Mortite Question

Des Moines

I went to Home Depot and Loews to buy Mortite and neither store carried it. HD said they carry GAP instead.

Questions
Do you guys use Mortite cord or is it like a caulk?

Is there another sealant that is equal to mortite for sealing drivers and PRs?

Do you remove the rubber gaskets from tweets and use mortite or do you just make another / better gasket to seal tweets?

jimbo1421

I used Flexible Caulking Cord Weatherstrip from MD Building Products on my vintage Monitors.

http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?jspStoreDir=hdus&catalogId=10053&productId=100353483&navFlow=3&keyword=cord+weatherstrip&langId=-1&searchRedirect=cord+weatherstrip&storeId=10051&endecaDataBean=com.homedepot.sa.el.wc.integration.endeca.EndecaDataBean%409aa976b&ddkey=THDStoreFinder

Jim

schwarcw

Des Moines wrote: »

Do you guys use Mortite cord or is it like a caulk?

I found the Mortite at Home Depot in the section with the insulation. It is a rope cord. Very inexpensive ($5), maybe check some online sources.

Des Moines

Thanks for suggestions guys. I will check the insulation area and if I still cant find it there, I will go with Jims recommendation.

Jim did you remove the tweet gaskets and use mortite cord on the tweeters also?

hearingimpared

Des Moines wrote: »

Thanks for suggestions guys. I will check the insulation area and if I still cant find it there, I will go with Jims recommendation.

Jim did you remove the tweet gaskets and use mortite cord on the tweeters also?

I wouldn't Mortite the tweets. They don't really have a wide flat edge to make the seal. The original gaskets should do just fine.

billbillw

My Home Depot didn't have it and I suspect most won't these days. They have mostly moved to rubber and foam strip type products. I found that ACE hardware sells a product that is nearly identical to Mortite. Just go in and ask for rope caulk.

jimbo1421

Des Moines wrote: »

Thanks for suggestions guys. I will check the insulation area and if I still cant find it there, I will go with Jims recommendation.

Jim did you remove the tweet gaskets and use mortite cord on the tweeters also?

Yes I did. It works fine. Just make sure it is not flattened below the lip on the edge of the tweeter (if it has one).

Jim

hearingimpared

jimbo1421 wrote: »

Yes I did. It works fine. Just make sure it is not flattened below the lip on the edge of the tweeter (if it has one).

Jim

Jim, what kind of tweeters did you Mortite? I found my RD0198s not to have a large enough edge to hold sealer.

DarqueKnight

Des Moines wrote: »

I went to Home Depot and Loews to buy Mortite and neither store carried it. HD said they carry GAP instead.

Mortite seems to be getting hard to find in stores. The Home Depot here stopped carrying it. It is available online from a variety of sources. Shop around as prices can vary a lot.

Des Moines wrote: »

Do you guys use Mortite cord or is it like a caulk?

The box says "Mortite Weatherstrip and Caulking Cord". I sent and inquiry to Polk's customer service asking about replacement driver gaskets and Matthew Polk recommended Mortite as a higher performance alternative to foam rubber gaskets.

There is a picture of the box in post #1 of this thread.[/QUOTE]

Des Moines wrote: »

Is there another sealant that is equal to mortite for sealing drivers and PRs?

I don't know.

If you use another sealant, take care to chose one that forms a semi-rigid seal between the driver rim and the speaker cabinet. You want a semi-rigid seal that is stiff enough to couple the driver to the cabinet, yet just elastic enough to fill in the irregularities in the cabinet where it joins the driver rim. You also want something that sticks to the driver rim and speaker cabinet, yet is easy to remove. Mortite has all these properties.

Des Moines wrote: »

Do you remove the rubber gaskets from tweets and use mortite or do you just make another / better gasket to seal tweets?

I used a stacked, double bead of Mortite just inside the tweeter rim. See page 3, post #69 of this thread for a picture.

Des Moines

Thanks everyone for your comments and suggestions.

Thanks for the thread link DK!! Very Helpful review!

kcoc321

I have used the same MD brand that Jim linked. I think it works great but I have never seen 'real' Mortite, so I am just going off of the properties. It remains flexible, and yet forms a bond. And yes, I took off the old foam gasket, as keeping it on would defeat the purpose of the "Mortite"/ rope caulk.

jimbo1421

hearingimpared wrote: »

Jim, what kind of tweeters did you Mortite? I found my RD0198s not to have a large enough edge to hold sealer.

I have done Peerless & SL-1000 which have a face plate that is flat on the inside. I flatten the cord a bit by rolling a dowel on it. On the RDO-194, unlike Darque Knight, I just used one strip of cord inside the lip and made sure that I did not compress the cord below the lip. It still passes the press test. I thought that two layers was too much of a build up and that the face plates tend to distort more easily when screwed on.

Jim

hearingimpared

Des Moines wrote: »

Is there another sealant that is equal to mortite for sealing drivers and PRs?

DarqueKnight wrote: »

I don't know.

If you use another sealant, take care to chose one that forms a semi-rigid seal between the driver rim and the speaker cabinet. You want a semi-rigid seal that is stiff enough to couple the driver to the cabinet, yet just elastic enough to fill in the irregularities in the cabinet where it joins the driver rim. You also want something that sticks to the driver rim and speaker cabinet, yet is easy to remove. Mortite has all these properties.

Before DarqueKnight used Mortite and posted his "how to" thread, I used Parts Express Speaker Caulk (black) to seal my MWs, PRs and to repair a split in the seam of one of the cabinets. It works really well and is very easy to handle and apply. You can get it here;

http://www.parts-express.com/pe/pshowdetl.cfm?&DID=7&Partnumber=269-300&ctab=13#Tabs

Follow the instructions in DarqueKnight's thread to apply the speaker sealer.

http://www.polkaudio.com/forums/showthread.php?t=74524

hearingimpared

jimbo1421 wrote: »

I have done Peerless & SL-1000 which have a face plate that is flat on the inside. I flatten the cord a bit by rolling a dowel on it. On the RDO-194, unlike Darque Knight, I just used one strip of cord inside the lip and made sure that I did not compress the cord below the lip. It still passes the press test. I thought that two layers was too much of a build up and that the face plates tend to distort more easily when screwed on.

Jim

Thanks Jim. I did my MWs & PRs with Parts Express Speaker Caulk before DarqueKnight's Mortite thread was posted. I had a hell of a time trying to use the PE Caulk (which is pretty much the same consistency as Mortite) on my RD0198s so I just skipped and used the original gasket. That's why I recommended not doing the tweeters. I'm glad you were able to set Des Moines straight. Good deal. I'm going to give my RD0198s another shot using your method. Thanks again.