Hi Everyone,
Working on repowering a Bertram 25.
I have a rotted wood inside the front engine bed. The rotted wood is encapsulated in fiberglass and I plan to open the top and replace the wood with coosa and fiberglass that in.
My question is once I've completed the repair whats the best method of fastening the engine mounts to the engine bed. The original engine mounts were held down with lag screws. Can I use lag screws again or will coosa not hold up to the vibration?
Or should I bolt through with a large washer on the bottom? Access is really limited below the bed and I would have to cut access to thread the nuts on.
See picture below:
https://photos.app.goo.gl/4vUgPk3knyJxpPs97
Bertram 25 Front Engine Mount Bed - How to fasten the engine mount after removing rot.
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- * Bateau Builder - Expert *
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Re: Bertram 25 Front Engine Mount Bed - How to fasten the engine mount after removing rot.
Coosa Bluewater should be fine, not the lower densities. You will need to make the engine bed thick enough to support the lag. So, you cannot drive a 3/8" bolt through 3/4" material, for example. And so, the bond of the coosa is also important. You will have a hard time drilling down the middle of an epoxy bond in two pieces of coosa as the bond will push the drill.
So, some planning of the drilling it important for success. A 3 layer layup of 3/4" coosa would afford you the ability to drill the middle layer without failing...
So, some planning of the drilling it important for success. A 3 layer layup of 3/4" coosa would afford you the ability to drill the middle layer without failing...
Re: Bertram 25 Front Engine Mount Bed - How to fasten the engine mount after removing rot.
Thanks
I just spoke to a coosa sales rep and he recomended to add a backing plate at the back. We're going to use a 1/4" stainless backing and a layer of coosa. Sandwich everytihng with fiberlgass.
Should be buletprrof
I just spoke to a coosa sales rep and he recomended to add a backing plate at the back. We're going to use a 1/4" stainless backing and a layer of coosa. Sandwich everytihng with fiberlgass.
Should be buletprrof
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- * Bateau Builder - Expert *
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- Joined: Tue Jan 12, 2010 12:25 am
Re: Bertram 25 Front Engine Mount Bed - How to fasten the engine mount after removing rot.
Can you explain that better for others? What is the back?
Re: Bertram 25 Front Engine Mount Bed - How to fasten the engine mount after removing rot.
Add 1/4" stainless steel sheet below the coosa into which lag screws will be able to bite into. The 1/4 plate will have to be pilot drilled to get into it.
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- * Bateau Builder - Expert *
- Posts: 10203
- Joined: Tue Jan 12, 2010 12:25 am
Re: Bertram 25 Front Engine Mount Bed - How to fasten the engine mount after removing rot.
I'd probably use 1/4" stainless angle, bolt through glassed coosa on the sides and there is a tapped hole on top.
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