Scion xB '06, in-dash Atom 330, Lilliput 889GL; details, pictures, links. Index: pg 1

**rdholtz** · 03-04-2008, 09:48 AM

Using Plastic Bottles
Unfortunately, the testing didn't go as well as I'd hoped. I only welded on test pieces, not on the duct components themselves. I found it's very difficult to weld thin pieces of plastic gracefully. The parts melt before they weld, leaving gaps, and welding the gaps makes more gaps. I suspect that welding thin materials is possible, but the results I achieved are far from pretty. It may be that I simply haven't discovered the proper technique, or it may be that I'm attempting the impossible.

Overall, the important issue is managing to get the extension and the duct parts connected in some functional manner that will provide structural integrity without any blockage to airflow. Because these systems have such thin walls, it may be that welding is not a good plan. It certainly isn't the only way. Perhaps one route is to simply use pop rivets to connect them at, say, six places around the periphery, and then seal the joints with something -- Liquid Electrical Tape comes to mind, although I don't know if it will stick to PE. One of the issues with PE is that very little sticks to it.

I'll keep attempting to weld thin sections to see if I'm just not using the right technique. The experimenting continues . . .

**lxt_123** · 03-04-2008, 10:17 PM

Try to insert something with more mass inside the thin tube, it needs to make good contact with the tube's wall and cool the inside of the tube, while you weld on the outside. A metal or PVC tube of the proper diameter will help. When you're finished, get the metal pipe out.

**lxt_123** · 03-04-2008, 10:20 PM

I just remembered a trick used in soldering jewelry and protecting pearls. use a potato, it is full of water that will cool the inside of the tube and can be easily shaped to fill your tube.

**rdholtz** · 03-04-2008, 10:47 PM

Excellent! Thanks for the suggestions. I'll try them. I think I have a potato in the fridge, too . . . now the shop will smell like french fries.

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I thought about this for a while, and realized that what I'm attempting is closely akin to welding sheet metal. The most common process used for that is spot welding, and it has an effect similar to pop riveting -- a series of small connections -- but requires no drilling or anything more than clean surfaces. So I'll try that, too.

**rdholtz** · 03-05-2008, 01:43 PM

Screen Location

The more I got into reconfiguring the bezel, the harder it became to decide which approach to take for the best result. All along, I'd hesitated to open the case of the Lilliput, wanting to keep it stock. But that just isn't going to work, and the screen is already off warranty, so what's the problem?

Today I split the case -- gently -- and measured the screen without mounting brackets. It's 7" x 8-7/8". That changes a lot of things. First, it eliminates the need to make the bezel wider at the top, as the 8-7/8" dimension exactly fits between the duct outlets. With the case, I had a problem; without the case, no problem.

The more I work out moving the climate controls, the more I realize I'm creating a new issue: where can I cram the head unit? With the controls moved down very far, I don't have enough space for the HU below them, because structural components of the dash intrude into the bottom of the space. So that takes me back to looking at how I can fit the screen in above the controls without moving them, and the smaller size of the case-less screen helps.

One thing I should make clear here: I want to mount the screen so it is NOT part of the bezel. The screen will be mounted in the dash, like the head unit is now, and the bezel will continue to be no more than a cosmetic cover that snaps in on top of it.

So, to help fit things better in reality instead of just in theory, I made a mockup of the screen from two pieces of thin plywood -- 7/32" -- screwed together, making them the same thickness, not including the circuit board. Here's the mockup:

Click image to enlarge.

I've already held it in place, and it makes the whole visualization routine much easier. I don't have to hold the entire monitor in place, so there's no danger of trashing an expensive part in a moment of oops, oh s***.

I still have more bezel redesign to do, now that the issues have changed yet again. But, with this uncasing of the screen, I finally feel as if I'm on the right path.

I need to figure out where the screen buttons will go; I may simply choose to hide them, as others have done. I also have to devise a mounting system. First, though, I'll make some mock brackets to hold the mock screen, and then I can get some decent pictures. Maybe I should print out a mock image of the XP boot screen to paste onto the mock screen . . .

**rdholtz** · 03-07-2008, 06:57 PM

More on Screen Location

To get the screen mockup to sit in its proper place, I built some temporary brackets from parts included in a Meccano kit I'd salvaged from a friend's discards. Meccano even comes with socket head screws and locking nuts, so it should be stable enough to bolt in and build around. Here's the back view (the bottom of the mockup is to the right):

Click images to enlarge.

The large stampings are the OEM mounts for the head unit. I made lines on the back of the board 7" apart -- the same width as the HU -- and just took an educated guess at where the brackets ought to go vertically, then fastened them in with some 3/8" hex-head screws I had on hand. Then I set the mounts in place and figured out which Meccano pieces would allow me to get a vertical position. I determined "vertical" by aligning the screen with the door trim, which is vertical; that's one advantage to having a car shaped like a box . . .

I put everything together just hand tight, and then moved things around until I got the screen in the position I wanted. Then I took it out and tightened one side up. I did a fit check, liked what I saw, and tightened up the second side to match. Because I'm using the OEM brackets, it drops right in. It's a little front-heavy, so the OEM brackets have to be screwed in to keep it all locked in position. I put the HU down where it will be installed so I can see how it all looks. I like it.

Here it is in place, from the driver's side, passenger side, and looking in the open right door:

Yeah, I did decide to paste on a boot-screen printout.

The white area surrounding the boot screen is the part that will be covered by the bezel.

