jhughes
Well-Known Member
You don't say what kind of waterproof glue?
To any chippies out there - are biscuits strong enough?
- Thread starter Roach1948
- Start date
dbewick
Member
Biscuits are plenty strong enough for many things. If you use a "wet" glue, they expand to grip the inside of the slot. A double biscuit joint has similar strength to a mortice and tenon joint and furniture makers often use them even in "quality" pieces. That said, I probably would not want to use them in yacht joinery if it was possible to make a "proper" joint.
skipperscouse
Well-Known Member
if you are set on using biscuits , then make your own from more suitable timber, you surely don't need that many ?
also you can use epoxy in the winter , you just need a little local warmth until glue sets. baltocan or similar may be better though.
also you can use epoxy in the winter , you just need a little local warmth until glue sets. baltocan or similar may be better though.
Seanick
Well-Known Member
I presume you are making two panelled frameworks for each bunk. If your panels are not too large they will help support the frame, or add extra supports from the hull to the frame.
For this job one usually has a cleat on each bulkhead, a top support which also doubles as a shelf behind the backrest, and the bottom of the frame has one mid support. As to making these in the boat, one usually makes a full size patten from 4" strips of MDF, spliles the fore and aft bulkheads, then one dissapears into the warmth of the workshop, only to emerge again with the finished product. This space behind is also very usefull storage...
As to biscuits being strong enough.....I was taught that all interior joinery should take the weight of a falling man. How would Dallimore or Cooke want it ?
There is no job for PVA on any boat. Stick with polys (excuse the pun)
ps, Iolanthe, one of Cookes boats, is alive and well!
For this job one usually has a cleat on each bulkhead, a top support which also doubles as a shelf behind the backrest, and the bottom of the frame has one mid support. As to making these in the boat, one usually makes a full size patten from 4" strips of MDF, spliles the fore and aft bulkheads, then one dissapears into the warmth of the workshop, only to emerge again with the finished product. This space behind is also very usefull storage...
As to biscuits being strong enough.....I was taught that all interior joinery should take the weight of a falling man. How would Dallimore or Cooke want it ?
There is no job for PVA on any boat. Stick with polys (excuse the pun)
ps, Iolanthe, one of Cookes boats, is alive and well!
Roach1948
Well-Known Member
Well actually the design shows one large opening panel - maybe I should not be such a purist. Two panels per side make sense.
The shelf you describe is in the design and I am sure it will be very useful for storage. I have adapted the design to make the top mahog plank protrude 6" from the shelf. The it can then act as a fiddle for books and double as a hand-hold.
One thing I am not clear about is what you mean by a "cleat" -is this like a mini hanging-knee that will support the panels or back-support against the hull?
The shelf you describe is in the design and I am sure it will be very useful for storage. I have adapted the design to make the top mahog plank protrude 6" from the shelf. The it can then act as a fiddle for books and double as a hand-hold.
One thing I am not clear about is what you mean by a "cleat" -is this like a mini hanging-knee that will support the panels or back-support against the hull?
fisherman
Well-Known Member
Do what's often done on site: build up back supports with layers of MDF and gripfill, cut out a bit of ply, roughly, screw it on and fill all round.
"Bit of putty, bit of paint, makes a chippy what he aint."
"Bit of putty, bit of paint, makes a chippy what he aint."
Seanick
Well-Known Member
Sorry, a cleat is just like a batten, fastened to a bulkhead to support a shelf, or in the corner of a ply box to join the edges. I was taught the term at college, and its stuck! (well, with a few screws as well, just in case!).
Roach1948
Well-Known Member
Thanks everybody I have learnt LOADS on this thread - as I know some of you really are chippies and/or boatbuilders I am apprehensive about posting a pic of my handiwork - but depending on how well the job is done, I will consider it!