No 56k: Massive Instrument Cluster Update
No 56k: Massive Instrument Cluster Update
So, this is going to be a long one, and very picture heavy.
I'll start with what I did just after making my last big post on the topic, with a small issue the Fairlane had, unrelated to the instrument cluster.
The Fairlane was due for inspection and registration renewal that month, and the horn was no longer functioning, so I had to fix that before I could get new tags for the car.
I started by pulling the steering wheel and trying to find out how the horn was supposed to work. This meant pulling the wheel assembly to pieces.
First up, this is what the end of the column looks like, fairly standard 1960's Ford:
You can see two brass contacts on the right side of the column. One of these is a +12v hot feed, and the other runs to the horns which are grounded through the chassis. Bridge these contacts, and the horn sounds. That much of the system was functioning as designed, so I determined that the issue was in the wheel itself.
Now the wheel assembly consists of 8 major parts, the wheel itself, the horn ring, two metal contact rings, and a plastic insulating ring, two brass contacts, and a plastic decorative ring.
The back-side of the wheel:
The metal contact rings and insulating ring assembly:
And the exploded assembly:
When you press the horn ring, the bottom of it would touch one of the two brass contacts (both wheel-side contacts are attached to the same contact ring) and the top of the horn ring would touch a metal post that is sticking up from the larger ring.
I was able to determine that the post sticking up from the larger contact ring was no longer making contact with the horn ring.
Unfortunately, I was not able to bend that metal post into such a position that it would only touch when the horn ring was pushed, so I chose to go with an alternate solution, and install a horn button into the wheel. Connecting the horn button to one of the wheel-side brass contacts was easy, just a simple ring terminal, but it was more difficult to attach the other side to the metal post. I ended up soldering the wire to the post, and putting a connector in. A few plastic washers and a nice horn button later, and I had a functioning horn once again.
Now, on to what you're really here fore, the custom instrument cluster:
With the waves pressed out of the casting, the cracks welded up, and the casting heat-treated and aged, it was time to start milling it. I put the casting into the schools HAAS Tool-Room mill with the intent of creating a few flat spots to use as datum?s while dialing in the cluster in later processes.
I dialed in the part using the top and back of the "legs" to zero it out, and ran a single pass along the front of it:
As you can see, it cut deep on one side, and not at all at the other. I stuck a dial gauge into the mill, and determined that the entire casting was twisted along all 3 major axes, as well as pretty much any and every imaginary axis you could imagine... I was going to have to take a lot of material off...
I dialed it in about the "Z" (up-down) and "Y" (forward-back) axes as best I could (ended up being +/- .050) and cleaned up the bottom and lower-front surfaces.
I then wrote a quick program in MasterCam X7 to use a 3/4" ball end mill to rough in the 45? angle along the front face. The first pass would have ended up taking way too much material in places (perhaps as much as 3/8") so I had to move the Z-Offset up more than .300" and take multiple passes to get the surface even remotely cleaned up. The program ended up taking a full 7 hours just to run, with me standing next to the mill the whole time, manually brushing coolant onto the part.
Looking back on it, I should have run the whole thing on the schools other mill, which is an enclosed coolant machine, but when I put the part onto the Tool-Room mill, I thought I was only going to mill some datum?s into it, before moving onto the bigger machine.
Once I started though, there was no stopping till I was done roughing in the front face.
Finished roughing it in:
Once I had the front roughed in, it was time to mill the details into the back. I pulled the part out of the Tool-Room mill, and used the schools equipment to try and measure the offset on the front. This was necessary so that I could create some notched soft-jaws to hold the part securely in the other mill.
With the custom soft jaws made, I put the part in the mill, and set up the 8 tools I would need to run my program. I would start with a 1" roughing end mill (the brass one) to remove some extra material towards the outsides, before moving to the professor's personal ($800 :shock: ) 3" facing mill to face the back. Next up was a long 1" end mill to open the gauge holes to the final diameter, then back to the 1" roughing mill to make the pockets around the gauges to for the gauge bezels to sit in.
Then a 3/8 end mill to create the pocket for the HVAC lighting panel and the viewing slots for the same.
Finally, the spot drill, 5/8 drill, 5/16 drill, and 3/8-16 tap for the warning light holes (5/8) and the mounting holes (3/8-16)
With the tools in, and the offsets set, I simulated the program on the controller one last time:
And pressed the scary green go button from which there is no return:
Ends cleaned up:
First depth on the facing:
Time to mill the gauge holes:
And done:
I had to re-run the first two tool-paths (the cleanup and the facing) several times at different Z-depths (.050 at a time) till it cleaned up enough of the back to be happy with it, and then I had to stop the gauge bezel pocket toolpath early, before it could run to the full programmed depth, otherwise it would have milled right through the part in places. (That web at the bottom was quite a bit thinner than I designed after cleaning up both sides of it) This caused me problems later of course, but it couldn't be helped.
Inspecting the part that evening. It was 5 full days of milling to get to this point:
Then it was back to the mill to clean up the front side.
This was a rough one to dial in, but eventually, I got it in.
