 Okay, let's get started. As I mentioned before, a lot of these pages are from previous years, nice pictures, stuff like that that I just throw in because I think they help make the point. We were working on fasteners. We were working on fat butt's lusmit dur. I don't know, don't do that again. We were working on the fact that sometimes when you bolt something like an angle, the load had to come down out of the top leg and go down in the bottom leg and you lost a part of the angle, thereby making it less efficient. This is for staggered fasteners and how you handle the loads in a plate or an angle under those conditions. We mentioned that the length of the line, should the tear line decide it is too hard to fail it across here, it's just easier to go ahead and skip over to the next hole even though it's longer. We mentioned that there were tensile stresses and shearing stresses. You would normally think, let's just take this total length across here and find this squared plus that squared, take a square root, find that length. How much ever longer the hypoteness is other than the leg, you just add that amount, you'd be okay. Physically that's true. Structurally it's not true. What we've really found is if you go from this hole, don't go straight across but move over to this hole. The previous length of this line is increased by s squared over 4g. This was our spacing and this was our gauge like the gauge of a railroad that runs down the tracks in the direction of the load. So this original length leg of the triangle is not that much longer but it's that much longer and that works out really close for the structural strength and it includes the fact that it is longer but also that different kinds of stresses are acting on the plane. Other than just nice old tensile stresses. There's several reasons why you would do slanted staggered fasteners. Number one, if you put them side by side you do destroy two holes worth of strength and you don't pick up any extra length so you may want a little extra strength. Sometimes the member itself is slanted with respect to what you're connecting it to so when the load comes down it sees no holes, no holes, one hole, maybe one hole in that hole and so on. There's your s, there's your g. Old notes, gross area for a plate, just the two dimensions of the plate, net, two dimensions minus the number of holes that you cross as you go through a tear line times the diameter of the hole which is the diameter of the bolt plus the sixteenth plus the sixteenth times the thickness of the plate. Sometimes that's not the whole story. For plates this is good but for angles that are bolted only on one leg and have an outstanding unconnected element you will have to reduce it by a reduction factor. Those are listed for different cases. Down with the hole, down with the bolt plus the sixteenth for fit, damage, effective area in this region right here you do get a stress, down in here load over area gross, down in this region you get load over area net and it's increased by you or the load is decreased by you, take your choice which way you work it. There's your net area. And how bolts really work, here's a plate, put 200 kips on the plate, I'll tell you now that I tested these bolts around 80 kips they get a little deformed but they'll go on up into the yield range and keep picking up load at 100 kips they're just pretty much trash. So out of 200 kips the first load hits the first two bolts and 80 kips on each bolt drops out then that leaves 80, 80 is 160 that leaves 40 kips in this region right here and you say well why aren't they all 80s because until these bolts fail a little bit allowing this plate to stretch see if this if this bolt doesn't do a little bit of this then the plate behind it hasn't moved so until it has a little bend in it no load gets on through because the plate isn't allowed to move and so you don't get any load but at 80 kips they're deformed pretty enough that the plate right here can stretch and then about 20 kips comes out these bolts and then you get no bolts on no plate no force increase it to about 400 kips the 80 runs on up to about 90 each about 70 each comes out here about 30 makes it down into this pair of bolts and about 10 make it down into that pair of bolts and these bolts here say huh nothing down there nothing made it because the plate hasn't stretched down in that region enough for those bolts to pick up some load here's 580 kips a hundred and I see these bolts have gone plastic they have deformed like that you know they they had a hundred in them when they only deformed maybe this much and then they held a hundred when they deformed that much and they held a hundred when they deformed that much so they got 100 160 2010 here's 760 kip supplied 100 100 100 these have all failed fully plasticly but they're still holding the load 50 got down to here 30 got down to here and finally which is where we design it all the bolts are equally loaded now you can take that to extremes if you took this down here for 40 feet I don't think there's any way it would really work because these bolts would hold 80 till they went up into the ultimate range and then they'd break before this bolt down here even knew what was going on so you'll find in the specifications you will pay a penalty if your bolted connection is too long and they're taking that into account here's a plate it's got 900 kips on it at ultimate load there will be 123456789 what gee that's convenient nine bolts and therefore a hundred kips will fall off of each bolt just like water running down a trough this hole is big enough to let a hundred gallons a minute out you're putting 900 gallons a minute into the trough when I ask you what is the flow right here you would say 900 gallons a minute if I ask you for the flow of water at this point in the trough you'd say well that trough has a hole in it and it let out a hundred gallons a minute so how much gallons a minute is left 800 gallons a minute and that's how much