Flocking, any advice before I start.

[martindale]

Hi,

I have a 12" Newt that I intend to flock the inside.

I have bought a 4mtr length of self adhesive flocking 45cm wide, if I cut this into 3 equal lengths these will be longer than the length of the tube.

3 lengths will be more than enough to cover the internal circumference.

But the thought of trying to stick these large pieces to a concave surface without bubbles or creases is quite daunting.

Has anyone any experience, tips or advice before I start.

Cheers,

Paul.

[ncjunk]

When i did the c11 i cut it into strips rather than try to do it in one piece.

Its easier to put a strip on or readjust to if you need to.

I cant remember what width i cut them to.

[martindale]

Just now, ncjunk said:

When i did the c11 i cut it into strips rather than try to do it in one piece.

Its easier to put a strip on or readjust to if you need to.

I cant remember what width i cut them to.

Did you overlap the strips or butt them up together

[ncjunk]

4 minutes ago, martindale said:

Did you overlap the strips or butt them up together

A bit of both. In a few places i overlapped but it isn't really obvious and wont affect anything in terms of light path.

As i dont spend time looking down the scope its not a problem.

[vlaiv]

I did flocking of a 130/900 OTA I used to own.

It does seem daunting but in the end it was not so bad. I also did multiple strips. Couple of things that I might suggest - You will need some help, no question about it, as it is a long OTA think of the way to get a strip through without too much sticking to sides. This could be done either by having OTA vertically placed and then lowering the strip or by means of some long pole or something to help you guide the strip. Once you have strip inside, each person should take their side and put a tension on strip so it is flat as possible - then proceed with layering it first on one side and work your way down trying to squeeze the air out, also use something to smooth the surface - like when washing something with the sponge - you might have to use something on a stick so you can reach all the way down.

My OTA had much more curvature due to smaller diameter but I manage to do it. I did about an 1cm overlap on sections - it was pretty flat so no issues with that. If you end up with a air bubble - either squeeze it out or use a needle and put a small hole in flocking material and just press it down. At the end use scalpel / utility knife to trim the excess flocking material and punch out any holes in ota (like focuser, screw holes and such).

I would not worry if there are small wrinkles and such inside - It is only cosmetic thing, flocking material should be pretty durable, with good adhesive and waterproof so it'll stay in place. As long as no wrinkles intrude in light path (and they should be really big to do so) you are ok, unless you have real need for it to be "perfect". Of course if at some point flocking material starts to peel off - then you would need to strip it and do the process again - it did not happen to me and I used that ota both in cold and warm weather even in dewing conditions.

Hope this helps

[martindale]

1 minute ago, ncjunk said:

 

8 minutes ago, martindale said:

Did you overlap the strips or butt them up together

A bit of both. In a few places i overlapped but it isn't really obvious and wont affect anything in terms of light path.

As i dont spend time looking down the scope its not a problem.

 

Cheers Neil, overlapping does sound a lot easier

[ncjunk]

To apply i lifted one end of the backing paper by 20cm and attached the flocking removing the air bubbles. I then slowly pulled off the backing paper whilst rolling the flocking.

 

[Uranium235]

Also, when before you apply it, roll it up leaving your first edge free - then pop a bulldog clip or clothes peg on the rest of the roll so it doesnt spring open inside the OTA... once the first edge is applied, take the clip off to let a bit more out, put the clip back... and so on and so forth.

Also if your tube has an internal (raised) seam, dont try to flock that - just leave it. Dont worry too much about the odd one or two air bubbles or creases they wont affect it in any way - ive never got it 100% right. To be honest, when I did my 200pds I only flocked half of it (from the front, to about halfway down) as that is the most sensitive area when it comes to stray light entering the telescope. Additionally, I flocked my dew shield so there is at least 1.5ft of flocking before the focuser.

Oh, if you get any bit of fluff on it while doing it - the best way to remove that is with a bit of sellotape (like you would when removing bobbles or hair from your jumper).

But the best part is..... the smell of a freshly flocked telescope ...... mmmmmmm flocked..

[DRT]

Here is a link to a thread I posted on Flocking a Skywatcher Flextube 300P

It contains some pictures of how I did it and also some links to other threads that you might find useful.

 

[brantuk]

Using an ironing board sprayer/moisturiser, I could spray a little water onto the inside of the tube before sticking each piece in. Then if I made a mistake or it didn't butt up correctly, I could move it a little easier to make corrections. Once it's all done though you need to leave it at least 24hrs in a warm room to dry out before a final smooth down to ensure it's all sticking nicely.

Any loose edges can be fixed down with a small tube of carpet glue spray. And give it a good hoover or sticky tape clean up so black fluff doesn't come off and fall on the mirror.

[DRT]

4 minutes ago, brantuk said:

give it a good hoover or sticky tape clean up so black fluff doesn't come off and fall on the mirror.

Very important!!

I use these to take all the excess fluff off before sticking the flock to the OTA.

[martindale]

Thanks all,

I'll try and remember to post before and after photos when I get round to doing the flocking.

 

[D33P]

On 16/07/2016 at 12:34, ncjunk said:

To apply i lifted one end of the backing paper by 20cm and attached the flocking removing the air bubbles. I then slowly pulled off the backing paper whilst rolling the flocking.

 

I did this, flocked ota in one piece. Left flocking slightly bigger than needed and run a knife along where the seam would be. Once butted together and brushed to remove loose fibres, you can't even see the join.

Admittedly this was a small tube (C5), but I can't see it being any more difficult for a larger tube.