Posted 02 November 2012 - 09:20 AM
Posted 02 November 2012 - 03:05 PM
Elastomers aren't true springs, and change properties with temperature. A lot of the "ETX works" would appear to be not asking much from it
Fully agree, but i was just answering Eds comment re how the ETX worm was preloaded. In reality, the ORing method is not very "responsive", but it does "ooze during operation" thus keeps the gears in contact.
The main point of the piccy was to show a low pressure angle worm could be made in the sizes we were discussing.
Posted 03 November 2012 - 12:03 AM
I'm with you there. Going from the way the details are designed, I can't imagine the same engineering authority was behind all of these designs. What does that mean? I'm really not sure. The LX80 has been profoundly difficult to account for.
Posted 17 November 2012 - 07:32 PM
Posted 18 November 2012 - 11:50 PM
Posted 19 November 2012 - 10:34 AM
Regarding the mount, I tested it at DSRSG a few weeks ago. Rod Mollise was there and has commented on what he saw on his new blog. Its contained in his report of the DSRSG. His blog can be found at:
If anyone is interested in getting a tripod top replacement, contact me directly.
Posted 09 December 2012 - 03:25 PM
I've read all the LX80 threads and was concerned about the lightweight tripod top. Also, upon first inspection and use, I sort of thought that this particular LX80 might not have much of the AZ slop being discussed.
Thus, in order to avoid a tripod failure and to try and gain some tripod stability and minimize vibration, I asked a machinist friend to make a beefier top.
Here's our version the LX80 tripod top:
The top is billet aluminum and the leg lugs are steel. The dull finish is from bead blasting.
The new top width is the same width as the attachement bolt posts on the OEM top. The allen bolts are about 2 1/2 inches long.
The little hole by my thumb is for the OEM bubble level; LOL...
The new top basically has the same dimensions as the original top.
Although the center rod attachment lowers the tripod spreader triangle a little, it still fits fine.
Everything assembles perfectly using the homemade top.
Inlcuding counterweights, the above is about 50 pounds or so.
My only use is visual and outreach. Although I've used the LX80 several times in alt/az, I have not set it up in EQ yet. Last night was the first use with the new top.
The new top definitely removes any worries that a leg might break away. But maybe there was only slight gain in overall vibration removal, if any.
To be honest, last night was the first time I really checked the LX80 az slop being discussed in the other thread. I now better understand the issue but am not really worried about it since I am visual only.
Anyway, I wanted to share my solution to the LX80 tripod top weakness. Before I asked my friend about machining a new top, I was going to install small diameter tie bolts on the OEM top for increasd strength and fill the whole underside area with epoxy resin.
So far, I like the LX80 because it is relatively easy to set up and I like Sandy Wood LOL... Next I will try the EQ configuration to see how stable that is.
Posted 09 December 2012 - 03:32 PM
Thanks for the information. That top is nice looking. Is your friend interested in making any more? If so, let us know the price.
Posted 09 December 2012 - 09:27 PM
I noticed that when I added the replacement tripod top that my machinist developed, the mount was more steady than with the stock top. But some of that may have come from not having to fear overtightening the spreader and having a leg snap off. If you are going to use the LX80 for purely visual observing, you may find it satisfactory in Alt-Az mode. The damping time for mine when using a C9.25 was about 5 seconds if I tapped the diagonal. I don't know how heavy your refractor is, but it's longer than my SCT, so it may result in slightly higher vibration. My damping time doubled when I set the scope up in EQ mode.
Posted 09 December 2012 - 10:00 PM
Posted 10 December 2012 - 12:09 AM
I do not have an exact damping time yet because the wind was a little breezy. So really, my previous comments regarding vibration are very loose because the wind was enough to affect the dampening. In fact, the wind eventually ended the session.
The material thickness behind the bolt head is about 3/16" - 1/4" or so. i do not have the exact measurement. We were going to make it thicker by cutting a deeper notch into the disc and leave more material on the back side of the U. But that extra material was not necessary to attain the strength needed. The bolts will never pull through in any scenario in this application. Interestingly, this specific aspect was discussed several times to ensure it would be enough. Another option we were considering was to remove some material off the front of the bolt head and having a shallower cup.
Unfortunately, there are too many other projects in the que to make any more of these at the moment.
I will try and get some dampening times the next time out.
Posted 10 December 2012 - 08:06 AM
At the last star party I was at with the LX80 and C9.25, I did notice the scope being shaken by light breezes while in EQ mode. It was enough to wash out any detail visible on Jupiter. The view of Jupiter was much better in A/A mode as the damping time was 50% less.
My load on the mount was the 22# OTA and I was using a 22# Celestron counterweight.
Posted 12 March 2013 - 05:20 PM
Posted 12 March 2013 - 06:26 PM
Toothcount wise, the LX80 is the same as an LX90
ie 154 teeth
Andrew Johansen Melbourne Australia
Posted 13 March 2013 - 03:13 AM
I know that the hand controller has a selection for cable snag, but I don't know what that does or how it works. I just enabled it as an assumption that it offers some sort of protection. Does any one know for sure?
Posted 13 March 2013 - 03:32 AM
There are NO internal fuses,
ie if you fry, you die with a Meade scope.
No it doesnt, it has a "cord wrap" function
I know that the hand controller has a selection for cable snag,
but I don't know what that does or how it works.
Cord wrap ON merely limits how many revs the scope will go one way or the other in RA when doing a goto.
It provides NO protection against cables getting caught whilst in the allowable slewing regions.
Andrew Johansen Melbourne Australia
Posted 13 March 2013 - 06:30 AM
Posted 13 March 2013 - 09:34 AM
Posted 18 March 2013 - 09:17 PM
Posted 19 March 2013 - 08:05 AM
So I will be doing some experimentation with amperage loading soon. I am going to figure what fuse it will take to protect the thing from physical damage. Has anyone done this already?
I'd be awful careful with that.
As above, that's not the purpose of a fuse. May save the gear, may not.
Posted 28 March 2013 - 03:06 PM
Posted 28 March 2013 - 03:08 PM
Posted 28 March 2013 - 04:16 PM
Posted 28 March 2013 - 05:35 PM