Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Restoration Question

This topic has been archived. This means that you cannot reply to this topic.
29 replies to this topic

#1 Mr Magoo

Mr Magoo

    Mercury-Atlas

  • *****
  • topic starter
  • Posts: 2713
  • Joined: 05 Nov 2005

Posted 12 May 2007 - 02:03 PM

I have a few restoration questions to ask you old equipment Guru's.
1. When stripping and repainting and aluminum OTA, do you use a special self-etching primer?
2. When repainting the outside of the tube, is there a particular brand of paint that works best?
3. How about paint for the inside of the OTA? I have used Krylon Ultra Flat Black on my dob project, but it stinks and takes a long time to "gas out".
4. When working on the objective, or even EP's for that matter, how do you remove the male threaded retainer rings?
5. How do you keep dust from getting on the objective lenses when reassembling them? I guess I could seal off my bathroom since it is all tiled, install a negative air machine, and don a Tyvek suit with respirator, but that would only serve to reinforce my wifes opinion that I'm losing my mind. :crazyeyes:

#2 mikey cee

mikey cee

    Cosmos

  • *****
  • Posts: 9589
  • Joined: 18 Jan 2007

Posted 12 May 2007 - 02:17 PM

Ken.....on aluminum use zinc chromate primer. I've always used Krylon enamel with an acrylic clear coat. It dries fast and propels onto the surface better than cheap paint from Wal-mart etc. Flat black is best but leave it outside with a cheese cloth or a gauze like item draped over the ends(dust, bugs etc.) It should "gas out" rather quickly. :smirk:Mike

#3 mikey cee

mikey cee

    Cosmos

  • *****
  • Posts: 9589
  • Joined: 18 Jan 2007

Posted 12 May 2007 - 02:23 PM

Ken....on the retainer rings they use spanner wrenches. They are like a pair of slotted screw driver bits that adjust in and out on a bar or rod. The bits then are placed in the two slots of the retaining ring. You can use a plain screwdriver and small hammer and lightly tap the ring loose...but be careful you don't slip and nick the lens edge. :grin: Mike

#4 Preston Smith

Preston Smith

    The Travel Scope Guy

  • *****
  • Posts: 6059
  • Joined: 24 Apr 2005

Posted 12 May 2007 - 03:34 PM

Great Thread!

I'm new at this too so I'll be watching the answers to your questions.

Here's one more:

What are the steps to take if you want to have your equipment powder coated? :question:

#5 Awesomelenny

Awesomelenny

    Skylab

  • *****
  • Posts: 4194
  • Joined: 02 May 2004

Posted 12 May 2007 - 03:40 PM

Hi Ken,

Welcome to the wonderful world of telescope restoration!

I concur with Mikey Cee's approaches with painting. I may add that if you want to achieve the realistic satin black finish on some telescope parts like the old Sears, Tasco's, Unitron's to name a few, Rust Oleum's Satin Black is also a very good and durable paint. On some of the Vintage items like the old A.Jaegers lens cells or such as the Unitron counterweights, the black wrinkle paints are also very good. The idea of putting the item painted with several coats of the wrinkle finish and placing in an oven at 180 degrees Fahrenheit for 30 minutes does an absolutely beautiful job wrinkling the paint evenly. Also, baking in the oven ANYTHING that is painted on metal cures that items drying process very quickly. Just make sure you don't go below or above the 160-180 degree range for about 30 minutes.

Above all, exercise patience and have fun!

#6 Eric P

Eric P

    Viking 1

  • *****
  • Posts: 565
  • Joined: 04 Apr 2005

Posted 12 May 2007 - 04:39 PM

As far as products out of a spray can I've had luck with TopFlite's lustrekote primer and enamel on aluminum. Very durable coating, but the color choice is rather limited.

#7 EJN

EJN

    Skylab

  • *****
  • Posts: 4382
  • Joined: 01 Nov 2005

Posted 12 May 2007 - 05:52 PM

As far as products out of a spray can I've had luck with TopFlite's lustrekote primer and enamel on aluminum. Very durable coating...


And it's fuel proof!

#8 oldsalt

oldsalt

    Astro Philosopher

  • *****
  • Posts: 8812
  • Joined: 12 Feb 2005

Posted 12 May 2007 - 06:22 PM

Unless the finish is chipped, don't do anthing to it but clean it proprly. When cleaning, use a good quality automotive detergent. Once clean, a good quality wax does wonders.If you do need to refinish the tube, try to match the original paint color as close as possible and use a quality automotive paint.Acrylic enamels are tough and durable, if the tube is to large to bake in an oven, use heat lamps to help the curing process. Paint the outside of the tube first, then the inside. When using tape to mask parts use the blue painters tape as it does not leave a sticky residue and remove it within 24 hours.

