RE: [bolger] Fasteners in butt blocks
On Mon, 4 Jun 2001, Jim Chamberlin RCSIS wrote:
column", but in shear strength. If you want such an effect, a ring nail
is cheaper, easier, and more effective.
The holes may get bubbles in them, and assuring no bubbles and a smooth
surface will be much more work than pounding in a copper or brass nail.
> Has anyone thought of just drilling a series of holes through theThis strikes me as a weak idea. Epoxy's strength is not as a "tension
> panels and the butt blocks and allowing the holes to fill with epoxy
> during the gluing process? The epoxy filled holes are easy sanding,
> no puttying required and saves on hardware. An epoxy rivited,
> fiberglass reinforced, butt joint. Its too late and I'm going to bed.
column", but in shear strength. If you want such an effect, a ring nail
is cheaper, easier, and more effective.
The holes may get bubbles in them, and assuring no bubbles and a smooth
surface will be much more work than pounding in a copper or brass nail.
6/4/01 11:09:44 PM, "Jim Chamberlin RCSIS" <jchamberlin@...> wrote:
such ideas. His current solution is similar to what you suggest, but involves a tight bundle of epoxy saturated 'glass, quote:
"I was skeptical when Robb sent WoodenBoat a manuscript last year entitled 'The Instant End Grain Fastener.' It was a procedure for fastening plank ends
to a transom, and it involved drilling a hole, in the ususal manner, through the plank and into the transom's edge. But instead of driving a fastening (sic) into the hole,
Robb heats the hole with a hot bronze rod, ingects it with epoxy, and then stuffs it with fiberglass threads, followed by more epoxy. Again, the pumping action of the
wood cells draws the thin epoxy into the voids.
I began to tell Robb my concerns about that technique when I visited him last winter. he was the only one doing it, I started to explain. What are the
pitfalls..? Shouldn't we test it more...? A less-experienced builder might get into troub... He smiled and reached for the cieling of the shop before I could finish, saying,
'We ain't doing that way anymore; we found a better way.' He took from the overhead a thin, 2' untapered stalactite of fiberglass and epoxy that was hanging from a
wire: The new and improved end-grain and plank-lap fastening, easier to drive into the hole. It works for laps in a manner similar to the plank-to-transom technique:
drill hole, heat, and voila`! An ingenious fiberglass rivet-- and planetarium show, compliments of so many translucent fastenings-cum-stars twinkling against a sky of
tulip poplar planking."
The hot bronze rod is also of interest... Robb likes to turn the tables on the outgassing problem (epoxy exotherm heat will often cause gasses within wood to expand
and create bubbles in the epoxy). He figures if expanding gasses can blow bubbles, they can also suck epoxy, so he heats the wood before applying epoxy then
allows the whole arrangement to cool while the epoxy cures. I am sure it requires very slow cure epoxy.
I am probably pushing the limits of fair use here so I will stop. Those of you who don't subscribe to WoodenBoat might want to take a look at the article, it is in the
May/June '01 issue.
Pax,
Chris B
>...Has anyone thought of just drilling a seriesThe most recent WoodenBoat magazine had an article by Matthew P. Murphy on Georgia boatbuilder Robb White. He apparently has experimented extensively with
>of holes through the panels and the butt blocks and allowing the holes to
>fill with epoxy during the gluing process? The epoxy filled holes are easy
>sanding, no puttying required and saves on hardware. An epoxy rivited,
>fiberglass reinforced, butt joint. Its too late and I'm going to bed.
>
>Jim C
such ideas. His current solution is similar to what you suggest, but involves a tight bundle of epoxy saturated 'glass, quote:
"I was skeptical when Robb sent WoodenBoat a manuscript last year entitled 'The Instant End Grain Fastener.' It was a procedure for fastening plank ends
to a transom, and it involved drilling a hole, in the ususal manner, through the plank and into the transom's edge. But instead of driving a fastening (sic) into the hole,
Robb heats the hole with a hot bronze rod, ingects it with epoxy, and then stuffs it with fiberglass threads, followed by more epoxy. Again, the pumping action of the
wood cells draws the thin epoxy into the voids.
I began to tell Robb my concerns about that technique when I visited him last winter. he was the only one doing it, I started to explain. What are the
pitfalls..? Shouldn't we test it more...? A less-experienced builder might get into troub... He smiled and reached for the cieling of the shop before I could finish, saying,
'We ain't doing that way anymore; we found a better way.' He took from the overhead a thin, 2' untapered stalactite of fiberglass and epoxy that was hanging from a
wire: The new and improved end-grain and plank-lap fastening, easier to drive into the hole. It works for laps in a manner similar to the plank-to-transom technique:
drill hole, heat, and voila`! An ingenious fiberglass rivet-- and planetarium show, compliments of so many translucent fastenings-cum-stars twinkling against a sky of
tulip poplar planking."
