sealing piezos

[fender3x]

I used weather stripping to seal the piezos on my O10, but I have noticed that they rattle at high volumes. I duratex'd the front of the cab, then put weatherstripping around the holes to seal them. Maybe it worked and the piezos just rattle...but as I work on a DR250, on which I plan to have two rows of 6 piezos...I have begun to wonder if there is a better way of sealing them.

Aside from carpet, what have others used? Paint and weatherstrip is one option, but has anyone had good luck with something else?

[Bill Fitzmaurice]

I seal mine with either holt-melt glue or silicone caulk, on the exterior of the joint, so it can be removed if it's ever necessary to swap out the woofer. I also seal the connectors on the back of the piezos w/hot melt, after soldering the wire, so they can't rattle. If the element housing joint is the least bit suspect glue it to the horn when you glue the individual units together.

[fender3x]

I seal mine with either holt-melt glue or silicone caulk, on the exterior of the joint, so it can be removed if it's ever necessary to swap out the woofer. I also seal the connectors on the back of the piezos w/hot melt, after soldering the wire, so they can't rattle. If the element housing joint is the least bit suspect glue it to the horn when you glue the individual units together.

Calk would certainly be the easiest...but I thought that the fumes might harm the woofer?

[Bill Fitzmaurice]

Calk would certainly be the easiest...but I thought that the fumes might harm the woofer?

Not on the exterior of the cab.

[chad]

I use DAP "Seal 'n' Peel" removeable silicone wheather stripping. I put it on the cab, then push the tweeter banks on it and pop some screws in to hold it together, works like a charm. As easy as regular caulk with the advantage that it peels right off. I have been using my cabs this way for almost 2 years with no ill effects.

[fender3x]

Thanks for the responses...I will look for the DAP product!

Bill, I was not a bit confident that I would be able to cut and glue tweeters, which is part of the reason I got 1005 tweeters... I figured 12 would go in without cutting and gluing... I now see that most people who use these do at least some cutting and gluing.

So, I got out my abrasive blade and my BFD panel cutting jig and some old Pyle tweeters that I never intend to use for anything, and did a little experimenting.

The good news is that getting a good, clean cut with the abrasive blade is easier than I thought. Also, the glue-up with hot melt seemed to work pretty well (I assume you use the "low" temp setting?).

However, "rub" came when I used 150 grit sandpaper on the seams (pardon the pun). That left scratch marks in the plastic all over the place.



How do you deal with that? Do you paint the edges? I have thought about masking taping the horn mouths, and spray painting the frames with gloss or semi gloss black paint...but I am curious how others have dealt with this?

[Art Coates]

I spray paint mine. Don't even bother with masking.

[LelandCrooks]

I do mask mine. Maybe not necessary. Sand again with 220g wet or dry. Then spray with flat or satin black. It will look great.

[fender3x]

OK, off to buy some 220 sandpaper in the morning.

I spray paint mine. Don't even bother with masking.

Art, you don't worry about paint in the little holes and on the piezo element?

Thanks for the suggestions!

[DAVID_L_PERRY]

Remove the element when you are working on the piezo assembly. Its just three srews and saves you a world of trouble...

Surely I am not the only one who does this ???

You have no idea what crap is getting into the element if you dont...

Dave

[fender3x]

Oops...editing error...see below.

[fender3x]

I worried that I might not get it together and sealed correctly after taking it apart. I thought it might be possible to get a rattle from that, but...

Since I have had rattles in my O10 piezos, I have have gotten into the weird habit of shaking my piezos hard before final selection. What I have discovered in doing so is that a few had rattles in them, and at least one had a little ball of solder rolling around on the inside. Those piezo's I had to take apart anyway, just to see if there were any foreign objects inside them.

...So I may do as you suggest, Dave. Easier to change the element than the array if there's a bad one. And easiest to keep the gunk out if I only put them in once the cutting, sanding and painting is done.

[Bill Fitzmaurice]

However, "rub" came when I used 150 grit sandpaper on the seams (pardon the pun). That left scratch marks in the plastic all over the place.


How do you deal with that? Do you paint the edges? I have thought about masking taping the horn mouths, and spray painting the frames with gloss or semi gloss black paint...but I am curious how others have dealt with this?

150 grit is way too much, I use 320. You can get an excellent finish by spraying the assembly with Duratex, just remove the elements first.

[fender3x]

150 grit is way too much, I use 320. You can get an excellent finish by spraying the assembly with Duratex, just remove the elements first.

Tried the 220, will try the 320 now... I thought about duratex... I am a roller guy though... No spray apparatus. Think that'd work?

One other question... Do you now use hot melt glue to join them? Or do you use ABS cement as in the plans? Or both?

[Bill Fitzmaurice]

Tried the 220, will try the 320 now... I thought about duratex... I am a roller guy though... No spray apparatus. Think that'd work?

On the frame face, yes.