#9 Bonco

Bonco

    Skylab

  • *****
  • Posts: 4008
  • Joined: 17 Apr 2006

Posted 12 May 2007 - 06:52 PM

I've been considering taking my OTA to Carsmetics and getting an estimate. I would give them only the tube with everything removed. Me thinks they might do the job at a reasonable price and they have a professional paint shop. This isn't as fun as doing it yourself but for a treasured collectable this might be a good option. If I do it I'll post the results.
Bonco

#10 oldsalt

oldsalt

    Astro Philosopher

  • *****
  • Posts: 8812
  • Joined: 12 Feb 2005

Posted 12 May 2007 - 06:57 PM

If you can find someone who repaints aircraft, you'll really get a nice job. you have to be wary of paint thickness around mating surfaces.

#11 Mr Magoo

Mr Magoo

    Mercury-Atlas

  • *****
  • topic starter
  • Posts: 2713
  • Joined: 05 Nov 2005

Posted 13 May 2007 - 09:32 AM

Great info from everyone. Thank you. Where would you find this adjustable spanner wrench Mike? I've restored a fair amount of old sheet metal working tools and equipment, but none of them were aluminum so I wasn't sure about the paint on it.

#12 Mr Magoo

Mr Magoo

    Mercury-Atlas

  • *****
  • topic starter
  • Posts: 2713
  • Joined: 05 Nov 2005

Posted 13 May 2007 - 10:25 AM

I did a little more digging and found several ajustable spanners like this one: Lens Wrench I searched the web with "lens wrench" and found several different types. Some were not adjustable. There were several on the big E auction site, but most shipped from far off lands that may be not very cost effective with the overseas shipping.

#13 ngc6475

ngc6475

    Fearless Spectator

  • *****
  • Posts: 5026
  • Joined: 02 Mar 2002

Posted 13 May 2007 - 10:49 AM

There was a thread on the subject of repainting refractors some time ago, and it can be found here.

#14 twhite

twhite

    Vanguard

  • *****
  • Posts: 2462
  • Joined: 28 Jan 2006

Posted 13 May 2007 - 02:02 PM

I have two of the SKGrimes adjustable spanners -- the flat time and the pointed type. They are excellent quality, and I highly recommend them.

Tony

#15 clintwhitman

clintwhitman

    Caveman

  • *****
  • Posts: 5842
  • Joined: 01 Jan 2007

Posted 13 May 2007 - 09:31 PM

A quicky "Rust Oleum's Satin Black is also a very good and durable paint" Lenny is right on, there paints rock for mounts and they make a white gloss that comes in a large can professinal grade I think that is a very good paint for tubes. Let them sit for a week and rub them out with TR3 cleaning wax and The tubes look like you sent them to a shop. The satin black I do the same thing, also if you nick the black you can just spot touch up and rub it out again and you cant see the repair!!!! As for the rings about 90% of the time I just use a little screw driver and unscrew it.. I know I know..... What would you expect from a CAVEMAN

#16 clintwhitman

clintwhitman

    Caveman

  • *****
  • Posts: 5842
  • Joined: 01 Jan 2007

Posted 13 May 2007 - 09:38 PM

OOO lint on the edges of your 9mm WHAT R U DRUNK lint on the edges make viewing boring globs and faint galaxies much more interesting, Like little aliens crawling around the universe at least that’s what I tell the kids looking thru my scope!!!!

#17 clintwhitman

clintwhitman

    Caveman

  • *****
  • Posts: 5842
  • Joined: 01 Jan 2007

Posted 14 May 2007 - 07:09 PM

Lenny showed me the screw driver trick except he jambed it into the lens while tring to turn the ring

#18 oldsalt

oldsalt

    Astro Philosopher

  • *****
  • Posts: 8812
  • Joined: 12 Feb 2005

Posted 14 May 2007 - 07:35 PM

Sring loaded clip-ring pliers can be found at Sears and automotive parts stores. They will do the job on eps just check how much travel you'll need before you purchase.

#19 Jae

Jae

    Apollo

  • *****
  • Posts: 1083
  • Joined: 13 Apr 2006

Posted 14 May 2007 - 07:38 PM

Great tip on the spanner wrench. I couldn't find any bigger than 3" but I needed one for a 4" f15.

thanks !!

