Basic square to round triangulation

hey guys uh just wanted to do a little drafting lesson here for you um hopefully this one's a little easier to follow along than the one i did before i'm actually gonna do uh well attempt to drop this out on paper um to give you guys a step by step so uh i have a squared around here that's gonna be six inch round on top eight inches tall and then it's a 10 by 10 square bottom um it's on center both ways um so the very first step you need to do is make a plan view drawing of this so i'm just going to start off by drawing a plan view in this corner so one two three four five six ten so it's going to be freehand but i got grid paper here so this should uh help me keep it pretty pretty straight and easy to see all right and then there's our center um okay so now i'm going to use a compass here to make a the six inch round part so i've already got it preset uh hopefully this shows up okay i'm doing a full plan view here just just so you guys see uh what it would look like from the top of this fitting okay and then using the radius that i got to draw that circle if i go to the center points of the circle i can use that same radius to divide it into equal spaces all the way around um i'm just gonna split this fitting in half because um laying out a triangle like this you want to have two half patterns i only need a quarter of it to actually lay it out because uh this corner this corner this corner and this corner all exactly the same but for the ease of this layout i'm going to show you the full half pattern here so i'm just going to darken up these points so they're easier to see um so each one of these points now gets drawn back to the corner so from this corner here i'm going to go right to the center and then to this division this division and then all the way to the center here then i'm going to repeat that in this corner okay now you can see this corner and this corner exactly the same i'm just going to darken up the circle so there we have a half pattern in the plan view so the next thing i'm going to do is label it i'm going to do the the the square parts with letters so i'm going to go a b c d and my circle part i'm going to label numbers so we have one two three four five six seven um all right so that's step number one making a plan view that's labeled and all to scale now to lay out this pattern um it's it's basically triangulation the the definition of it is having two known points to find a third unknown point so in this view here i can have a distance from this one view so i have a known length here but i need an unknown length in another view as well so i can find the fir the third length so if this squared around is eight inches tall i need to represent that in a true length triangle so if i just make a true length triangle here that's eight inches tall so we got one two three four five six seven eight so it's eight inches tall from here to here eight inches uh and then i'm gonna just do an arbitrary length out this way so this is where i'm going to be plotting measurements from here so i can actually make a hypotenuse which is going to give me that third length or the true length so if i take these measurements here so from this corner to the number one if i measure that and then transfer it over to the baseline here starting the bottom and moving it there um then that hypotenuse becomes the true length for this b1 line so again take a measurement of b1 put it on the baseline here and then from the top of that eight inches down to the baseline that's going to be a true length now with a squared around on center there should be a lot of lengths that actually end up being the same because i freehand this might not translate super well but uh b1 and b4 are going to be the same which means c4 and c7 are also the same so i can actually label that on here so this first line i did is going to be b1 b4 c4 and c7 now the next one i'm going to transfer over is from the corner here on b to 2 and i'm going to put that on the baseline here and again because it's on center b2 b3 c4 or sorry c5 and c6 are all the same so when i transfer them over on that true line triangle they're all gonna be the same length so b two b three c five c oops c6 those are all the same at this point now there's two more measurements i need to put on there and that's gonna be my a to one and d to 7 because in this view they're not true lengths either in the plan view here the only thing that is a true length is a to b b to c and c to d because they're perpendicular to my point of view so i need to plot these out so i can get a hypotenuse to make it true length so if i take that measurement there a1 and d7 are going to be the same so plot them on the baseline here a1 and d7 all right now i have all my uh plan plan view uh lengths and then if i have my elevation view uh height here i can get a hypotenuse for each one of these and make it true length so the way to actually lay this out uh the pattern out as a half pattern i'm going to start with the middle of the pattern which is right here b c to four that's the very first triangle i'm going to lay out so then that's basically what triangulation is finding triangles and then drawing them in a true length form so i'm just going to start with the bc and if imagine if i was standing in the middle looking this direction for it to be an inside pattern b would be on my left c would be on my right just the way i'm looking at it now so if i start taking a measurement here of bc because it's a true length and i'm just going to plot it right here on the bottom b to c so this point to this point there's my b here's my c and i'm going to connect those with the line now the next point here is four right to close this triangle in so b4 and c4 and if you remember when i first plotted them out they're both in this column here this this same length so if i go from the top of my true length triangle now and take this measurement right here that hypotenuse of that triangle is a true length so now i'm going to go from my b to number four and then my c to number four so now this point here becomes number four and if i draw lines to connect them there is that triangle in true length form this is actually what it's going to be in reality so this triangle from this view is that triangle right there um so now i'm going to go i'm going to just start on my b side here actually what i do on this side is i'm also going to copy on this side because the lengths are the same so i'm going to take my my b3 and my c5 so and those are both from this next column here so from the top take this measurement so b five and c oh sorry that was b3 and c5 right now uh the next thing i need to do is go from four to three and from four to five so i'm just going to take a cord length here from this plan view make sure that they're somewhat even so now this is going four to three and four to five i didn't quite swing those long enough a point there and that point there so we have three and five um it's if you note i've actually got two uh compasses set up here one that's short and i'm just going to leave this one for my my cord lengths on this plan view just preset so all i have to do is step them off now i don't have to keep adjusting it and my larger one here where i can transfer these measurements pretty easily now if you remember my next ones here now are going to be bead of 2 and c to 6 and if you remember 3 5 2 and 6 are all the same length so i don't really need to change anything here they're still coming from this point here so now and that arc i've drawn if i just extend it out a little bit it should be enough to cover that so now i'm going to go from three to two and then from five to six so first from three to two and then from five to six six two and now finally i need the b to 1 and c to 7. so that's uh again going back to this longer length here b1 and c7 are in the very last column so i'm going to take that hypotenuse there and b1 c7 i use my small compass because it's already got those preset one and c7 number one seven so now we have the full all the numbers that are in the round part are all done here so now uh i still need to finish these wings so i'm just gonna connect these lines so you guys can see what we've done so far right so one two three four one two three four we have all the same lines matched in here i can actually connect my round part but now i need to go from from c to d and b to a and if you remember these are true lengths because they're perpendicular to my point of view so i just need to take the measurement here c to d so c to d remember i'm going from c though so it's at the bottom here c to d and b to a is also the same measurement so i'm going to go b to a and now i need to go from one down to a and then also seven down to d so because it's going from seven to d one to a so those are on the last part here on my true length triangle the last two measurements so if i take this hypotenuse and i'm going to go from seven to d and one to a d a i have completed this fitting well the half pattern anyway so one two three big triangles and then one two three four five six two three four five six little triangles uh and that is a completed half pattern uh the way to double check to make sure it's right this should be a 90 degree corner here and here um and this half of the pattern is going to look exactly the same as this so all i would need to do is flip this over and trace it and then i have two half patterns um now if this was a squared around that was off center in any way i would definitely have to do at least a half pattern uh and if it's off center in both ways like if the circle was down here i would have to draw a full uh plan view and there'd be a lot more numbering and transferring but it's the exact same process just taking dimensions or measurements from this view putting them on a true length triangle and then laying it out the way i've showed you and that's basically it you

Channel: Sheet metal layout school

Views: 108,540

Keywords:

Id: 8M5jkUcSyhI

Length: 16min 51sec (1011 seconds)

Published: Tue Nov 17 2020