The hot bronze rod is also of interest... Robb likes to turn the tables on the outgassing problem (epoxy exotherm heat will often cause gasses within wood to expand
and create bubbles in the epoxy). He figures if expanding gasses can blow bubbles, they can also suck epoxy, so he heats the wood before applying epoxy then
allows the whole arrangement to cool while the epoxy cures. I am sure it requires very slow cure epoxy.
I am probably pushing the limits of fair use here so I will stop. Those of you who don't subscribe to WoodenBoat might want to take a look at the article, it is in the
May/June '01 issue.
Pax,
Chris B
I have to second Jamie's idea. I know intellectually that the butt block
joint will hold, but in two Pointy Skiffs, I used screws or ring nails in
the butt blocks with 3" fiberglass tape epoxied on the outside. On the next
project that calls for butt blocks, I'm not using mechanical
fasteners...........(I think). Has anyone thought of just drilling a series
of holes through the panels and the butt blocks and allowing the holes to
fill with epoxy during the gluing process? The epoxy filled holes are easy
sanding, no puttying required and saves on hardware. An epoxy rivited,
fiberglass reinforced, butt joint. Its too late and I'm going to bed.
Jim C
joint will hold, but in two Pointy Skiffs, I used screws or ring nails in
the butt blocks with 3" fiberglass tape epoxied on the outside. On the next
project that calls for butt blocks, I'm not using mechanical
fasteners...........(I think). Has anyone thought of just drilling a series
of holes through the panels and the butt blocks and allowing the holes to
fill with epoxy during the gluing process? The epoxy filled holes are easy
sanding, no puttying required and saves on hardware. An epoxy rivited,
fiberglass reinforced, butt joint. Its too late and I'm going to bed.
Jim C
> -----Original Message-----
> From: Orr, Jamie [mailto:jorr@...]
> Sent: Monday, June 04, 2001 7:39 AM
> To: 'bolger@yahoogroups.com'
> Subject: RE: [bolger] Fasteners in butt blocks
>
>
> I like the added peace of mind I get with mechanical fasteners,
> in addition
> to glue -- I used 1" bronze screws in the butt blocks in my Chebacco (1/2
> inch ply) and left them in. Gluing only joins top layer of veneer on each
> piece, but the screws pass on some of the load to the other veneers in the
> plywood. With these, and a layer of glass on the outside, I don't worry
> about the joints when I'm out on the water.
>
> Besides, screws hold the joint in alignment and provide clamping pressure
> while the glue dries, which will help give you a fair joint. If
> the points
> stick out, the bronze tips are easily ground off.
>
> Jamie Orr
>
> -----Original Message-----
> From: Giuseppe 'Pippo' Bianco [mailto:giuseppe.bianco@...]
> Sent: Monday, June 04, 2001 3:45 AM
> To:bolger@yahoogroups.com
> Subject: [bolger] Fasteners in butt blocks
>
>
> Dear all, does it make any sense to use fasteners in plywood butt
> blocks (glued with epoxy)? It seems to me that the added strenght of
> a few nails or screws is really marginal as compared with the epoxy
> bond. Any thoughts?
>
>
> Bolger rules!!!
> - no cursing, flaming, trolling, or spamming
> - no flogging dead horses
> - add something: take "thanks!" and "ditto!" posts off-list.
> - stay on topic and punctuate
> - add your comments at the TOP and SIGN your posts
> - To order plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA,
> 01930, Fax: (978) 282-1349
>
>
> Your use of Yahoo! Groups is subject tohttp://docs.yahoo.com/info/terms/
>
>
> Bolger rules!!!
> - no cursing, flaming, trolling, or spamming
> - no flogging dead horses
> - add something: take "thanks!" and "ditto!" posts off-list.
> - stay on topic and punctuate
> - add your comments at the TOP and SIGN your posts
> - To order plans: Mr. Philip C. Bolger, P.O. Box 1209,
> Gloucester, MA, 01930, Fax: (978) 282-1349
>
>
> Your use of Yahoo! Groups is subject tohttp://docs.yahoo.com/info/terms/
>
>
I like the added peace of mind I get with mechanical fasteners, in addition
to glue -- I used 1" bronze screws in the butt blocks in my Chebacco (1/2
inch ply) and left them in. Gluing only joins top layer of veneer on each
piece, but the screws pass on some of the load to the other veneers in the
plywood. With these, and a layer of glass on the outside, I don't worry
about the joints when I'm out on the water.
Besides, screws hold the joint in alignment and provide clamping pressure
while the glue dries, which will help give you a fair joint. If the points
stick out, the bronze tips are easily ground off.
Jamie Orr
-----Original Message-----
From: Giuseppe 'Pippo' Bianco [mailto:giuseppe.bianco@...]
