cross-grain dowels?

[Paul Silverman]

I'm about to resume refastening my boat, the Kelpie, a small English Channel pilot cutter designed by Bill Garden and built in 1942. I've been pulling square iron nails, inserting store-bought dowels and epoxy in the old holes,then later redrilling and using bronze screws that I cover w cedar plugs(cedar planks on oak frames). The dowels are just hardware store stock, typically 1/16 or 1/8 diameter. I'm thinking it would be better to use cross-grain (side-grain?) dowels, perhaps oak, for better holding power. What do you think? And does anyone know of a source for such doweling?

[Paul Silverman]

I'm about to resume refastening my boat, the Kelpie, a small English Channel pilot cutter designed by Bill Garden and built in 1942. I've been pulling square iron nails, inserting store-bought dowels and epoxy in the old holes,then later redrilling and using bronze screws that I cover w cedar plugs(cedar planks on oak frames). The dowels are just hardware store stock, typically 1/16 or 1/8 diameter. I'm thinking it would be better to use cross-grain (side-grain?) dowels, perhaps oak, for better holding power. What do you think? And does anyone know of a source for such doweling?

[Paul Silverman]

I'm about to resume refastening my boat, the Kelpie, a small English Channel pilot cutter designed by Bill Garden and built in 1942. I've been pulling square iron nails, inserting store-bought dowels and epoxy in the old holes,then later redrilling and using bronze screws that I cover w cedar plugs(cedar planks on oak frames). The dowels are just hardware store stock, typically 1/16 or 1/8 diameter. I'm thinking it would be better to use cross-grain (side-grain?) dowels, perhaps oak, for better holding power. What do you think? And does anyone know of a source for such doweling?

[JimConlin]

For back-filling abused screw holes, i've had OK luck with epoxy-microballoon putty of a mayonnaise consistency. It develops a good bond with the sides of the hole, it is about as crushable as the original wood material, so it'll embrace screw threads, and it can be administered with a syringe to the very bottom of the hole.

[JimConlin]

For back-filling abused screw holes, i've had OK luck with epoxy-microballoon putty of a mayonnaise consistency. It develops a good bond with the sides of the hole, it is about as crushable as the original wood material, so it'll embrace screw threads, and it can be administered with a syringe to the very bottom of the hole.

[JimConlin]

For back-filling abused screw holes, i've had OK luck with epoxy-microballoon putty of a mayonnaise consistency. It develops a good bond with the sides of the hole, it is about as crushable as the original wood material, so it'll embrace screw threads, and it can be administered with a syringe to the very bottom of the hole.

[Mrleft8]

Try Bamboo shish-ka-bab skewers. The fiberous nature of Bamboo will counteract any grab issues you might be afraid of.

[Mrleft8]

Try Bamboo shish-ka-bab skewers. The fiberous nature of Bamboo will counteract any grab issues you might be afraid of.

[Mrleft8]

Try Bamboo shish-ka-bab skewers. The fiberous nature of Bamboo will counteract any grab issues you might be afraid of.

[Gerald]

Look in your Harbor Freight catalog. They sell a set of plug cutters for a few dollars. The cutters cut a tapered plug or a straight plug. You can then cut any grain in any wood.
Gerald

[Gerald]

Look in your Harbor Freight catalog. They sell a set of plug cutters for a few dollars. The cutters cut a tapered plug or a straight plug. You can then cut any grain in any wood.
Gerald

[Gerald]

Look in your Harbor Freight catalog. They sell a set of plug cutters for a few dollars. The cutters cut a tapered plug or a straight plug. You can then cut any grain in any wood.
Gerald

[Ian McColgin]

Bungs are cross grain. They serve no structural purpose but are there to hide and protect the fastening head.

Structural dowls or trenails (I often misspell as trunnells) run with the grain. I've been happily replacing nasty fastenings with trenails in a variety of older boats for some years now with no problem.

I do not use blind wedges or outside wedges. I make them from black locust. Square to a bit over finished diameter, lay a shallow kerf down the middle of one face (more on this to come), whack the corners with a plane and then bang is through a hole in an iron plate to round it.

I make the trenail just a bit snug so to start it I have to gently sand/taper the inside. I put a bit of unthickened epoxy on the trenail both to lube the trenail on the way in and to seal the plank's end grain in the hole. I suppose the cured epoxy helps hold it in place but I really think the tight fit does all that. The kerf-groove is to allow exess epoxy to escape and allow the trenail to bottom out at the end of the hold. Sometimes I have a small exit hole on the inside of the frame as well but the kerf-groove is still good.

Why fill with wood and then screw when a good trenail will do even better?

The rule of thumb for trenail size is 1" or so diameter for every 100" of boat length. That has my schooner using 1/2" trenails. I think as the boat gets smaller, the porportion of trenail diameter needs to get a bit higher.

