Fiberglass advise; 1997 Bayliner 3988

[scubadiver535]

The captain wants a second helm seat facing forward on the upper helm. I know nothing about fiberglass but do have questions-
1- How thick is the flooring of the upper helm?
2- Pending the answer to #1, would anybody trust 3/8" nut certs to attach 3/4" plywood and the new pedestal?
OR
3- Do I need to remove the salon ceiling vinyl for thru hole backing?

Some vessels have raised plywood (double helm pic) but I can't tell if the plywood is thru hole with backing.
Some vessels have no plywood (twin seats pic) with pedestal only; also can't tell if thru hole backing.

Any feed back will be appreciated.

[Norton_Rider]

We went through the same thing and decided not to drill holes. Instead we got a second helm seat with a pedestal similar to this one. It works on all but the roughest conditions.

[scubadiver535]

Do you remember where you obtained that pedestal?

[Centerline2]

the floor of the flybridge should be layed up with either 5/8 or 3/4 plywood as the core. depending on the footprint of the seat pedestal, a backer may not be needed.... its common for helm seats with a 10-12" round pedestal base to be attached with #10 screws directly thru the gelcoat into the plywood, with no backer... 8 to 10 screws is the usual number used.

a smaller pedestal base, or a tall pedestal will need more strength to hold it, so either more screws, or bolts with a backer...

and I would never use nut-serts on a boat.... its a bad idea because a bit of corrosion or salt intrusion into the threads, and if the bolts ever need to be removed, the inserts will spin and make a mess of it all... screws or thru bolts only...

[scubadiver535]

Thanks for the heads up. I was considering 5200 also.

[Centerline2]

Any feed back will be appreciated.

5200 shouldnt be used. it cant be trusted to hold the pedestal base by itself (nor should it be expected to), and if you ever need to remove the base, the 5200 will be a real problem. 4000 will offer everything desired in that application.,

[Mr._Darcy]

Without knowing for a certainty what the core is this is a difficult question to answer. Centerline2 suggest it may be plywood. Many of the larger Bayliners in the motor yacht series used 1.5 inch balsa core for the flybridge deck. It is found in the 32xx, and 38xx that I know of. Not sure what other Baylinr motor yachts use balsa core as well. The actual core used is critical to answering this question.

Greg

[Centerline2]

Without knowing for a certainty what the core is this is a difficult question to answer. Centerline2 suggest it may be plywood. Many of the larger Bayliners in the motor yacht series used 1.5 inch balsa core for the flybridge deck. It is found in the 32xx, and 38xx that I know of. Not sure what other Baylinr motor yachts use balsa core as well. The actual core used is critical to answering this question.

Greg

the glass layup in the area of that boat where a second helm seat pedistal would be attached, should be plenty thick enough to hold screws by itself... the thickness of the core should really only matter to the length of the screws.
but when the layup thickness is questionable, i pre drill the holes (to the proper size for the screws) and inject epoxy, and let it set for a few days before installing the screws. this gives the core a lot better holding power, integrated with the skin thickness... this method should work with any type of core material.

[Manzer74]

The captain wants a second helm seat facing forward on the upper helm. I know nothing about fiberglass but do have questions-
1- How thick is the flooring of the upper helm?
2- Pending the answer to #1, would anybody trust 3/8" nut certs to attach 3/4" plywood and the new pedestal?
OR
3- Do I need to remove the salon ceiling vinyl for thru hole backing?

Some vessels have raised plywood (double helm pic) but I can't tell if the plywood is thru hole with backing.
Some vessels have no plywood (twin seats pic) with pedestal only; also can't tell if thru hole backing.

Any feed back will be appreciated.

the photo facing the helm is the boat we bought last year. my daughter loves the second helm chair.

[Manzer74]

has anyone found replacement covers for the original helm chair?

[scubadiver535]

affordableboatcushions.com

[mmichellich]

Do you know for sure a 97 39 footer has wood in celing. I thought they used foam core by then. My sons new to him 28 foot 97 has foam core in all decks per Bayliner spec sheet.

[scubadiver3988]

I drilled a test hole and wood came out.

[noah2858]

For replacement upholstery for all things Bayliner Canvas Plus in Arlington Washington They own the patterns and can make most of the upholstery in a Bayliner by just having your hull number. I just had all of the fly bridge skins that included the captains chair and the downstairs dinette shipped to me in Florida for my 2000 3988. They fit perfect. 360-435-0932 Kim is the owner.

[Manzer74]

i called and spoke with her thank you.

[green650]

[ALASKAN_ADVENTURER]

the floor of the flybridge should be layed up with either 5/8 or 3/4 plywood as the core. depending on the footprint of the seat pedestal, a backer may not be needed.... its common for helm seats with a 10-12" round pedestal base to be attached with #10 screws directly thru the gelcoat into the plywood, with no backer... 8 to 10 screws is the usual number used.

a smaller pedestal base, or a tall pedestal will need more strength to hold it, so either more screws, or bolts with a backer...

and I would never use nut-serts on a boat.... its a bad idea because a bit of corrosion or salt intrusion into the threads, and if the bolts ever need to be removed, the inserts will spin and make a mess of it all... screws or thru bolts only...

These bigger boats have balsa core flybridge floors, you can NOT JUST SCREW A SEAT BASE DOWN, There is not plywood under the glass

[mmichellich]

Why do say these boats have balsa in them. Last big boats with balsa was the 45 and first few 47s in 1994s. Then to foam core.

[ALASKAN_ADVENTURER]

My mistake SORRY, every old Bayliner I been on is foam core on the flybridge sole, 32xx 38xx 45xx never been on a newer one