Tutorial

Figure 1. The model to be built.

If you have just started VirtualMEC, you should have a blank document window open. If this is not the case, please close any open document windows and then open a new one selecting File New .

Verify that Flat Colour Rendering button is pressed.

Let's start with the first part we want to add to the model. You can choose any part you like to start with; in this case we will start with the central Trunnion No. 126. The Parts Bar should be visible on the right. If not you can click to show it. Now you can locate the Trunnion. Please take a moment to explore the different views of the Parts Bar; you may want to choose the type of view you are more comfortable with. You can also dock or undock the Parts Bar, as you prefer, by dragging the top handle. Once you have selected the Trunnion, click .

Verify that the Drag toolbar button  is pressed. Just click and drag your mouse around the model to see it from different points of view following your mouse movements. You can zoom in  and out  and you can pan the model using the scrollbars or clicking and dragging using your mouse central button or mouse wheel. Once you have mastered the various movements, end with the Trunnion in about the same position as in Figure 1.

Now it's time to add a Bolt to the Trunnion. Locate the correct hole nearest to you, where you want to fix the Double Angle Strip No. 48a. Simply click in that hole. A Bolt No. 37b will appear in the chosen hole. The Bolt is selected (red colour) so that you can operate on it. The first thing to do is change its direction. While it is still selected, click on the Invert button .

Now you can add the Double Angle Strip No. 48a. Locate it in the Parts Bar and double-click it. The Double Angle Strip adds itself to the selected Bolt, through the correct hole, but it is incorrectly rotated. Click on it to select it, then press the Rotate 180° button . Now it should be in the correct position. Re-select the Bolt and add a Nut to it by pressing the Add Nut button .

Repeat the same procedure to add the other Double Angle Strip.

With the Axle Rod still selected (if it is not selected, click on it), add the following parts: a Flat Trunnion No. 126a, a Spring Clip No. 35, a Pulley No. 22 which forms the wheel, another Spring Clip and another Flat Trunnion. It doesn't matter for the moment if the Trunnions are not correctly oriented, you can adjust their positions later. You should have reached a result similar to the one in Figure 2.

• [Scooter Phase 1]

Figure 2. The rear axle.

Verify that the Axle Rod movement arrows are still displayed (otherwise double-click on the Axle Rod) and make use of the red arrow to correctly position the Axle Rod. It should extend by the same amount from each Double Angle Strip. Yet even though the Axle Rod now passes through the hole of the second Double Angle Strip, VirtualMEC is still not aware that the hole and Axle Rod belong together. To let it know that, you must "hook" the Axle Rod; once it is selected, click the menu Part Hook.

We can now proceed to correctly position all the recently added parts. Start with the last Trunnion. First of all, make sure all parts are deselected by clicking outside the model. Then double-click on the Trunnion and drag its big red arrow until it reaches the corresponding Double Angle Strip. Since every part is hooked, no parts should go beyond their allowed range. While the Trunnion is selected, you can rotate it to the correct position using the Rotate 90° button .

In the same way, position the Spring Clip against the Trunnion and the Pulley wheel in the middle of the Axle Rod. Finally, rotate the first Trunnion to the correct position.

Adding the Motor Tyre to the wheel is extremely easy: select the Pulley wheel, then locate the Motor Tyre No. 142c in the Parts Bar. Double-click it.

Your model is beginning to grow. Now’s the time to save it. Click the Save button, choose the desired folder and give it a name. You should periodically save your models to avoid losing your work if an error occurs.

• [Scooter Phase 2]

It's now time to add the rear Plastic Plate. First of all click in the last hole of the left Double Angle Strip to create a Bolt. Correctly orient the Bolt by inverting it (click the Invert button ). Add the Plastic Plate No. 194. You will notice that the Plastic Plate has been added to the Bolt, but not through the correct hole. With the Bolt still selected, click in the desired hole in the Plastic Plate; the Plastic Plate will jump to the new position. Select and rotate the Plastic Plate to make it vertical. Your model should now look similar to the one in Figure 3.

Figure 3. The rear Plate about to be bent.