load is left so there's 800 kips going to flow across this pair of bolts take out 200 from 900 it's going to leave you 600 kips of load at this row of bolts and on the last row of bolts you'll have 300 kips trying to break across that line now if you study a break line that goes across here you'll have to reduce the load trying to break across those two bolts by whatever has been removed before it if you try and find out might this break across here well then you'll find the full 900 kips of load is in there and the 900 will try and break across here across here across here and back across three holes but of course you do pick up some extra s squared over 4g two times because you have two slant lines this is your gauge running down the axis this is your spacing so there's an equation for it but I don't think you need it load is equal to the number of bolts remaining on that line and further to the right divided by a total number of bolts times how much you put on there I think it makes a lot more sense just to look at it and see yes sir if it if you make it out of glass yes but we don't do that very often you can try it because steel is so ductile the bolt can withstand I'll show you some pictures later on massive amounts of deformation where it looks like the thing should have broken long ago and the truth of the matter is it's just right about here and not let go of its law didn't break they look like this all the time once you take them out of there and they're not broken you say they sure scared the dickens out of everybody life is tough don't go in our buildings if you don't want that to maybe happen but you won't die here is some or the same has some reasons for you the load is coming in can't get in this little piece it's lost to you you will be a measure of x bar divided by L 1 minus x bar over L here you had a welded on the sides you have the same problem even though the wells can get in there you're losing this piece if the wells are long enough we can live with it here's where you welded on the two sides of the plate you didn't think you're going to lose anything you don't have any outstanding elements unconnected well you really do this little piece of the plate itself the stresses had to go around to get into the weld you put a weld across the end hundred percent efficiency everybody's got a path to transfer the load from the top plate to the bottom plate if you will just across the end of an angle that's really tough and they just say look suck it up where you don't even get an angle you just get the plate that's down there on the bottom of the cross sectional area of that would be reduced down to the thickness of the angle times the leg length that's welded to the plate here's a nice long weld plenty of time for the loads to get out you as a one here it's worse therefore use less than one here it's horrible look at these poor people trying to get out this little bitty exit use zero now the Segui and I and a lot of people like to they work these problems they like to come up to the hold and if they see a slanted line coming up they say well what I'll do is I'll subtract the s squared over 4g from the whole dimension when I when I put it in the equation and I'll just go ahead and use the distance across here but I just won't take off as much hole so in other words basically I'll still have this dimension minus one hole and because of the slanted line coming up I'll make this hole a little smaller that drives me crazy I can't remember all that nonsense and but some of the calculations of the book are done that way you'll see the calculations are the same I highly recommend you just find the gross area of whatever you're talking about out take off every hole along the tear line 100% and if any of the tear lines are slanted then add to the strength the cross sectional area an s squared over 4g to take care of the fact that this is longer than this you've already taken into account this by using the gross area you turn the gross area into a net area by taking off two holes and then you add the added strength due to the slanted line s squared over 4g now that's not an area that's a length that of course then has to be multiplied by how thick the plate is your choice but I just I just can't keep that other thing straight because I come up I see two holes and so do I do that twice which hole do I do it for either hole I don't know we want you to compute the smallest net area for a plate shown in figure 315 on the next page and I put a load on there I just like loads on things I'll put 1100 kip 1 2 3 4 5 6 7 8 9 10 11 I wonder why he says the effective hole diameter is one inch bolt plus a sixteenth plus a sixteenth then the calculations for line a b d e here are your failures a b d e is possible a b reach out and touch someone c d e is possible something unnumbered c something and g is possible I was getting less and less likely because the loads being reduced as we go down the plate here's a possibility from there to there to there way over to there and I'm not doing that there's no way that's going to fail like that either going to fail straight across here if this is pretty far back or it's going to fail right across here if this is an extra hole but you get some added strength or you know it's well it can't fail across here that's only one hole it'd rather fail across two holes so there's not too many things you have to check first you're going to check alpha baker dog edward alpha baker dog edward straight across it's 16 inches across 5 10 left of 13 it is 16 inches across he'll subtract out two holes of one and a quarter inch width notice we're only talking about the length of a line here that's 13.75 inches across the plate therefore the net area is 13.75 the plate is three quarters of an inch thick gives you 10.31 square inches of steel if it fails across a b d e if on the other hand it fails across a b c d e a b c d e then we have a length of 16 across we'll subtract out three 1.125 inch holes and we will