Refoaming FAQ:

Refoaming is the replacement of the cone edge that attaches to the speaker frame. It does not return the speaker to new as reconing does, but it is a less expensive speaker repair option that works well in most circumstances. Send us your repair or  DIY Foams: 3-5″ /  6-8″ /  9-10″ / 11-12″ /  14-15″ /  18″ or Compare Sizes REFOAM KIT- SPEC SHEET (PDF)

Instructions /  Need Smaller Size" / How to Measure Foam /  HOW TO Section

How do I know if I need flat, angle or straight attach foam"

There are three ways the foam surround can attach to the cone: flat, angle or straight. If the outside edge of the cone has a flat lip that the foam will attach to then you need the flat foam. If the foam attaches at a slight angle to the cone without the lip, then you need the angle foam. A third foam has we call a straight attach. There is no seam from the inside of the roll to the inside edge of the foam. These are much harder to use and it will be fine to use the angle attach foam if you want to take the easy way.  Sometimes the sizes for one will work better than the other for a particular application. Either foam will work in place of the other, but using a flat foam on an angled cone (or vice-a-versa) just makes the attachment process a little bit more difficult.

 

If I give you my model number, can you tell me what foam I need"

Maybe. If we have documented your model number in OUR database, then it could be the foam you need. Note however it can be a bit more complicated because sometimes different years of production often used different versions of the same model speaker. Those different versions could use different refoam kits. The manufacturers spec sheet does not help. It will tell you the frequency response, power handling, etc, but it will not tell you what the foam surround sizes are. Refoaming only recently became a standard repair due to increased reconing costs and difficult to find replacement options. Manufacturers never intended for their speakers to be refoamed, therefore they never documented the foam sizes.

 

Why do I need the roll info" This is confusing me.

We have been asked for the roll specs. It can be difficult to find the right size foam for your needs. If you can find a foam that closely matches your OD and ID size requirements then whether or not the roll itself is an exact match is not as important. As in everything we do, we began to list the roll info because it was requested. The FOAM OD and ID are the dimensions of the actual surround. The ROLL OD and ID are the dimensions of the curve portion only.

 

Why was my original dustcap different from the one you sent (or used)"

Not all the same size or same material dustcaps are still available so we must use what is currently available or what we feel will fit the cone or voice coil best. We generally send a larger than original dustcap with refoam kits so the new dustcover will cover the original adhesive lines.

 

Why should I replace my dustcaps, they look fine"

There are two parts that help to keep the voice coil centered in the magnetic voice coil gap. One is the spider and the other is the cone. When the surround has deteriorated, we recommend that you cut off the dustcap and use the shims provided with the refoam kit to lock the voice coil-cone assembly in place. This insures that the voice coil remains centered during the refoaming process. (Exceptions to this are Bose 802 or 901’s and Infinity Bullet speakers. These must be refoamed by “ear” and feel.)

 

Why can’t I find the correct foam for my speakers"

Many of the original parts are no longer being made for some of the older model speakers. Sometimes you must use a foam that is slightly larger than the original foam and cut and seam it to become the size you need.

 

How Do I Remove the Old Foam"

We have set up pictures and a tutorial in our How To Section.

 

Should I refoam both my speakers" Only one is bad.

The foam deterioration process tends to happen at relatively the same time. If one appears good now, it will probably show the deterioration in a few days to weeks even though it is actually breaking down now.

 

The dog did it! The baby did it! My teenager turned up the volume!

No, nobody caused this surround deterioration. It is caused by environmental conditions and happens every 5-25 years. Deterioration rates are affected by environmental conditions and where you live. 

 

Can I use a butyl rubber surround instead of foam" I hear it doesn’t dry rot.

The short answer is yes, but not easily.  We are often asked if a butyl rubber surround lasts longer than a polyfoam surround. In reality, it does last longer, but it does dry rot just like the polyfoam. You might gain some time, but some experts believe you will experience a small bass loss as well. It is difficult to find the right size butyl surround and they are  difficult to work with as they don’t hold their shape well and do not adhere well to the cone or frame. Also, bear in mind that if a speaker has been designed for a woofer with a foam surround, if you change the set up, you are changing the factory parameters. If you are determined to have a butyl surround, in most cases, the speaker can be reconed. There are many more cones that come with a butyl edge as opposed to individual butyl surrounds.

 

Why do you send contact glue with your refoam kits instead of the white glue I’ve seen elsewhere"

We have seen other vendors offer a white adhesive for foam attachment. It can be easier to work with because it does not dry as quickly so it gives more “fudge” time. We include a contact glue with our refoam kits. We find that it more closely matches the specifications of the original speaker manufacturers and the adhesion lasts longer.  We use the latex for attaching foams to styrofoam cones and doping or sealing some double roll paper cone edges and cloth surrounds. However, do not follow the instructions on the glue package and spread on both surfaces. Do not apply adhesive to the foam. Applying glue to the foam causes the foam to curl and makes it difficult to attach properly.

 

Can I get the white glue that dries clear with my refoam kits"

Yes we can easily substitute the white latex for the contact glue we normally send with the refoam kits. Simply request it when you place your order.

 

Can I replace my foam surround with butyl rubber"

The short answer is yes, but not easily.  We are often asked if a butyl rubber surround lasts longer than a polyfoam surround. In reality, it does last longer, but it does dry rot just like the polyfoam. You might gain some time, but some experts believe you will experience a small bass loss as well. It is difficult to find the right size butyl surround and they are  difficult to work with as they don’t hold their shape well and do not adhere well to the cone or frame.  Also, bear in mind that if a speaker has been designed for a woofer with a foam surround, if you change the set up, you are changing the factory parameters.  If you are determined to have a butyl surround, in most cases, the speaker can be reconed. There are many more cones that come with a butyl edge as opposed to individual butyl surrounds.

 

What glue should I use if I have a Styrofoam Cone"If you have a syrofoam cone, request the latex for adhesives instead of the contact glue. The contact glue will not work with the styrofoam cone.

 

What do I do if I’m having trouble attaching the foam to my Polypropolene Cone"

It is more difficult to get adhesives to bond to a polypropolene cone than to a standard paper cone. To deal with this, use a Very LIGHT grade sandpaper and scuff the edge of the cone that will attach to the foam to create a better bonding surface for the adhesives.