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How hard is it to build a telescope?


gooseholla

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Yeah just got to make some split blocks or buy some pre-made solution. Also waiting for focuser to come still, so still a wait until I can test them.

Was exciting when it turned up at last. :grin:

John

How lovely it looks and a fine piece of craftsmanship. I wish mine was at the same stage ie finished!

Looking forward to seeing the whole scope together John

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Split Blocks

Today I made my split blocks. They are a compromise to get me going. I intend to order the Webster Telescope solution in the future. This job has been tough. I have bought a variety of drill bits that didn't do the job and two bits of beech as the design changed. I must admit it has taken more time, effort and money than I would have liked, but still well within my budget.

They were drilled out using a hole saw at 900RPM on my drill press. The saw just flew through them like a hot knife through butter. Everything else I tried didn't make a hole, blunted or got stuck instantly.

The assembled one is a prototype. I have to go and cut some better slots into the rest. They aren't the size the book suggests due to my drill only being able to do this size of material. As I said, I hope to upgrade them in the near future. I'm not entirely happy with them, but onwards to the next task. I shall be ordering a pre-made Spider from America at the beginning of next week I think as I don't think my designs are going to be good enough. I also have to build the rocker box and wait for my focuser to come. So going to be a bit of a delay until first light.

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I have learned a lot doing these though, and thank you to Mapstar for all his suggestions.

Regards

John

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Today's task wasn't romantic but it needed doing - three mirror posts were made. I found some really cool hooks under the stairs with three pins in so I thought it would be rude not to use them! The posts will be painted black and the hooks wrapped in self-amalgamating tape.

Also cleaned the pole holders up a bit and tested each of them. Planning what to do next now. It is a tough one as there is little I can do without a spider or focuser at the moment.

I think a lot of sanding and putting final coats of varnish on things is about the only task for the near future.

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John

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Progressing quickly, and in the back ground looks like you've managed to finish all the truss pole clamp slots. Are you drilling the opposite end for mounting screws to go on the box? 

Varnishing and finishing seem to take ages, in my case I always seem to find another bit I've missed or forgot!

I take it John also sent you an appropriately sized secondary with the mirror? 

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Yes he did. I didn't take a picture of it but it is wrapped up in the box.

Yes, the coach bolt will go through the mirror box as they suggest in the book and then when in the correct position two drywall screw will go in the other end.

John

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Look nice John. I can endorse fully the Webster truss components, simply superb. they grip the tube like an angry pit bull :)

As far as I can tell Webster truss clamps (lower) are identical to "Rhino truss clamps" (easier to buy here in the uk) , e.g. http://www.ebay.co.uk/itm/4-x-Rhino-Lighting-Multi-Clamp-Truss-T-Bar-Lighting-Clamp-/271226822551?pt=LH_DefaultDomain_3&hash=item3f2660df97

No experience of Webster ones but I did buy a couple of Rhino clamps a while ago and they're very strong. 

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As far as I can tell Webster truss clamps (lower) are identical to "Rhino truss clamps" (easier to buy here in the uk) , e.g. http://www.ebay.co.uk/itm/4-x-Rhino-Lighting-Multi-Clamp-Truss-T-Bar-Lighting-Clamp-/271226822551?pt=LH_DefaultDomain_3&hash=item3f2660df97

No experience of Webster ones but I did buy a couple of Rhino clamps a while ago and they're very strong. 

Wow, thanks for that link. Silly question, how would they install on to a mirror box - drill a couple of new holes through the plastic?

I think I'm an idiot - presumably it is with the bolt and wing nut already on there?!

John

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There's already a bolt you could use to mount the clamp on a mirror box - with the wing nut on in the pictures.  You can remove that bolt and swap it for a longer one if needed, so  you'd just need to drill a hole through the mirror box side and bolt it on.  Reading Webster's description they say its angle is adjustable so it sounds like they just have the single bolt to mount it.  

   

John

edit: that bolt with the wing nut on is strong enough - it's not just stuck on to the outside.

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As far as I can tell Webster truss clamps (lower) are identical to "Rhino truss clamps" (easier to buy here in the uk) , e.g. http://www.ebay.co.uk/itm/4-x-Rhino-Lighting-Multi-Clamp-Truss-T-Bar-Lighting-Clamp-/271226822551?pt=LH_DefaultDomain_3&hash=item3f2660df97 No experience of Webster ones but I did buy a couple of Rhino clamps a while ago and they're very strong.

