Alex's reattach loose wires & repair rips in Mylar

Note: You do not need any 3M super 77 spray glue at all!

The electric current will hold the wires against the Mylar until the milloxane is dry.

Note: Magnepan will not ship milloxane from Mid October until April/May due to freezing during shipment. - You have to wait until spring.

If replacing wire on the speaker:

Buy the following:

From Magnepan: Correct Gauge Wire. (If you are nice to Margaret (she almost always answers the phone), they will put together some wire on a spool for you, even for the older MGI and MGII speakers).

If you are not buying the tweeter kit, you will need to order / ask for the materials individually.

I recommend updating the speaker cloth for $20 each. They come in off white, black, and dark grey. The dark grey looks great.

Also, ask for some of the newer connectors to attach the wires that do not use solder (but also ask for the solder in case you need some elsewhere).

Other Supplies Needed:

If you have any tears / holes in your Mylar, talk to the repair department to see if they can give you any scrap Mylar.

Clean the surface with acetone to remove all previous glue (don't worry about letting it soak (it may take 30 - 60 seconds to soften the glue. (if you are doing the base/midrange wires, make sure you draw a picture of the layout of the wires and/or use the other speaker of the pair as a reference).

Skip this part if you have no tears or holes in your Mylar

If you have any small tears or holes in the Mylar surface, refer to my posting archived here. This following section is a detailed explanation of how to repair larger tears in the Mylar.

Remove/separate the magnet/Mylar (the metal frame that holds the is the central part of the speaker), separate it from the frame. Carefully pull off the metal braces that run across the width of the front side of the speaker (this allows the speaker to curve a little more. You may even want to flex the speaker, or brace or have someone flex the speaker to create a curve in the speaker so the Mylar is loose across the width of the speaker. Trim a piece of strong 3M tape or piece of Mylar if magnepan will supply. Take some Pieces of paper towel or thin plastic, and slide it in the hole - make sure to tuck the edges under the Mylar. Cover the rest of the speaker you don't want sprayed. Spray the 3M super 77 spray glue, wait 1 minute, pull out the paper towel/plastic in the hole, and lay down the piece of Mylar / 3M tape(glue side up - not down). Let dry for at least 1 hour. Trim another piece of tape or Mylar sprayed with 3M super 77 glue( let glue dry a couple of minutes before you lay it down. Lay down and stretch out as much as you can as you lay it down. Use 3M Spray glue or stronger 3M high strength spray glue to re-attach the metal braces (use c - clamps to hold each side of each brace). The re-attaching of the metal braces will flatten out the speaker panel, and stretch out the repaired area. I have done this repair for areas as large as 2" wide and 5" high with very good results.

Order the correct wire and milloxane from magnepan. Also, ask for some of their new connectors they use (instead of solder - it's what they are using now - they are mini claps that sandwich the wire between 2 metal surfaces screwed down together). But also, make sure they send you some silver solder for some of the other joints if they don't you can buy some at electronic stores - buy some flux as well. Don't go cheap on the soldering gun either, it's not worth the hassle. I've used cheap/lower power ones and it takes too long to melt the silver solder).

The less mass you add to the Mylar, the better your frequency response will be. Just think, your speakers will sound better than they did new!

When you get the coil of wire Magnepan sends you, lay the speaker down, - clean your hands (to remove oil etc.)and then lay out exactly how much wire you will need to go up and back between the magnets. Cut the wire to length, leaving about 1 foot of wire at the ends(better too long here than too short). Strip off the coating with a razor blade, or sandpaper.

Tweeters

- Connect an electric current through the wire - 12 volts at 1.75 Amps will do the trick just fine. The electric current will make the wires warm (quite warm after a while, but not near enough to burn through the Mylar. You could probably get away with little more, say 2.5 amps, but that's about it. I used a Radio Shack power supply for about $30, just get the one that is 1.75 amps of power. Connect the ends of the wires, and you are on you way.

Lay the wires down, stretch the wire out some to remove the curves in the wire. At each end, just past the end of the magnets, bend the wire around a pen ( or something slightly smaller diameter for the tweeter - if you have), looping the wires back and forth at the ends of the speaker, just past the ends of the magnets. Make sure the wires are right in between the magnets for best results.

Use a good quality fine paint brush - not the one in the can of milloxane. You need to brush it on sparingly! Brush the milloxane back and forth in the direction of the wires, but be sure to initially go across (side to side)the wires(gently so you don't move the wires out of place), and then in the direction of the wires to spread out the milloxane. The goal is to be sure you get milloxane on both sides of the wires all the way down the length of the wires. You don't need to be too conservative as you initially apply the adhesive, but spread it out up and down the length of the wires before it starts to dry. If you are thorough in your application, you will only need one coat. If you are concerned you didn't coat it good the first time, trim the ends of the wires, solder (or use the newer clips magnepan has), and then test the speakers after a few hours or the next day, turn the volume up quite loud to be sure there is no buzzing sound. If there is, just apply another light coat of the adhesive.

