I am currently building a traditional inspired hot rod that will be sporting a fairly high revving engine. I want to keep it traditional looking except for maybe under the closed hood. My question is, has anyone ever converted an early dash clock into a tachometer? Essentially making a 12,000 RPM tach that looks like a clock. Maybe even with a shift light gem? Just tossing the idea around but really don't know where to start. I don't need 12,000, but will need more than 6. Trying to keep early 50s look outside. Thanks.
I don't know what you are building but I have seen plenty of old o rods with a tach stuck on the clock hole. I would think that if you just stuck a tach on the clock hole you would be fine but I am a form follows function sort of a guy so what is important is working well not looking well. Oh to answer your question no reason why you couldn't take your clock and tach apart and put the clock face on the tach. I would make myself some little marks on the clock face to I could tell where the needle points at target RPMs.
After inserting the tach into the clock housing, I'd been inclined to figure out where the marks needed to be and go down to a sign shop and get a vinyl sticker for the clock face with the right font, detail and colors to match your speedo. Should look good.
If you are handy with a computer you could scan the old clock face and rework it in Paint or Photoshop to make a tach face. Then print off a sticker. Find a tach the right size to fit your opening. Stick the new face on, and use the old clock minute hand for a pointer. Voila, a tach custom built for your car.
A sneak peek. A long ways to go before worrying about the tach, but searching for ideas. I suppose I could have somebody match the other gauges with a sticker. Just looking for something a little more subtle than a 5" monster tach with a shift light.
Not as easy to do as you might think. I did one for the '64 Comet I had. This was a on-the-top-of-the-dash unit that I modified to appear to be a 'factory' style (worked well enough that a collector offered me $500 for it... until he found out it was homemade... LOL). Changing the face was easy enough, but I found that any changes to the needle would throw off the calibration, even something as 'minor' as a bit of paint. I ended up buying another identical tach to use as my 'benchmark' to allow me to recalibrate the modified one, and I never did get it quite right. If you actually want it accurate, I'd recommend a professional conversion. If you do a 'sticker' overlay face, it may pay to have a pro laser print it on commercial vinyl. Most 'home quality' stuff will eventually blister/peel. As another thought, I'm going to try to install a shift light in the OEM speedometer face, no tach. A two-stage if I can find one...
The shift light should be easy and not need any type of conversion to the clock/tack. I would think that a mini light behind the hole where the original high beam indicator would go would work like a champ. If you have access to an old dwell meter with the tach option it makes it easy to calibrate a tach or at least check it for accuracy.
Oh, I am very open to the idea of having it done by a professional. I was just throwing this idea out there to maybe dig up a lead to see how outlandish it would even be to do. I am thinking an led shift light near 12:00 or replacing 12 with a red gem for the light. I won't need the needle to spin that far. 8-8500 at most. Small 4 cylinder with good flowing head.
There are instrument companies that do "vintage style" tachs and other instruments. One of them might be close enough to what you need.
The car had electronic ignition and you couldn't hook a dwell tach to it (didn't own one anymore in any case). I actually ended up buying two more tachs; one as the 'benchmark', and another to rob the needle pointer off of after I realized the modified one was the big problem. I painted the original pointer to match the OEM gauges, the weight of the paint threw the tach off by more than 20%! After getting a friend with a lab scale to carefully weigh the OEM needle, I then tried modifying that needle while keeping the weight the same (broke the first pointer, those things are fragile). That helped, but I don't think I got the 'weight distribution' exactly the same as it was still off a fair bit, but it was close enough that playing with the calibration got it pretty close...
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