ZEUS121996 Posted July 4, 2016 Share Posted July 4, 2016 (edited) So I have torn down the pair of 73 K horns I have and plan on using 1" MDF to enclose the backs. Much more rigid than 3/4 BB, I used 3/4" ply before to see if I like what I heard and I really liked the result, the downside was regular ply needs additional bracing, the MDF should probably not move at all. The previous owners upgraded? around 1998 I think (the date is written on the tweeters in Sharpie) Whoever did the work used any and all types of screws to put them back together after reveneering them. The question I have is two fold. I plan on painting the MDF flat black, I was thinking of painting the whole inside of the tophat black, or I can try and strip the brown paint that I think is covering the walnut veneer. Here's a pic of the tophat disassembled. What say yee forum friends? TY Mark Edited July 4, 2016 by ZEUS121996 Quote Link to comment Share on other sites More sharing options...
jimjimbo Posted July 4, 2016 Share Posted July 4, 2016 Why waste your time painting the inside? Quote Link to comment Share on other sites More sharing options...
wvu80 Posted July 4, 2016 Share Posted July 4, 2016 (edited) Wow, one-inch MDF! That ought to add some rigidity, not to mention some weight to those Khorns! If you are going to Paint It Black (ahem) , I suggest satin black instead of flat. I recently used Krylon Cover MAXX in black/satin (paint and primer combined) and really liked it. Coverage was excellent, especially the second coat. The nozzle was high quality with a wide swath, very even spray pattern and dries very even. If you can find it there is a can which is 15 oz that boasts "25%" more" on the big yellow banner around the top. http://www.walmart.com/ip/Krylon-CoverMaxx-Spray-Paint-Satin-Black/43089477?action=product_interest&action_type=title&item_id=43089477&placement_id=irs-2-m2&strategy=PWVAV&visitor_id&category=&client_guid=35ff37b6-cd61-466a-8a1a-33b708038cae&customer_id_enc&config_id=2&parent_item_id=43089479&parent_anchor_item_id=43089479&guid=841d82bc-f97f-4172-9e89-f1356bd15224&bucket_id=irsbucketdefault&beacon_version=1.0.1&findingMethod=p13n Edited July 4, 2016 by wvu80 Quote Link to comment Share on other sites More sharing options...
ZEUS121996 Posted July 5, 2016 Author Share Posted July 5, 2016 Why waste your time painting the inside? The walnut where the crossover is looks great, it still needs more oil and steel wool. The section painted brown (the upright supports and bottom side of hat)) was so poorly done, I can't stand what little of it I can see. They aren't perfect, and I don't look at the backs so maybe I'm putting in work I don't need to Mark Quote Link to comment Share on other sites More sharing options...
jimjimbo Posted July 5, 2016 Share Posted July 5, 2016 Yes, put time, money, and effort elsewhere on those babies! Quote Link to comment Share on other sites More sharing options...
Deang Posted July 5, 2016 Share Posted July 5, 2016 MDF doesn't hold glue nearly as well as 7-ply baltic birch. You probably already know this, but make sure the panels are attached to the outside part of the top hat, not underneath it. Quote Link to comment Share on other sites More sharing options...
ricktate Posted July 5, 2016 Share Posted July 5, 2016 Since they are 73s i would test the air tightness of the back air chamber. I did this on my 72s and found air leaks but it is pretty easy to fix. The test is pretty easy to do also i have posted it before if you cant find it PM me... kind of hard to explain on here. I also sanded and painted the mid horn inside and out with rustoleum black enamel which also cut down on the ringing of the horn a lot. Do you plan to re do the crossovers? Quote Link to comment Share on other sites More sharing options...
wvu80 Posted July 5, 2016 Share Posted July 5, 2016 I also sanded and painted the mid horn inside and out with rustoleum black enamel which also cut down on the ringing of the horn a lot. Do you plan to re do the crossovers? Rick it sounds like your plan with the paint was to damp the horn. Are you saying a simple painting of the horn was enough to produce an audible difference? I would think that applying some sort of material like Dynamat would be more effective if damping was the goal. I'm asking because I have seen where a few people have applied an external damping material, but not everybody with Khorns seems to do this, even though the mid-horn "ringing" is an audible problem most can hear. Quote Link to comment Share on other sites More sharing options...
Deang Posted July 5, 2016 Share Posted July 5, 2016 It only "rings" if it's not attached to the motor-board. Quote Link to comment Share on other sites More sharing options...
ricktate Posted July 5, 2016 Share Posted July 5, 2016 Well it does damp it some......that enamel is pretty tough much better than spray. I used the liquid type and brushed it on. Its very messy but it looks awesome when done. Took 3 coats and sanding and practice to get it to stay smooth. I also did the outside sides and backs with it and some of the inside of bass chamber with it. I did test ringing with it un mounted and it was different than the non-painted one so yes it does work. I also did my scalas same way pics of them are on forum somewhere. The hard part is doing the throat of the horn I taped a small brush on a dowel rod to get in there. I would check all 80s and before bass chambers for air tightness maybe even newer ones also . I only decided to check it cause I was waiting for paint to dry and thought of the way to do it. Mine had a pretty big leak not sure how much it would affect the sound but I'm sure its suppose to be airtight. Quote Link to comment Share on other sites More sharing options...
ZEUS121996 Posted July 5, 2016 Author Share Posted July 5, 2016 The plan is to fill all the joints with wood glue and replace the gasket on the bass bin. The previous owners had Solen caps installed, they sound good, maybe I will recap them since the Solens are from 98. They also had the horns covered with dynamat so I think I'm good to go on that. They have a couple of deep scratches that I need to address. The putty I have matched pretty well, the problem is when I oil them, the putty comes out, so I'm looking for a hardener that wont affect the look Mark Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.