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New Lightbridge Rocker box.


Brantuk

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Ok - so my dob rocker box isn't really that cream crackered, but it is a bit heavy to move around, and the base board around the center pin is beginning to wear making a bit of a sloppy AZ joint. Over time this will absorb moisture and just get worse - and I've already over tightened the AZ knob to the extent it's pulled the bottom nut half way up through the baseboard.

 

So I decided to build something stronger, and lighter. It's eventually going to be sealed, and either varnished or painted, till it's weather proof - we'll see. I was going to source some very nice expensive Baltic Birch 18mm furniture grade ply for the job - but decided to do a prototype first in B&Q 18mm (3/4") ply board in order to: a. hone my woodwork skills, and b. have a great excuse when I botch it up lol.

 

Anyway - I had a photo shoot in the garage this morning, so stay tuned for a few "starting" pics and comments.....

 

 

 

 

 

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First step - appraisal of tools:

Well one delapidated Workbench left over from my first marriage, a jig saw and a masonry drill with a wood setting.

IMG_5267r.jpg

Went down to B&Q for the wood and got a couple more tools for doing straight lines and circles (for alt/az bearings). That means a disk saw and a router:

 

 

IMG_5269r.jpg

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Looking at the workbench it ain't that big and there's a huge gap in it - soooo... I lopped the edge off this piece of 1" Contiboard waste I had lying around and attached it to the underside. This will clamp nicely onto the Workbench giving me a bit more real estate for the size of work I'll be handling:

 

IMG_5272r.jpg

IMG_5273r.jpg

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Now you may well notice a circular shape on the top - that's me practising making Alt bearings - and ruining the top surface. So I'm very glad I didn't do it on top of the Workbench! Do bear in mind cutting perfect circles is new to me - so I'm just filling in for anyone who, like me, doesn't have a lot of wood working skills.

Looking at youtube vids and build threads on other forums, I discovered I need a circle jig or the router. So I duly removed the router baseplate and cut a bit of 9mm ply in a sort of jig shape - drilled and countersunk 4 holes - and screwed it to the base. Fun or wot!

 

 

IMG_5274r.jpg

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So there's a nail close to the the router 4" from the outer edge of the bit to give a nice 8" dia alt bearing. This is just a test to build my confidence cos at this point I've no idea what I'm doing. There's also a hole 27.5cm from the bit to make a cirular az bearing under the base board of 55cm diameter. And after a load of clamps, buzzes, and dust, these are the shapes I ended up with - including a spoiled worktop.

IMG_5275r.jpg

IMG_5276r.jpg

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Finally - proof of concept - I am just stunned how accurate the arch is to the Lightbridge Alt bearing diameter - there's only 1mm or 2mm in it which will accommodate the bearing material easily. Now I'm brimming with over confidence about making bearings - pride comes before..... etc....

 

That's all for today folks - if you're still awake after my droning on. Tomorrow I start on the actual wood and might even saw a leg off if you're still tuning in lol :)

 

IMG_5277r2.jpg

IMG_5278r.jpg

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Great stuff Kim. :thumbsup:

 

Keep it coming with any mistakes as well. I'm going to learn a bit from this. Need to get myself a router and practice with it.

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Thats a good starting point Kim.

Look forward to this project taking shape. :thumbsup:

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Thanks chaps - until recently all I ever had was an electric drill and a range of hand saws and other assorted manual tools. Even the jig saw is a relatively new thing for me.  I'm hoping to harvest parts from the original rocker box, but will post up anything extra that I need to get - and of course any goofs (plus hopefully solutions).

 

One credit I must mention is Damian (mapstar) over on SGL who very kindly sold me some spare Formica left over from his superb dob build. That stuff is otherwise minimum order megabucks - an 8'x4' sheet is around £90. Here's his thread if you want a real treat: https://stargazerslounge.com/topic/266267-the-mapstar-22-build/#comment-2915131

 

:)

 

 

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Nice collection of tools Kim and a great start for your new base. 

 

Keep the updates coming.

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Very instructive, interesting and... entertaining too Kim. ?

Impressive tool that router!

I have got an old workbench, but I I ain't got one of them!

 

looking forward to more diy... :)

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Your Black and Decker Workmate looks new, it needs more abuse. :lol:

Fantastic thread mate and I'll be watching with interest. 

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I agree with Martyn, give it to Mick for a weekend he will have it on fire in no time.

 

:P

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9 minutes ago, Daz Type-R said:

I agree with Martyn, give it to Mick for a weekend he will have it on fire in no time.

