VIDEO - Mach2 Right Ascension Belt Adjustment


Harley Davidson
 

Astro-Physics Mach2 Equatorial Mount Right Ascension Belt Adjustment
https://www.youtube.com/watch?v=2YMXr6ewAjs

This is a followup video to the vibration I had on my Mach2 mounts RA axis.

tony


M Hambrick
 

Another great video Tony.

Like you, I have always been impressed to see how A-P machines so many of their parts from solid aluminum bar stock. 

That cogged belt is also impressive. The part number indicates that it is a 3 mm pitch belt. What is the width ? I am guessing that it is at least 3/8" wide. That seems to be more than strong enough for the application.

Mike


Roland Christen
 


That seems to be more than strong enough for the application.
It's overkill for sure. It is designed for significant power transmission, so should never stretch or wear out.

Rolando


-----Original Message-----
From: M Hambrick <mhambrick563@...>
To: main@ap-gto.groups.io
Sent: Tue, Jun 1, 2021 6:34 pm
Subject: Re: [ap-gto] VIDEO - Mach2 Right Ascension Belt Adjustment

Another great video Tony.

Like you, I have always been impressed to see how A-P machines so many of their parts from solid aluminum bar stock. 

That cogged belt is also impressive. The part number indicates that it is a 3 mm pitch belt. What is the width ? I am guessing that it is at least 3/8" wide. That seems to be more than strong enough for the application.

Mike

--
Roland Christen
Astro-Physics


M Hambrick
 

I am going off topic a little bit here, but many of us who started driving in the 1970's will remember the introduction of these toothed rubber timing belts in automobile engines. Prior to this the timing was always maintained with chain sprockets.

Belt driven engine timing got a really bad rap in the US, and deservedly so because the US carmakers chose to introduce this concept on the really cheap cars like the Chevy Vega, Ford pinto, etc. The life expectancy of these timing belts was supposed to be about 30,000 miles. I was working as an auto mechanic in those days, and our shop saw a lot of cars come in with engines that had to be almost completely rebuilt because the timing belts broke while the cars were going down the road at 55 mph.

In the late 1980's a new type of hydrogenated nitrile rubber was introduced onto the market that was designed for use in hot, oily environments, and most of the timing belts were converted over to this new polymer. I think that Kevlar also showed up at about the same time. Now, most timing belts will last at least 100,000 miles.

Mike


Joseph Beyer
 

Interestingly the belt seems to be the astronomical mount equivalent as the drive belt on…Harley Davidsons.  Probably no relation.  The drive belts on the motorcycles have a service life of 60-100K miles.  My guess is the belt on the Mach2 lives in a much kinder environment and the life span will reflect it. 

On Jun 1, 2021, at 6:06 PM, M Hambrick <mhambrick563@...> wrote:

I am going off topic a little bit here, but many of us who started driving in the 1970's will remember the introduction of these toothed rubber timing belts in automobile engines. Prior to this the timing was always maintained with chain sprockets.

Belt driven engine timing got a really bad rap in the US, and deservedly so because the US carmakers chose to introduce this concept on the really cheap cars like the Chevy Vega, Ford pinto, etc. The life expectancy of these timing belts was supposed to be about 30,000 miles. I was working as an auto mechanic in those days, and our shop saw a lot of cars come in with engines that had to be almost completely rebuilt because the timing belts broke while the cars were going down the road at 55 mph.

In the late 1980's a new type of hydrogenated nitrile rubber was introduced onto the market that was designed for use in hot, oily environments, and most of the timing belts were converted over to this new polymer. I think that Kevlar also showed up at about the same time. Now, most timing belts will last at least 100,000 miles.

Mike


Harley Davidson
 

Thank you Mike!

tony

On 6/1/2021 7:34 PM, M Hambrick wrote:
Another great video Tony.

Like you, I have always been impressed to see how A-P machines so many of their parts from solid aluminum bar stock. 

That cogged belt is also impressive. The part number indicates that it is a 3 mm pitch belt. What is the width ? I am guessing that it is at least 3/8" wide. That seems to be more than strong enough for the application.

Mike


M Hambrick
 

Hi Tony

There was something else I noticed in your video that got my attention. Your counterweights have the bronze inserts in them. Are these older counterweights, or did you get them with your Mach 2 mount ?

Those bronze inserts significantly reduce the noise generated from installing and removing the counterweights.

Mike


Harley Davidson
 

You are correct Mike. They are the older design CW's.

tony

On 6/3/2021 10:02 AM, M Hambrick wrote:
Hi Tony

There was something else I noticed in your video that got my attention. Your counterweights have the bronze inserts in them. Are these older counterweights, or did you get them with your Mach 2 mount ?

Those bronze inserts significantly reduce the noise generated from installing and removing the counterweights.

Mike