FreeCad Tutorial. How to use Datum Planes, Datum Lines in Multi Body Modeling

this is kansas welcome back to the channel for another free cat tutorial you may have come across a situation where more than one body is needed to create a cad model or you need to refer a face on a previous body to generate a sketch for the next body in this tutorial i'm going to demonstrate how to generate datum planes and datum lines and use them to create an object in multi-body environment first thing i'm going to create is a new model so i'm in the part design workbench so i'm going to create a new one so we have this as unnamed that's fine we can go with that now [Applause] we'll create a body and then we're going to create a sketch in this body so i'm going to start creating a sketch in x y plane okay so i'm in this x y plane now you can as you can see uh x and y plane and i can create a 2d sketch so let's start with the slot here doesn't matter um the size of this i'm going to escape out and drag this guy out here we'll put some constraints around this uh just to be uh you know consistent with modeling practice so let's put some constrain it's is yeah that's fine i'm just going to create some quick constraints here okay you can follow me as i do this and since um this tutorial will involve a second body i want to create few um circles inside this main body okay so um seems like i want to increase the length of this guy and maybe drag this one to the size okay and then put a another slot in between these two circles um i'll keep putting some more constraints on this guy [Music] i mean you can you know follow along with this i'm not creating this you know to a precise set of dimensions uh as you can see but when you use your modeling you know you you want to create it in a precise set of dimensions okay um this i'm going to pick this guy and and the reason why i'm going fast is because this is not directly relevant to [Music] the topic we are going to discuss here but you know since you can follow along and you know pick some you know some sketcher skills as well so that's why i'm doing this and then putting a couple of more dimensions here okay then i think i need to somehow give some relative dimension between these two so this block will be constrained and so it's pretty much constrained now because uh how do i know because everything turned green so that's what means it is fully the body is fully constrained or the sketch is fully constrained okay now what i can do is um pad this one sketch let's see i'll give a thickness of 1.2 inches and now this body is um you have certain thickness to it so next thing i want to do is i want to move this body away from this x y and xc plane currently the body is kind of aligned with this um and i want to do that because that way this will be in a kind of a neutral zone and that illustrates my point uh clearly because when you create a uh you know a body it could be somewhere in a in in arbitrary space okay so what i'm going to do is just going to transform this body to a arbitrary location okay i'm not going to give you any dimensions this is just to illustrate the the point that i'm trying to make here so let's go and close that now it's in a arbitrary location okay so next thing is i'm trying to go and create a body that is aligned with this face okay so i'm going to create the second body so this is called body 0 0 1 and now uh let's see which this whether which way this body is active as as you can see how do you know that uh you when you uh you know look at that there's like a white box around it that's mean that body is active so now what i want to do is to create a plane along this face that the plane that is highlighted in yellow okay how do i do that so one thing i can do is let's let's try this one let's just pick on this phase and see if i can create a plane that did not work and you might ask yourself why it did not do that okay now the simple reason why it did not do that is because you are trying to create a datum plane on body one but the face you are picking is on main body and that's the reason okay and so how do we get around that now if i go and activate this guy let's say if i activate this body and then pick on this face and then create a datum it creates that datum without an issue because it is it is actually that plane is created within this active body and that face belongs to that body okay keep that in mind because that confuses a lot of people that hey why can't i create a a plane or a datum plane in the second body by picking on the first one and you can't do that in free cap okay now how do i get around that problem okay so the the simple way to get around that problem is you go and activate the body that you want to create that datum plane by double clicking that okay by the way i have a tutorial i'm going to put a link to that tutorial where i'm talking about this active bodies that overall tree structure of the pre-cad and that would be a very useful tutorial so i'll put a link to this in this tutorial for that video you can go and watch it and more learn more on the you know model tree okay now getting back to the uh discussion we are having so i have activated the body one now there are simple thing you have to do is you have to somehow create a binder okay from this body to this body there should be some kind of a binder so the way you do that is click on that face and this