add two slanted lines each line having an s squared over 4g there's your two slant lines there's your spacing along the railroad tracks divided by four here is your gauge parallel to across and parallel to the railroad tracks how far it is between the wheels so it's 13 point that's 10.1 and you will be picking the lower of the two other words that's less net area and then that's going to be now that's excuse me that's just this is just the length you can check that's just the length that's 16 inches this is just the length two times spacing squared that's inches squared divided by four times the gauge that's inches inches squared divided by inches is inches this is just the width somebody going to multiply that times t before we're going to be finished or we're not going to have an area so what he found on the previous page was it was 10.30 10 13.75 inches across the plate there he multiplied it times the thickness of the plate there's his 10.31 square inches of steel for the second line he has its 13.52 across the plate that's smaller than he had on the previous page that's why he didn't actually he didn't actually do this calculation he says let me just see how far it is across the plate 13.75 let me see how far it is across the plate 13.52 he says that's the shorter distance across the plate then he multiplies that times the thickness to get the area that is his net area how's he going to turn that into an effective area now they're going to multiply it by u what is u for a bolted plate it is one that's correct and so he doesn't have us written down here but that's that's a thought you know every net area is going to have to be multiplied times u even if it's a one before you're finished now this is pretty much what we said about each fastener resists an equal share of the load in this case right here if you had 1100 kips then at this level right here you'd have 1100 kips right at this level you'd have 1100 kips right at this level you'd have 1100 kips because as of yet all the steel to the right of the lines that are shown they're still subjected to the 1100 kip load nobody has yet pulled some loads out the minute you get to this point on the other hand you can't fail across here or anybody downstream without three bolts having pulled out their full share of the load three out of 11 that's that's 100 kips each so the load along this line and anywhere back here till you hit some more holes is going to be 800 kips now if you're talking about an angle then what you can do is just go ahead and flatten it out into the plate from which the angle was made to get your gauges and your spacings it's a lot easier to see the truth of the matter is in an angle i don't yeah here's one drawn in three dimensions uh the the tear line comes down and across or the tear line may come down and across uh here's your spacing here's a problem let's say there's another hole up in here finding if that hole is in that line then there's your gauge right there the distance from here on down to here you say that's kind of hard to see well flatten it out it makes it a lot easier here is a an angle that has been flattened out it is a five by five by half inch angle if you look on page one dash 48 it's on page 60 b in my notes so it's coming up you will find a list of numbers that says when you have five inch legs and you want only one hole put it at three that's the common thing to do if you want two holes look at all these people pulling out their books and think i'm lying i wouldn't lie to you golly he says no you're not lying you're just wrong so much of the time i'm just checking okay if you want two holes on a five inch leg then you'll go at two inches and one and three quarters of an inch now that's there just because they fit the guy can get a wrench on it or the lady can get a wrench on it but it doesn't have to be it's not required it's just good practice unfortunately when the load comes down and has a tendency to break from this bolt to that bolt maybe back to here the full load then i need to know how to add the s squared over 4g for this line which is around the the corner what you can do is basically the gauge length from this bolt here to this bolt here is just three no no no no no no you went too far sorry minus a half of the leg thickness plus here no no no no no you went too far please back up half of the thickness so the gauge length is three plus two minus two halves minus the thickness just that easy to get the gauge on an angle and the spacing of course is right here wherever that spacing is um he's he hadn't shown us so we'll have to find one where he shows us what that spacing is if the plate itself if you're looking at the gross area back in here you'll find that that is a seven and a half inch plate because it goes from here to here which is five and then it goes from here to here which is five um that's interesting oh that's sorry that's um that's a different angle i wanted a different one the area across here the length across here is five inches you went a little too far plus three inches you went a little too far five plus three minus a half seven and a half inches across there here's his problem he has a has a eight by six by a half inch angle if you want to know which is the eight and which is the six you could go look up why he picked these numbers that's in the six inch leg and why he picked these numbers those are in the eight inch leg this has got staggered fasteners therefore seven eighths inch diameter bolts so the whole size is one inch from the dimension tables he says you can get the gross area you'll find that on page one dash 42 six point eight square inches if you drill holes in it that's your problem i gave you six point eight square inches when i delivered it to you the net area online a b d f all right here's the end view here's the top view here the thing is flattened out he says the gauge length on this one is four and a quarter let's see if i like that two and a quarter plus three that's uh