How hard is it to build a telescope?

[gooseholla]

What else can you do but laugh? In all fairness, I probably should have seen that as I was swinging to follow the moon, the right hand side was starting to tip and dig into the mud at a very strange angle - but you don't notice this in the dark when obsessing with why it won't collimate properly!

If I need a new mirror, so be it. Money is replaceable.
 

John

 

[mapstar]

Very true John and exactly how I think.

[gooseholla]

And if it is beyond repair.. couple of bits of 2x4 I'll have a nice coffee table

John

[faulksy]

What else can you do but laugh? In all fairness, I probably should have seen that as I was swinging to follow the moon, the right hand side was starting to tip and dig into the mud at a very strange angle - but you don't notice this in the dark when obsessing with why it won't collimate properly!

If I need a new mirror, so be it. Money is replaceable.

John

glad your taking it so well john, i wouldnt. i would sulk like a school kid for weeks hope you get it sorted soon mate

[gooseholla]

glad your taking it so well john, i wouldnt. i would sulk like a school kid for weeks hope you get it sorted soon mate

Last year a car blowing up within 3 days of buying it led me to be so stressed and emotional that I quit a decent job, lost nearly all my savings and ruined me as a person for months. I refuse to be ruined by objects and possessions any longer  So yeah, I am taking it well because I know how the other option ends for me!

John

[Peter Drew]

Sorry to hear this, however, for what it's worth, I've had bigger chips than that on mirrors with no obvious affect on the performance. You could be lucky and all you need to do is black out the area. 

[Moonshane]

Gutted for you. Hope it's only cosmetic

[gooseholla]

The top coating is still attached to the chip it knocked out. If the worst came to it, I could find a way to stick it back on and the damaged area would be very small, two little lines worth. But obviously if there is a way to fix it, I'm all for it.

Oh, for what's it worth, my review of last night's cut short moon viewing would have been its the best I've ever seen the moon and saw details I've never seen before in other scopes. The depth, clarity, and contrast were amazing. Obviously it was decided that I should have a reconstruction of Clavius in my mirror

John
 

[mapstar]

I recall a story that John tells of the McDonald observatory 107" scope which a disgruntled employee shot 6 times.

It made a mess but they bored the holes out painted them black and carried on using it.

There are several images on line.

Damian

[gooseholla]

I recall a story that John tells of the McDonald observatory 107" scope which a disgruntled employee shot 6 times.

It made a mess but they bored the holes out painted them black and carried on using it.

There are several images on line.

Damian

So that's why they discovered so many black holes...   :grin:  

[gooseholla]

Update this morning. When I go to the telescope making day at the end of November John will test my mirror. In the mean time I'll mask it off I suppose.  

John

[gooseholla]

So, we've had the news about the mirror breaking and some laughs about it, but now I'd like to share some things I have done to my shed, because apparently I have very little else to do now . The past 3 years it has gotten very moist in there and my telescope mirrors basically lived in permanent water. One of my scopes had part of its flip mirror eaten away by it. So this year I have done some things to try and aid it. First, the felt roof was in a bad way. I noticed the inside roof springing leaks and getting noticeably damp. I will re-felt it in the spring. For now, I put some waterproofing bitumen on, about £10 from wickes for a large tub. Makes the roof look nicer for a start.

Also, after reading around, the installation of vents in a shed with no windows seemed a good idea. So I have installed one  to let hot air out and one will be going in on the sides to produce an airflow.

Only a couple of quid  each and they can open or close and have bug screens. Bit of silicone around to waterproof the gaps. Takes all of about 3 minutes  to cut a slot and install. Hopefully these will improve things. I noticed this morning that the ground was dewed up and so was my car. Opening my shed the mirror wasn't dewed at all so fingers crossed it improves things until I can install a permanent heat source for the mirror.

Also, fed up of putting my scope away in the small hours of the morning and hearing THUD THUD THUD CLUNK across the wooden floor so experimenting with some of that antinox floor protection stuff. Seems to make a huge difference to the thudding noise. Hopefully that will keep neighbours happy!

