How to Fix a Cassette Tape.




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*this instructable takes for granted that you can use basic hand tools and have good dexterity with small parts. the only items required are the tapes, a small screwdriver set, a pair of needle nose pliers is helpful, and scotch tape.*

for all those folks still holding on to a cherished but broken cassette tape, here's how to properly fix the common ailments. in this instructable we'll cover transplanting the tape from a busted shell to a good shell, how to get into a welded shell cassette, how to splice a tape, and how to fix squeals.

the lowly cassette.. if you were a kid of the 80's you knew them well. littered around the car's glovebox, piled around a boombox, or crammed in your pocket on your way to school, cassettes were everywhere. it's how an entire generation swapped music or impressed their partner with their ability to create a mix tape.

thanks to the ipod and its huge storage abilities, the mixtape has become a lost art. swapping music went from being a very social activity to something as mundane as checking email. despite the advances in tech, millions of cassettes still survive as do the machines to play them on.

granted the music on many tapes is available in digital form but not all. lots of folks used hidden recorders to make bootleg tapes at concerts. just look at the huge online community that still swaps grateful dead recordings. many of those bootleg recordings were initially made on cassette. there's also mixtapes that were made with a personal touch that a playlist on an ipod can never come near.

enough reminiscing, let's dig in!


Step 1: What Kind of Shell Do You Have?

cassette shells basically come in two types, welded together and screwed together. the screwed together shells will have from 1 to 5 screws holding them together. the welded ones have no screws. both halves are joined using a process called sonic welding which makes repair a little difficult but not impossible.

welded shell tapes must be cracked open. screwed together tapes come apart easily once the screws are removed.

Step 2: What Repairs Require Getting Into the Tape?

before touching any magnetic tape, wash your hands with dish soap and dry them thoroughly. you dont want to get grease, grime, oil, or dirt on the tape itself.

if your tape has snapped and wound itself up so you have no tape in the access hole, you need to open the case to fix it. if your tape is mangled or broken but both ends are still hanging out of the shell, you can fix that without opening the shell. mangled tape can be straightened out and carefully wound back up by turning the hubs on the cassette. broken tape in which both ends are hanging out of the shell still can be spliced without opening the shell. see the step on splicing tape.

cassettes which are squeaky, binding, wrapped on themselves, or the shell in just in very poor shape, will require disassembly. some DIY articles mention using vegetable oil to cure squeaky tapes and that is 100% wrong. do not do that as it will gum up the works on your tape machine and ruin the tape over time.

Step 3: Getting Into a Screwed Shell Tape

on a screwed together shell, you remove the screws and the shell comes apart. best bet is to perform the whole operation without lifting the tape off the table so you don't spill its guts all over the floor. you should be able to remove the top half of the shell while leaving the bottom half and its contents laying on the table.

make sure you use a NON-magnetized screwdriver for this. magnetized tools will cause drops outs in your tape. remember this is magnetic media. do not use magnetized tools for any of this work.

screwed shell tapes make great donor shells. if you have any screwed together cassettes that don't interest you, don't toss them. they are perfect for transplanting the guts from a welded shell cassette that had to be cracked open for repair.

Step 4: Getting Into a Welded Shell Tape

if you are going to be repairing a welded shell cassette, you will need a donor shell to move all the guts into. even when they snap open in a clean fashion, welded shell cassettes never go back together properly no matter how much crazy glue you have. old cassettes are cheap at flea markets. get some screwed together donor shells if you plan on fixing old tapes.

it's destroy stuff in a vise time! (who doesn't like destroy stuff in a vise time?)

there's two well known ways to get into a welded shell tape. one is to use an exacto or other knife to pry your way around the seam, snapping the welds as you go. i have tried this and impaled myself too many times.

my preferred method is the vise. insert cassette into vise as pictured and squeeze till you hear the seams pop. turn the tape 90deg and repeat. this should cause enough breakage for you to be able to carefully pull the tape apart without spilling its contents all over the floor.

this doesn't always work as planned. the tape in the picture turned out to be made of a very brittle plastic and it just exploded its guts all over the floor. yep, safety glasses are a good idea here.

just about all pre-recorded tapes will be in a welded shell.


Step 5: You Dropped the Tape and Made a Mess..

no biggie.

take the fullest spool and get it back into what remains of the shell that is useable as pictured. place finger on edge to keep it from unwinding further and slowly wind the tape back up. slow, tedious, and hard to do at first but once you get the hang of it, it becomes easy.

