78 Repair

An excellent, detailed article concerning 78 record playback exists elsewhere. Highly suggested reading!

Un-warping

Place the record between two sheets of plate glass (or any completely flat surface of moderate weight.) DO NOT place any additional weight, add heat, place them in the sun, etc. Putting additional weight on the record will cause the peaks between the grooves to flatten out somewhat, causing distortion during playback, and heat can cause the shellac to soften considerably, causing all kinds of problems. I'm of the "less is more" school on dewarping; unless a record is unplayable, I don't worry about it.

Cracks

Spreading and Playback: Prevent incipient cracks from spreading by fusing the edge of the recording where the crack starts with a match. Scotch taping the edge with several tight layers also helps. Others have used "Captain Tolley's Creeping Crack Cure, a marine sealant. Lots of surface noise will result if you get the stuff in the grooves. It comes with instructions and is available from Sea-Band Int'l. Cost is about $7. Yet others use Superglue.

Repairing:
Some have said it can not be done, but you can repair a cracked 78, allowing it to play again without the painful click every rotation (or at least minimizing the click so it is no longer as much of a distraction). I have used this method to successfully repair 78 s with small cracks as well as cracks that extend from the rim to the label. (Successful repair means that once done, you can play the record and not know it has a crack.) This repair also stabilizes the crack.
I have used the following method to successfully repair old shellac 78 s for play on old phonographic machines which use steel needles. Use caution if you try to play the repaired ones on a machine that uses another type of stylus, since you could damage the stylus unless the repair is done extremely well.
This method is useful for the repair of linear type cracks which are clean. Rim chip repair is not as successful, and repair of cracks where there has been a lot of loss of material along the crack line are also not as successful, although repair still improves greatly the quality of playback.
Materials needed:

Epoxy ( I have used Duro Master Mend, others may work as well)
Toothpicks
Old or new steel needles
Steps:
Part one: Repairing the crack

Working on a hard flat surface, press the record down on both sides of the crack, and apply electrical tape to the rim where the crack is. Electrical tape sticks much better than regular scotch-type tape. This step aligns the cracked edges and stabilizes it in that position. This step is vital. If you can not get the edges aligned level with one another, the repair will be unsuccessful, as you will still hear the click.
Mix a very small amount of Epoxy
Spread thin line of epoxy along crack with toothpick
Let this sit for just a minute or so. (this allows it to seep into the crack) Before the epoxy starts to become gooey use the beveled edge of a new toothpick to smooth out the thin line of epoxy laid down in step 2. Wipe off the tip of the toothpick as needed as you perform this step. Do not worry about this epoxy getting on the record surface to either side of the crack, as once the epoxy has hardened it peels off the surface, but remains in the crack.
Once the epoxy on the first side has set up (10 minutes or so) repeat steps 1-3 on the other side. (If it is a small crack at an edge, you can do both sides right away, as you can hang the wet edge off your surface.) 6) Let record sit until epoxy has fully hardened.
Part two: Getting the excess epoxy off the record

At this point I put a new needle on my exhibition sound box, and play the record through the cracked area. This loosens the epoxy on the records surface. ( One could also use a #2 sound box, but I would not recommend performing this step with an orthophonic sound box, although once the crack is repaired the record should be playable using an ortophonic sound box.).
Using the sharp point of a new toothpick you now free up the rest of the epoxy from the surface of the record. If some resists coming off, you can play the record again over the crack to loosen it some more, or use an old steel needle to peel the epoxy out of the grooves.
Run tip of the toothpick along the crack to free the loose epoxy.

If you aligned the edges properly to begin with, you will now have a record with a stabilized crack which should be playable with much less distraction.
Even though the amount of epoxy remaining in the crack is very small, it forms a very strong bond between the broken edges. On one record I repaired I had not been careful enough in aligning the edges, and so I wanted to rebreak it and do it over. However, I could not get the record to rebreak in the same spot, and ended up creating another crack. So you had better get it right the first time. But if the record is cracked and minimally playable to begin with there is really not a lot to lose in trying.
Good Luck
Steve Kaufman
questions or comments welcome

Chips / Needle-drops

China graph pencils work well. At least the needle won't pop as loud (or jump). Some residue will be dragged into later grooves, so use just enough to achieve the desired results. When selling the record, be sure to note the repair. Repairs of this nature are difficult to spot for some collectors, especially on worn surfaces.

