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Discussion Starter #1
I managed to snag a pair of rare Cornwall Decorator speakers from Craigslist for a ridiculous price. A year ago I documented the refinishing job on a pair of Klipsch Heresy speakers that were finished in Waterfall Bubinga. This time I wanted to use Santos Rosewood, using the hot glue method.



These are the Decorators finished in a Walnut stain that did not hold up well. The dust covers on the woofers were eaten by a dog.

Below is a practice project using bookmatching and the hot glue method.






 

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If you haven't started yet consider some upgrades to the cab. Internal cross-bracing and modern crossovers are a must, as is remounting the mid and HF horns from the front of the baffle. The original EV horns are diffraction horns that should be vertically aligned. PK never did come up with a logical answer why he didn't do so.
 

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Each veneer has different characteristics. The Bubinga and Walnut Burl were relatively easy to work with. I did not have problems with splintering or checking. They were easily finished in Tung oil. Santos Rosewood has proven to be more difficult to work with.

Before getting too deep into a project I always start with a smaller project. In this case refinishing the base.









I usually finish my projects in Tung oil. Do not try Tung oil on Santos Rosewood. The wood is very oily to start with and the oil is not evenly distributed in the veneer. This led to a sticky, gummy mess. Sanded them down and finished the bases in a semi-gloss brush on lacquer.



Woofers were repaired with new dust caps and paint.

 

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Discussion Starter #4
Let's tackle the big stuff. Applying glue.



Cutting raw veneer.



Bookmatching.



Gluing the veneer. Note tape along 3 sides. This minimizes curling.



Ironing the first piece of veneer down.



Ironing the second piece down. Notice the 1/8" bar and tape.

Steps in making a tight joint.

1. Iron down veneer piece one. We made a pencil mark on both sides to line the veneer up.
2. Place an 1/8" rod about an inch from the joint.
3. Tape the second piece of veneer to the first piece.
4. Iron up to about 2" of the joint.
5. Remove the rod.
6. Iron toward the joint to make a tightly compressed joint.





You can see the buckle in the veneer created by the wire.



The center joint.



Finished side.

 

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Discussion Starter #5
Santos Rosewood has some undesirable qualities that has given me some headaches.

I have a problem with checking (cracks along the grain). What I have done to minimize the checking is to be careful with the amount of glue used, veneer tape on any places that might check. Since the veneer is bookmatched one of the pieces will tend to check more. When veneer is rotary cut minute breaks or splits known as lather checks are apparent on the concave side. This is commonly referred to as the "loose" side as opposed to the "tight" or convex side. I found a veneer conditioner that has helped somewhat. The veneer and substrate are stored in the same room, 78 degrees, and 50% humidity. The photo shows a check that I highlighted with water so you can see it better (circled in blue).

The compressed joints have proven to be difficult. I use the 1/8" rod but can't seem to get the joint perfect from end to end. Allow 2" from joint to remain untacked down, allow the tacked down veneer to cool (don't want it to move). Start from the middle, work to the right (I am right handed) get that side down pretty good but notice the left side has opened up some despite taping it together. We are talking about 1/32" but it seems like the Grand Canyon to me. Fortunately it can be fixed by gluing a sliver in the gap. Once sanded you can't see it unless you know what you are looking for. The top of the picture has a perfect compressed joint.

I'm hoping things start to move faster now that I have a lot of the problems figured out.



Here is a repaired joint.

 

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Discussion Starter #6
If you haven't started yet consider some upgrades to the cab. Internal cross-bracing and modern crossovers are a must, as is remounting the mid and HF horns from the front of the baffle. The original EV horns are diffraction horns that should be vertically aligned. PK never did come up with a logical answer why he didn't do so.
Crossovers have been redone. The only thing needed were new capacitors. Spent some time in Hope a couple of years ago with one of the Klipsch engineers testing the original Cornwall crossovers in the anechoic chamber. PWK did a fine job with his design.

I am considering adding additional bracing to the cabinet.

What could make the most difference is raising the woofer a couple of inches. It would be more in line with the Cornwall III design. Unfortunately it would detract from the look of the 1976 Decorators.
 

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Discussion Starter #7
Here's how crazy I get with the tape.



To be continued.
 

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Discussion Starter #9
Finished the sides and tops. I used the quarter matching technique. Looks as if the veneer softener worked. Checks are under control, center joint looks to be tight. Sure looks messy with all the tape. That's the poor man's version of paper backed veneer. I had to peal back some tape to line up my joints.

BTW the checks and less than perfect center joints are all on the bottom of the speakers.



Time to turn my attention to the front of the speakers. Need four sheets of veneer. Take the two center pieces and cut them in two length wise, book match them, and have the two edges book match the outside edges of the two center pieces. Now I have 3 joints to work with.
 

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Discussion Starter #10
Here is how I shot the edges of the veneer so they fit tightly together.




Here is one speaker reskinned.




Second face laid out.




Edge shot of completed speaker. Note how the grain wraps around both sides and the top.



Left side of speaker.

 

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Oops...checking too severe on one top and side of same speaker. Sanded to glue line and started over. More to come.
 

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Discussion Starter #13
Checking of the veneer continued to vex me. My solution...more tape.


Seemed to work OK. Because of the checking I sanded down a top and a side and started over. Speakers are now sanded to 220 grit, cracks are filled and in some cases painted, waiting on 320 final sanding and sanding sealer. Cracks (checks) were filled with Mahogany colored filler or crazy glue with sawdust. Grain and background painted with a combination of yellow ochre, burnt umber, and burnt sienna.



The bases were completed using semi-gloss brushing lacquer, 320, 400, 600, 2000 self lubricating sandpaper (soapy water). Rubbed with a combination of Pumice (FF), paraffin oil and a cork sanding block. Final rub used Rotten stone, paraffin oil, and a felt sanding block. The rest of the speakers will be finished in the same way.

It will be over a month before these babies are done. Takes a month for the Lacquer to cure and take a rub down.
 

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Discussion Starter #14
Project is now complete. The cabinets were finished with sanding sealer and up to 8 coats of brush on semi-gloss lacquer. The lacquer was allowed to cure a month, sanded with 320 wet/dry sandpaper. At that time I did not like how some of the imperfections were filled (or not filled) by the lacquer, so applied a couple of more coats. I also used a small artist brush to add extra lacquer to some problem areas. Waited another month. Finished with 320, 400, 600, 800, 2000, and rotten stone. Applied paste furniture wax as a last step. They are now sitting in the front room hooked to an old Carver preamp and amp. Will try the MAC1700 soon. Not too happy with the Carver's.



 
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