green guy which is called the sub object shape binder we call it sub shape binder you click on that and now if you expand this you will see a binder surface created it's it's more like a you know when you have a multi-body model you are creating a reference phase from this body connecting to this one i have a couple of tutorials on this binder and the shape binder so you probably want to go and look at them i will put a link to that as well in this in the description now uh the simplest thing to do here is in order to create this uh datum plane just pick on this and click on this datum plane and it will be aligned with the uh bind the surface okay now you might run into some issues uh like you know for instance i can show you here then if i activate this body and now if i click on this surface sometimes you will click pick actually you will be picking the surface behind it which will not work okay so that's what happened it did not pick the binder surface so the best thing is for you to do is here uh i'm going to go back here is to deactivate this body pick on this binder surface then create this plane now in this case you know there's another situation where you run into it did not pick this it's glitching the pre-cad what you can do is you know delete this there's no reference now and then you put a reference by clicking on this binder surface okay now that is created now this data plane um is kind of a it's not fully covering this body i like to have it fully covering this body uh it's not absolutely necessary so what i'm going to do is to expand this guy it has this fear this datum plane has its own coordinate system i have a video that explains more on this datum planes as well i will put a link to that tutorial uh go and watch that so uh what i'm going to do is i'm using simply going to extend it in x direction until this started extending okay now it started extending it fully covering the body so i'm all good here and i'm going to get out of it this is still saying it needs recomputing so i'm going to recompute that and now it works so we got a plane that is aligned with the face i wanted now i want to create two datum lines along this um face okay now i'm going to say i'm going to deactivate the body as well as the date of the plane now uh this is the datum line i want to create datum lines one going vertically dividing this edge and the other one dividing this edge which is the datum line is going horizontally okay now let's see what the best way to do that so i'm going to pick this edge this is just to demonstrate how to create datum planes okay now yeah you can do that uh you know once you select a age and you click on the datum plane it will align that datum line with respect to that edge okay let's say i don't want that so just just to demonstrate okay now maybe i pick this guy and pick this one yeah that's another way to do it i still don't need it i'm gonna say delete it now you could do another way to do that is you know go here and through two points and pick that one and that's another way to do that but still this is not what i want so i'm going to exit out of that and then delete that still we haven't found a datum line the way i want to create so i'm going to go back and create the line and then line should be somewhere here and there are several options okay now some of these options are kind of meaningless but they appear but there is one thing that is useful is is this first principle axis second and third now before you're picking anything if you just pick on this binder face see what happens it put the datum line right at the center going through the plane and this is called the first principle axis so enough the if you know a little bit of um you know math or vectors you will have on a planar surface you will have three principal axes one is going through the plane right at the center the other one a plane or a principal axis dividing that plane and then the other one is the third principal axis is dividing the plane in the other direction okay so if i scroll through this it keep moving from one principle access to the other and then you know you can scroll around and see how which direction you want i let's say i want second principle access i want this line which is dividing this is exactly what i want so i'm going to say okay and there's a that first datum plane i created and then same way you can create the second datum line okay and this time i'm going to pick the third principle axis i'm good with that i'm saying say okay you know reason for this tutorial as i mentioned earlier is you will when you start modeling in freecad you will run into this situation many times where you have to create datum lines datum planes on a certain surface to expand your model so this is going to be a very useful tutorial i can guarantee it okay now since we already have this is created so i'm going to use this fail datum and create a sketch on that datum and that's the reason why we created all this okay so we're going to pick on this and then say okay i'm going to create a sketch here it will automatically orient that to face that sketch okay now this you will see that okay i have a prior slight problem here because of this body obstructing the view what all you have to do is to go and click this edit mode switch that will kind of cut a section so that you can see through okay so you can see it now your your datum lines