rear corners

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ford351c594
Posts: 142
Joined: Jul 16th, '16, 17:01
Location: New Orleans

rear corners

Post by ford351c594 »

Good morning. its been a while. I have finally recovered from yet another knee surgery and slow started putting boat back together.... made new struts and mounts and rebuilt the swim deck. When I attached the starboard side the corner just collapsed. The port side was strong as can be. Is this a Bertram fiberglass design or was it added to help support the exhaust? Also if it is Bertram made, anyone know if it is "filled" or has wood in there to rot?

now lets see if I can remember how to post a picture....


https://i.imgur.com/siDL7Gf.jpg

https://imgur.com/siDL7Gf
Ryan Randall
73 B28 flybridge
"smart people learn from their mistakes, the smartest people learn from others and their mistakes"
Yannis
Senior Member
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Joined: Oct 23rd, '13, 09:41
Location: Athens, Greece

Re: rear corners

Post by Yannis »

Ryan,

I don't see anything collapsed. Are you sure you put the right pics? An outside pic would also help.
1973 B28 FBC/2007 4LHA STP's - "Phantom Duck" - Hull "BER 00794 1172"
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Tommy
Senior Member
Posts: 1343
Joined: Jun 29th, '06, 13:36

Re: rear corners

Post by Tommy »

Hi Ryan, welcome back and hope your rehab goes well. I agree with Yannis; I don’t see evidence of a structural failure. I do see that the backing plate may not be perfectly level, but can’t imagine that being a problem.

By the way, I’ve got 90K miles on my ‘13 Raptor and still running like a sewing machine. I appreciated the pre-purchase counsel you provided me.
Tooeez
Posts: 266
Joined: Jun 24th, '14, 19:51
Location: Palm City, Fl

Re: rear corners

Post by Tooeez »

I take it you mean when you tightened the backing plate the glass under it crushed. I have the same support pieces, one on each side and one in the middle of the transom. I believe that they are placed to stiffen the transom--it is pretty thin. I don't know what's in those supports, but my flybridge has the same kind of supports on the inside of the forward face, and there is foam inside of them.
ford351c594
Posts: 142
Joined: Jul 16th, '16, 17:01
Location: New Orleans

Re: rear corners

Post by ford351c594 »

Thats great Tommy. They are awesome trucks.


That is the correct part Im taking about. The small build up around the exhaust. On the right side it has zero strength. I barley tighten it and it collapsed. The left side solid as as can be. It doesn't look or seem important, but wanted to make sure. its still supportive of the exhaust, just not at the top where the mount is bolted in. Next I need to remake one of the 4 struts..... apparently I had a brain fart and made one an inch to short........
Ryan Randall
73 B28 flybridge
"smart people learn from their mistakes, the smartest people learn from others and their mistakes"
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JH_B28
Posts: 127
Joined: Aug 16th, '12, 12:31
Location: Salinas, Puerto Rico

Re: rear corners

Post by JH_B28 »

Hi Ryan,

In the 28's bertram put marine ply where the exhausts exit the transom to give it better support (transom glass is thin). I had to replace the rotted wood when I made my new exhaust exits.

I don't have pics of the inside but maybe you can see the wood in the new exhaust cut out:

Image

Image

Hope this helps.

Regards,

Jorge
Jorge E.
1973 Bertram 28'
Yanmar 4LH-STE's
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Tommy
Senior Member
Posts: 1343
Joined: Jun 29th, '06, 13:36

Re: rear corners

Post by Tommy »

Got it, Ryan; with your clarification and Jorge's comments makes sense. Yes, Bertram would provide added support at hull and transom penetrations by glassing in a layer (or layers) of marine plywood. Not unusual in these 40-50 year old boats for water to invade the core of plywood and rot it out leaving an unstructured void. Some of the the plywood covered-by-glass backing pads for the struts have suffered a similar fate. Capt. Pat ground my strut backing plates out and glassed in new, and larger, support pads. My brother and I had a 1968 20' Bertram Sportsman, and the previous owner removed all the rotten transom core (which was marine ply) and completely rebuilt the transom structure from the inside. You may be able to spot grind and rebuild the corner of the backing pad that collapsed as a temporary fix; but I don't think the structural integrity of the hull has been compromised.
ford351c594
Posts: 142
Joined: Jul 16th, '16, 17:01
Location: New Orleans

Re: rear corners

Post by ford351c594 »

Fantastic and thanks for the pics. I will reevaluate it when I can get back to the boat........ Probably going to run to the shop later this week to make the struts and then I'll start with new bilge bumps and installing the new aluminum fuel tank....... Then I can start the new engines from 2.5 years ago......
Ryan Randall
73 B28 flybridge
"smart people learn from their mistakes, the smartest people learn from others and their mistakes"
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