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-   -   Speed Warning - Back from the Dead (https://67-72chevytrucks.com/vboard/showthread.php?t=642702)

davepl 09-09-2014 08:46 PM

Speed Warning - Back from the Dead
 
1 Attachment(s)
I bought a speed warning cluster from member John H a couple of weeks back, then promptly destroyed it because I took the needle assembly too far apart. I know masking isn't perfect, but if you find yourself in this position, mask it, don't blow it apart.

Anyhow, TBONE the gauge specialist member was a huge help. First he had a spare needle assembly. I almost ruined that one too because I wanted to airbrush the needle... so I took it apart, just not as far. Take my advice, having done it twice: don't take it apart. I managed to get it painted and back on, but I have literally days into it.

Anyhow, the odometer was all yellowed. Tried to clean it without success, so I decided to transfer my original over. For some reason internally I discovered the thousands digit was locked at 6. And indeed, the truck has 76XXX miles on the odometer. I bet it just stuck at 76K and wrapped around perpetually every 1000 miles.

Tried to take that apart and fix it, but could never find the problem. I decided to then pull an odometer out of my Pontiac stash. Had to shorten the shaft a little but otherwise seemed to interchange. The little plastic retainer had shattered but I didn't need to make a new one because this speedo head has the full rail for each odometer digit tab (some have a gap for the thousands and rely on the plastic thing).

Sadly, when I pulled the face of the speedo all 6 little gears for setting the speed warning and some shims fell right out, as they're actually retained by the face. TBONE to the rescue again as he was able to send me a photo showing the correct gear layout.

Once back together, I found the speed warning aspect didn't actually work. Just oxidation after all these years I guess, as I was able to clean up the spring contact with some laquer thinner and use some emory cloth on the pin of the speed warning needle contact and now its consistent and accurate.

So, long story short, I'll soon have it done. I'll post a photo of the whole cluster eventually. In the photo it looks like the base of the yellow needle is unpainted or a different color, but it's just the angle of the photo.

TBONE1964 09-09-2014 09:10 PM

Re: Speed Warning - Back from the Dead
 
Always glad to help Dave. I am happy you got it back together and functioning properly.

By the way, that is the nicest speed warning face I have seen in a while. They are extremely hard to find in that condition.

Looking forward to photos of the complete cluster.

Great work there,
Tom

Andy4639 09-09-2014 09:26 PM

Re: Speed Warning - Back from the Dead
 
Looks like you gotter done man! Good job. I had mine done by TBONE1964 great job on the cluster.:chevy:

davepl 09-09-2014 09:42 PM

Re: Speed Warning - Back from the Dead
 
Does anyone (TBONE?) know how sensitive these are to the added weight of repainting them? This needle assembly in particular seem to have an counterweight balance. If that counterweight's mass was calculated based off a weight that I've now changed, I wonder how much, if any, it'll affect its accuracy or linearity.

TBONE1964 09-09-2014 10:14 PM

Re: Speed Warning - Back from the Dead
 
1 Attachment(s)
Quote:

Originally Posted by davepl (Post 6836958)
Does anyone (TBONE?) know how sensitive these are to the added weight of repainting them? This needle assembly in particular seem to have an counterweight balance. If that counterweight's mass was calculated based off a weight that I've now changed, I wonder how much, if any, it'll affect its accuracy or linearity.


Hi Dave,

I don't the very little bit of paint you use on the needle will cause an inaccuracy but you do bring up a valid point and it is possible that paint build up on the needle will throw of the calibration of the speedometer.

Here is a little tool I use in my shop to confirm speedometer accuracy. Now that you have asked, I need to do an experiment with a known accurate speedometer and pile on some paint and see what happens. It will make it slow if anything.

Not sure when I would have time at this point but I will do a test in the future.

I use this tool also for each and every gauge cluster I sell to insure accuracy, no noise and no needle bounce.

Hope this helps.
Tom

jabborabbo 09-09-2014 10:19 PM

Re: Speed Warning - Back from the Dead
 
Quote:

Originally Posted by TBONE1964 (Post 6837009)
Hi Dave,

I don't the very little bit of paint you use on the needle will cause an inaccuracy but you do bring up a valid point and it is possible that paint build up on the needle will throw of the calibration of the speedometer.

Here is a little tool I use in my shop to confirm speedometer accuracy. Now that you have asked, I need to do an experiment with a known accurate speedometer and pile on some paint and see what happens. It will make it slow if anything.

Not sure when I would have time at this point but I will do a test in the future.

I use this tool also for each and every gauge cluster I sell to insure accuracy, no noise and no needle bounce.

Hope this helps.
Tom

Just out of curiosity...where did you get that fine piece of test equipment?

TBONE1964 09-09-2014 10:49 PM

Re: Speed Warning - Back from the Dead
 
Quote:

Originally Posted by jabborabbo (Post 6837014)
Just out of curiosity...where did you get that fine piece of test equipment?

I actually bought it from the speedometer shop that is here local to me in Michigan. Scott Speedometer Service. They have been in business for over 60 years. I got to be very good friends with the owner over the years. The business would buy equipment from other speedometer shops that were going out of business.

I feel lucky to have it as they are getting harder to find. It did not come cheap either ;)

jabborabbo 09-09-2014 11:02 PM

Re: Speed Warning - Back from the Dead
 
Quote:

Originally Posted by TBONE1964 (Post 6837057)
I actually bought it from the speedometer shop that is here local to me in Michigan. Scott Speedometer Service. They have been in business for over 60 years. I got to be very good friends with the owner over the years. The business would buy equipment from other speedometer shops that were going out of business.

I feel lucky to have it as they are getting harder to find. It did not come cheap either ;)

I'll bet it wasn't cheap...cool piece of test equipment!

John H. 09-16-2014 01:54 AM

Re: Speed Warning - Back from the Dead
 
Dave,

Excellent work! That cluster came from AZ, so I thought it would be in good shape minus the fading. The speed warning needle should be a pale yellow. I should have taken pictures of the nos one I had.

I am right behind you on the cluster I am building.

I need to get the other part of the cab puller.


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