are fully visible okay now you can start creating your next sketch so i'm going to do here is start drawing couple of maybe i'll start with the polyline uh let's see i'm going crazy so i'm keep creating this um [Music] kind of a arbitrary section let's see i think i'm move this around because there are no dimensions associated with it so i can move it approximately the size i wanted um so you can put some more constraint i'm going to put a verticals constraint here so this is all good this has a vertical constraint this has vertical because this has horizontal constraints already and then i can put some dimensions um as well uh let's put a dimension let's see around the sky yeah as i'm going to put some constraints um just to kind of give you some flavor of how you constrain these for this tutorial it's not required but let's do that now one thing might be useful here is these two datums are not selectable right now you cannot select them so the way to do that is this edge linked uh kind of external geometry link okay so this is called the external geometry linker you can go and pick that guy now it's active maybe it's not picking it okay what you need to do is key here and pick this so now it's created a kind of a copy into the sketch now you can pick them so if i want to put a constraint all i need is to click on that now it is kind of a try to align this now i have multiple tutorials describing these sketches you can you know watch i mean if you subscribe you can see my videos and then you can start you know watching those videos that will give you more in-depth understanding of how you give a sketch how do you constrain it all that good stuff is on those videos so i'm not going to spend too much time on this uh on this tutorial just about enough time so that i can kind of pass along the uh this uh the useful information that is more pertinent to this tutorial okay still it's not constrained um i can put some more stuff here and then yeah we need to put another one here as well so it's coming along but i'm going to maybe i'm going to stop right here there may be a few more constraints you need it but you know for this tutorial purpose it's not really required so i have this second sketch created now using this sketch what i'm going to do is i'm going to pad this guy now when i'm padding this i'm going to do two-dimensional direction so it's going to go this direction as well at this direction this is i'm going to let's say make it one inch in one direction and see whether that's maybe that's not enough let's do two inches the reason why i want to have two inches i want to be sure this body kind of a covers or can encapsulate the entire this uh this body the first body okay and this guy will i think you might need like three inches here a little bit more okay so that she took care of that now one thing i need to do here is actually go back to this sketch and i might have to expand one of these dimensions okay so sorry i need to go back to the sketch and see through maybe i need to give a little bit 6.5 inches or maybe a little bit more i want to get it beyond this body the same thing on this side as well i think yeah it's beyond this body so that should be fine okay so we got actually it's not so let's go back okay got that now um all i need to do is um use this which is the a boolean operation let me go back and show you what this is called the boolean operation um and i need to recompute it so this is the boolean operation with two or more bodies so i'm going to i've already picked one body uh so i'm going to say okay pick this this guy and body it might yeah so if it is doesn't do first time uh you can pick on different uh surface and it should appear here inside this box now what i want is common so this cr pretty much created the bracket we want to create okay now of course you can go back to your you know sketches adjust few things and make it look you know if you want to increase the thickness here you can go back to these sketches and do that but pretty much this is a bracket we wanted to create now i can go back to this cage this cage and i mean i can you know increase this thickness uh seems like hey this is way too thin so i'm going to say four i'm gonna oh yeah maybe 0.24.4 is too much 0.35 and let's see yeah that should be fine now you can see that it is got a little bit beefier okay so you can play around with this uh sketch to get the bracket you want okay now the key concept of this tutorial is to demonstrate how to use datum planes and datum lines in multi-body modeling how to use them effectively uh so that you get you know you you will find this easier when you start building models in freecad so that's the purpose of this tutorial hope you learned something new uh please leave some comments uh and if you like it please give us a thumbs up and subscribe thank you

Channel: CADZiS

Views: 937

Keywords: Freecad;, FreeCad, Constraints, Geometric Constraints, Sketcher, Modeling, 3D Modeling, 3D Printing, cell phone, Planes, sweeping, Draft, Drafting, draft workbench, datum line, datum plane, snap, draft creation tool, Model Tree, Tree View, Standard Part, Part Workbench, Part Design workbench, cumulative single solid, Carbon copy, cut and paste in freecad, shape binder, shapebinder, Subshapebinder, Binder, Green binder, sub shape binder

Id: XOkPpmZc7es

Length: 27min 4sec (1624 seconds)

Published: Thu Oct 07 2021