Introduction: DIY Automotive Dashboard Gauge Pod
I needed a set of gauges for my truck, but none of the gauge pods available held more than three gauges - or four if I didn't want to be able to use the sun visor. So this is what I came up with - with a little inspiration from the internet, around $50 (I had some of the stuff already, I don't know what it will cost you), and maybe 10 hours of actual labor. However, with the cure time for epoxy, I think you'd have trouble getting it done in a weekend. I had about a week in building the pod.
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Step 1: Tools and Materials
Here's what I used:
2" diameter plastic pipe for 2-1/16" gauges. Black ABS plastic seems to be preferred, but I imagine PVC or most other kinds would work - just make sure the epoxy you use will bond to what you pick.
Epoxy - about 5 oz.
Fiberglass and body filler (in hindsight, ditch these and use only epoxy)
Paint - I used SEM Plastic paint.
Permanent marker, crayon, pencil... whatever will mark best on your install location.
multi-function oscillating power tool
half-round coarse file
This is just what I used to make the gauge pod itself, it doesn't include everything I used in the installation.
Step 2: Safety
Try to end the job with the same number of fingers, toes, and eyeballs as you started with. Hot things can burn you, sharp things can cut you. I'm not responsible for damage you cause to yourself, others, or anything else. I'm telling you how I did it, not the right way or the safe way to do it. If you don't understand the wiring portion, admitting you can't do electrical work to a technician will be far less embarrassing than admitting it to the firefighters or your insurance company.
Step 3: Cut and Epoxy the Pipes, Then Figure Out Exactly Where You Want the Gauges
I didn't get photos of this part, but it's fairly straightforward. Scuff up the exterior of the pipe with coarse sandpaper. It's easier to scuff it up when it's still one piece. Cut pipe sections to a bit longer than you think you'll need. I started with about five inches, but once I removed the trim piece I found that two adjacent clips on my trim piece would need to be cut off to extend the pipes further back so I cut the pipes shorter.
Now lay the pipe sections on a flat surface with the edges touching and sit something heavy on the outsides to hold the sections together. I couldn't find even one perfectly round plastic pipe at the hardware store, they were all ovaled just a bit, so I oriented them with the tall side being vertical. If I had this to do over again, I would have made the larger dimension horizontal, it would have given more space between the gauges and less plastic protruding from the top. It wouldn't make much of a difference, but I'm aware that it could be about .05" better than it is... and by Step 8, I was getting worried I'd have to trim the bezels on the gauges
Now mix up some epoxy according to the manufacturer's instructions and apply it where the pipes touch. Pull the pipes apart enough to let some epoxy run between them and then push them back together, rolling the next one into place each time to get a bit of epoxy all over the joint. Once the epoxy was set up, I ran it through my table saw to get the edges perfectly square.
It will be easier and more forgiving if you pick a part that comes off easy. If you cut into the dashboard, you could easily have 10+ hours fixing any mistake, depending on the model of your vehicle. I was lucky that Ford has a fairly easy to remove instrument cluster trim panel on their trucks, AND it's exactly where I would have picked to put the gauges.
Step 4: Mark and Cut Out the Opening
I held the pipes in place and marked about where I should cut. I left 1/16" to 1/8" past the line and then got it 'perfect' with a rotary tool. You don't have to be too precise, just get it where it sits how you want it to. As you can probably see, the pipes shifted a few times while I was making my marks. Some spots were low, some needed a bit more taken off. You'll never see this part, and the epoxy is probably as strong as - or stronger than - the plastic. I wouldn't spend time getting the pipes to sit in perfectly. The more pipes you have, the more trimming and checking you'll have. Just get them at the angle you want. Shim them up if necessary.
Step 5: Epoxy the Pipes in Place
I recommend leaving the piece installed in the vehicle for this step unless it's a very rigid part, you want the epoxy to cure in the position it will be in the vehicle. If it's not, there will be an increased chance of the epoxy separating from the plastic - even the most flexible epoxies are much more brittle than automotive trim plastics. If the plastic flexes more than the epoxy can, the epoxy will just peel off. You might want to remove the instrument cluster or tape it off, along with anything else that shouldn't have epoxy dripped on it.
Make sure the plastic, on both sides, is scuffed up anywhere you'll be applying epoxy. Now put some epoxy on the dashboard side and sit the pipes on it. Let it cure however long the manufacturer says and then start building up layers of epoxy to fill in the gaps.
Once you are satisfied that the pipes are securely bonded, remove your trim piece and set it on your workbench with the back of the piece facing up. Try to sit it down so it's not flexing much. By the time I got here the piece was much more rigid than it started. Fill in the back with more epoxy, but don't let it puddle up. Epoxy cures from heat created by an exothermic reaction between the two parts, if there are pools of epoxy, it can create too much heat and foam up, it can even burn you and could probably melt some plastics. Epoxies that cure faster create a higher temperature, and higher temperatures make epoxies set faster.
Step 6: Fiberglass Over the Pipes. or Don't.
Just mix according to the manufacturer's instructions and start building the shape you want. I used a large flexible plastic putty knife to smoothly transition from the curved front to the straight back.
Once all the layers of fiberglass were cured, I sanded it smooth. You'll want a P100 respirator for this, and a ventilation system is nice. I started shaping with a rotary tool and sandpaper drum, then a coarse half-round file to remove the machine marks from the rotary tool. From there it's all hand sanding unless you want ripples in it. I think I went down to 600 grit. Wrapping the sandpaper around dowels makes it easy to get in the corners. There were small pits left in the fiberglass, so I filled them in with body filler.