Step 6: Components of a Casette Tape

to explain what's inside a cassette, we'll use the one that came apart peacefully.
pic 1 - inside a cassette with half its shell removed.
pic 2- the slip sheet. this reduces friction between the tape and the shell. these can be clear.
pic 3 - the pressure pad. this provides even contact between the tape and the heads on the machine that read the tape. this is an important part and without it, most cassette players will have poor audio reproduction. there are some high end machines that don't require the pressure pad but about 90% of machines made need it.
pic 4 - the Mu metal shield. it has nothing to do with cows. it's a magnetic shield required by older tape machines.
pic 5 - the rollers. most cassettes have two of these. really cheap cassettes may have just a plastic peg here. these can squeal. the only fix is a miniscule amount of nylon safe lubricant on the metal shaft of the roller. we are talking a very small amount as you don't want any lube getting on the tape.
pic 6 - the tape "pancake".

Step 7: A Word About Slip Sheets

those little plastic sheets are important. they lower friction between the tape and the sides of the case. they also help keep the tape evenly wound. on very old or cheap cassettes, the slip sheets can be made of inferior material that wears out easily causing tape squeal. replacing old and worn slip sheets cures some squealing issues on cassettes.

in the pic there are two slip sheets from the same cassette. the shiny side faces the shell, the dull side is coated with a dry lubricant and it faces the tape pancake. sometimes these can be easily interchanged from one shell to another. worst case scenario being that you may need to do a little trimming so they fit.

in pic 2 there's a closeup of a little plastic peg the slip sheet has to fit around. notice there's a V cut in the slip sheet. when swapping sheets from one tape to another, keep in mind you may have to do a little trimming to make it work.

some tapes used a clear slip sheet. those make it harder to keep track of which side is up so try to keep them laying in the shell in proper orientation. if you do drop it, there's still hope for figuring out which side is up. note in the 1st pic the dull slip sheet has its indentations facing up. that's the side that's supposed to go against the tape.

Step 8: Tape Popped Off Hub - How to Fix

a common failure on very old tapes is that it will pop off the hub on fast wind. see pic 1. this is an easy fix. on the ends of the tape you will usually have a leader. the leader is a non magnetic bit of tape and it's what's attached to the hubs. the leader attaches to the hubs using a snap in plastic clincher.

the clincher can be opened by sliding it off the hub. see pic 2 and 3. remove the bit of leader left on it. take the leader from the tape pancake, snip off a small piece so you have fresh plastic to work with. lay the leader in and insert the clincher in end first facing the rest of the leader. see pic 4. pinch shut with needle nose pliers. it should click in.

if all went well, it should look like pic 5.

Step 9: Snapped Tape - How to Fix

snapped tape can happen. often times its caused by a poorly functioning machine that ate the tape. a machine that eats tape is malfunctioning. it's likely to be extremely dirty inside or the belts are failing. two thing outside the scope of this instructable but not impossible to fix.

do not keep putting tapes into a machine that eats them!


a snapped tape can be fixed but keep in mind that you will lose that little bit of music that got mangled.

pull out enough tape from each spool so you can work. 6" is generally enough to work and not have it blow around from your breath. yeah, cassette tape is that light. it's very important that you keep proper orientation of the tape here. you will be applying the splice to the backside of the tape and you need to make sure you do not inadvertently flip the tape. easiest way i have found to do this is use a post it to hold tape in place while working. see pic 2.

snip the ends of the snap tape so you have nice square cuts. lay the post-it down on the table sticky side up. lay one end of the tape down. the side of the tape that touches the play heads (faces outside of the tape) should be what is stuck to the post-it. use tweezers or needle nose pliers to lay the other end of the tape down making sure its lined up, facing the right way, and has a very minimal overlap.

use a piece of trimmed invisible scotch tape to hold splice together. see pic 3. scotch tape should NOT overhang anywhere on the magnetic tape. any overhang will mean that there's adhesive tape waiting to catch on the mechanism and bind things up. see pic 4 and 5.

once done, carefully pull tape up off post-it sheet. pull one half up first, then pull up second half. trying to yank it all at once may ruin splice.

this same process can be used to re-attach a leader to a tape. on very old cassettes, the factory splice that attaches the leader to the magnetic tape can fail. this is common in really old sony tapes from the 70's.

is scotch tape the right stuff?
nope, it is not. in reality you are supposed to use splicing tape. splicing tape was at one time a common item at radioshack and music stores. it is no longer easy to find. it can be ordered from tape specialty places but for the average Joe just wanting to listen to an old tape, the expense far exceeds the attention span. quality scotch magic tape, the kind that disappears when stuck down on something will suffice.

Step 10: Reassemble

once done with your repairs, put the contents back in. don't forget the slip sheets, metal shield (if tape had one, not all do), pressure pad, and rollers. while reassembling, make sure tape is properly threaded in the case. its easy to munch the tape up while trying to fit the case halves together. see pic 1.

