of if if this sits directly on those the sides are out of square - it actually a fair amount so I'm just I've got one of my fresh ground sides up against the angle plate here and we're clamped up so we're gonna dust this off then I can flip it over normal on the chuck and dust the other side parallel to that but just do it now kind of get it get it close and then we'll see how it how it comes out after heat treat [Music] catchin it now [Music] I'm not too worried about heat buildup in this situation [Music] there's a pretty good mass there in they kind of straighten out the world here hopefully I can reach the other side [Music] that we implant them hit [Music] alright this I didn't harder [Music] definitely [Music] [Music] put a little cooling on that because it's a pretty big [Music] [Applause] [Applause] [Applause]

Channel: oxtoolco

Views: 290,783

Keywords: Taft Peirce, Taft Pierce, Grinding, Surface grinding, Toolmaking, Master square, Hermann Schmidt, Cylinder square, Metrology, Perpendiculairity, Squareness comparator, CAD, Sine bar, Sine plate, TIG welding, Fabricated square, Carburized, Carburization, Heat treat, Truss, Pratt Whitney, flexure

Id: G6amOIsBzVg

Length: 28min 10sec (1690 seconds)

Published: Mon Sep 11 2017

Reddit Comments

[u/specialk45]

"Quantifies their agree-ance with perpendicularity, or their lack of agree-ance with perpendicularly." That's one way to put it.

[u/Mitoshi]

What are these squares used for?