ecormier

I checked out the play sand at the local building supply store, and was not impressed by its cleanliness. I see many here recommending sawdust. The next time I do some wood cutting outside, I'm going to try laying down a tarp to catch the sawdust. I might also try asking a local cabinet maker.

As for the Stuart Semple Black 3.0, it's a whopping $300 a litre, and I've read several negative reviews about it being greyish and not durable. I'm hesitant to spend that kind of money on it.

14 hours ago, Peter Drew said:

I've used a similar technique using sand, sawdust or fine aluminium filings.  Breaking up a black surface is really effective, specially on the inside of baffle tubes in small Maksutovs/SCT's which tend to be very reflective.      🙂

Do you remember the mix ratio you used with sand?

18 hours ago, Mr H in Yorkshire said:

I have used this technique in a home build scope. Looking obliquely along the painted surface, it is actually quite good. I used sawdust - any particles escaping are less dangerous to glass. I applied the paint then threw in the sawdust and rolled it around. Once dried applied more paint.

I have to do all my wood cutting outside, so I unfortunately don't have a means to collect the sawdust in a clean manner.

Hi Everyone. I'm working on a mirror box for a 20" dob. I've painted the interior with Rosco Super Saturated Velour Black paint (vinyl acrylic), which is popular with A/V enthusiasts for painting home theaters. However, I must say that I'm disappointed in the paint's apparent lack of blackness. I've recently stumbled upon this article by Gerd Neumann Jr, which recommends mixing sand with chalkboard paint. As I understand it, the sand provides a rough texture to the finish which helps to avoid reflecting light.

I've paid a lot for my Rosco Velour Black paint, and would like to try mixing sand with it before I abandon it for a different kind of paint. Has anyone here tried mixing Rosco paint with sand? Any tips?

The Gerd Neumann Jr article suggests a 1:1 volumetric ratio for mixing as a starting point. I'd like to hear what mixing ratios worked well for you.

I found a home improvement article that recommends mixing play sand to create a non-slip painted floor surface, so that's the stuff I plan to use in attempting this.

I will test on a piece of scrap wood of course, but hearing what worked well for others would be great.

I'm not comfortable discussing someone's personal affairs here. While I hope things are all right with her, I mainly wanted to retrieve her collimation guide. Mods, please lock this thread.

My original post should have started as "What happened to AstroBaby's website". It's none of my business what happened to her.

I don't mean to intrude on anyone's personal life. I got the information I needed.

Thanks everyone. I generated and saved a PDF from the Wayback Machine link AngryDonkey has kindly provided. The formatting is a bit off, but all the information and pictures seem to be there. I hope everything is okay with AstroBaby.

What happened to AstroBaby and her website? She had the most wonderful guide on collimation with a cheshire. That's where I would usually send beginners not equipped with a laser collimator.

I would ask her myself via PM, but she hasn't been active here for a long while.

I'm trying to find a snapshot of her collimation guide on the Internet Wayback Machine, but it's being very slow right now.

Is this a non-rotating focuser? Does adjusting the focus rotate the guide camera?