If you really want to replace with screws, then very long bungs will do well and be easier to drill out. You need to be looking very carefully at what's going on in the frame and how good a grip you'll get. Done rightly, epoxied in bungs through plank and into the frame and then bored and screwed will work. Allign those bungs' grain with the frame, not the plank.

G'luck

[ 03-07-2005, 08:05 AM: Message edited by: Ian McColgin ]

[Ian McColgin]

Bungs are cross grain. They serve no structural purpose but are there to hide and protect the fastening head.

Structural dowls or trenails (I often misspell as trunnells) run with the grain. I've been happily replacing nasty fastenings with trenails in a variety of older boats for some years now with no problem.

I do not use blind wedges or outside wedges. I make them from black locust. Square to a bit over finished diameter, lay a shallow kerf down the middle of one face (more on this to come), whack the corners with a plane and then bang is through a hole in an iron plate to round it.

I make the trenail just a bit snug so to start it I have to gently sand/taper the inside. I put a bit of unthickened epoxy on the trenail both to lube the trenail on the way in and to seal the plank's end grain in the hole. I suppose the cured epoxy helps hold it in place but I really think the tight fit does all that. The kerf-groove is to allow exess epoxy to escape and allow the trenail to bottom out at the end of the hold. Sometimes I have a small exit hole on the inside of the frame as well but the kerf-groove is still good.

Why fill with wood and then screw when a good trenail will do even better?

The rule of thumb for trenail size is 1" or so diameter for every 100" of boat length. That has my schooner using 1/2" trenails. I think as the boat gets smaller, the porportion of trenail diameter needs to get a bit higher.

If you really want to replace with screws, then very long bungs will do well and be easier to drill out. You need to be looking very carefully at what's going on in the frame and how good a grip you'll get. Done rightly, epoxied in bungs through plank and into the frame and then bored and screwed will work. Allign those bungs' grain with the frame, not the plank.

G'luck

[ 03-07-2005, 08:05 AM: Message edited by: Ian McColgin ]

[Ian McColgin]

Bungs are cross grain. They serve no structural purpose but are there to hide and protect the fastening head.

Structural dowls or trenails (I often misspell as trunnells) run with the grain. I've been happily replacing nasty fastenings with trenails in a variety of older boats for some years now with no problem.

I do not use blind wedges or outside wedges. I make them from black locust. Square to a bit over finished diameter, lay a shallow kerf down the middle of one face (more on this to come), whack the corners with a plane and then bang is through a hole in an iron plate to round it.

I make the trenail just a bit snug so to start it I have to gently sand/taper the inside. I put a bit of unthickened epoxy on the trenail both to lube the trenail on the way in and to seal the plank's end grain in the hole. I suppose the cured epoxy helps hold it in place but I really think the tight fit does all that. The kerf-groove is to allow exess epoxy to escape and allow the trenail to bottom out at the end of the hold. Sometimes I have a small exit hole on the inside of the frame as well but the kerf-groove is still good.

Why fill with wood and then screw when a good trenail will do even better?

The rule of thumb for trenail size is 1" or so diameter for every 100" of boat length. That has my schooner using 1/2" trenails. I think as the boat gets smaller, the porportion of trenail diameter needs to get a bit higher.

If you really want to replace with screws, then very long bungs will do well and be easier to drill out. You need to be looking very carefully at what's going on in the frame and how good a grip you'll get. Done rightly, epoxied in bungs through plank and into the frame and then bored and screwed will work. Allign those bungs' grain with the frame, not the plank.

G'luck

[ 03-07-2005, 08:05 AM: Message edited by: Ian McColgin ]

[Paul Silverman]

Thanks, all, for your help. I'm reluctant to use plugs instead of dowels for 2 reasons: I don't think that I can cut plugs that are long enough (about 2 to 2 1/2 inches; I would need to enlarge the nail hole by drilling it and am likely to miss the original nail track which would leave a void. Trennels are tempting particularly since they have a long history, but sound extremely labor intensive- I have many thousands of nails to pull and replace. I may try using the epoxy/syringe suggestion. I already have been injecting thin epoxy into the empty nail holes, then inserting narrow diameter dowels dipped in epoxy, breaking off the dowels slightly below the planking surface, and troweling in thickened epoxy to fill as much of the remaining void as possible. I mark the exact position of the old hole and when the epoxy has cured drill with a fuller bit in the same place (unless the nail had broken off)for a screw. Among the many difficulties in this process is that the syringes clog very easily with any detreous in the epoxy. The epoxy becomes contaminated by bits of wood stuck to the outside of the syringe as I repeatedly fill the syringe. I'm concerned that if I thicken the epoxy to be used in the syringe (as was suggested) that I this will become even more of a problem....

