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BeAll--rtram 31 hull thickness

Posted: Jun 28th, '17, 17:00
by Amberjack
Hello

Re: Bertram 31 hull thickness

Posted: Jun 28th, '17, 17:04
by Amberjack
Let me try again....

Can anyone tell me how thick our hulls are at the raw water intake? I'm installing exterior sea strainers and when we took the original clam shells off the machine screws they had used were only penetrating 1/4". I want to go longer but don't want to penetrate the hull.

Re: BeAll--rtram 31 hull thickness

Posted: Jun 28th, '17, 17:10
by Bruce
Depends on year but the average I found was about 3/8".

Re: BeAll--rtram 31 hull thickness

Posted: Jun 28th, '17, 20:55
by Tony Meola
Bruce

On my 75 I have found it different in spots. At least a half on the bottom. Shaft logs were real thin before the repower. I would guess the pre 73's hulls are a lot thicker.

Re: BeAll--rtram 31 hull thickness

Posted: Jun 30th, '17, 06:04
by Bruce
Your right Tony, early boats were thicker.

Re: BeAll--rtram 31 hull thickness

Posted: Jun 30th, '17, 09:14
by my other east
I just drilled a hole for a new transducer under the companion way, and it was 1/2 in thick.
about 5 inches up and away from the keel, and this is on a 74

Re: BeAll--rtram 31 hull thickness

Posted: Jun 30th, '17, 09:30
by my other east
remember too AJ, that you should drill atleast one screw hole thru the hull for each strainer, and tie it to your bonding system.

Re: BeAll--rtram 31 hull thickness

Posted: Jun 30th, '17, 12:53
by Amberjack
Thank you all for the helpful input, this turned out to be more of a project than anticipated. Per Captain Patrick's instructions I planned to through bolt at least the leading corner of the external strainer but when we measured we couldn't be sure that through bolt wouldn't hit a structural member and at the very least it would come through in the engine compartment buried under the transmission.

Screwing into the glass wasn't going to work. The original clam shell strainers were fastened with custom shortened machine screws (!) that penetrated about 1/4 " and I think they were mostly held with bedding compound. The big Groco APHS external strainers would have ripped right off at anything over an idle.

We decided to fabricate a 1/2" "shoe" glassed to the hull and fasten the sea strainer to the shoe. Problem solved! I'll try to get some images today.

Re: BeAll--rtram 31 hull thickness

Posted: Jul 12th, '17, 20:53
by bob lico
two 67,one 71,one 73 and one 79 cut out for transducer same distance from keel 73,71,67 were exactly 3/4" and 79 about 1/16" less .for the record the 79 -38 foot convertible is 5/8" i have a few 2" cut outs you can see but why bother this is exact.

Re: BeAll--rtram 31 hull thickness

Posted: Jul 28th, '17, 07:05
by Bob H.
Resolute is a 66 hull 3/4 or better on the bottom. BH