With the electric current warming the area, the glue will set faster ( it will start to dry in about 1 - 2 minutes, but will not be dry for several minutes). Just start at one end and work your way down to the other. Just keep coating the wires and move down the wires a few inches per minute to stay ahead of the dry time, but be thorough in your coating as to not miss any areas of the wires. Don't be as conservative with the milloxane at the ends of the wires as you want it to adhere well. Be sure as you paint the adhesive on, the wires stay between the magnets. If the wire shifts some, use the paint brush (or the other side of the brush) to guide the wires back into place, and continue painting it on. If the ends of the wires don't seem to be tight against the Mylar, just make sure you coat the area , and as it starts to dry, just keep an eye on the ends, and press them down every minute or two, until they stay down.

Keep the Power Supply on the whole time until the milloxane is dry ( give it at least 45 minutes to 1 hour. But longer is fine.

Midrange/Bass areas

- do the same as for tweeters. If 12 volts at 1.75 Amps is not enough to keep the wires in place, you may want to go higher on the amperage, but just pay attention to how much heat the wires are producing. You don't have to be as concerned with a little more milloxane here. A touch more mass won't affect the sound like with the tweeter section. You will need to drill out the rivet(s) that hold the 1" black plastic disk(s) in place (the real old MGI and MGII's don't have these). Be careful not to get metal/plastic shavings falling down between the Mylar and the magnets (this happened to me, and it was really impossible to get them out - it didn't seem to affect the sound though, but just be careful). Pour acetone on these plastic disks as they are glued down very well. Let the acetone soak for a couple of minutes, take pliers, grab the disk and gently attempt to twist/pry them of. Go buy a small nut and bolt and lock washer to replace the rivet you drilled out. Be sure you draw a diagram of the wires as each model speaker has some rows of wires with one wire going up and down the length of the speaker, and other rows have two wires. Each model of speaker is different too. You can use the other speaker as a reference if you are doing one speaker at a time.

After the milloxane has dried and you have re-trimmed the ends of the wires to the correct length, re-strip the ends, and then attach them (either to the newer clamps, or solder them in place, then test the speaker(s) at higher volumes to be sure you used enough milloxane. Listen for any buzzing sound. If you hear buzzing, just apply another thin, but full coating over the entire surface again, wait for it to dry, and that's it.

Put your speaker cloth covers on using the staple gun.


This is a detailed explanation of how to repair larger tears or holes in the Mylar.

(Vertical tears of more than 1 ½ inches, and holes larger than ¾ inch). You can use this to repair smaller Mylar problems as well. You may not need to remove the metal braces to complete the repair (however, it will give you better results).

Other Supplies Needed:

  • Acetone (Home depot - any hardware store.)

  • Good paper towels.

  • Rubber gloves (for removing acetone)

  • Paint Respirator (Don't breath a bunch of the

  • Acetone - it evaporates quick -or just make sure you are in a well ventilated area).

  • Staple gun & staples - buy a powerful one. ½ to ⅜ inches long.

  • Power Supply- Radio Shack 12 Volt 1.75 Amp - About $30.

  • Paint brush(s) - 2 fine ones - don't use the one in the milloxane can - it's not fine enough.

  • C - Clamps - small 4 - 6

If you get any breaks in the wires, or are replacing the tweeters, buy a soldering gun - higher amp version, solder flux, and silver solder

Drill with drill bits (if you have the original MGI or MGII, you won't use this) (used to drill out the rivet used to hold down the mylar to create the mid and base sections of the driver)

Small nuts and bolts with lock washer (used to replace the small rivet(s) you will be drilling out)

Carefully pull away wires from affected area. Pour acetone on the affected area, and let soak for a few seconds first. ( 1 inch surrounding the hole)

Call Magnepan and order milloxane adhesive/UV protector. Ask them for a small piece of Mylar to repair your problem (you may have to be nice to Margaret here (or talk to someone in the back)

Note: they will not ship it in the winter - it cannot be frozen). If the area affected is your tweeter area, order a tweeter repair kit (about $40), and remove the tweeter and replace wires after repairing hole.

Trim off loose Mylar with a razor blade make the hole rectangular or round, but remove loose or jagged edges of Mylar.

Clean the area to be repaired with acetone to remove old adhesive. Before cleaning with acetone, protect the magnet surfaces from acetone/adhesive wash from running down onto the magnets. (you don't want the magnets to have adhesive on them) Tuck a couple of small pieces fine cloth (will soak up acetone/adhesive wash)in the hole (carefully, so you don't tear Mylar any more). What ever happens, just make sure you clean any adhesive off of the magnets before proceeding.

