View Full Version : Blast Door LCD Screen Mod Jr.

04-29-2007, 09:15 PM
Hi there everyone, Nerdy a.k.a. "Wannabeamodder Jr." here, and I'm finally ready to post the progress made on my build of the "Blast Door Project."

If you haven't seen my dad's post yet, you might want to look there (http://www.thebestcasescenario.com/forum/showthread.php?t=5499) to see how this whole thing got started :)

Near the beginning of my dad's thread, he mentioned that we would be building two of these things, one for his system, and one for my system. I waited until the final stages of the first build to start mine, so I could see how the idea worked out, since it wasn't exactly spot on with Crimson's original design (we had to make a few changes to adapt it to our build size and case).

When I started work on my build, I decided to take a different approach to building the linear actuator, not because the original design didn't work, but because I was in the mood to...eh..."tinker." I figured it wouldn't be any fun to build an exact copy of what's already been done.

Also, the first build was not without its problems. Even though the basic design was proven to work by none other than Crimson himself, our build had its share of bugs and problems. I suppose this is where years of experience in this sort of thing pays off, eh Crimson? :D

Among the few problems included instability of the actuator, sometimes too loose on the gear strip, sometimes too tight, the whole motor assembly wobbled too much within the main guide shaft.

Thankfully those problems have been fixed in the first build. I took note of them and set out to make a build that wouldn't have those same problems.

My original design was not too dissimilar from the original plan. It involved the same actuator/guide shaft/gear setup as before, but instead of the motor/gear assembly riding alongside of the main guide shaft, it would ride above it, with arms "hugging" around to the underside, and connecting to the guide piece that slides through the shaft. The gear strip would be on the top of the main shaft. Also the entire assembly would be made of styrene, because, for one, I don't like working with metal, and two, who needs all that metal just to raise and lower an extremely light blast door?

This was my "monorail" idea, which was basically thought of as a means of hanging the center of gravity of the motor assembly underneath the drive gear, thereby keeping it meshed with the gear strip and keeping the motor assembly more stable.

This idea had its advantages and also introduced a new slew of problems to overcome...

It solved the stability issue, but how would the weight of the entire motor assembly hang on just one gear? An obvious balance issue to overcome. Not only that, but size was still an issue as well. Crimson's design wasn't easy to shrink down to use in a standard case. At one point, the first build had a section of the main guide rail that extended out of the rear of the assembly box, and almost touching the power supply! Like the other problems, though, thankfully this one has since then been fixed. I didn't want to encounter the same problem in my build though, so changes had to be made.

So, a few days passed, a few thoughts rattled in my brain, when all of the sudden, an idea smacked me in the face out of nowhere. I was digging in a box of old junk, and I found a model train. HO scale to be exact. I tore open the train, dissected it, and found this:


I didn't get a photo of the train intact, I was too busy brainstorming. Luckily, however, I found a picture online of an intact train with more or less the same setup as the one I dissected.

Pretty much, this one compact wheel unit was the beginning of an entire actuator motor setup. I only had to find a way to drive the wheels.

I began working, and ended up with this:



Essentially, the actuator is...a tug train/roller-coaster hybrid. I have two straight pieces of track, one on top of the other like so:


The tug rides on the top portion of the track, while a guide set of train wheels, attached to the tug, ride on the underside portion of the track, keeping the tug in contact with the track and to keep it from derailing.

Pretty much my "monorail" idea, re-imagined.

Before this photoshoot, I had the guide wheels already attached to the tug, but the attachment method was rather clunky, so I detached them and am currently coming up with a better way to attach them to the tug unit.

Before that, I ran some initial tests to check the power of the motor and to see if it would have enough grunt to raise/lower the door. I gripped the actuator in one hand, the battery in the other. Touched the wires to the battery, and poof. It spat the track out with such force that it nearly hit me in the face from full arms' length!

As for the main case or "box" that the unit goes in, the design is essentially the same as the first build. There were a couple of problems with misaligned parts and warping due to misalignment, angles not being square, etc.. Pretty much the first build was done by the age old method of "eyeballing." Sure a few measurements were used here and there, but most of it was trial and error. I set out to perfect the first design, by measuring and drawing each part exactly to scale in a design program.

Interestingly enough, I didn't use AutoCAD or Sketchup, or any other program used solely for designing and blueprints.

I used Photoshop :D

I set up the page size to match a standard 8.5 x 11 sheet, and set up my grid and rulers to do 1cm x 1cm boxes, and away I went.

After a few days, I nearly finished the front view.


A few more days and the side view was nearly done.


Of course I have it set up to where you can view/hide different parts/elements of the design, I just have everything unhidden in the pictures.

As you can see, I have designed this actuator to make use of the full length of the track, with no wasted space at all. This let me fit the whole build snugly into a 17.3cm long space.

