Hi, I've made some Vacuum engines in LDD and I want to show them and explain all the problems with some of the tools that I've encountered when building them. Any comment and suggestion is welcome.

First I want to talk about the "Hinge align tool" and how it does not work when connecting the piston rods and valves rods to the crankshaft. I have found no easy way connecting the parts together and you must to do it by hand and it was like throwing darts at a dartboard the piston rods and valves rods being the darts and the crankshafts the bulls eye. Now putting the valves and pistons in the engine design requires building a guide on the digital model to get them centered. The guide process must be removed from the model when the piston and valve are connected up.

The building instructions that were produced came out weird and impossible to build like that. So I had to take the individual parts that make up the engine and make separate plans for the frame, cylinder, pistons, air block, and valves and make the plans for them and then through screenshots I try to show you how to put it all together. There should be a way to group certain parts together and label the group so that you tell the computer how this group is made and where it will connect with on others groups.

I want to finally add that I was able to crudely rotate the crankshaft along with moving the pistons and valves up and down with the hinge align tool, but that idea only didn't last because the computer gave up looking for the spot. There was no real direct control on the crankshaft. Any other Idea on turning the crankshaft(axle) around to move the pistons and valves didn't work. There should be a way to show the function of the construction buy turning the axle around.

I would make and some more engine designs in LDD but connecting the piston and valves is the most difficult thing to do and is really becomes guess wor on every crank throw. It was my first time building with LDD The flat-4 engine was my first design I made in LDD.

Edit: I've put a .lxf of the flat-4 engine on brickshelf

Edited April 21, 201311 yr by Boxerlego

@ Boxerlego: I know that using the LDD "Hinge Align Tool" for piston crankshafts is time-consuming! Do you plan on building this with real Lego parts?

@ Boxerlego: I know that using the LDD "Hinge Align Tool" for piston crankshafts is time-consuming! Do you plan on building this with real Lego parts?

Thanks! That was a good question. I want to add that you dont want to use the "hinge align tool" for connecting the piston the the crankshaft. What you will need to do is set the piston rod at the angle that connects to with the crank. The crank does not move to connect with the piston. The piston has to move to connect with the crankshaft. The "hinge align tool" really does no good at connecting the piston and crank together I must say.

I've already made the engines. They were made awhile ago. I've got couple of new engine in the works right now and testing ideas. Currently I've built two kinds of V4 engine, One with a 90 degree V angle and the other is at a 60 degree V angle. I am planing on making a video and comparing the two V engines. I will make a LDD design of the V4 at the 60 degree V angle. I've lost my original LDD file of my V4 engine so another one will haft to be made if a .lxf file is wanted.

All these engine are built using the same cylinders. It is the core of the engine foundations. The attention to detail is very high in building the engines there are many things you want to avoid like loose brick connections. Here is a topic on the matter..http://www.eurobrick...showtopic=45547

Edited April 21, 201311 yr by Boxerlego

Interesting MOC.

Can use scientific calculator to find perfect angles of piston for any degree.

This is a 45 degree sample.

Interesting MOC.

Can use scientific calculator to find perfect angles of piston for any degree.

This is a 45 degree sample.

Thanks, That is very Interesting solution. But you shouldn't haft to run to a scientific calculator to build this stuff in LDD. Putting the yellow pistons in the engine cylinder is a good example on how difficult it is because those yellow pistons don't line up or go in the engine cylinders. You haft to bend the piston head on the rod to match the angle of the engine and the angle the rod to the crankshaft...then you got to disconnect the rod from the piston so the can connect on the crank and be in the cylinder where you will put the piston head in to connect with the rod... it is a back and forth process that is unnecessary to get the piston in the engine cylinder and connected to the crank shaft.

The Idea is you should be able to have the piston head and rod in the engine cylinder together and you angle them together as a group to connect to the engine frame and attach the piston rod to the crankshaft and your done.

LDD is missing a "slide" feature, like the one is present in SR3D Builder if I'm mot wrong.

That, aside as the "working gears" feature would allow not only to build without bother of the precise positioning of pieces, but also allows to pose the model to show the functions (like the steering) without the need of disassemble parts of the model to put the parts at the right angle.

I was building the UCS Millennium Falcon and at some time I gave up because using the hinge align tool it literally bent (like when you use 1X2 bricks to build a curved wall) some sections and I was not able to attach them anymore without disassemble the entire section, not to mention that LDD crashed almost 2 times every 5 uses of the hinge align tool because the large number of pieces.

As for now I think I'll follow the bbqqq suggestion and use scaffholding to put pieces in the right position (like I did with UCS R2D2) ;)