#20 2manyscopes

2manyscopes

    Mariner 2

  • *****
  • Posts: 266
  • Joined: 16 Sep 2006

Posted 14 May 2007 - 08:57 PM

What are the steps to take if you want to have your equipment powder coated? :question:


First step would be to contact your powder coater of choice to see what stock colors are available. There are thousands of colors available but very few shops keep a large inventory. In my area any color not in stock runs about $120 for 5lbs. plus a $120 fee for a special run in that color. I did a 6" f/15 refractor plus mount and all the associated bits and bobs for $132 using four separate stock colors.

The best powder coater in my area does not do any surface prep so I found a media blasting firm to do the big pieces in a process called soda blasting and I did all the small stuff with aluminum oxide 220. If you have any holes that need filled you must use a product like AllMetal and let it cure for two weeks otherwise the powder coat will not stick.

If any of your parts are cast aluminum make sure you you bake them in your oven at 400 degrees for 1 hour. In all likelihood you will see a brown residue on the cast parts after this. If so, clean it off and bake it again. Repeat until they come out clean. The powder coating process will bake your parts at 400 degrees and if any residue migrates out (outgassing) the powder coat will fisheye in those areas.

Last, be sure to tell the powder coater which holes to plug. They will fill the holes with rubber plugs or mask off areas not to be caoted with a special tape.

For all of my parts I cleaned them with a no residue brake cleaner then a no residue electronics cleaner before dropping them off. I believe the coater dipped them in some kind of solvent as well.
Bill

#21 2manyscopes

2manyscopes

    Mariner 2

  • *****
  • Posts: 266
  • Joined: 16 Sep 2006

Posted 14 May 2007 - 09:08 PM

1. When stripping and repainting and aluminum OTA, do you use a special self-etching primer?

5. How do you keep dust from getting on the objective lenses when reassembling them? I guess I could seal off my bathroom since it is all tiled, install a negative air machine, and don a Tyvek suit with respirator, but that would only serve to reinforce my wifes opinion that I'm losing my mind. :crazyeyes:


When spray painting aluminum with a rattle can I usually skip the primer and wash the parts first in hot soapy water then in pure distilled white vinegar. I rinse well and paint as soon as the parts are dry. I also bake them in an oven as others have mentioned.

As far as keeping dust off of optics during reassembly it's simple....I just take them to a clean room at work and use plenty of dry nitrogen to blow them clean. At home I use plenty of canned air...no shaking or tipping of the can allowed and try to work quickly. It's not easy but it can be done.

I don't see a down side to your wife thinking you are crazy! :crazyeyes:
Bill

#22 clintwhitman

clintwhitman

    Caveman

  • *****
  • Posts: 5842
  • Joined: 01 Jan 2007

Posted 15 May 2007 - 08:43 AM

How do yoy bake a 4" unitron in a oven. Go to your local pizza joint and beg?

#23 Glassthrower

Glassthrower

    Vendor - Galactic Stone & Ironworks

  • *****
  • Vendors
  • Posts: 18465
  • Joined: 07 Apr 2005

Posted 15 May 2007 - 11:07 AM

:lol:

#24 2manyscopes

2manyscopes

    Mariner 2

  • *****
  • Posts: 266
  • Joined: 16 Sep 2006

Posted 15 May 2007 - 11:15 AM

How do yoy bake a 4" unitron in a oven. Go to your local pizza joint and beg?


If you are talking about baking it to cure a rattle can paint job you could use heat lamps instead. If you are talking about baking in preparation for powder coating I doubt that the tube will be cast and thus needs no baking. To be honest a good powder coater will bake out all the parts for you just so that he doesn't have to field questions about why the coating fish-eyed but not all powder coaters are created equal.

I started asking about powder coaters at local machine shops. I talked to 7 machinists and every single one without hesitation suggested the same company. There are 7 others in my town but not one even rated a mention! I'm very happy with the job they did.
Bill

#25 Mr Magoo

Mr Magoo

    Mercury-Atlas

  • *****
  • topic starter
  • Posts: 2713
  • Joined: 05 Nov 2005

Posted 15 May 2007 - 01:08 PM

I could just see my wifes reaction to finding scope parts in the oven. :slap: Doesn't baking the paint make an awful smell? I sure wouldn't want the next roast coming out tasting like baked on enamel.


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics