How do you embed metal in a 3D print? Today we’re going to talk about a part that I built on the Stratasys F370 using ABS material, that captures a metal hex bolt in a 3D printed thumb screw to complement our Origin One sample part. To do this, we will identify the layer to add a pause and remove any support material that could interfere with insertion. I’ll show you the steps to take this file from SOLIDWORKS, to Insight, and then to GrabCAD print!

I used SolidWorks to design a simple thumb screw shape. It’s an extruded cylinder with knurling around the edge and the TriMech logo on the top.

If I turn this view to transparent, you can see the hex bolt head cavity. We’re going to highlight this face right here, so you see the exact layer that we’re going to add a pause in our build. It’s the first layer after this top surface of the bolt head.

In the Insight program, we’re going to delete all the supports that are in this cavity for the hex head. We want to leave room to embed our metal bolt in the 3D printed part.  We’re going to build a tree for it to visualize this feature. We will make a cylinder and a flat plate with enough space for the bolt to go into the build. Later we’ll delete the cylinder. That way we’ll have a hole in the support surface that goes up to the base of this part.

When we hit the pause, will be able to take the bolt, pop it into the part and then continue printing.

Now we’re going to go ahead and take this assembly and export it as a single .STL file, even though they’re not connected. And we’re going to bring that into insight. Now that we have our assembly in Insight using a single .STL  model, we’re going to confirm that our settings are correct. The most important one in this circumstance is that we are using sparse support structures. Those support structures are completely vertical versus the smart support style, which will build with a self-supporting angle. And because we’re going to have a hole through the center for our bolt to go into the part, we want a nice strong base, so that the vertical structure of the sparse support style will be perfect.

Let’s go ahead and slice this part up. You can see the empty hex cavity on the interior. So, the very first thing that we’re going to do is we’re going to locate that first hex slot. And we’re going to go one slice above that, and that will be our layer for the pause. To do that, we’ll go to tool paths, insert pause, select that layer and click okay.

If we look from the side, we see all the layers. You can see exactly where that pause is. It is a highlighted layer when we’re in the insert pause menu. It’s important to note that when you are making multiple copies of a part that has a pause in it, you’re going to want to save two different files. The first one is our model right here that has the pause, but the second is going to be an additional model that does not have the pause.

To remove the pause, we’re going to select that area, then deselect and click okay. Now we’ve removed the pause. We are going to save the pause file first, but it’s important for you to know how to do both in insight. Since it’s a little bit of a tricky process.

The next thing that we’re going to do is locate the very first layer of the model itself. We want to create supports that only go up to this point and don’t go up into this hex cavity. The top of the hex cavity is just a flat layer. If we don’t tell it the layer to start at, it’s going to build support into it, which we could certainly delete out of there, but let’s avoid it from the start.

Now our very first layer, this circle right here is layer 48. Click the starting height button and click point 48. Now if we look from the side and then generate our supports, you’ll see it only generates directly under the part and not in that cavity, which is perfect.

The last thing that we need to do before we send this over to GrabCAD Print is to delete out that column. Select the circle, which is our column, and then just hit the delete button, which gets it out of there. With the tool path in the part up, you’ll see that we have our hollow surface on the interior. I’ll go ahead and shade that to make it easier to see. And then going down in the support structure, you can see that we do have a hole that our bolt will go into. And we’ve got plenty of space on the sidewalls for a metal hex bolt to fit as well as a little bit of clearance on the Z height.

At this point, we’ll go ahead and send this over to GrabCAD Print. We’ll get a slice preview from GrabCAD Print and a visualization for that Z pause. You can see it’s a blue layer on the right side of the slice preview. It’s also got a little call out, but you can turn that off if you want. You can see exactly which layer it is.

We added in a support base, so it added ten slices to it all. But you can also see over here on the left side, we can see visually that there is a little diamond for where that pause is in the part. And if we go down below it, we now have confirmed there is no support inside of the hex cavity, nor is there any support going straight down through that hole.

We are all set to go ahead and print this, or if we wanted to add multiple copies, which we are going to, we’ll go back and we’ll create one more copy of this file that does not have the pause and add however many we’re going to use to our build platform. In our case, we will use two more copies and then we’re going to send it to the printer! Embed metal in a 3D print, if you want to add utility to a prototype, fit and function test or even an end use part.

Check out the Carbon Fiber Nylon CF10 soft jaws sample part that goes along with the Ultimate Origin One sample part project!