I still have to design the method of attaching the tug to the door, the mount for the entire actuator assembly, and to redesign the method of connecting the guide wheels to the tug unit.

As for progress on the box construction:

One aluminum CD-ROM shell from random mutilated CD-ROM drive. This will be used as the base for the box to be mounted inside the PC case.


Closeup shot of one of the sidewalls. Notice the shorter blast door rail as compared to the first build. A part of my "smaller is better" motive in this build.


An overhead shot of the sidewall:


After much gained experience on the first build, I opted to build the blast door rails right onto the walls, instead of building the rails separately, and then gluing them onto the walls, as with the first build. This helped out a lot, there is no bowing or bending to be seen from the sidewalls this time around.

Here is an overhead shot of the layout of parts that I have fabricated already:


Progress is going very well so far. Expect an update in a few days. If not Tuesday, then Thursday at the latest. My college schedule this quarter is quite cramped on Mondays, Wednesdays, and Fridays, so I don't get to work on it as much as I would like during the week :(

Well there you have it. I hope you enjoy my build as much as you enjoy my dad's. 8)

05-02-2007, 08:26 PM
Ah, the good ol' Hummer. I had a blast modeling that thing back in the day, when I knew jack squat about 3d modeling. Good times!

I used a program called Zmodeler to model it. A great program for beginners! It doesn't have that massive maze of buttons, options, and windows upon windows of settings that some of the professional programs like 3dStudioMax and Maya have. It's not as powerful as the big guns, but like I said, it's great for beginners.

Now, back to the build. Update time!

I've made a good deal of progress on getting the upper half (tug) and the lower half (guide wheels) connected together in a manner that is much more stable and sturdy than the previous method. Of course, now that I think about it, I pretty much rushed the previous method and threw it together, because, at the time, the whole actuator idea was still in its proof of concept stage. That stage ended quickly when the thing spat the track out at me as I mentioned in my first post :D

For those that are curious, here is how I had it set up before:


Pretty much a bolt on either side, fixed to the top half, screwed into nuts attached to the bottom half (no pun intended), and tightened to make both halves "hug" the track. It worked, but it was ugly, and it wasn't really a sturdy way of keeping the two halves attached. Both halves tended to go askew from one another ever so slightly.

Here's what I have now. It isn't finished yet. I don't have the tightening mechanism in place, but that will be the next thing I work on.





As you can see, this new version consists of a larger hollow tube placed on the four corners of the tug unit. Four more smaller tubes are placed in the same relative spots on the guide wheels unit. The smaller tubes slide into the larger tubes, giving the whole unit four points of support.

The tightening mechanism will consist of two more large hollow tubes attached to the guide wheels unit. These will be tapped/threaded and a screw will come down through a hole in the top of the tug unit. The screws go into the threaded tube, and will let me tighten/loosen/fine-tune how hard the whole unit "hugs" the track.

More on box progress...

I've ditched the floor, front, and rear walls that were shown in my first post. They just weren't square enough and straight enough to make a box that was as perfectly shaped as I could get it. I must have been having a bad day when I cut those, because they were poo.

So I remade them :D

They are of much better quality this time around.

I did a mock construction of the box to show you :D
Everything came together perfectly with no gaps, and no signs of crooked edges and unsquare corners.




The last pic shows how much space I have to work with inside this thing. Good thing I drew this up in Photoshop first and designed the actuator to use every inch of track that was there :banana:

05-06-2007, 11:31 AM
Front page huh? Wow, I'm honored! :D Thanks for the comments everyone!

Update time!

I've made tons of progress since the last update.

The tug/wheel unit is, for the most part, done.




As you can see, I've added two more pipes in the middle for the screws to screw into and tighten things up. Also you can see that I've added bumpers to the front and back of the guide unit to keep it from crashing at the ends of the track.

Now, on to the box unit, starting with the rear wall.

I've added holes in the rear wall for the two molex and composite cable connectors to mount into. I'll let you guess what the hole in the center is for :banana:


Rear wall with connectors in place.


Now for the front wall.
I added a hole in the front wall to route cables to the screen. Again, I'll let you guess what the indention in the middle is for ;)


And now for the side walls.

No doubt you've seen the screw holes on the edges of the front and rear walls. I opted for a less permanent means than glue for holding the box together. As Crimson has pointed out before, I didn't want to build myself into a corner. Here are the side walls with newly added L-brackets.



An overhead shot of the newly modded box pieces.


Now we're ready for assembly!

...a few minutes later, and we have an assembled, structurally sound box.


Now it's time to mount that track.

After spending hours trying to figure out how to mount the track into the box when there was virtually no space at all on either end to work with, I came up with an ingenious idea. Remember the hole in the center of the back wall, and the indention in the middle of the front wall? I'll let pictures speak for themselves.