We can now proceed to bend the Plastic Plate. With the Plastic Plate selected, click the menu Part Add Bend. Locate the bend arrow and drag it until the Plate has a right angle bend. You may want to find a point of view that is more suitable for that operation. Remember that you can always drag the image to find a better view. If you have trouble with your first bending, don't worry. You can always undo your last actions, by clicking the Undo button , and try again until your model looks like Figure 4.

If, during the process of bending, you inadvertently click outside the part, the bend selectors disappear. To have them reappear, click the part to be bent, then click the menu Part Edit Bending, then select the bend (the red sphere) and you are back again.

• [Scooter Phase 3]

Figure 4. The rear Plate initially bent.

To begin with the bend is quite sharp; we need to soften the curve. With the Plate selected, click the menu Part Soften Bend twice. Little spheres will appear about the bending axis. Drag one of them until you reach the following figure. If you can’t see the spheres, try zooming the image.

Figure 5. The rear Plate correctly bent.

The Plate is now correctly bent. You can deselect it by clicking anywhere outside the model.

If, after building more of the model, you want to go back and adjust the bend, you may find that the Bend menu is greyed out. This happens if the Plate is fixed by more than one Bolt, and bending would be impossible in real life. You need to remove (or unhook) all-but-one of the Bolts (or Axles), and the Bend menu should reappear.

It's now time to make some fine adjustments to the model. As you can see, the bent Plate and the Trunnions intersect at some points and that looks ugly. VirtualMEC is not able to make the necessary adjustments by itself, instead it gives you all the tools you need to make them yourself.

The Trunnions also need to be moved away from the Plate slightly. You can obtain a satisfactory result by rocking them along the Axle Rod. Double-click a Trunnion, then alternately click and drag the two little curved arrows until you reach the desired position. Feel free to experiment until you are comfortable with every movement. Always keep in mind that the Undo button is available to you.

When you need very fine adjustment, you can use a nice VirtualMEC feature called Remote Control. Let's suppose you need to orientate a Trunnion vertically. Simply click the correct arrow (without dragging it); VirtualMEC automatically remembers the last arrow clicked or dragged. Then rotate the model so you get a good point of view. Now, if you press Ctrl while you drag the mouse, VirtualMEC acts as if you were dragging the arrow itself, even if you are not actually dragging it. It's like having an invisible arrow just under your mouse.

Once you have practiced Remote Control for a while, you will realize that finding the correct position for any part that needs fine adjustment is easy and fast.

Now it's time to add the tail lights and obtain the result shown in Figure 6. Proceed as follows.

For the left light, select the Bolt on the left side of the body and click the Add Washer button . Invert the Bolt and add a Nut to it. Now click in the corresponding holes in the right side; invert the Bolt, add a Washer, re-invert the Bolt and add a Nut.

• [Scooter Phase 4]

Figure 6. The rear part of the model.

We can now proceed with the saddle. We need a couple of Angle Brackets No. 12 to fix the upper part of the Plate to the Trunnions. Click in one of the elongated holes on the edge of the Plate and then add an Angle Bracket. You will want to bolt the elongated hole of the Angle Bracket to the Plate, so click in that hole while the Bolt is selected and the Angle Bracket will jump into place.

Now you can do a couple of things. Double-click the Angle Bracket and make use of the correct arrow to slide it against the Trunnion. Again, to do so, find a comfortable point of view and use Remote Control if you need it. The holes in the Angle Bracket and the Trunnion are probably not in perfect alignment. You may need to slide the Angle Bracket a little bit forward. To do so, double-click the Bolt (arrows appear), then click the Plate (new arrows appear). Dragging these arrows will move the Bolt and everything attached to it, but NOT the Plate you clicked. Try it until you are comfortable with this “double plus single” click feature. (Remember to use the Undo button, if something goes wrong.)

Complete with Nuts and Bolts and do the same for the other side. Your model should now look like the one shown in Figure 7.

Figure 7. The rear part of the model almost complete.

The saddle is a Trunnion No. 126 attached to a Fishplate No. 10, which is attached in turn to the central elongated hole of the Plastic Plate. You should be able to complete it by yourself. See Figure 8 for reference.

• [Scooter Phase 5]

Figure 8. The rear part of the model complete with the saddle.