[Paul Silverman]

Thanks, all, for your help. I'm reluctant to use plugs instead of dowels for 2 reasons: I don't think that I can cut plugs that are long enough (about 2 to 2 1/2 inches; I would need to enlarge the nail hole by drilling it and am likely to miss the original nail track which would leave a void. Trennels are tempting particularly since they have a long history, but sound extremely labor intensive- I have many thousands of nails to pull and replace. I may try using the epoxy/syringe suggestion. I already have been injecting thin epoxy into the empty nail holes, then inserting narrow diameter dowels dipped in epoxy, breaking off the dowels slightly below the planking surface, and troweling in thickened epoxy to fill as much of the remaining void as possible. I mark the exact position of the old hole and when the epoxy has cured drill with a fuller bit in the same place (unless the nail had broken off)for a screw. Among the many difficulties in this process is that the syringes clog very easily with any detreous in the epoxy. The epoxy becomes contaminated by bits of wood stuck to the outside of the syringe as I repeatedly fill the syringe. I'm concerned that if I thicken the epoxy to be used in the syringe (as was suggested) that I this will become even more of a problem....

[Paul Silverman]

Thanks, all, for your help. I'm reluctant to use plugs instead of dowels for 2 reasons: I don't think that I can cut plugs that are long enough (about 2 to 2 1/2 inches; I would need to enlarge the nail hole by drilling it and am likely to miss the original nail track which would leave a void. Trennels are tempting particularly since they have a long history, but sound extremely labor intensive- I have many thousands of nails to pull and replace. I may try using the epoxy/syringe suggestion. I already have been injecting thin epoxy into the empty nail holes, then inserting narrow diameter dowels dipped in epoxy, breaking off the dowels slightly below the planking surface, and troweling in thickened epoxy to fill as much of the remaining void as possible. I mark the exact position of the old hole and when the epoxy has cured drill with a fuller bit in the same place (unless the nail had broken off)for a screw. Among the many difficulties in this process is that the syringes clog very easily with any detreous in the epoxy. The epoxy becomes contaminated by bits of wood stuck to the outside of the syringe as I repeatedly fill the syringe. I'm concerned that if I thicken the epoxy to be used in the syringe (as was suggested) that I this will become even more of a problem....

[Paul Silverman]

By the way, has anyone actually used bamboo skewers to fill then redrill holes? It sounds tempting, but I do wonder about such things as rot resistance and actual holding power.

[Paul Silverman]

By the way, has anyone actually used bamboo skewers to fill then redrill holes? It sounds tempting, but I do wonder about such things as rot resistance and actual holding power.

[Paul Silverman]

By the way, has anyone actually used bamboo skewers to fill then redrill holes? It sounds tempting, but I do wonder about such things as rot resistance and actual holding power.

[Ian McColgin]

The labor of trenails is in aquisition. You can solve that by making friends with whoever nearby makes dowls and get out a bunch in black locust or what ever other suitable wood you can get locally. Probably do this all cheaper than going to the hardware store for all sorts of dowls of unknown species.

The groove is nice but if you're at all careful with the epoxy you can get away without it.

On jobs I've done, the damage of wasting fastenings is great enough that going up to a half inch hole is good anyway.

If you use bungs and then rescrew, there is nothing at all wrong with epoxying in two or three bungs one on top of the other.

But I still think trenails are the way to go. Remember, you're doing the drilling and banging already, but saving all that second drilling, screwing and bunging.

Different boats, different longsplices.

G'luck.

[Ian McColgin]

The labor of trenails is in aquisition. You can solve that by making friends with whoever nearby makes dowls and get out a bunch in black locust or what ever other suitable wood you can get locally. Probably do this all cheaper than going to the hardware store for all sorts of dowls of unknown species.

The groove is nice but if you're at all careful with the epoxy you can get away without it.

On jobs I've done, the damage of wasting fastenings is great enough that going up to a half inch hole is good anyway.

If you use bungs and then rescrew, there is nothing at all wrong with epoxying in two or three bungs one on top of the other.

But I still think trenails are the way to go. Remember, you're doing the drilling and banging already, but saving all that second drilling, screwing and bunging.

Different boats, different longsplices.

G'luck.

[Ian McColgin]

The labor of trenails is in aquisition. You can solve that by making friends with whoever nearby makes dowls and get out a bunch in black locust or what ever other suitable wood you can get locally. Probably do this all cheaper than going to the hardware store for all sorts of dowls of unknown species.

The groove is nice but if you're at all careful with the epoxy you can get away without it.

On jobs I've done, the damage of wasting fastenings is great enough that going up to a half inch hole is good anyway.

If you use bungs and then rescrew, there is nothing at all wrong with epoxying in two or three bungs one on top of the other.

But I still think trenails are the way to go. Remember, you're doing the drilling and banging already, but saving all that second drilling, screwing and bunging.

Different boats, different longsplices.

G'luck.