Hill's Space

Diy

Posts:

8" Mirror Polishing, Part 3: First Strokes

After all that setup, actually polishing a mirror is surprisingly simple. First you put your mirror on your tool and apply pressure so the pitch flows and takes the shape of your mirror (which happens faster if it’s hot, so you can leave the pitch lap in hot water to heat it up and speed up pressing). Then you take your mirror, put it on your tool, and push it back and forth without applying any downwards pressure. Read More

8" Mirror Polishing, Part 3: First Strokes

Unable to find image IMG_20240127_141903995_1_1.jpg Unable to find image IMG_20240127_153114171_HDR_1.jpg After all that setup, actually polishing a mirror is surprisingly simple. First you put your mirror on your tool and apply pressure so the pitch flows and takes the shape of your mirror (which happens faster if it’s hot, so you can leave the pitch lap in hot water to heat it up and speed up pressing). Then you take your mirror, put it on your tool, and push it back and forth without applying any downwards pressure. Read More

8" Mirror Polishing, Part 2: Curveball Pitch

I’m making a tool called a pitch lap to grind an 8" mirror. Previously, I discovered the best way to find dental stone is a dentist, and made a yellow plaster disk. Pitch lap step 2: Pour the pitch! Pitch is a weird material. It’s a liquid so viscous it looks like a solid. At high temperature it’ll pour like honey, at low temperature it’ll act solid but very very slowly flow. Read More

8" Mirror Polishing, Part 2: Curveball Pitch

Unable to find image IMG_20231216_141319656_HDR_1.jpg Unable to find image image.png Unable to find image image.png Unable to find image image.png I’m making a tool called a pitch lap to grind an 8" mirror. Previously, I discovered the best way to find dental stone is a dentist, and made a yellow plaster disk. Pitch lap step 2: Pour the pitch! Pitch is a weird material. It’s a liquid so viscous it looks like a solid. Read More

8" Mirror Polishing, Part 1: The Power of Teeth

Previously, @Beasmeeply generously donated me an 8" mirror blank, kick-starting an attempt to finish grinding it and make an 8" telescope. There are four stages of mirror grinding, so to figure out which step I needed to start with, I put the mirror into a Foucault mirror tester, and it gave a smooth-ish image, telling me BeasMeeply had gotten through the first two stages of mirror making, rough and fine grinding, and it was ready to polish. Read More

8" Mirror Polishing, Part 1: The Power of Teeth

Unable to find image IMG_20231202_150448568_HDR_1.jpg Unable to find image IMG_20231207_160216875_1.jpg Unable to find image IMG_20231207_162328078_1.jpg Unable to find image IMG_20231207_170016712_1.jpg Previously, @Beasmeeply generously donated me an 8" mirror blank, kick-starting an attempt to finish grinding it and make an 8" telescope. There are four stages of mirror grinding, so to figure out which step I needed to start with, I put the mirror into a Foucault mirror tester, and it gave a smooth-ish image, telling me BeasMeeply had gotten through the first two stages of mirror making, rough and fine grinding, and it was ready to polish. Read More

The Jan 2024 Telescope Shenanigan List

I have many projects in mind for telescope upgrades. Since the last list I’ve completed one and added one. Here’s what I want to do this year telescope wise: #1: Sliced Pifinder (complete!) Complete! I built a Pifinder for 1/5 of the list price by using a different cheaper camera, secondhand older pi and battery pack, and printing and soldering parts myself. It’s been very helpful when it works, and let me take pictures of M33 even without seeing it! Read More

Cracked a Black Hole

Poured some cement into my CNCed mold! Very fitting that my experimental telescope making technique involves a black hole I noticed my mold had warped before putting cement on it - maybe from the polyurethane spray I used, or from waiting a month in between cncing and pouring? I put some weights on it because of the warping, walked away… And the next day I found my wood split down the middle of a boundary between planks. Read More

Pifinder: complete!

I’m building the Sliced PiFinder, a device to help my telescope find things! Previously, I tried using a cheaper IMU but gave up and bought a $30 fancy chip. Originally I didn’t want to buy a $50 GPS USB stick but the PiFinder creator found a $10 solderable GPS unit for a v2, so I bought one and soldered it in. After soldering in the GPS chip, dubiously electrical taping it in place, dropping it and cracking my 3D printed parts, printing new parts, using a soldering iron to remove heat inserts out of the old parts so I can place them into the new parts, printing the case, discovering the case wasn’t designed for my battery and blocks access to the on/off switch and USB ports, melting holes in case with soldering iron, putting on a cover plate over the screen and LEDs… I finally put it on my telescope! Read More

Pifinder Perils

I’m building a PiFinder! It uses a camera to take pictures of the sky, connected to a raspberry pi which uses a database of stars to tell you where in the sky your telescope is pointing. But a PiFinder is $550 new. A stock pifinder uses the newest and most expensive options for pis and cameras, and when I looked at the parts list, I thought: I can build something similar for a fifth of the price! Read More