A help in Flocking your 200P

[stevetynant]

Just finished Flocking my 200p - used the CloudyNights Guide for the most part but thought a write up would be handy for anyone in SGL whos thinking of doing this - theres a lot of us 200'pers about so might be a good resource for all of us. Whether its worth the effort I'm not sure yet as like all of us the clouds and awful British Summer are precluding any stargazing at the moment but my scope has now gone from this

to this

believe me - the flash in the photos does not do justice to the difference when looking into the tube- hopefully this will translate well to better contrast when eventually I return to observing in the Autumn.

Where to start - well firstly a disclaimer - please ignore the huge piles of clothes in the background - this is my daughter returning from Uni who thinks everything will magically get washed and put away while she stays in bed until three in the afternoon - I wish I was that age again. Also as its gone 11pm I may have to do this in a few edits - and most importantly - this is the way I did it - its not the only way and I'd appreciate comments for anyone else who's tried this and found better or easier routes - hopefully it can be a resource for those who follow.

Flocking a 200p

Firstly get your tools together - this is pretty much what you'll need - perhaps the only things you might not have will be a permanent marker (about £1 from Tesco) and some narrow hobby knife blades which I got for about £2 from a local market but I'm sure Amazon will have some equally cheap equivalents.

The second thing to remember is you need to strip down the scope - this might at first seem a little scary but if you take your time and do it in this order you will be fine- I'd never done it before and stripping it down and reassembling was easy - just take your time and be methodical.

the first thing to do is take off the Primary Mirror. If you do this first then nothing that subsequently drops off the scope will damage it.

I had already attached some Bobs Knobs to the bottom of my scope - for this reason I put the scope upright but on a pillow so the bolts did not have to take the strain - as it transpired this was unnecessary but you can't be too careful I guess. Stand the OTA upright with some support either side to make sure it doesn't fall over as you remove the primary. All you need to do is remove the six screws at the bottom of the scope.

Before you do this though - mark one of the screw holes on the OTA with a pencil - lift the OTA - and mark on the Primary (obviously not the mirror itself). When you come to reassemble the OTA and Primary - line up these marks again - this will make collimation a lot easier

The OTA and Primary came away suprizingly easily. You may have to "jiggle" the scope slightly but it is no more than that - make sure the tube is lifted away from the Primary without touching it and put it to one side. Put the primary away safely so you don't trip over it before it needs to be reattached

I took this opportunity to brush off any dust that had accumulated on the primary - I did this by getting a piece of kitchen roll and lightlly brushing across the mirror and blowing - not rubbing it it any way

Put it safely out of the way

The next thing to do is to remove the ring at the top of the OTA but before you do this use a small pencil to mark a circle just inside this ring all around the circumference of the OTA itself = we'll use this line later as the upper most limit of where the Flocking material should be attached.

Take the Collar off by removing the six screws around the collar of the OTA above the Secondary.This ring is used to keep the OTA cylindrical - you will see what a good job it does when you come to reattach it later on. The screws to be removed are the smaller ones NOT the large silver ones which are actually holding the secondary in place.

The upper ring now removed its time to take off the secondary mirror. WITH ONE HAND HOLD THE CENTRAL ASSEMBLY OF THE MIRROR SO IT DOES NOT FALL - with the other hand unscrew the silver screws on the outside of the OTA one by one until the secondary is free and again put it safely away.

I used this opportunity to darken the outside and back of the secondary with a Black PermanEnt marker making sure NOT TO TOUCH THE FACE OF THE SECONDARY MIRROR Take your time and don't rush this and you'll be fine - the secondary has now gone from this

to this

Back to the OTA - Next to take off is the focussing assembly - I still have the original on my scope and taking it off is easy - 4 screws, one on each corner (you can see 2 in the image below)held on to the scope by four small bolts on the inside of the OTA - again they came apart fairly easily - put to one side again

Again I used this as an opportunity to remove any reflective surfaces by using the permanent marker to colour the Outer Focussing Tube as shown below

Before

After

Next to take off was the Spotting scope Base - again easy tow screws but underneath is a plate which will fall off when the bolts and screws are removed (this is what happened to me anyway - good thing the primary had gone at this stage)

Outside

Inside

Put away safely again

Lastly to be taken off are the two assemblies that mount the tension handles on the Dob - again just two screws on each to be removed - there are bolt heads and washers on the inside of the OTA that need to be removed and put aside

[stevetynant]

and thats it - the hardest part done - OTA completely stripped down

So thats the hardest part done - Easy - unfortunately the most frustrating part is still to come - attaching the Flocking paper.

I got the Flocking paper from FLO - If you do the same you will need 3 rolls

First thing to do is measure the circumference of the OTA - the way I did this was by wrapping the Flocking Paper around the outside of the tube then allowing a few cms overlay - it attaches to itself quite readily to the flocked side of the paper so give your self a little room for error

Then just cut to size and while your at it - cut the other two exactly the same size (the OTA's not going to change shape any time soon)

Right now the frustrating bit starts - I've seen in a few guides where people have pegged the Flocking paper to the tube and tried to take a little off at a time like this (remember this is a student bedroom - ignore the dirty clothes mountain)

well I just could not get on with this at all and I tried several times - the easiest way I found was to lay the OTA horizontally on the floor- use the seam within the OTA to get the paper on straight and just take a little of the backing paper off at a time smoothing it down as best as you can to stop as many air bubbles as possible. I started from the top of the OTA - remember the pencil line we drew earlier

don't let the Flocking paper get higher than this at the top of the OTA - the reason is that the ring that we removed earlier is quite a tight fit - if the flocking paper goes above this line you may not get the ring reattached easily or worse case at all.