Now that I know how the screen will be placed, it's time to build brackets for the actual screen. Once it's installed for a test fit, I'll make sure this mockup is positioned just the same. Then, at last, I can begin the actual bezel-building.

Note: the bezel side panels you see are pieces of the extra bezel I sliced apart. I've stripped the silver paint off with acetone.

**rdholtz** · 03-09-2008, 08:22 AM

Screen Mount

The brackets for the screen are going to be very different from the cobbled-together affairs I used to set the screen position. For the brackets I'll actually install permanently, I plan to use simple 22-gauge sheet steel. I'd use galvanized or stainless steel so no finishing would be necessary, but it wasn't available at either Lowe's or Home Depot, and I didn't want to scrounge around any further. I'll probably have to paint this after I finish.

Here's the driver's side bracket I want to replace:

Click images to enlarge.

Note that only the left two tabs are used in the Scion installation. This is a universal bracket used on a lot of Toyota head units, and the leg and tab pointing to the upper right don't attach to anything, so I'll eliminate them.

The mockup brackets were great for quickly getting the screen position set, but they won't work at all for the final installation. The Lilliput mounts on the edge of the screen, not the back, so I have to bring the bracket to the edge of the screen; that means the mounting feet will go in the other direction -- toward the center of the screen, not away from it. An advantage to this system is that it will make space to mount the circuit board behind the screen.

The first step was to sketch up what I thought would work and try it out in cardboard. It took a couple of tries to get it close. Here's the second version of that process, laying next to the system it's intended to replace.

It seemed to work just fine, so the next step was to refine the design and make a steel mockup of the result on some cheap, lightweight galvanized steel from Home Depot. I used a magic marker to paint the areas where marks would go, then used a steel scribe to make easily-read cutting lines in those areas. Once I had the basic shape cut out with sheet metal snips, I laid it up against the mockup, made sure the tab sizes, positions and angles matched, and used the vise to make the necessary bends so the tabs would work.

Making more fit checks with the existing mockup, I marked the hole locations with a spring-loaded centerpunch, matched drill bits to hole sizes, and got busy with the drill. Here's the resulting piece, plus a picture of it standing up in position next to the bracket it replaces. You can see that the new bracket is a whole lot less complex than the Toyota bracket and Meccano parts it replaces:

I stuck it into its location, and, yep, it fits great, but a little further refinement is necessary. The lower tab -- the one you you see on the left -- needs to be longer to accommodate the mounting fastener. If you look closely, there are two holes in the tab on the OEM bracket; the inner one is for the attachment screw, and the outer one is for a locating pin molded into the support. In mine, I only drilled for the locating pin because the tab is too short.

I think it would be a good idea to add a flange along the top edge for strength. All that's required for that is a little more material and a single bend. I also have to make a mount for the printed circuit board; it will be riveted to these side brackets.

Once those changes are devised, I can transfer the design to the heavier sheet steel and make the final brackets.

**rdholtz** · 03-09-2008, 10:09 PM

More on the Screen Mount

I added the material for the upper flange on the design and transfered the shape to 22-gauge steel. A fine-point pencil worked just fine for writing on it. Then I traced over the lines with a straightedge and a steel scribe. I used sheet metal snips to cut two blanks, including the one with the pattern. The blanks are 4-3/4"x8". I want these brackets to be exactly alike except for the final bend, and that's most easily accomplished by fabricating them together. I used a file to get two very clean, very straight edges that matched. Then I drilled two 1/8" holes through them, and riveted them together.

There's one curve in the pieces that isn't at a bend, so I drilled a 1/4"hole there; that makes a radius at that point, and eases the cutting. Here's the marked, riveted assembly with the extra hole drilled; the matched edges are to the back and right side.

Click images to enlarge.

Then it was time to head for the band saw. This could be done with a saber saw, but I have a small convertible bandsaw that works either vertically or horizontally, and that machine makes the job even easier. Staying just outside the cut lines, I made the cuts, then headed to the workbench to do all the finish filing by hand with a flat metal file. Here's the cleaned-up, still-assembled piece:

I added the 3/32" holes where the brackets attach to the screen, and then I drilled out the rivets and did a little cleanup finish-filing on the edges. I rounded the corners slightly, and made sure there were no rough edges to snag anything -- including me -- as I work with them. There are two small cables that come out of the lower corner of the screen, so I notched one bracket for that. Here are the pieces, ready for me to bend flanges and tabs. The notch is in the top corner.

One last job to do before bending: trace the final shape, so I'll have it in case anything goes wrong and I have to re-fabricate, or in case someone else is crazy enough to follow in these footsteps.

**lostreception** · 03-10-2008, 12:03 AM

very nice work. so are you going to relocate the ac or not now. and i thought it looked a little shallow in the bottom for the stock hu to fit there properly can you kind of post a llittle follow up on that. im getting more and more tempted to buy and aftermarket hu but i dotn wanna spend ~$50-$75 on a steeringwheel control unit that will most likey be useless with the CAR2PC adapter i bought for the XB. also how were u planning on extending the HU if you did. I was thinking of running the stock HU tucked backwards a bit in its current location setting all the EQs and SSP to 0 and center and simply running the carpc as the only audio input but i fear i will need the volume control or mute button at one point or another. I was also going to get the HD radio setup and just forget about using cds except thru the carputer. what do you think

**rdholtz** · 03-10-2008, 02:00 AM