Strobe Tach - anyone have one that I can borrow? GOT ONE COMING THANKS!

rv_safetyman · June 21, 2010, 06:55:31 PM

The charge air cooler saga continues. Have been working with the fan manufacturer and he has been a huge help. However, we are down to the point where we need to get a handle on the fan speed. The only way to do that easily is to use a strobe tach. I would buy one, but there is a huge variation in the quality of the strobe. I bought one for my consulting assignment in China, but the strobe was too weak to see, even in dim light. Good ones are well over $500 and I can't justify that.

If anyone has one, I will email you a UPS label to ship it to me and buy you an adult beverage (or two

).

Thanks, Jim

buswarrior · June 21, 2010, 07:03:49 PM

An optical tach is on my tool wish list.

Is that the same, or different from what you are looking for Jim?

Here at Big Transit, they put a tab of reflective tape on the 6V71 flywheel and it reads out the RPM when you point it at the piece of tape spinning past.

happy coaching!
buswarrior

luvrbus · June 21, 2010, 07:08:56 PM

Jim, I have a good Electomatic Tachometer that uses the tape it should work for you it is real accuracte if it will work give me a call at home.Sorry it not a China made but it is German made lol

good luck

rv_safetyman · June 21, 2010, 07:46:54 PM

Ewen and Clifford, I think we are talking about the same tool.

There are really two distinct types that I am aware of. There is the adjustable strobe light with a very powerful light that you can use to stop action. We used these a lot in our belt work to analyze belt and structure deflections. Worked on a John Deere cotton picker one time where they could not keep belts on. Took the strobe to their plant and we found that the structure went into oscillation under certain conditions and that would excite the belt to the point it would jump off the drive. These units have a frequency read-out that tells what the RPM is (you have to be careful, as it could be a harmonic). These units were quite large (sometimes a foot on each dimension), but they were a tremendous diagnostic tool.

The second version is what I think you guys are talking about. Much more portable and mostly for RPM only. The strobe is much weaker and thus they use the reflective tape. The strobe is too week to observe system dynamics, but that is not the issue here.

Clifford, I will call you tomorrow.

Jim

luvrbus · June 21, 2010, 08:02:04 PM

The one you are speaking about is called a stroboscope, my tack does have stop action

good luck

pato-06 · June 22, 2010, 04:57:21 AM

jim. i have one you can borrow. i can not remember if you are running a hydraulic powered fan. i had a real speed problem , until i got the oil temperature under control. would get less than half speed with hot oil. ( 15w40) Pat

rv_safetyman · June 22, 2010, 05:07:41 AM

Pat, thank you for the offer!!! I will contact Clifford first and see if we can work something out.

Good thought on the temperature. I have a large reservoir and I have "shot the temp." with my temp. gun and it was less than 150* as I recall. I will check it again. I am using Dextron (what was used in the PS circuit) and am beginning to second guess that decision.

Jim

boogiethecat · June 22, 2010, 10:01:04 AM

I've got one you can borrow and as you should remember, I'm in town....

gary

rv_safetyman · June 22, 2010, 02:33:09 PM

Gary, thanks for the offer as well. I assume yours was part of your "light show" at Burning Man

I contacted Clifford and his unit will be on the way shortly (just sent him a shipping label). That works out well, as we will be at the same rally next month (Eagle Rally in Custer, SD). I can get the unit back to him then.

Again, thanks for all the offers.

I am really working on this charge air cooler and I will not let it get the best of me

I did learn that I must have slept through "fan design 101" and "hydraulics 101" in engineering school. I have sure been getting educated over the past couple of weeks

Will keep you all updated.

Jim

luvrbus · June 24, 2010, 08:22:12 PM

Jim, it went out Wed do you need the tracking number

good luck

rv_safetyman · June 25, 2010, 05:26:29 AM

Hi Clifford. Thanks so much for the help!!!!

Since I created the label, I have the tracking number

. Scheduled to get to the Du Quoin Fairgrounds on Monday. That will work great! I insured it so that if Brown looses it, I can afford to replace it

As a side note, I am pretty sure that one of my issues with the hydraulic system is the Dexron I am using. I will start another thread for that discussion.

Jim