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Plastic_Spider
12-04-2020, 06:37 AM
My Brother-In-Law has a set of Apollo C51 Speakers and he recently moved. The movers broke one of his speaker grills so he asked if I could make him some. This is what I came up with. He pointed me to this forum and said i should post some pictures and get people's thoughts on whether they are something folks would want. Therefore, if anyone has any comments of feedback, please let me know. These are cut from 1/4" Luaun Plywood. I used my Brother-In-Law's speaker grills to draw the CAD of the grills before cutting them.
The first picture is a sample I cut to compare to the grills, the second picture is the sample laying on top of a grill and the 3rd picture is the freshly cut grills laying on top of one of the speaker grills. They still need to be completed and stained to match.
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hoschibill
12-04-2020, 08:26 AM
Hello :)
This looks very good. What types of wood can they be made from?

JeffW
12-04-2020, 08:27 AM
That's nice work! I bet more than a few of those grills are broken out in the wild, but no idea if there would be enough of a market to produce them.

Plastic_Spider
12-04-2020, 08:36 AM
Hello :)
This looks very good. What types of wood can they be made from?

Hi Oliver,
They can be made from pretty much any wood. A type of plywood would be best from a strength standpoint. I am not sure what would be the best to make them from but imagine once stained to match they will be virtually indistinguishable from a couple of feet away.

Plastic_Spider
12-04-2020, 08:38 AM
That's nice work! I bet more than a few of those grills are broken out in the wild, but no idea if there would be enough of a market to produce them.

Thanks Jeff,
Yeah, I agree and this is why I made the post. They probably would not be that bad to produce as required and I am looking at cutting some with the frames as part of the cut to see how they look and hold up. I am in the middle of changing my shop around so it will be a week or two before I can cut some more.

Mr. Widget
12-04-2020, 08:52 AM
In addition to several JBL models that used this pattern, there are similar fretwork grilles in a number of Altec speakers. The CAD work would be different for the Altecs, but you might be able to make a small side business becoming the “fretwork grille guy”.

True this isn’t a dozens of pieces a week sort of operation, but if your overhead isn’t too high, it might make sense.

Thanks for sharing, please keep us posted, and good luck!


Widget

Plastic_Spider
12-04-2020, 09:04 AM
In addition to several JBL models that used this pattern, there are similar fretwork grilles in a number of Altec speakers. The CAD work would be different for the Altecs, but you might be able to make a small side business becoming the “fretwork grille guy”.

True this isn’t a dozens of pieces a week sort of operation, but if your overhead isn’t too high, it might make sense.

Thanks for sharing, please keep us posted, and good luck!


Widget

I'd be willing to work with anyone to come up with other patterns for different speakers, I would just need to know what the variations are and how they match up with different models. I personally am not familiar with these speakers but can certainly match anything out there. I did notice with my Brother in Laws speakers that the dimensions are +/- about 1mm to 1.5mm between each speaker based them looking to be hand made so anything I match would be within that tolerance unless I was given exact dimensions for each grill. As I posted previously I am in the process of re-arranging my shop so its going to be a couple of weeks before I can do any cutting but I am based in NC and if someone was to send me a sample or very exact dimensions I can draw it in CAD and cut it. My actual business is custom cut Carbon Fiber on a CNC Router for commercial robotics and drones and various other things.

Pellets
12-04-2020, 12:38 PM
Wow! I´m impressed with your work however you did it. Some stories around these grilles:

The grille pattern can be found in Japan, where you have the old trade of manufacturing wooden grilles in different patterns. There are some videos on Youtube showing the techniques of hand carving self-locking patterns. Sharp tools and patience are involved! This particular pattern is called Shippo, or the Seven Treasures. If you take the grille apart you see how delicate it is and how it interlocks without any glue.

I was lucky to buy two unfinished grilles for my home made Apollos way back in the sixties from JBL. The fretworks came from a sub supplier somewhere in the Orient. I even got two cups of stain sent to me after complaining that JBL didn't have a color brochure showing the right tint of the grilles. When I bought my Olympus speakers some years ago I noticed that the fretworks have the same pattern but the sizes are not the same as on later grilles. The early fretworks have a slightly thinner pattern, as I became aware of when trying to repair some broken parts with leftovers from the grilles I bought from JBL.

With this new technology that you are using things become so much easier!

On the material side, I remember noticing a peculiar smell from the fresh wooden grilles and I've been pondering what it could be over the years. My guess is that the wood is Japanese cedar, which is somewhat similar to Canadian white cedar. And if you look at the drawings for the Apollo you see that the upper, lower and mid posts are made from pine.

When colouring the grilles I would recommend using a oil based stain which is easier to work with and also needs just some polishing after drying. The problem is to get the entire thickness (around 1/4 in) stained. Back in the days JBL told me to build a shallow pan, fill it up with the supplied stain and then dip the grilles into it. That would require a quantity of stain that you probably don't have. Maybe the oil stain could be sprayed on.

When selecting stain color you'll obviously try to match the grille that you have on hand. If not, it seems that a light brown color, slightly lighter and more orange than the black walnut veneer seems about right.

Best regards

Plastic_Spider
12-04-2020, 10:17 PM
Wow! I´m impressed with your work however you did it. Some stories around these grilles:

The grille pattern can be found in Japan, where you have the old trade of manufacturing wooden grilles in different patterns. There are some videos on Youtube showing the techniques of hand carving self-locking patterns. Sharp tools and patience are involved! This particular pattern is called Shippo, or the Seven Treasures. If you take the grille apart you see how delicate it is and how it interlocks without any glue.

I was lucky to buy two unfinished grilles for my home made Apollos way back in the sixties from JBL. The fretworks came from a sub supplier somewhere in the Orient. I even got two cups of stain sent to me after complaining that JBL didn't have a color brochure showing the right tint of the grilles. When I bought my Olympus speakers some years ago I noticed that the fretworks have the same pattern but the sizes are not the same as on later grilles. The early fretworks have a slightly thinner pattern, as I became aware of when trying to repair some broken parts with leftovers from the grilles I bought from JBL.

With this new technology that you are using things become so much easier!

On the material side, I remember noticing a peculiar smell from the fresh wooden grilles and I've been pondering what it could be over the years. My guess is that the wood is Japanese cedar, which is somewhat similar to Canadian white cedar. And if you look at the drawings for the Apollo you see that the upper, lower and mid posts are made from pine.

When colouring the grilles I would recommend using a oil based stain which is easier to work with and also needs just some polishing after drying. The problem is to get the entire thickness (around 1/4 in) stained. Back in the days JBL told me to build a shallow pan, fill it up with the supplied stain and then dip the grilles into it. That would require a quantity of stain that you probably don't have. Maybe the oil stain could be sprayed on.

When selecting stain color you'll obviously try to match the grille that you have on hand. If not, it seems that a light brown color, slightly lighter and more orange than the black walnut veneer seems about right.

Best regards


Thanks for the information.
These are cut with a laser cutter. After I get my shop reconfigured I will be cutting some with the frames included in the single part to see how they look.