Marantz 18 top and bottom panels

[WABrown]

I just picked up a Marantz 18 receiver that was missing the top and bottom panels.
I need to make some panels from sheet metal for the bottom and perforated metal for the top, but I don't know how thick the metal is on the original receiver.

Does someone have their 18 apart for repair and can they measure the thickness of the metal with a set of calipers? That would allow me to get this receiver buttoned up! I appreciate anyone who can help.

Thanks

 

[txturbo]

The top is 1.4 mm thick. 410 mm wide and 350 mm deep. The metal has a step up near the front of the receiver at about 13 mm before the front the step is about 1.5 mm. Each hole in the top is 3mm in diameter.

The bottom panel is the same thickness as the top and also 410 by 350. The bottom panel is vented on the left and right under the amp sections. There is another vent at the back of the panel to the right rear of the transformer. If you look at the receiver you can see the same vent holes in the plate that separates the top and bottom sections.

 

[WABrown]

Thank you for the very informative response to my question. I really appreciate the photos of the bottom cover! (Not many pictures of the bottom are out there on the internet for me to copy)

The cover is identified as 1.4 mm thick. As this receiver was made in the US and not Japan, it would have been made to commonly available US sheet metal thickness. The most commonly used steel is either 0.050” thick or just over 0.060” thick. Unfortunately, 1.4mm lands right in between at 0.055” so I don’t know if this is .050 or ~.060. After you gave me such a complete answer I am reluctant to ask you if you could measure the thickness in Imperial measurements instead of metric, but could you?

 

[txturbo]

Looks like it measures .053 with paint. So .050 is probably accurate. Measuring in multiple places caused the reading to change a bit.

Are you going to laser cut new ones?

 

[WABrown]

Yes, you are correct, the paint will add thickness so the panels are 0.050" or 18 gauge steel. Thanks for the measurement!

I was going to use standard perforated sheet metal for the top, Marantz used industry standards for hole diameter and hole spacing so that one is easy. The bottom panel I just planned to do layout direct on the metal and drill the holes in a vertical mill with a digital readout to keep the holes in proper alignment.

You have given me the key measurements for the grill openings on the bottom panel and additional details with the reinforcements, the screw holes for the transformer, and the glued on padding. This is very much appreciated as I don't think I will be running across any one with loose panels to sell so I have to make my own.

 

[txturbo]

You may want to send a PM to tonebells. He had at least one parts unit.

 

[tonebells]

I have more than one unit that also need tops and or bottoms. I did some work in Freecad to lay some out but got distracted. McNichols has what seems to be the correct material for the top cover.

Tony