five and a quarter inches three four five minus it's a half that's right four and three quarters inches so we'll check out line a b d f a b d f goes straight across you'll take the gross area you subtract two holes no slants for you they'll take the gross area each hole has got a one inch loss of steel across the plate and it's a half inch thick be nice if you put units on these so you really see this is square inches this is a half inch thick angle this is a one inch diameter hole yes sir there it is that's why it's a one it's correct and then there are two of them as you go across the angle five point eight square inches if you get a net area someplace smaller someplace else then we will not even need this calculation a b c e j a b c e j well he's skipping one he probably ought to be checking a b c d e but i can live with it he says look i can't check them all i show them how to check a couple they ought to be able to figure that one out on their own i say okay how many slant lines would you have if you went a b c d e we'd have two slants an s squared over four g for that one and an s squared over four g for that one but doing the one he wants to do i'm going to give you the gross area straight across i am going to subtract one two three holes let's count them up there's one of them there's two of them there's he subtracted three holes then i get to add an s squared over four g term where the spacing is one and a half and the gauge is two and a half there's your one and a half there's your two and a half there's your s squared there's your four g well what is this man he's doing it the wrong way oh he's doing it that funky way see the plus plus s squared over four g for that slant line right there and uh and since he's calculating straight across he only gets one you and i were talking about getting two but you know he's not checking that line he's checking a b c e g there's his plus s squared over four g question i see it in your face something doesn't make sense maybe not maybe you just had a little heartburn there questions he says pretty obvious pretty simple pretty straightforward it is but until you kind of digest it yes sir okay see you see this number right here it's a distance across the plate to turn that into an area he has to multiply it times the thickness everybody has to have a thickness on it that's correct see because this is the length across a hole and this is an added slant line distance both of those are at some time or another got to be multiplied times a thickness to turn the length into an area and that'll be a very common thing you forget to do on a quiz you're so happy you got the s squared over four g you forget to put a t on it yes sir uh then he's right in your wrong the question was what if you check a line and uh you don't get the same answer the book gets then you're wrong and the reason you're wrong is because there was a worse line somewhere else that he checked the reason was he probably forgot it in class a couple of times and then some student says looks like that other line would be worse and he did it and uh oh and so in his book he wrote just that line because I don't know I really don't know if it's better to go across here or better to go across here generally speaking much further back's not going to be worse although that is picking up an extra hole going like this I'd have to check them all now on an exam you know you're not going to have to check them all I want to know can you check any of them now if you can check any of them you know I would say what is the strength across line a b x m p you say nonsense it couldn't possibly happen well that's not the question the question is can you do it okay now these are the same thing laid out flat with the gauge numbers written a little bigger and more clearly here's line a b c e j g and all the calculations in the s squared over four g's multiplied by t so take a look at any of these pages that are you know just complementary to the previous stuff here's the page I told you that the angles would give you the place to put the holes once you get down to a four inch leg you can't put two holes in it so there's only a g1 in a six inch leg you have the choice of one hole or two holes just an extension of the previous problem page 60 page 61 all right now oh that's right sorry I've entirely forgot about that since he's checking this failure line right here he no longer has 100 kips of load on there he no longer has the load p since he's studying behind that bolt when that bolt fully took out some load that load removed one two three four five six seven eight nine ten one out of ten bolts it removed ten percent of the load now generally speaking I you know I really don't want to go do all this calculation for that line and this line and that line and this line and that line it would be nicer if I could just get the net area and write it down and I was getting ready to write in fact I think I we did write down this net area but if you want to be able to compare it with a previous net area that you calculated somehow you're going to have to admit to me that the load that gets to that line is not full load it's only nine tenths of the load because you passed up one tenth of the bolts they already took that load out and so what everybody does is rather than looking rather than doing all the calculations with this net area and doing all the calculations with that net area they just say look you know what this net net area here is I say yeah I just wrote it down he says you're wrong it's 10 nights bigger than you have written down what how can that be let me check my calculations he waits and grins and lets me read I said no you're wrong I said the net area across that thing right there really is 5.413 square inches he says it's not effectively that much he says because it's only hit by nine tenths as much load you need to take that area and multiply it times 10 nights before you can compare it with this area on this line now that may may