With the part oriented this way, I "manually" milled this surface with the 3" facing tool using the handle-jog mode on the mill.
Then I rotated the part 45? to do a final clean on the bottom edge.
Dialing it in:
And finally I rotated the part again, and cleaned up the outside border (no pics, it was late and I was in a hurry to finish before the shop was closed)
With the outer border cleaned up, the milling process was officially completed for the bezel:
I never could clean up that spot on the front between the two big gauge holes. I would have had to go too deep to take that out, but I was hoping that with some sanding, sand-blasting, and more sanding, it would be less noticeable.
I also could not go deep enough when I was facing this back side for this corner to clean up, not without making the bottom web even thinner than it already was. Enough of the back was surfaced flat to make this irrelevant though:
The final milling processes on the front revealed some additional casting flaws, but again, nothing I could do about them now other than accept them and call it "Character"
.
With the milling done on the bezel the next step was to take the part over to Agrinautics, the same company that helped me out with fixing the waves in the casting, as well as heat-treated it for me, and media-blast the part in their blast cabinet.
No in-process pics, but here it is finished:
I then used a red scotch-brite pad to scuff the front surface, and give the bezel the finish I wanted before clear-coating it with a satin clear.
At this stage, the bezel was 100% complete, and it was time to turn my attention to the mounting clamshell.
I hand-cut the clamshell out of 16 gauge steel using a cut-off wheel for the outer profile, and a drill-press with a 2" and 3" hole saw for the gauges. I used a Uni-Bit (step drill) for all the smaller holes. I located all the cuts using an Engineering Mylar that I printed out at work.
With the profile cut, I put the part in the schools sheet metal brake, and put in the necessary bends.
I attached the clamshell to the bezel, and put the whole assembly back into the mill so that I could open up the gauge holes to the final size & location.
And the cluster was, more or less, done!
All that remained was the installation.
I started the install by match-drilling and clearancing the clamshell so that it could fit into the car:
Trial run with the speedo, indicating that some clearancing of the car was also necessary:
Of course, I couldn't resist sticking the bezel in
I also customized the 4 nuts that go onto the studs protruding from bezel. I used JB-Weld to attach some collars (made from an old aluminum tube I had around) The collars make it easier to start the nuts on the threads, as well as offset the nuts away from the clamshell for the one stud that is around the cluster of warning lights. Necessary because around those warning lights, there is not quite enough room for the nut.
Then it was time to wire up the cluster. This took an entire day, just to make the harness. I created a wiring diagram in AutoCAD, and had all the pins and connections mapped and laid out, so I was just a matter of the grunt work to put the plans into effect. Not shown is the Molex Mini-Fit Jr 20 pin connector (the same used on older ATX motherboards) that went on the end of that harness, as well as onto the car side of the harness.
That was a long day...
Now, remember where I said that I couldn?t mill the gauge bezel clearance pockets deep enough and that it would cause me problems later? This is where those problems really came to light.
Because those pockets were not deep enough, the bezel was not sitting flush against the clamshell. I had used some jam-nuts at the base of the 4 studs to even offset the bezel the correct distance, but this caused there to be a 1/4" gap between the bezel and the clamshell.
For the most part, this is not an issue. The LED lights that I am using, due to the nature of their design, sit deep enough into their holes that light leaking out around them is, more or less, a non-issue.
But, around the HVAC panel, which has a LED packed sheet-metal reflector on the back side of the clamshell, and a panel inserted into the bezel, there was an issue.
That 1/4 gap was allowing a massive amount of light to leak out from the reflector into all the warning light holes, Not good.
My solution was to create a foam filler (attached to the clamshell with RTV silicone) to block the light leak.
Ugly, but you can't see it, and it's effective.
The last thing I had to do was run my wires to the signal senders for the various gauges. Doing so also instigated me to clean up my under-hood wiring harness. The routing is much cleaner now, and all I need now is some harness tape or other method of covering the harness.
And now it's finished.
W/O Dashpad:
W/ Dashpad:
Some last thoughts.
I love it.
This thing is so cool to look at while I drive, and though I don't have any pictures of it yet, the night illumination is flat out sexy.
That big high quality tachometer is a delight to watch dance around, and visibility on the other gauges is acceptably good while driving. The nature of this design does occlude the visibility on the gauges a fair amount, but that is an acceptable price to pay for something so very sexy.
All the warning lights work, and it's an novel experience having a light that tells me the engine is cold (an OEM functionality, but the wire was broken before I bought the car, so it's never worked before)
The LED turn signals are obnoxiously bright though.
Also, I was not able to install the sender for the oil temperature gauge (last one on the right) due to not having anywhere to put it.
I am trying to decide between buying an in-line oil filter adapter designed to feed an oil cooler and routing my temp sender into that, or waiting until I buy a baffled Road Race oil pan, most of which have oil temp bungs in them.
I need the road race pan anyways, since under... Enthusiastic driving shall we say, I tend to loose oil pressure.
I could also drill a hole in my current pan and weld a bung onto it, but I am concerned about doing that in-situ, and I really don't want to pull the engine again so soon.