Once the needle tracks normally though this, a digital recording can be made and the click or pop removed using an audio editing program like Audacity. Zoom in on the pop and delete it. You'll find that the the actual pop only lasts a very small fraction of a second and can be deleted without detection nearly all of the time. Nobody will be any the wiser.

Cleaning

Records - Schellac: Fill a large bowl with barely warm water and add a mild dish detergent such as Ivory and a little vinegar. Leave the faucet running slowly. Wet a wash or micro-fiber cloth with the solution then apply to the playing surface of the record. Very gently wipe the surface with the cloth, taking care to wipe in the direction of the grooves. Do not let the label get wet! Let the solution run along the grooves in an effort to loosen dirt, grime, and wash away any iron filings. Rinse the record under the slowing-running warm water tap, then gently pad the record dry with a dry towel. Let the record stand overnight to dry completely because mold spots or worse will occur if they are placed in folders still damp. As for the label, again, avoid applying the solution or water to the label! Some labels hold up better than others when wet, actually turning different colors and bubbling right away, but why risk it?! If the label is dirty then gently blot the label with a damp cloth that has a water-vinegar mix to kill the mold. Avoid rubbing the label. As a side note, some people say that using distilled water to rinse leaves less moisture and debris. David Breneman adds that Photo-Flo can be used instead of water in all steps. PF is intended to prevent water spots from forming on film as it dries and is not intended to be a cleaner, however its detergent-like properties for breaking down the surface tension of water do make it effective as a mild cleaner in some cases and may help the record dry safer without rinsing as rinsing may leave behind whatever contaminants the water may contain.
A few NEVERs:

Never play your 78s wet!
Never use water on Edison Diamond Discs, Acetates, Hit-of-the-Week, or any other 78 records that are not made of shellac.
Many record cleaning solutions intended for LPs contain alcohol and will destroy schellac 78s.
Never soak records or let labels get wet.

Records - Edison Diamond Discs: As the record jacket suggests, do not use water, but an alcohol solution. Edison diamond discs (thick) were made out of Condensite (pretty much the same as Bakelite) on a core of varying material

Records - Acetates (Home Recordings, Recordio, etc.): The Audio Archive offers an excellent, extensive article that covers the cleaning and playing home recordings. They should not be cleaned in the same way as other records as their surface material differs greatly.
NEDCC offers detailed instructions with excellent results.

Labels: Keep the label dry! Never wet a label unless it is so soiled that other methods won't remove the dirt. Many labels will "bubble" if dampened, particularly Victor, Emerson, Paramount, and other glossy types. For picky collectors, this can degrade the record's value. Try cleaning dusty labels with a dry sable brush. Dirtier labels can be cleaned by buffing gently with a soft towel or piece of corduroy. A kneaded artists eraser (available at any art supply store) is also a safe way to remove dirt or stains without dampening. If you must use water, apply it very sparingly with a slightly moistened towel and dry immediately.

Don't want to try these methods yourself? Try The Disc Doctor for expert cleaning supplies.