Not only does this method of mounting the track save TONS of space, but it's relatively simple and is easy to disassemble/remove from the box.

With the track in, we can now mount the actuator.




Now it's time to fire up this sucker for test #1 :twisted:


In the video, I was running the actuator at around half power with the variable speed POT kit that dad ordered. That's all it needed. With full power, it zips back and forth incredibly fast. I have no doubt in my mind that this will have enough grunt to raise and lower the blast door.

My design showed that I needed 11cm of clearance from the back of the actuator to the back wall to get the door to raise high enough. I made my design to use every inch of track that was there, so I would have exactly 11cm of clearance for the actuator to move, while still being able to fit the entire thing inside the box.

The actual build has remained faithful to the design. There is EXACTLY 11cm of clearance for the actuator to move.

Stay tuned, next week I'll begin working on the door itself!

05-15-2007, 05:31 PM
Uh...BUMP. :D

Sorry for the lack of updates, I took sort of a mini-break from the project, but I'm back on it.

So I've finished the blast door, I have mounted it to the actuator, and the actuator does indeed work (though I had to utilize a few crafty ideas to minimize slippage of the wheels).

Crafty ideas such as gluing a strip of rubber band onto the top of the track :D


The mount I used to attach the actuator to the door is actually quite simple...



Unfortunately, I can't show you a video or even pictures of the assembled build in action just yet. It's already in pieces and is being painted. :redface:

I can, however, show you progress of the painting. :banana:




As you can see, I'm taking a different approach to painting my door. I opted for an industrial sort of "warning stripes" look. As you can see, the black stripes are done. I will paint the yellow stripes tomorrow. Stay tuned!

05-16-2007, 08:54 PM
UPDATE TIME!!! :santa:

The door is painted, the box is painted (at least the parts that will be seen from outside the case), and the actuator is ready to go. So I put this puppy together for yet another demonstration. :banana:

I will let the pictures do the talking from here:







The door seems a little sluggish when raising only because I'm using a 9-volt battery. This is not the case with the 12v molex power running to it.

So then I did a test fit into the case.

She fits perfectly!




Another video of it inside the case:


We've shifted away from using the variable speed POT boards that we bought. We discovered our builds like a sudden jolt of electricity to get the actuator to start moving from a standstill, and that, by the time you raise the POT up to full power, the actuator has already reached the end of its travel. So, I guess we'll have to find another use for the POTs in some other project.

Instead, we're going to be using a double-pole double-throw momentary rocker switch to change the directions. There will be a limiter switch at the rear of the box to make sure the actuator stops completely when it's ended its travel. There won't be one up front because whoever is operating the door should be able to see when to release the switch.

Closeup of the rocker switch we're using:


Thanks to dad for wiring this sucker up for me! :D

No hints on where we're mounting this switch yet, but until we show its final mounting place, consider this project very much still in progress ;)

05-17-2007, 11:18 AM
What's in store for the rest of the case? Well...I can't tell you quite yet.... It's a secret ;)

I can, however, show you the first steps to what we're doing next. As with the blast door, I will be drawing and designing what we do next in Photoshop. And what better way to start than to draw the case to exact measurement :D

With the blast door, I just jotted down a few measurements with descriptions beside them and used that to put together the design in Photoshop.

This time around, there were too many measurements to keep track of in a notepad, so I drew a mockup of the case:


That one semester of drafting class in high school finally paid off :banana:

After many hard hours of work, I completed drawing of the side view of the case in Photoshop, exactly to scale and incredibly accurate:

Of course the image I'm posting here is scaled down to fit, but the full sized image is 2410 x 2410 pixels in size, or 33.5in x 33.5in lol.

For comparison, here is the real thing (a pic from some review site):


For kicks, here's the Photoshop blast door box drawing inside the Photoshop case drawing:


Gonna have to find someone with a plotter to print this sucker out...

05-17-2007, 04:58 PM
My dad told me he has a friend at work that might be willing to do it :)

I have the front drawn now :D


07-04-2007, 06:26 PM
Well, finally time to post some pics of the new rigs, as well as completed and installed blast door mods!

We'll start off with the beefy insides:





The rear of the system and showing the header where the switch box/video out plug into...


The switchbox itself...


And finally,
Here it is, NEMESIS, up and running!


The completed blast door...


In the words of a random Storm Trooper from Episode 4,

"Open the blast door! Open the blast door!"


Door opened and screen working...

The camera doesn't really show the screen very well, but you get the idea. With this being one of the first real casemods (err...additions) that we've done, I am very proud of the end result!

07-05-2007, 02:01 PM
As for power, it is running on 12v from the psu. As for video, it is connected to the video out on the back of the 8800 Ultra via a composite to s-video adapter.

Link to original thread. (http://www.thebestcasescenario.com/forum/showthread.php?t=7860)


For those of you who would like to see a vid of it in action, here it is!

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