Step 11: Enjoy Your Tape!

you did it!
you just took part in a forgotten art, that of repairing a cassette tape. now try doing it 1980's high school style on the glove box door of a moving camaro while trying to make it back from lunch before your buddy finds out your deck ate his tape! ;-)

**some additional links and info**

if you're truly interested in tape machines, check out

it's a site for audio hobbyist with a love for all things tape related. they are friendly folks that will gladly jump in give you a hand with any tape questions you may have.

if you're interested in learning more about cassette tapes and all the different types there are, check out my Cassette Tape 1101 instructable..

for those of you that are playing or recording regularly on cassettes, i wrote an instructable on how to properly clean the tape path and what the names of all the parts are. it can be viewed here..

into old tech? follow me on instagram as vintagetechguy to see random pics of interesting old tech.

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30 Discussions

There is one very important problem that wasn't covered in your instructions: if the tape (unplayed for years) doesn't play, fast-forward or go backward one. What can be done? Doesn't work on high-end Pioneer and Nakamichi players? The player hums for a few seconds on any of these 3 functions and then stop, or on another machine, it plays for a second then stops, and after removing the cassette, I notice that 1-2 inches of tape came out of the cassette. There appears to be resistance from the plastic cassette tape. Should I put a drop of oil on each of the cassette wheel as well as the player's transport system??? RSVP for you or anybody that had that problem and got it fixed. Now, my 300-cassette vintage collection doesn't play. Thank you.

3 replies

Reply 1 year ago

Sorry for the ancient reply but just noticed this question. Hopefully others can benefit from the answer.

Take the cassette, hold it by the edge with thumb and pointer finger of same hand, slap cassette body against other hand with quick flicks of the wrist. this help settle uneven layering caused by fast winding which causes drag. Ultimately if it keeps binding you may have to move the tape reels themselves into another shell. It's possible the slipsheets are gumming up.

never ever ever use oil

Looks like a problem with your tape deck: the takeup reel doesn't turn. The capstan and pinch roller work (the tape wouldn't play otherwise), but a belt or roller probably failed because of age. As for stopping, many decks have a rotation sensor coupled with the takeup reel; when playing or rewinding, the machine will stop shortly after no pulses from the sensor are detected (which usually means that the tape has reached the end).

It's a good idea to give your decks some love: look for a service manual, then open the enclosure, check and thoroughly clean the mechanism, using compressed air, isopropyl alcohol and some Q-tips. Ethyl alcohol is not as good as it evaporates a lot slower, and can swell the rubber to some extent. Change the belts (determine the correct length with a piece of thread wrapped around where the belt is supposed to be; don't rely on the length of the old belt's remains). Lubricate according to the manual, avoiding excess oil or grease.

The tape deck's parts in contact with the tape (i.e. capstan(s), pinch roller(s) and - most important - heads) must be cleaned with Q-tips and isopropyl alcohol every few tens of hours, depending on the tape quality (higher-end tapes leave less residue, allowing more time before cleaning). Generally, if you hear less and less treble over time, cleaning the playback/universal head is a good idea.

NO OIL on tapes! that would be a bad thing.

there are some tapes that are known to bind up like that but its an uncommon occurrence seen only on really old 1960's-early 70's tapes and some really cheap tapes.

you wont want to hear this but chances are it's your decks if all your tapes are doing the same thing. the issue may have to do with the belts. most cassette decks are reaching the point where the factory belts are stretched or melting into a blob of tar. it's a fairly common problem that's well documented and not a terribly hard fix. it's easy to get dirty though cleaning up the melted belt goo.

you can get new belts tailored to your machines from marrscommunications on the web. they even bring instructions. to get an idea what you're looking at as far as belt goo and cleanup, see my instructable on reviving a vintage norelco cassette recorder.

if you need help, has a very knowledgeable and friendly user base that will gladly field questions. whatever you do, dont toss your gear. plenty of us in tapeland are used to rebelting decks and even buy "broken" ones.


4 years ago on Introduction

Great Instructable. One quick question though. On most of my old tapes, the pressure pads have either popped off or become oddly misshapened. Are replacements easy to get, and what would be a good way of re-affixing them? Any help you good give me would be greatly appreciated.

Keep up the good work!

1 reply

1 year ago

Yo you don't have to take a VICE to the cassette if you want to get inside of it. Use a flathead screwdriver to slowly crack it along the seam around the entire tape. It'll split clean in half. It works I swear!

I do like your reassembly instructions though its allll looove

3 replies

Reply 11 months ago

be careful using a screwdriver. a great many end up being magnetized either on purpose or by accident and can lead to drop outs in the audio on the tape. make sure whatever you use has no magnetism.


Reply 1 year ago

True, it can be done like that. The downside to prying the thing open with a screwdriver xacto knife, butter knife, etc is you will stab your hand. Been there, done that. Since the welded case won't be reused, the vise method is a sure way to not stab yourself trying to get the shell apart.