have your head reeling you may say got a brain I don't know where you are at this yet but it's it makes sense in other words the area here calculated as net was impacted by the full load the area down in here was a net area but it only got hit by nine tenths as much load so I'm going to multiply that area times 10 nights so I can compare it to see if this guy wins or this lady wins and that's what's going on on this page here so this thing should be multiplied by 10 nights to obtain a net area that can be compared with other lines that are having to resist the full load therefore this is how much net area it has then he says a b c d e g good heavens where is that a b c oh that's the one I thought might be interesting a b c d e g you're gonna have one two three slant lines so you're gonna take the gross area you're going to subtract one two three four whole widths times t you're going to add a s squared over 4g for this one times t you're going to add a s squared over 4g for that one you're going to add an s squared over 4g for that one times t and I'll tell you the net area incidentally the net area uh well anyway let me see so wherever we got that we ought to have gross area here's one bolt here's two bolts here's three bolts here's four bolts and there ought to be a thickness times plus s squared over 4g for one of the slants two of the slants three of the slants now those are the net area where's the where's the effective area is this an angle the effective area where's my u where's the effective area where's my u is equal to one minus x bar over l all the connection all of the outstanding elements are connected there are no outstanding unconnected elements connected connected u is equal to one good so then we can go ahead and find out how strong the things is oh there it says right there both legs are connected u is equal to one the effective area is the lower of the two we have two strengths one will be based on fracture and one will be based on yielding based on fracture we have the effective area times ultimate 293 based on gross section yield out in the middle of the member we use only 36 the yield times the full gross area 244 we still don't know who's the winner because one of these guys is really dangerous going to be have to knock down to 0.75 of its value the other gets 0.9 based on fracture 293 times 0.75 220 based on yield 244 times 0.9 give me a break very chance well it wouldn't happen in another hundred years they're both the same you would take the lower of the two the other example five by three by half finding the gauge length is three inches plus one and three quarters minus the thickness of the angle 4.25 inches that's if you have a five by three by half inch angle and put one hole in the long leg if you put two holes in the long leg this is where they go g is two plus 1.75 minus the thickness of the angle that's the gauge quick and easy to calculate wow man what a weenie pop quiz that year here are the tables where all this stuff is coming from remember we used f sub u and f sub y there they are page two dash 48 the other example determine the smallest area for a channel works just like everything else smallest area for the channel will be the gross area then you will take off one hole and have no slant lines then you will check going across two holes and then get a slant line here's your here's your area here's one hole with no slant lines here's your area here's your hole remember now the thickness of a channel is a weird number that comes out of the channel tables thickness of the web there's a hole here's a hole circled here is a minus times a minus one slant line two squared and three two is the spacing there's the spacing here's the gauge three inches now he doesn't carry that on out because now then area nets not area effective so i went ahead and did that he didn't ask for it you shouldn't do it if it's not asked on the quiz usually go to one minus x bar over l this number right here is listed in the channel tables see this on page 62 a and b where we got 62 a here's our channel it is a c 6 by 13 there's the web thickness 0.437 inches next page probably gives you the x bar here is that's that means wrong don't do that one that's x plastic this is the one you want x bar for a 13.514 inches that's where the centroid is that's from there to there so one minus there's your 0.514 inches where did that come from there huh right up here you have the spacing length is from bolt outer bolt outer bolt four twos one two three four twos eight inches that's the length of the connection you must reduce the strength of your calculations by multiplying them times 0.936 to take care of the fact that around the ends of the channel the the loads can't get up into the up into the flanges they have a hard time doing it and so area effective is area net times u you got 0.3.31 times 0.936 this is the area that you will use for area effective we're going to use that in our growth section yield or our net section fracture calculations I don't remember both that's a safe way of doing things fracture only right or you can wear a belt and suspenders but it's probably overkill so this is an effective area for use in rupture calculations around the bolts in the growth section yield end of things you're going to be using the gross area and the yield stress then we have staggered bolts just weird situations we don't do them I think many times a text will include those things in case the prof thinks it's important and doesn't use his book because he didn't have it that's for bolts in the web and in the flanges of s shapes and it's just never just very seldom done here's where I'm getting all this stuff from chapter d design of members for tension 16.1-26 you'll see immediately why I brought it out tensile yielding in the growth section there's the equations Segui gave us that's where he got it from what does he multiply it by 0.9 what is that name what is that thing called there's a strength reduction factor there's many