Sent: Monday, June 04, 2001 3:45 AM
To:bolger@yahoogroups.com
Subject: [bolger] Fasteners in butt blocks
Dear all, does it make any sense to use fasteners in plywood butt
blocks (glued with epoxy)? It seems to me that the added strenght of
a few nails or screws is really marginal as compared with the epoxy
bond. Any thoughts?
Bolger rules!!!
- no cursing, flaming, trolling, or spamming
- no flogging dead horses
- add something: take "thanks!" and "ditto!" posts off-list.
- stay on topic and punctuate
- add your comments at the TOP and SIGN your posts
- To order plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA,
01930, Fax: (978) 282-1349
Your use of Yahoo! Groups is subject tohttp://docs.yahoo.com/info/terms/
to glue -- I used 1" bronze screws in the butt blocks in my Chebacco (1/2
inch ply) and left them in. Gluing only joins top layer of veneer on each
piece, but the screws pass on some of the load to the other veneers in the
plywood. With these, and a layer of glass on the outside, I don't worry
about the joints when I'm out on the water.
Besides, screws hold the joint in alignment and provide clamping pressure
while the glue dries, which will help give you a fair joint. If the points
stick out, the bronze tips are easily ground off.
Jamie Orr
-----Original Message-----
From: Giuseppe 'Pippo' Bianco [mailto:giuseppe.bianco@...]
Sent: Monday, June 04, 2001 3:45 AM
To:bolger@yahoogroups.com
Subject: [bolger] Fasteners in butt blocks
Dear all, does it make any sense to use fasteners in plywood butt
blocks (glued with epoxy)? It seems to me that the added strenght of
a few nails or screws is really marginal as compared with the epoxy
bond. Any thoughts?
Bolger rules!!!
- no cursing, flaming, trolling, or spamming
- no flogging dead horses
- add something: take "thanks!" and "ditto!" posts off-list.
- stay on topic and punctuate
- add your comments at the TOP and SIGN your posts
- To order plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA,
01930, Fax: (978) 282-1349
Your use of Yahoo! Groups is subject tohttp://docs.yahoo.com/info/terms/
I've used a belt and suspenders approach. I use copper roofing nails
clinched over to hold the plywood butt block. Then I tape over the
outside ofthe seem with two layers of tape. The nails are needed
only to hold thebutwhile theepoxy sets. I leave them in out of
laziness.
Regards
Andy Farquhar
clinched over to hold the plywood butt block. Then I tape over the
outside ofthe seem with two layers of tape. The nails are needed
only to hold thebutwhile theepoxy sets. I leave them in out of
laziness.
Regards
Andy Farquhar
Pippo:
I have actual experience with this subject. When I built my Tennessee, I
used the recommended ply butt blocks on the sides. I used temporary screws
during the curing time, and later filled the holes. Everything looked fine
until about a year after the boat was finished. At that time, cracks
started to open up, requiring me to go back and tape the outsides of the
joints. Of course, this meant that I had to do a lot of sanding, fairing
and repainting which would have been much easier to do in the first place.
Since then, I have always used taped joints - they are easy, and they work.
Chuck
I have actual experience with this subject. When I built my Tennessee, I
used the recommended ply butt blocks on the sides. I used temporary screws
during the curing time, and later filled the holes. Everything looked fine
until about a year after the boat was finished. At that time, cracks
started to open up, requiring me to go back and tape the outsides of the
joints. Of course, this meant that I had to do a lot of sanding, fairing
and repainting which would have been much easier to do in the first place.
Since then, I have always used taped joints - they are easy, and they work.
Chuck
>
> Dear all, does it make any sense to use fasteners in plywood butt
> blocks (glued with epoxy)? It seems to me that the added strenght of
> a few nails or screws is really marginal as compared with the epoxy
> bond. Any thoughts?
>
>
Not required, except perhaps to initially hold the separate pieces
together while the epoxy cures.
Does this mean you're still building Micro?
Cheers,
randy
building away in boston
--- In bolger@y..., "Giuseppe 'Pippo' Bianco" <giuseppe.bianco@a...>
wrote:
together while the epoxy cures.
Does this mean you're still building Micro?
Cheers,
randy
building away in boston
--- In bolger@y..., "Giuseppe 'Pippo' Bianco" <giuseppe.bianco@a...>
wrote:
> Dear all, does it make any sense to use fasteners in plywood buttof
> blocks (glued with epoxy)? It seems to me that the added strenght
> a few nails or screws is really marginal as compared with the epoxy
> bond. Any thoughts?
Dear all, does it make any sense to use fasteners in plywood butt
blocks (glued with epoxy)? It seems to me that the added strenght of
a few nails or screws is really marginal as compared with the epoxy
bond. Any thoughts?
blocks (glued with epoxy)? It seems to me that the added strenght of
a few nails or screws is really marginal as compared with the epoxy
bond. Any thoughts?