C35 Grille?

[robertg]

How is the grille fastened on a C35 cabinet? The drawings just show the cabinets and they don't say anything about the grille. I am thinking of making a set, and I want them to look like they came out of the factory.

[Horn Fanatic]

How is the grille fastened on a C35 cabinet? The drawings just show the cabinets and they don't say anything about the grille. I am thinking of making a set, and I want them to look like they came out of the factory.

The C36, C37, and C38 had grilles that slid in though a slot on the bottom of the cabinet, which were kept in place by two wedge shaped wooden blocks screwed in place.
The C35 may have a similar arrangement. It is quite a clever arrangement IMO. The C36 was the first model in that series, followed by the C35.

Unfortunately, the slot is not depicted on these drawings, but rest assure it is there. The slot is between the front edge of the baffle and the back edge of the edge banding.
I built a pair of C38 from that plan about ten years ago.

The last photograph on this page clearly shows the slot, as you can see the carpet through it. I've noticed on some C38 and C35, JBL affixed two wedges on the baffle
to press the grille frame against the back of the edge banding, thereby insuring the grille frame would not rattle.

BTW - Those grille frames were actually window screen frame, which used that continuous grommet to hold the fabric in place in the same manner the screen is held in place.
I tried that method using the grommet insertion tool. It's a bit dicey if you slip with the tool and cut into the fabric. Also, JBL must have used some type of fixture to hole the
grill fabric in place so as to keep the nap straight. For my cabinets I made 1/2 thick Baltic birch frames and staple the fabric. As I have made thousands of grille frames,
it really wasn't much trouble.

http://www.audioheritage.org/vbulletin/showthread.php?13844-C38-Restoration-with-Pics/page2


http://www.lansingheritage.org/images/jbl/plans/c35-c39/page2.jpg

[robertg]

Thanks, that picture makes it a lot clearer. I was going to try to make an exact replica of cabinets made in that era, but I think I'm going to do it different. I'll probably wrap a frame with cloth and hold it in with velcro.

I'm also going to use 1" baltic birch plywood and change the dimensions slightly. I'm thinking of making them a little deeper to compensate for the volume lost by the thicker wood. I'm not sure if that will matter or not?

[robertg]

I found a couple more pictures. Now if I can only find one of the back of the grille. It looks like the grille is recessed about 1 3/4.

[Horn Fanatic]

I found a couple more pictures. Now if I can only find one of the back of the grille. It looks like the grille is recessed about 1 3/4.

In a previous post I stated the frame is of the window screen / screen door type, where the fabric is held in place with a continuous length of rubber grommet that
needs to be inserted with a tool. Personally, I would avoid using that method, as it is a royal pain keeping the fabric nap straight without using some sort of fixturing
to hold the material square to the frame while inserting the grommet. Just make a frame out of 1/2 Baltic birch, and to make it easy, staple the fabric to the front of
the frame and trim off the excess. The staples will be hidden by the front lip.

The only down side of the JBL design, is that the cabinets are made of particle board, and by placing the T-nut to mount the front legs so close to the slot invites
disaster. On my cabinets I moved the fasteners back far enough where the legs do not hang over the slot.

Perhaps you could post photographs of your cabinets when you complete them?

H.F.

[robertg]

In a previous post I stated the frame is of the window screen / screen door type, where the fabric is held in place with a continuous length of rubber grommet that
needs to be inserted with a tool. Personally, I would avoid using that method, as it is a royal pain keeping the fabric nap straight without using some sort of fixturing
to hold the material square to the frame while inserting the grommet. Just make a frame out of 1/2 Baltic birch, and to make it easy, staple the fabric to the front of
the frame and trim off the excess. The staples will be hidden by the front lip.

The only down side of the JBL design, is that the cabinets are made of particle board, and by placing the T-nut to mount the front legs so close to the slot invites
disaster. On my cabinets I moved the fasteners back far enough where the legs do not hang over the slot.

Perhaps you could post photographs of your cabinets when you complete them?

H.F.
Im going to use birch for the frame, it's probably the easiest way to do it. I think I'm going to wrap the cloth around and staple it on the back side of the frame. My cabinets are going to be made out of 1" Baltic birch, so the slot that the frame sits in will only be 1/2" deep, might not be enough to hide the staples.

ill take pictures when it's done, that only if it turns out good. I have the boards cut already, and the big holes cut. I'm just deciding how fancy I want to get with the corner joints. I'm going to screw and glue everything, but I'm not sure if I'm going to router the corners also. I'm covering them with veneer so the screws will be covered, and the 1" plywood shouldn't split.

[SEAWOLF97]

I had C38's ... that bottom MDF with feet mounts screwed in was a problem. The C38's are too heavy to pick up easily to move and if you slide them the feet will buckle and screws pull out of the bottom.
My pair had this happen before I acquired them. PO had set the feet (and the cratered MDF) back in and slobbered with glue. Not real pretty or secure. :eek:
I picked up some 1 inch marine plywood with the intention of painting the edges black, cutting a little smaller than the existing bottoms and then gluing and screwing to make a 2nd bottom to mount the feet into.

Sold the pair before I could to the repair.

[robertg]

I'm half way done. That 1" birch is hard to cut with a router. I made them a little bigger, the outside is 37" x 25" x 17" deep, 6 cubic feet. I'm going to cover them with Walnut veneer, but that is a long way away.

[Wagner]

Beautiful work, very nice, handsome

Thomas Wagner

[robertg]

Almost done, I can't decide what colour cloth I should use. It was a lot more work, and cost a lot more money than I thought it would.

[BMWCCA]

Almost done, I can't decide what colour cloth I should use. It was a lot more work, and cost a lot more money than I thought it would.
But you did amazing work!

FWIW, I like my C35 and C37 with black grilles.

[robertg]

I found some vintage looking material for the grilles, and I'm going to make up another set of black grilles. I'm just waiting for my badges to come in the mail and I'll be done. They sound really good hooked up to my Hafler DH200, but I think I'm going to find an old Mcintosh receiver.