What is inside the stringers?

[tonyiiiafl]

1994 Carver 390 CPMY. I am mounting a Fireboy automatic fire extinguisher. It must be mounted upright, not horizontal. Anyway the only place I can mount it is against the port stringer in front of the port engine. I drilled a hole in the top of the stringer and used a scope to check what was inside and it was clean and clear. SO…….I drilled a hole about 4” from the bottom, and after I went through the fiberglass, (1/2” or so thick) The drill stopped and I saw metal/steel shavings and I stopped. Is there a steel plate inside the stringers? I also thought about making a bracket of 1/4” steel with a 90 degree bend at the top, then run it down to the where the hull mergers the stringer. then mount the backer onto the bracket..

Any opinions or does anyone know what is inside the stringers?

best always……

Tony

[KyleR]

Yes, typically there is a metal bar(s) that is embedded in the "engine" stringers to give the engine mounts something solid to attach to.

[tonyiiiafl]

Well, that is good to hear.! Now what are the thoughts of drilling 3 holes through it, adding 3 5/16" HD molly bolts to hold the FIREBOT in place, or go with the bracket I was thinking of and mounting it from the top with 2 HD molly bolts>

[Cooler]

I would think either is fine, but hanging anything usually presents the risk of falling. The hull under that area is solid, and at least 2" thick, so lot of structural integrity there. Also, just FYI, my Fireboy is mounted at an angle (approx 30 degrees) from the factory. So it probably does not need straight vertical mount. er

[tonyiiiafl]

My older HALON system is mounted at a 45 degree angle also. If I mounted it at an angle I would have the room where it is now. I do believe if I used the 5/16” moly bolts into the top of the stringer and that bracket of 1/4” x 2” flat stock and put it against the bottom of the hull with a piece of rubber under it it would be solid., I wished this were easier!

Thank you

[tonyiiiafl]

I spoke with Xintrex. They said I can mount it at up to a 35 egress angle. The original Halon system was mounted at the front bulkhead, in front of the genset. I have 2 choices, the bracket I mentioned, or I can move the dry bilge pump and mount forward at a slight angle. I can through bolt the bracket through the bulkhead, which back the kitchen cabinet. It will be more port than centre, but the other original one was blocked by the genset….don’t know why my photos are off by 90 degrees

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