They certainly look similar, very tough indeed. :)
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Just an update:

Moonlite Focuser is coming tomorrow.

Had to go down the timber yard today, stupid me forgot to compensate for the thickness of plywood so mirror box was too small in one direction. D'oh. I suspected this earlier in the build and mentioned it might be a factor. No loss - bloke undercharged me quite a bit so got it at a bargain price, pre-cut so just have to glue it all together and varnish.

Measured up for the spider I need - 19.5". Will be placing an order with Astro Systems today or tomorrow. Then that will be the only thing holding up testing it to measure for the truss poles. I think though testing it on Virgo/Coma clusters is out... Summer clusters it is :grin:

John

 

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Hi,

A quick question. On a secondary front, the MA is 3.5" and length wise it is 5". How much or little would be needed diameter wise for the 45 degree stalk it attaches to? 3.25" is probably the maximum, but does size matter, or is the silicone going to hold it on pretty much any size piece? I am actually thinking of giving the spider one more shot, using a design someone sent me that I forgot about.

Regards

John


 

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Well today my Moonlite focuser turned up! :grin:  :grin: Two huge boxes full of packing material for a tiny  focuser!!!

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I originally chose orange, as that is my favourite colour but Moonlite haven't shipped them to FLO yet so I went with red.

Also the second attempt at a mirror box is drying. They didn't do such a good job cutting the pieces this time, but it is tolerable.

Tomorrow I hope to be able to re-measure for the side bearings and attach them, then start on a spider again. I have a design in mind and think I can achieve it over this weekend. Then If the spider works next week I can think about testing the mirrors to measure for the truss poles - once any sign of saw dust has been removed from the assembly area of course!. Also got to sort out getting some sides cut for the rocker box and getting some semi-circles cut into them.

John

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A very lovely looking bit of kit I bet your well happy with it.

Looks very nice in the Red too. I'm also looking forward to seeing the next spider come together

Keep up the good work we're all here spurring you on

Damian

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A very lovely looking bit of kit I bet your well happy with it.

Looks very nice in the Red too. I'm also looking forward to seeing the next spider come together

Keep up the good work we're all here spurring you on

Damian

It is quite a heavy item but well built and smooth. Nothing like any other focuser I have owned.

Yup I will unashamedly be going with rustysplit's design you sent me a link to and I had forgotten about until two days ago.

John

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Today was a lovely sunny day so I took full advantage of it. Paint brush in one hand varnish brush in the other. The inside of the new mirror box is now matt black and the outside has had two coats of varnish. Just got to do some touching up tomorrow then I will install the tail gate and side bearings into this one. The mirror posts were also painted black. Then it will go in the safety of the shed whilst I cut some plywood up to make the spider. Hopefully then I'll be in a position to at least test the scope in the next week or two. :grin:

Jobs left:

-Spider

-Focuser board to cut down and install focuser on

-Rocker box sides to cut

-Drill a hole through rocker bottom and ground board for the pivot bolt

-Order some formica and install it onto the bearings

-Touching up and fiddling with bits/tweaking.

I think the way things are going, the first test will be without the rocker box built. But in some ways I think that it would be superfluous for testing the scope to measure for the poles anyway.

John
 

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A question - can I use my exterior varnish on the Beech blocks or is there something better?

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Today some good progress was made but not as much as I liked due to two circumstances. However, the Version 2 mirror box is done with tailgate in and side bearings attached. Just needs the edges varnishing and the bottom, and corner braces reinstalled. The 3 mirror posts are ready and just awaiting the mirror to go in. There is a strap around somewhere for the sling but I can't remember where.

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Yes, it needs hoovering before the mirror goes in - amazing how much dust drilling 8 holes produces!

Was going to dedicate tomorrow to building the spider but I forgot I had a lunch thing to go to. So probably build that on Monday. Will also start lining up the split blocks on Monday so that I can work out how much of the side bearings need cutting out. This is one heavy mirror box, even without a mirror in! I think I will measure my shed up and see how thick a set of handles I can make to get it in and out.

John

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Today I started on the spider/secondary holder. Reasonably confident the idea will work and dimensions seem a lot better this time, so will crack on with it tomorrow and get that done hopefully. The glue is drying overnight.

That will then leave the pole split blocks to install and line the focuser up, then varnish the bottom edges and I think it'll be time for a test so I can order the ali poles. My aim is to be ready to test for the weekend if it is clear. At least the moon will be bright enough to find easily!!

John

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