Remove/separate the magnet/Mylar (the metal frame that holds the is the central part of the speaker), separate it from the frame. (MGI's and MGII's, this cannot be done because the metal frame that holds the Mylar is glued to a metal frame, however MGI & MGII improved an newer, this will work).Carefully pry off the metal braces that run across the width of the front side of the speaker (this allows the speaker to curve a little more. Flex the speaker to create an exaggerated arc in the speaker (this will make the Mylar loose across the width of the speaker). This will not damage the speaker. The looser the Mylar is when you fix the hole, the tighter (more responsive) the damaged area will be when the speaker is back together.

Prepare damaged area:

You will be spraying 3M Super 77 spray glue onto the speaker. The goal is to cover the hole in the speaker and the entire speaker minus the one inch border around the hole.

The looser the Mylar, the easier it will be to tuck something between the Mylar and the magnets(I have used a couple of small pieces of plastic bags I cut up and tuck them into the hole carefully ( be sure that no glue will get onto the magnets) Mask off the rest of the speaker with masking tape & newspaper (or if you don't have masking tape, just lay newspaper around the hole and across the speaker).

Trim a piece of strong 3M tape or piece of Mylar if magnepan will supply(trim to cover hole with about . Take some pieces of paper towel or thin plastic, and slide it in the hole - make sure to tuck the edges under the Mylar. Cover the rest of the speaker you don't want sprayed. Spray the 3M super 77 spray glue, wait about 2 minutes, pull out the paper towel/plastic in the hole, and lay down the piece of Mylar / 3M tape(glue side up - not down)stretch it out as much as you can as you lay it down (but be careful not to get your fingers on the glue that is on the Mylar.

Let dry for a few hours. That will do it. However, if your edges are not one inch or so, you could put another piece of Mylar or 3M tape (a little larger piece), and repeat the spray glue and masking (adding a second layer)

Use 3M Spray glue or stronger 3M high strength 90 spray glue to re-attach the metal braces (use C - clamps to hold each side of the metal braces as they dry. Wait at least 1 minute after you spray the surfaces before putting on each metal brace. Press on both sides of the speaker (use the palm of your hand on the Mylar side)to get a good contact across the metal brace.

After a 1 - 2 of minutes, remove most of the pressure on each C - clamp to allow the metal brace to pull away from the speaker on each side ( about ¹/16 of an inch or a touch more ). This will allow for the normal arc of the speaker. If you do not allow for this, the Mylar will be too close to the magnets in the middle of the speaker, and you will get a flapping sound at medium to higher volumes. I spoke with Steve Winey (the son of the founder of Magnepan), and he explained the need for this arc in the speaker.

Your repaired area will now be taught as the rest of the Mylar.

Re-attach the wires by running direct current though the speaker ( 12 Volts at 1.75 - if you are just rewiring the tweeter, and about 2.5 - 3 amps if your running it through the whole speaker).

With the power supply on, put the wires back where they were. They should want to jump back into place with the power on.

Since you have the speaker in this position, it would be good to check it for corrosion of the tweeter and or mid/base wires. Look for any areas that appear to be whiter in color, and/or slightly expanded without a sharp distinct edge all the way up and down the length of the speaker. If you see any suspect areas, these will likely cause a break in the circuit, causing the speaker to go dead, or loose your tweeter (if the problem is in the tweeter wire) down the road in a few years, but if it isn't broken, don't fix it, just something to keep in mind.

You can wipe acetone up and down the length of the speaker to remove as much of the old adhesive as you like (feel comfortable removing). Keep in mind you will be making much of the wire loose on the Mylar (not to worry). This will help to keep the mass as low as possible.

Allow the acetone / old adhesive time to dry (an hour or so).

Turn the power supply (connect the speaker to the power supply with speaker wire. Position all wires to be sure they are between the magnets.

Paint on the Milloxane covering both sides of the wires down the length of the speaker (start out liberally, but spread out the milloxane so it is a thin coat everywhere) and at the ends you can be a little less conservative.

Note: Tweeter Area - use less Milloxane to keep the mass down, but be sure to coat thoroughly.

Keep the current on as the milloxane dries. (About 1 hour).

That should do it.

Test the speaker after the milloxane dries overnight. If you have any buzzing sound at higher volumes, the wires are loose somewhere. Put on a second coat of Milloxane. No need to hook up power supply here.

If you hear flapping at higher volumes, the metal braces are on too tight (the arc in the speaker is too flat). If you followed the directions, this is not likely, but if you are getting it, just remove the metal frame with the Mylar/magnets from the outer frame again. Carefully pry the ends of each metal brace away from the frame (use a flat screwdriver). Make the gap at each end about ¹/16 - ⅛ inch. Be careful not to pull the whole brace off as you pry off the ends.

Put the speaker back together, test again, and that will take care of it.

Use the staple gun to put the socks back on, and enjoy.

Good Luck

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