Reply 1 year ago

I meant to say I do indeed reuse the split shell. I always cleanly scotch the original welded plastic back together. Maybe I'm too nostalgic but I prefer to maintain the original tape and also not waste the plastic. Nothing against the rest of your method, it's just that picture of a tape vice'd up made me loco.


2 years ago

Thanks for the info. Sadly I have a mini cassette with a special family moment that my kids pulled apart and I now have several pieces. How can I tell which side of the tape is the front?

2 replies

Reply 2 years ago

this will require some detective work.

you'll need a good magnifying lens. pull about an inch of tape out of the cassette and let it lay flat against edge of cassette almost is if it were in its normal position during playback. tape must not be folded over or flipped.

in good light, closely inspect the cassette with a magnifying lens. you are hoping for visible wear in the tape that you can use to line up the piece that broke off. often times on thin tapes like MC the machine will impart slight stresses on the tape itself that can be found with a magnifying lens. you may also see wear pattern caused by the heads of the machine as they do drag across the tape in normal operation.

micro cassette audio tape has magnetic oxide on one side and bare plastic on the other. its easy to figure out which side is the magnetic oxide layer with a magnifying lens but the problem is this wont tell you which way the tape traveled. you have a 50/50 chance of getting it spliced the right way if you just go by which side has the oxide and matching it to the tape in the cassette. worst case the section you spliced is backwards and you'll have to flip it.


1 year ago

I sooooo Love this site!!! OK, I'm a dinosaur who has been trying to enter the 21st century. Some I Love, but some is too damn frustrating. Trying to play an old CD I made years ago and discovering that the apparatus I'm using says I have the wrong format. then there's 'protected' content, then... well, you get it. iPods are Satans gift to mankind! Everything is becoming so proprietorial and we have lost so much freedom to pass on, receive and copy things, and in this case music. I'm going back to tapes! I once spent hours, devoted entire days to 'segwaying' music of my choice to cassette tapes until I had an impressive collection of just music 'I' liked. Then decided to move to t6he woods, get back to nature and reduce my carbon footprint. Part of that reduction meant no grid electricity, ergo the need for tape recorders diminished.I left hundreds of cassette tapes outside (as I had no room for them in my cabin) Thanks to Instructables help, I built the technology I needed, developed a 12VDC system in my cabin and now I have the means to play cassette tapes. Then retrieving them in the overgrown weeds & bushes, they're not in the best shape. One by one I have been rejuvenating them. These cassettes are 40 years old. But most are working. Some still have problems. I notice a consistent reference to some type of lubrication, which in my case, has been indispensable. I have very sparingly used a combination of lubricants and my fav is a dry lubricant we know as graphite (dust) but even that one must NOT get it on the playable side of the tape, and still use it frugally. Great article, great site, and great people ! I'm a one-man-show out here and sometimes the going is tough. (worth it)but when I want 'REAL' answers, this is where I come. Thanks everyone who contributes!!!!!

BTW, cassettes have released me and given me the freedom I experienced in the 70's to tape/copy ANY music I so choose that I can get my hands on without being at the mercy of the powers-that-be when they decide to change formats or systems or whatever we're locked into and at their mercy. No other tape deck has told me I have the wrong format to play a tape on. I am a bit restricted in finding ways around 'protected' stuff, but where there's a technology, there's a counter-technology! ]


1 year ago

Does anyone know what kind of adhesive is used to splice tape ends? Where my tape came apart is where the brown tape meets the clear tape at the end of the reel. the brown tape has a few centimeters of clear tape that meets the clear tape. The clear tape is at least 20 cm .They overlap and looks like they were glued. I was able to perform surgery and get the tape back in place and glued the ends with super glue. It broke as soon as I tried to play it.

Please help. It's a rare cassette that I can only find bootlegs of. I found one original but they want close to $100 with shipping. yikes.

1 reply

Reply 1 year ago

the proper material is called splicing tape. it is very hard to get nowdays. radioshack USED to carry this stuff. the only modern source may be ebay or National Audio Company. sadly, you may have to resort to something like 3M clear gift wrapping tape. this is not the right stuff but its the only option next to spending $10+ for a roll of splicing tape you only need an inch of.


3 years ago on Introduction

Please can you help me.. I have a 1960 cassette tape with my dads voice on it and the tape looks fine I need to put new case on it..My dad past in 1966 Thank you

1 reply

Reply 2 years ago

Hello Barbara. Did you get your cassette re-shelled? If not, I can do that for you....


2 years ago

What about a tape that was eaten by a cassette player and parts of the tape got wrinkled? Is there anyway to smooth them back out for so that they are playable?


3 years ago

I have an acdc back in black cassette that was sitting in my car for close to 10 years and from what i can see on the spool is that the side of the spool tape looks like it has dirt on it will that effect it at all