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what are counter weights made of?

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#1 solshaker

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Posted 07 May 2009 - 03:47 PM

ive got an extra one sitting here from a celestron eq1 mount and want to bore out the hole to use it on an eq3. not sure what its made of and if a regular drill and bit would work or if i need to take it to a machine shop for some more muscle.

im guessing steel? :question:

#2 rwiederrich

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Posted 07 May 2009 - 03:58 PM

ive got an extra one sitting here from a celestron eq1 mount and want to bore out the hole to use it on an eq3. not sure what its made of and if a regular drill and bit would work or if i need to take it to a machine shop for some more muscle.

im guessing steel? :question:


Typically they are made of steel...some stainless.

If it is from an EQ1 it is probably steal and a good drill will do the job..or a boaring tool.

It's probably best to chuck it up in a lathe and drill it out that way...you may get a significant amount of drill vibration if you attempt it by hand. But I bet it is still possible. Where there is a will...there is a way.

Rob(my opinion anyway) :smirk:

#3 blueman

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Posted 07 May 2009 - 07:32 PM

There are a lot of them made from cast iron too. If it has a rough or texture surface, then it is probably cast iron. If it has a seam from casting then it is probably cast iron.
Blueman

#4 blueman

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Posted 07 May 2009 - 07:34 PM

Oh,
I did use a large drill bit in my drill press to bore out a couple of cast iron weights. Worked OK, but had to go slow and the cut was not perfectly smooth due to the cast iron, but it works fine.
I also had two bored with a lathe, that did a little better job, but not that much better really.
Blueman

#5 Rusty

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Posted 07 May 2009 - 07:57 PM

Cast iron is quite hard. If you have drills in the 1/64" steps, start with the smaller and work your way up. Actually, the same advice works for steel, with the typical hobbyist- type smaller size drill presses or portable drill motors - for a hole that large. Trying to do it by hand can be tedious - and dangerous - use low speed, oil, and look out for binding.

#6 Telescopeman54

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Posted 07 May 2009 - 11:14 PM

In the old days they were made from brass or lead! Ah, the good old days! (Siiiiiiigh)

Most of the ones with the rough finish are usually cast iron. A drill press, milling machine or lathe are the safest way to enlarge the hole. Cast iron must me machined DRY! Do NOT use oil or you could cause it to harden while drilling or boring.

The really good ones are made from SS. Those are obvious so we can rest assured that you don't have on made from SS.

Steve

#7 Doc Bob

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Posted 15 May 2009 - 06:23 PM

I had trouble finding an extra counter-weight for my CPC1100. . . apparently whenever I purchase something, it is immediately discontinued. It's a variant of the cloudy nights curse whenever buying scopes/equipment! I discovered that "zincs" supplied by boating supply stores are heavy, come in a variety of sizes and shapes, and are really easy to drill/bore-out, they are perfect sources of weight that are easy to adapt to our needs.

Hope this is helpful.
Bob

#8 mtb.daily

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Posted 15 May 2009 - 07:00 PM



I had four 11 pounders bored out to fit my new 1 inch shaft.

The machinist that did it told me they were all made of Cast Iron.

BTW: 2 were from my old ASGT and the other two were from my new Sky Watcher EQ-6 Pro.


He told me they were NOT EASY to do, but, as Rob said, when there's a will.....

-Jerry

#9 Luigi

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Posted 16 May 2009 - 06:34 AM

Stainless steel are nice but for the utmost in counterweight chic, you simply must have osmium :jump:.

#10 Nick-Sydney

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Posted 16 May 2009 - 08:04 AM

Sounds cheap :lol:

#11 Luigi

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Posted 16 May 2009 - 12:55 PM

As usual you get what you pay for, and in something a critical as counterweights you don't want go cheap. Buy the best and you'll never regret it. And think of the space savings! At twice the density of lead they'll be very small indeed.






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