John


 

[mapstar]

Nice update John and glad you've made the scope a great home.

Interesting mods and maintenence to make it more suitable. I'm not sure where I will be storing my scope once it's finished? I also have a shed too which is small and would fit the bill it would need a few mods to make it suitable.

Damian

[Soupy]

Gutted about the mirror John, but as you say it's a possession that can be replaced Great outlook, hopefully John can sort it out. Will look forward to seeing it at the seminar! And nice mods to the shed

[Soupy]

Not in a morbid fashion I might add!

[gooseholla]

Not in a morbid fashion I might add!

If I hear a sinister "muhahahaha" from the back row when you the missing chunk is revealed, I'll know its you

[gooseholla]

El Goosey's guide to heat shrink wrapping poles

Today I used the heat shrink I purchased to wrap my poles. It is about 50mm when flat making it easy to slip on to the poles. After much trial and error, I got the knack of shrinking it nice and smooth leaving little to no wrinkles to go back and sort out. I'll call it the 2-2-2 method...

First, you need a heat gun or something similar and something non-flammable to raise the poles off the ground. Cut your heat shrink to the desired length - it will shrink a bit - and then place it where you want. Now, the best way I found to do it was to hold the gun at a slight angle about two inches above the pole and about two inches behind where the shrinking is occurring for about 2 seconds, or a slow two count, before moving on a bit. You want the shrinking to occur nice and slowly but continuously and evenly shrinking on both sides. If one side is falling behind, move the gun to let it catch up then return to the top. When you reach the bottom you should have a nice smooth finish and if you turn it over hopefully only a couple of wrinkly parts at worst to sort out by holding the gun over that area for a few seconds.

Oh and don't touch the poles, they will be hot for a while!

John

[gooseholla]

Tonight is meant to be clear so I am going to test my telescope out to see what affect there was on the mirror.

I have been playing about with the sling mechanism and I believe I had found the problem. The mirror posts have a flat face that faces the mirror the rest is curved. I think one of these was loose and spun around trapping the sling between the mirror and the curved part post causing the mirror to lift off of the floating triangles. Hopefully will see if this solves it, although I am going to have to make three new posts after last week. Will be making them a little thinner I guess and out of sturdier material.

John
 

[mapstar]

More work John and all good stuff.

I applaud your enthusiasm after the mishap with the mirror and let's hope it still provides great views.

I am going to try self adhesive Velcro on the side of my mirror with straps to the back of the box just for some form of reassurance. Should work?

Damian

[gooseholla]

Yeah hopefully would work. That stuff can be hard to rip apart at times! I'm thinking of adding some kind of foam around the tailgate edges and something soft over the nuts just in case it happens again! But hopefully sturdier mirror posts will mean it can never snap them and fall down in the first place. Stupid wood...
 

 

[gooseholla]

After viewing a couple of stars in the summer triangle at low and high power there doesn't seem to be too much wrong with the scope after its accident. I am trying to chase down whether I am seeing a slight mis-collimation or there is an extra little point of light forming on the side of stars due to the mirror (it is forming on the side where the chunk is missing!). Will hopefully hunt that down throughout the night as I tweak the collimation. The real test will come on something big that fills much of the image when dark. Then i'll know what the true damage is, if any. Hopefully got lucky!

John

[Soupy]

Fingers crossed it's caused minimal issues John. Sounds promising though.

[gooseholla]

Defeated by clouds but did get to look at Andromeda - that fills enough of the eyepiece. Didn't notice any problems. Saw faint galaxies no problems and detail within Andromeda, so I think I may get lucky and just have a cosmetic damage. I'm sure John's tests will reveal how much or little has been lost, but at the moment I can continue using the scope with no problems it seems.

Although a bright object like the moon will probably be a better test for scatter etc.

John

[mapstar]

Sounds good John and it's not affected the views much if anything.

Are you going to paint the chipped area black, shouldn't make much difference to any remedial work as that would probably involve a re-grind?

Damian

[gooseholla]

Knowing my painting skills I'll end up with a black mirror!