 

:P

 

:dontknow: :lol:

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16 hours ago, Brantuk said:

Thanks chaps - until recently all I ever had was an electric drill and a range of hand saws and other assorted manual tools. Even the jig saw is a relatively new thing for me.  I'm hoping to harvest parts from the original rocker box, but will post up anything extra that I need to get - and of course any goofs (plus hopefully solutions).

 

One credit I must mention is Damian (mapstar) over on SGL who very kindly sold me some spare Formica left over from his superb dob build. That stuff is otherwise minimum order megabucks - an 8'x4' sheet is around £90. Here's his thread if you want a real treat: https://stargazerslounge.com/topic/266267-the-mapstar-22-build/#comment-2915131

 

:)

 

 

 

That SGL post IS an amazing link! Inspirational stuff!

Thanks for that Kim ?

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It's an awesome build indeed Stephen - and the end product is just such a thing of beauty! I was sooo.... impressed. :)

 

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Well the drugs have got me well zapped today so there's not a lot cooking on the "work done" front - maybe I'll come round and do a bit more this evening. So why am I here now - well the Formica arrived this morning all nicely cut and rolled up in a tube courtesy of mapstar (thanks Damian). And lovely it looks too - here's a pic set against what will be the rocker box base board:

 

 

IMG_5282r.jpg

The black disk is a counterweight I got from astroboot a while ago - being used to flatten out the formica with 2 others. I suddenly realised I actually have all the bearing materials now - so here they are:

 

IMG_5279r.jpg

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To the right you can see a pack of B&Q slide glides - that idea came from DazType-R's AZ setting circle mod (thanks for that Daz). They glide very nicely over the surface of the Formica and come ready chamffer'ed with a metal center disk and screw hole - so they only need to be stuck down in position and screwed on firmly. The real test will come under weight of the ota - adjusting the center pin to achieve the required "sticktion":

 

IMG_5283r.jpg

And finally the Alt bearing material - you'll never guess what it is - yup that's right velcro. Now If I tell you where I got this tip from I'd have to kill you - shameful skullduggery was employed so ask me in person and I'll whisper in your ear. It's the loopy side of the velcro - not the hooky side. But It seems to work a dream on Alt bearings - here's a sample on my test bearing made yesterday:

 

IMG_5284r.jpg

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The next job will be routing out the Alt bearings and shaping the sides - so I need a clear head and steady hand when I do that (so I don't loose any limbs). Some would say press on lol - but nope - that's it for today's photo shoot folks. Thanks for watching. :)

Edited by Brantuk
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All looking good Kim.

 

I was amazed at how good the felt bearings are on the LB. You wouldn't think it would be but it is.

 

What router bits do you have to shape the sides or make it look pretty.

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Thanks Mick - yes I looked all over for the "load bearing felt" use on the alt bearings and couldn't find a sausage.

Apparently it's used in all sorts of industrial applications - but you try getting small quantities of it for a reasonable price..... no chance!

 

At the moment I'm using the router bit that came with the machine. I also got a couple of spares - just ordinary ones though nothing fancy.

Now you've got me thinking...... lol.

(Just don't expect a work of art like Rusty Johns dob :) )

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Next installment.....

Well I've done a fair bit more today so to start with here's the wood:

 

The square piece under the work bench is 55cm square and will be routed into a 55cm dia circle to form the base board on which the rocker box will stand - it will have feet - possibly adjustable I haven't yet decided. And the slide guides will be screwed on top of it, and on which the formica glued under the box will ride.

 

The oblong standing upright next to it is going to be the two sides forming the Alt bearings. It's 55cm wide by 41" tall because I'm one of those confused baby boomer kids who were dragged by the feet screaming into the age of decimalisation and never did like it. But don't get me going on politics or my next project will have to be a soap box from which you'll never get me down lol.

 

Anyway - the sides will be 20.5" high with the Alt bearings at 16.5" from the base board making the whole thing 1.5" lower and, crucially, the eyepieces easier to reach when pointing at the zenith.

 

IMG_5285r.jpg

On top of the bench are the base of the rocker box at 55cm x 55cm square, the front piece 51.4cm wide x 11" high, and the rear piece 51.4cm x 2.5" high. There's no rear piece on the original box so this will add a little strength. A curve will be cut into the top of the front piece to accommodate the curvature of the ota when horizontal.

IMG_5286r.jpg

Edited by Brantuk
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