You are now ready to proceed with the front part of the model. Figure 9 shows the front assembly with the Trunnion and a Perforated Strip No. 5 made transparent in order to see the inner details.

Figure 9. The front part of the model.

A Fishplate No. 10 is lock-nutted to the front hole of the Trunnion. Click in the Trunnion's front hole, add a Nut, add a Fishplate and finally add another Nut. The Fishplate needs to be rotated by 90°. You should be able to do all this by yourself.

The other end of the Fishplate must now be bolted inside a Double Bracket No. 11, with uprights pointing upward. Click in the front hole of the Fishplate to create a Bolt, then, with the bolt still selected, add a Double Bracket. With the Bolt still selected, choose the correct hole of the Double Bracket (the central one). The Double Bracket will jump into place, but is still not correctly oriented. Select, invert and rotate the Double Bracket as necessary until it’s facing the way you want. Invert the Bolt and add a Nut to it. Your model should now look like Figure 10.

Figure 10. The model so far.

It's now time to add the two Perforated Strips No. 5 to the Double Bracket. Since we do not want the steering column to be exactly vertical, we will need to rake the Perforated Strips backward. We could do so by rotating each of them individually until they are perfectly aligned, but in this case we'll use a different approach that makes it easier to achieve perfect alignment. Proceed as follows.

Add the two Strips in the vertical position. To do so, click in the hole in one of the uprights of the Double Bracket, invert the Bolt if needed, add the Perforated Strip, click in its second hole to reposition the Strip, invert the Bolt again and add a Nut. Do the same for the other Strip on the other upright. Your model should now resemble Figure 11, with both Strips pointing vertically into the air.

• [Scooter Phase 6]

Figure 11. The steering column in vertical position.

Now let's add the handle-bar through both Perforated Strips. To do so, first select Axle Rod No. 16 in the Parts Bar, then click in the top hole of both Perforated Strips. Position the model until you can see the second hole through the first one. Click in the hole and the axle appears. If you have done everything correctly, you should be able to verify that this new handle-bar is “hooked” to both the Strips. Please do so: double-click the Axle Rod and move the red arrow. You shouldn't be able to unthread the handle-bar from the Strips.

It's almost time to rake the steering column. But first, let's say a few words about how VirtualMEC handles movements of parts. If you double-click a part, VirtualMEC displays a set of arrows that originate from one of the holes containing a Bolt or Axle Rod. For example, if you double-click one of the Perforated Strips No. 5 that you have just added, VirtualMEC will display a set of arrows around the hole containing the handle-bar. Try it. Now, if you click the Bolt, the set of arrows will move there. Please note that you have NOT selected the Bolt, you have simply changed the reference hole for turning operations. The Strip is still selected. Now, what happens if you, say, drag the green arrow?

The Perforated Strip will rotate (in fact it's the selected part) with respect to the reference hole (the red hole with the turning arrows). Other parts that the Bolt passes through will not turn, and neither does the Bolt itself. But the handle-bar, because it is “hooked” to the Strip, will follow the movement of the Strip, as will all other parts attached to the handle-bar: in particular the second Strip and its Bolt, and, through them, every other part of the model, since they are all connected. But we did not want the whole model to rotate around the reference Bolt. But you should try it, just to see what happens. Then remember to press the Undo button to go back to the previous situation.

So what do we have to do if we want to rotate the steering column, and nothing else? The problem arises because the Bolt on the second Strip is “hooked”. If we remove this Bolt, the problem no longer exists. Or, even better, we can “unhook” it. Unhooking stops the Bolt from propagating the movement of the second Strip to the other parts of the model.

[NOTE] Beginning with release 1.2.4, VirtualMEC has the ability to automatically detect Bolts and Axle Rods that are coaxial with the Bolt that is acting as a pivot. So unhooking coaxial Bolts or Axle Rods is not needed anymore (VirtualMEC will do it for you). So, in this particular case, unhooking is not necessary. Anyway it is still recommended that you practice with unhooking, since in other situations that might be needed.

Once you have understood the logic just explained, the task is very simple. Select the Bolt you want to unhook and click the Part Unhook menu. Now double-click the first Strip, click the Bolt around which you want to rotate the steering column, and drag the green arrow. Only the steering column rotates (consisting of the two Strips), and you can now incline it in the desired position. Finally, don't forget to rehook the Bolt to the second Strip: select the Bolt and click the Part Hook menu.