Records - Schellac:	Fill a large bowl with barely warm water and add a mild dish detergent such as Ivory and a little vinegar. Leave the faucet running slowly. Wet a wash or micro-fiber cloth with the solution then apply to the playing surface of the record. Very gently wipe the surface with the cloth, taking care to wipe in the direction of the grooves. Do not let the label get wet! Let the solution run along the grooves in an effort to loosen dirt, grime, and wash away any iron filings. Rinse the record under the slowing-running warm water tap, then gently pad the record dry with a dry towel. Let the record stand overnight to dry completely because mold spots or worse will occur if they are placed in folders still damp. As for the label, again, avoid applying the solution or water to the label! Some labels hold up better than others when wet, actually turning different colors and bubbling right away, but why risk it?! If the label is dirty then gently blot the label with a damp cloth that has a water-vinegar mix to kill the mold. Avoid rubbing the label. As a side note, some people say that using distilled water to rinse leaves less moisture and debris. David Breneman adds that Photo-Flo can be used instead of water in all steps. PF is intended to prevent water spots from forming on film as it dries and is not intended to be a cleaner, however its detergent-like properties for breaking down the surface tension of water do make it effective as a mild cleaner in some cases and may help the record dry safer without rinsing as rinsing may leave behind whatever contaminants the water may contain. A few NEVERs: Never play your 78s wet! Never use water on Edison Diamond Discs, Acetates, Hit-of-the-Week, or any other 78 records that are not made of shellac. Many record cleaning solutions intended for LPs contain alcohol and will destroy schellac 78s. Never soak records or let labels get wet.
Records - Edison Diamond Discs:	As the record jacket suggests, do not use water, but an alcohol solution. Edison diamond discs (thick) were made out of Condensite (pretty much the same as Bakelite) on a core of varying material
Records - Acetates (Home Recordings, Recordio, etc.):	The Audio Archive offers an excellent, extensive article that covers the cleaning and playing home recordings. They should not be cleaned in the same way as other records as their surface material differs greatly. NEDCC offers detailed instructions with excellent results.
Labels:	Keep the label dry! Never wet a label unless it is so soiled that other methods won't remove the dirt. Many labels will "bubble" if dampened, particularly Victor, Emerson, Paramount, and other glossy types. For picky collectors, this can degrade the record's value. Try cleaning dusty labels with a dry sable brush. Dirtier labels can be cleaned by buffing gently with a soft towel or piece of corduroy. A kneaded artists eraser (available at any art supply store) is also a safe way to remove dirt or stains without dampening. If you must use water, apply it very sparingly with a slightly moistened towel and dry immediately.
Don't want to try these methods yourself? Try The Disc Doctor for expert cleaning supplies.

Removing stickers

"Goo Gone" a very benign, citric based solvent used to disolve glues. Be sure to test it first on another record sporting a label of the same manufacturer and vintage. It softens pressure sensitive stickers on paper labels so you won't tear or lift the label up. Takes patience waiting for it to work.

Playback Tips:

General
Even with a new needle and a properly rebuilt, compliant reproducer, a certain amount of damage is unavoidable. I always discourage people from playing truly rare records on vintage equipment; we owe it to posterity to be good custodians of these treasures! Take it from someone who knows what it means to trash a $1,000 record. Make sure your tonearm is properly weighted and tracking is easy. As the record jacket says, "Permanent needles do permanent damage!" Change your needles every time if you have steel, bamboo, tungs-tone, etc. needles. Even diamond needles need replacing more often than people think (and saphire much more often.) Different manufactures during different time-periods used different sized grooves - use the one that fits. Speaking of which, truncated eliptical styli play the mostly-undisturbed sound recorded on a higher spot on the groove wall, which is where the sound was recorded on a mono, lateral record. They also tend not to skate on the bottom of the groove where no sound (except hiss) resides. The opposite is, of course, true for vertical-cut records.
Disc Slips:
Try double-stick tape, the kind with an adhesive on both sides. Look for one that is re-useable in hopes that it sticks well but can be easily removed without damaging the record. Try Scotch Removable Poster tape or even DAP "Fun-Tak Reusable Adhesive," which is a putty-like substance, easy to remove, but sticks well enough for the purpose of flattening out a flexible phono record. Need a more rigid surface to stick the record to? Consider sticking it to a rigid record, although there are drawbacks to this as you might imagine.
Cracked:
Playback of cracked records can be aided by slightly elevating the part of the crack the needle travels over first with a piece of paper placed along the rim of the record. Move the paper(s) along the edge until an optimal sound is achieved.

Many thanks to: David Breneman, Hal Byrnes, Adrian Hindle-Briscall, David R. Hoehl, Steve Kaufman, Jeff Lichtman, Kurt R. Nauck, III, David Owens, Carl Ratner, Doug Rhodes, Joe Salerno, John E. Smith, Paul J. Stamler, Allan Sutton.

Future of restoration