Once you've wrestled with the paper and got it on the top half of the OTA - do the same at the bottom - again leaving a gap of about 5mm at the top of the scope which will allow the screws holding the Primary to be reattached

Once you have the top and bottom of the tube flocked you will end up with a tube with a gap in the middle- something like this

So now all you have to do is cut a piece about 8 Inches wide to cover the gap (overlaying on both ends so none of the OTA is visible)

That is the hard part out of the way

Now stand the tube upright and methodically from the top use a narrow modelling blade to cut out all the holes that require screws or insertions making sure that any stray bits of flocking paper are removed from the outside.

Now shine a torch down the OTA and find any air bubbles that you've missed and with the same narrow blade puncture the bubbles and smooth out all the air you can.

Whilst the Focus mechanism was out I again took the opportunity to flock the inside of the draw tube- whether this makes any difference I'm not sure but it was an easy mod and only took 5 minutes so why not - only flock to the upper collar of the draw tube not the whole way - should then look something like this

Cut the flocking paper to size and you end up with this

Now start reassembling the tube in the opposite order you took it apart so the Primary mirror is now the very last thing you reattach.

At every stage during the reassembly process I again used the permanent marker to darken any screws or reflective surfaces so all the bolt heads every time you attach something blacken them out - again not sure how much difference it will make but it can't hurt either.

Take your time putting it back together as you did disassembling it and that's pretty much it your scope has gone from this

To this

The photos don't really do justice to how dark this scope now looks inside - for a lot of this project I was using one of the headlights we use when out and about observing (white not red this time) - so hope this helps and best of luck and don't forget to re- colimate your scope.

This is far from the only way to do it but its worked for me - Good luck and Clear skies.

Steve

[Oily]

I did mine t'other day and was wondering wether or not to do the draw tube?

[stevetynant]

Well its easy enough to do Oily but I think if you have finished it and put your scope back together I wouldn't bother- if you haven't well why not it doesn't take 5 minutes. If you do it though only flock up to the collar - thats the outer side of the tube not the bit that sits in the OTA - If you go over this line you may catch it when you put the adaptors in

[David Smith]

Nice write up Steve.

[nightfisher]

Thats a job very well done, and a great step by step set of instructions to any one planning to do this, i did my Tal100rs and im still waiting to see the difference, i also flocked the draw tube on the tal as this seemed a bit bright inside

[Gina]

Yes, very nice detailed write-up Should be a big help to everyone with the same scope or indeed any Newt.

[midjam]

Very useful detailed instructions, have bookmarked this for future reference.

[fredster]

That's a brilliant post and very helpful as its something i have considered for ages but not done.

[Oily]

Well its easy enough to do Oily but I think if you have finished it and put your scope back together I wouldn't bother- if you haven't well why not it doesn't take 5 minutes. If you do it though only flock up to the collar - thats the outer side of the tube not the bit that sits in the OTA - If you go over this line you may catch it when you put the adaptors in

It's all back together now Steve but won't take me 10mins to take it off,flock and re-fit,thanks for the 'how to' I thought about doing one when I flocked mine but my IPhone camera isn't great at taking hi res shots

[Damo636]

Great guide Steve, excellent step by step instructions.

[icrusoe]

Is it just the pictures, or is that flock paper similar in texture to sandpaper?

[stevetynant]

must be the pictures icrusoe - texture is quite velvety in fact

[astrofox]

Many thanks for the detailed description. I dont have the Dob but a 150PDS. However at all seems so similar.

[Nibor]

A very clear and helpful guide to flocking - it takes away a lot of the "fear factor" - I am hoping to aquire a reflector shortly so I will be referring to your guide should flocking be required.

[texaspete1973]

Thats a pretty good how to there Steve

[stevetynant]

Cheers Pete wasn't too bad just set some time aside and be methodical I would say

[Phil-lost!]

Great guide, just what i was looking for.

[NoSiriusly]

I've just finished following this guide. It was brilliant. I forgot to allow 5-10mm at the primary end which resulted in wrestling the back apart before cutting the flocking back.

All is well now though and I agree with the OP's comments. Those photos just don't do it justice. Sooooooo dark in there now. The whole exercise took me a few hours as I was super careful. I also took the opportunity to paint the focus tube and secondary.

I was surprised just how dusty my primary was!!!

Thanks for your help

[Charic]

A good read and easy project to follow, yet no-one has mentioned if there was a real difference in over two Years, don't keep us waiting?

Its something I have considered, but I try to alleviate stray light sources first, hiding in the shadows, or from within the  tent?

I think there's  a difference from within my tent, but  my eyes are  just better dark adapted, more than anything else, but with  the scope is still sticking out of the tent, maybe a little flocking may help, but then so does my DIY dew extender!

Also to note, does flocking material fibre fall onto the mirror, and is it easy to keep the flock clean?

Its still something to consider for the future.