Let's proceed with the fork. The fork also needs to be inclined and we can repeat the above procedure, but later. First, let's add the two Curved Strips to the handle-bar. Select the handle-bar and add a Curved Strip Stepped No. 90a. It will appear next to one of the Strips on the outer side. Since Axle Rods, unlike Bolts, do not have heads and stems, it's not easy to anticipate where a new part will be added. You will get a hint if you double-click the Axle Rod. The red arrow shows where the next part will be added. If you now invert the part , the red arrow will move to the opposite end, and when you add the second Curved Strip, it will appear on the other side. Put simply, if a part attaches itself to the wrong end of a Rod, you simply Invert  the Rod and try again.

Once you have added the two Curved Strips, deselect the handle-bar by clicking outside the model and, with the aid of the Invert and Rotate 90° buttons, position the fork as shown in Figure 12. Then you can add a Spring Clip No. 35 at each side of the handle-bar to keep things in place.

Figure 12. The fork in raised position.

We should now rotate the fork to the correct, downward position. We have several choices: we can rotate each part individually until things line up correctly. Or we can add the wheel, in order to "lock" the fork so that it moves as a unit. Or, we can use a little trick: we insert a dummy Axle Rod through corresponding holes on either side of the fork. This also “locks” the fork. Then we position the unit in the desired downward position, and can simply remove the Axle Rod afterwards. This method is the easiest to implement.

Rotate the model so that the last holes of the fork arms are aligned and you can see through both. Select an Axle Rod in the Parts Bar (any Rod will do, they are all long enough to go through both holes). Click on the holes and the Rod is added. Now the fork assembly will move as a whole. Double-click one of the arms, verify that the rotation arrows are displayed around the handle-bar, and drag the green arrow to rotate the fork into the correct position. The correct position is reached when the second hole from the top of each fork's arm coincides with the second hole of the corresponding Strip No. 5. Now we can select the dummy Axle Rod and delete it.

• [Scooter Phase 7]

Moving on, let's do the front wheel. At the end of each fork arm you need to add a Fishplate No. 10, using its elongated hole, and a Washer. See Figure 1 and Figure 9 for details. Once again, we want to line up the Fishplates so that the Rod can be threaded through both.

To mount the wheel, proceed in a similar way as before. Select the Axle Rod part No. 18b in the Parts Bar, then click on the hole of the nearest Fishplate. The Rod is added through both Fishplates. (If you click on the hole of the farthest Fishplate, the Rod is added through the farthest Fishplate only.) With the Rod still selected, double click on Pulley No. 22. It is added between the Fishplates. (If not, you can correct the Rod and Pulley position using Ctrl+Drag. Any time a Rod or Pulley needs to be moved beyond its natural stop, simply press Ctrl while dragging the red arrow.) Now centre the Axle Rod through the forks, and centre the wheel on the Axle Rod. Finally, add the Motor Tyre to the Pulley.

• [Scooter Phase 8]

Figure 13. The model is almost complete.

To add the front Plastic Plate, click in the forward hole of one of the Angle Brackets and add a Plastic Plate No. 194 to the new Bolt. Choose the correct hole in the Plate and then orient the Plate correctly. Verify that the hole of the other Angle Bracket almost lines up with the required hole in the Plate (this is why we added the Washers). You may want to slide the Plate slightly so that the holes line up better.

Now, at last, you can add the second Bolt to the Plate with its Nut. Finally add the third Bolt and a Washer to hold the windscreen; the windscreen is a Transparent Plastic Plate No. 193. The model is now complete and should look like the one shown in Figure 1. Remember to Save your work!

• [Scooter Phase 9]

Finishing touches.

Once you have created a Unit, you can recall it at any time to move it. Locate the Current Unit combo box (it should be empty if nothing is selected), and click the pulldown button. You can now select Steering Assembly, or whatever name you just gave the Unit, and a green arrow should appear. Drag the green arrow to operate the steering. Click outside the model when you are done.

• [Scooter Complete]

Let's briefly explore some other VirtualMEC features.

Have fun with VirtualMEC!