At some point over the first winter, the body filler and/or the fiberglass separated from the trim piece on one side. It's barely noticeable, just a slight shadow in the right lighting. If I ever did this again I would only use epoxy. It would take longer to finish it smoothly, but would be worth it to me.
Step 7: Paint It!
No photos here either. I was getting excited that it was starting to look better than I thought it would and I got in a rush to see it finished. I used SEM Plastic cleaner, adhesion promoter, and topcoat - mostly because someone on a forum said their "light gray" is a perfect match for the factory color. It's not even close (and the manufacturer doesn't state that it should be), but I like it better than the original medium-gray. If I had it to do over again, I'd probably use a cheaper paint.
Step 8: Install the Gauges in the Pods
The 2-1/16" gauges are slightly larger than the pipe's ID, so you'll need to trim the inside just a bit. I used a flap wheel on a die grinder. In hindsight, sizing the pods for the gauges before sanding and painting would have made me much less nervous while grinding with a power tool up to the edge of the paint. Just trim until they're a snug fit, mine can be pushed out with minimal effort, but I've had no problems in a diesel powered truck bouncing around on some rough roads, if mine haven't vibrated out, yours won't. Or maybe they will, I don't know. You could always use a set screw if you want.
Step 9: Wire Up the Gauges
Just follow the instructions with your gauges. Solder your connections! If you do, you'll never have a problem. Put some split loom over the wires and zip tie the wires to something so they don't bounce around and pull on the connections.
I kept the grounds for the gauges and the lighting separate so that I could install a dimmer on the lighting ground if I needed to. The grounds are on the bottom of the kick panel, very easy to get to and work on. I'm glad I kept them separate, the LEDs in the gauges are at least twice as bright as the instrument cluster lights and will be getting a dimmer soon.
Step 10: Find a Place to Run Those Wires Through the Firewall
There was a plastic plug right above the bulkhead connector. I removed it and drilled a hole in it to fit the grommet I had. I popped the grommet in the hole and ran the wires through the hole in the firewall.
If you're doing this on a SuperDuty truck, it sounds like they all have "customer access wires" as seen in the first photo - four wires that run through the firewall and are sealed off on both ends. Depending on how many wires you need to run, you might not need to drill a hole at all.
Step 11: Cut Your Wires and Install a Connector
If your gauges are on a part that will ever need to be removed, just cut the wires now to save yourself a headache in the future. With everything in place, you need to figure out where your connector(s) is/are going to go. Think about how you're going to remove it, make sure it's in a good position, and cut the wires. If you have gauges with the same wire colors on each gauge, you'll want to wrap the wires for each gauge separately and label them so you can match them up once you have them all bundled together.
Some gauges may be calibrated for a certain wire length, such as my pyrometer. I'd recommend not cutting these like I did, but I didn't read that until I was writing this Instructable.
Now slide the seals on the wires (if using weatherproof connectors, it's really unnecessary on the interior but I'd rather be safe than sorry), crimp the terminals on, slide them into the correct cavity, and snap the TPA clips on the back of the connector. Now make the other side match.
If you're using a mechanical boost gauge cut the tube for that too. You'll need a compression fitting to put it back together. Please don't use mechanical gauges for anything but air pressure, bringing hot, pressurized oil through the firewall is just asking for trouble. I hope it goes without saying to not run fuel lines through the firewall.
Step 12: Connect Your Powers and Grounds
You'll need to find a power source that's only energized with the key on. I got lucky again here, the Ford engineers put a switched power wire along with the 'customer access' wire bundle. The fuse panel is just numbered with no circuit description. I couldn't easily find which fuse fed this circuit so I just shorted the power wire to ground. I made sure the engine started and the transmission shifted with the fuse blown, and that no warning lights came on.. The blown fuse was easy to find, it was a 20 amp, so I replaced it and added a 5A ATC inline fuse using a MetriPack 480-series fuse holder. I could have used a 5A fuse in the main fuse box, but I didn't have any 5A ATM fuses, plus this way I have up to 15A more that I can draw on the circuit before I need to add a relay to B+.
Make sure you know what you're doing here, you could potentially start a fire if you don't use the right size fuse. If you tap a safety system like air bags, ABS, windshield wipers, etc., and the additional load caused the main fuse to blow while you're driving, you'll lose whatever system you tapped into. Find a system that you don't need - the radio circuit is usually a good one, but make sure it won't affect any safety or communication systems. I recommend staying away from 'fuse taps', they can cause high resistance which leads to heat which melts the plastic which loosens the terminals which causes more resistance which causes more heat... and so forth.
It wouldn't be a bad idea to fuse the wire feeding power to the lighting circuit, but there is a fuse before the dimmer. As long as the wires going to the gauges can handle the amperage the dimmer fuse is rated for, you probably don't need to add one. I checked the interior lights wiring diagram for my truck and found that it has optional accessories which would use at least three additional incandescent bulbs, and the one(s) for my 4x4 shifter is/are burned out and I have no intention of replacing it/them. I figure if I'm lacking at least four #194 incandescent bulbs, I'm good adding six #194 LED bulbs on the circuit. Again, make SURE you know what you're doing and what your vehicle is or isn't equipped with before adding on to circuits or making your own. Don't just copy what some guy on the internet did.
Step 13: Put It All Together
That's it. Connect your new connectors, reinstall your trim piece, and you're done - at least with the interior. You'll still need to connect the other end of the wires if you want your gauges to work, but that will vary so much from vehicle to vehicle and which gauges you want that I'm not even going to share what I did in this Instructable,