of those but this one in particular is a on which side the load side of the resistance I think I just gave it away yeah it's a resistance factor that's right it's applied to the resistance you already have factors to go with the load 1.4 dead 1.2 dead those kind of things here's your tension rupture f ultimate area effective someplace else you're going to have to tell you how to get area effective from area net he will here's your reduction your fee for fracture there you go effective net area how do you do it well you multiply it times you but now you got to tell me how to do you says well it's in table d31 where the devil is that I don't there it is right there all of these things they refer like spider webs to different things you know and you got to be able to go dig them out because that's all you bring with you to an exam sometimes for bolted splice plates this doesn't work as well as we wish it did and therefore let's say if you're doing a splice plate the area effective can equal to the area net that's bolted plate the bolted plate however no greater than 0.85 area gross why is that said because something fell down to one day and since we don't want it to happen again since we find out we'll let you know but uh no bigger than that for a splice bolted splice plate there are your u factors here is the is this sugary or specs how do you know it specs looks just like sugary why they've got a section number up here 16.1-18 that's the page number came out of section b4 gross area how to calculate it net area how to calculate it time is it I'm having fun yeah I still got time there's that one I was telling you I told you well it is there's some for s shapes and there's some for channels bolted into the flange and the web just I don't think I've ever seen such a thing he's got an example forget it block shear what is block shear well it used to be we bolted an angle to something we didn't have any problem with this but then they started making this nifty steel the old steel was like a seven I don't know how to yield stress of 20 or 22 but as the steel's got stronger and stronger we started using thinner and thinner shapes as we used thinner and thinner shapes fall of a sudden we had these little corners tear out didn't break across the holes and didn't come out break out in here little corner broke off so we said all right we got to do something about that if you'll notice that when this thing pulls you have a shearing stress on this surface and you have a tensile stress on this surface so now that's going to be a kind of a combined item because the shear permitted stress is going to be smaller than the tension permitted or limiting stress as a matter of fact it's six tenths in fact it is so much six tenths we don't even have a name like that we don't have a f yield and shear because it's six tenths of f yield intention and you don't even have a f yield intention symbol in your book all you got is f so why because that's all we have is tension is there what happens when we have shear it's 0.6 of f so why how about ultimate same way it's six tenths of f sub u which is more properly said f sub u intention and six tenths of that is the f sub u and shear see you next time thank you sir yes sir i can't talk to you about i'm gonna be gone for a week okay and then i'll so i'll have all that the assignments to you the money i get back that'll be fine that'll be fine and don't come by my office just put them in here yeah no just say larry larry i went on went on the trip larry has excused this absence they'll know you wouldn't dare write that down if it wasn't true i don't blame you let's just say that i found the effective area right here right gets hit by the full load doesn't it right yeah now then you probably wouldn't check this because the effective area would be the same but if i wanted to compare how strong this section was with respect to that one right do you see how i would first say you know the 600 kips applied here never made it to this section and therefore what i really if i want to compare this section's area with that section's area to see who's worse i really ought to take off two six of the load right because only four sixth gets here yeah what i can do to account for that is multiply this area times six force to compare it with this area that's exactly right see because the it's like holes in a trough yeah the water hadn't made it out of those two yet if it's gonna fail across here you only had one hole sucking water out of the trough so now then across this plane here you have five six is much load so when you calculate the true net area or or or effective area please if you would multiply times six fifths so i can quickly compare it with this area okay a 242 all right that's a good steel i love that steel and it was for a plate so i went over to this table here for plates yeah and i noticed that there was three different strengths for that plate okay with no little symbols there so i was wondering all right let's see let's see what you're talking about so these are shapes these are plates a 242 well these are designated by that i mean i'll tell you what the plate is a 242 for a 242 grade uh have grades on them yeah on this one do we yeah the same ones for that well um that one has lk yeah just this is really plates are the numbers the same 42 46 and 50 yeah they're the same he just figures you'd refer over here and then yeah the plate they fall in uh i guess the cake or the thickness whatever yeah right see the only reason the only reason you have the different things is because of more of the impurities being rolled out so whether it's rolled in a plate or whether it's rolled in an angle this this angle used to be a plate or that whatever it is used to be you know something that was a bar and then they rolled a plate right so yes that's where you get your numbers okay um a couple more questions all right let me just make sure i'm ready to go and then i can get out of the way when the next guy comes in