RLWP

How will you know when you have finished, Damian? I'm not familiar with the tests you are using

Richard

I have lots of fingers crossed for you

Makes this IPad a bit tricky to use, mind

Richard

Is that a New Horizons image of the dark side of Pluto?

Richard

It sounds like biting the bullet and letting John help you has freed up your head to get on with the rest of the scope. First light is nearer now than it was!

Good stuff, Damian - I'm looking forward to sawdust covered posts

Richard

Well, I think it's worth 15 quid and I'll even collect for free!

It seems that Fullerscopes supplied Barbell weights as standard. My MkIII mount was supplied with 1 x 5kg flavoured one.

Hmm, I have one 5kg and two 10kg.

Richard

I wouldn't bother with that old tat. Look, I'll take it off yer hands for a tenner, as a favour, like

A MK VI mount!! You lucky....

I notice the weights on your scope are also from a barbell. I was wondering if mine were original, looks like they are

Richard

Ah!, the Henry V.  Shakespeare quote. Should do the trick  .

Well, I'm sure we are all hoping for the moment that Damian can say:

And gentlemen in England now a-bed shall think themselves accursed they were not here

Sounds about right for a successful first-light test of a hand made mirror

Richard

Imitate the action of the tiger, stiffen the sinews, summon up the blood,

Richard

This is an exciting development

Richard

I'm quite pleased with the RAF motto, it seems to fit your situation very nicely 

Nil Desperandum*

Richard

*Nil Carborundum Illegitimis seems somehow appropriate too

Damian, you aren't going backwards. You've had a bit of practice around the use of fine grits, polishing and mirror measurement. Now you are completing the basic shape and finishing the journey much better prepared than when you started out

Per Ardua ad Astra

I think you will be surprised how quickly it goes, most of my foul-up rectifications do anyway

Richard

What's wrong with the motors then?

Richard

Bung them in the car, that way he can advise on the mirror and your tools and techniques as well. After all, it isn't the mirror you need advice on, it's the making of the mirror

Richard

Will you be taking your laps as well as the mirror?

Richard

This tracker here might help: http://www.isstracker.com/

The circle round the ISS icon represents the horizon of visibility. So in theory, ignoring the observers local limitations, anyone on the ground within that circle should have ISS above their horizon.

I just had a look at tonight's late evening pass with SkySafari and it tells me that when ISS is about 15 deg above my west horizon its' just under 1200km distant yet at 5 deg elevation it's 1800km distant! Which puts it way off over the Atlantic.

Thank you for that - I was expecting to have to do some hard sums

Richard

As it recedes everything is in reverse. Until eventually it's almost stationary as it fades on your easterly horizon. 

As it happens, I stuck my head outside just in time to see the ISS last night. As it disappeared towards the horizon, I thought...

How far away is that then? 

It disappeared at an elevation of around 15 degrees (into the trees). How far away is it: in line of sight to the ISS and; what part of the world would it be over at that point?

Richard

You've gone from a Trebor mint to a polo mint! Keep banging in there buddy remember slowly slowly catchy monkey!

I guess he started with an Extra Strong mint

Richard

My wife thought I was a Hobbit, she's most amused to learn I'm actually a sub dwarf

I didn't know dwarves had a navy

Richard

Anyway back to the mirror making

Damian

A suggestion only!

If you are going to build a variable speed motorized table have a look at the way an old Myford lathe or a large pillar drill press works. Just use pulleys and a slow 4 pole motor ( 1500 rpm). Easy to change speeds and reliable. Just over size the motor and any bearings used if possible. MDF can always be glued and screwed together to increase thickness to anything wanted. But it is not the best product for use near water regardless of what protection used.

Derek

A further DIY tip - you can cut wooden discs either by hand or with a router to make pulleys. They won't be turning quickly for that kind of application, you can make quite a few from a bit of plank in several diameters

I can do cheapskate when required...

Richard

Out of interest it looks like dental paster is dental stone in the UK and easy to get. I think another goes by the name of hydrastone but I can't find it.

John

-

Hydrostone is a modelling plaster: http://plaster.com/HYDROSTONE.html

Richard

Damian,

I don't have anything practical to add, I would like to count myself as one of your admirers for your tenacity and willingness to share what you are doing. Thank you, it's very inspirational

I think I might have a go, perhaps on a 1" diameter mirror - or is that too big a project?

Richard