Backing straps for steam bending

[Bruce Hooke]

Has anyone found a good source for thin (16 gauge and 1/16") steel bar/strap stock for use as the backing strap for steam bending? My local Home De(s)pot has 1/8" bar stock, which is fine for bending wood that is 1" thick and up, but the only stuff they have that is any thinner is perforated, which leaves a nice row of raised bumps on the wood! None of my other local hardware stores do any better. McMaster-Carr has some stuff that would work but it's a bit pricey because it is round edged, high-grade steel. My local steel merchants here in Rhode Island don't seem willing to do business with anyone who wants less than 500 pounds of steel...

[Bruce Hooke]

Has anyone found a good source for thin (16 gauge and 1/16") steel bar/strap stock for use as the backing strap for steam bending? My local Home De(s)pot has 1/8" bar stock, which is fine for bending wood that is 1" thick and up, but the only stuff they have that is any thinner is perforated, which leaves a nice row of raised bumps on the wood! None of my other local hardware stores do any better. McMaster-Carr has some stuff that would work but it's a bit pricey because it is round edged, high-grade steel. My local steel merchants here in Rhode Island don't seem willing to do business with anyone who wants less than 500 pounds of steel...

[Bruce Hooke]

Has anyone found a good source for thin (16 gauge and 1/16") steel bar/strap stock for use as the backing strap for steam bending? My local Home De(s)pot has 1/8" bar stock, which is fine for bending wood that is 1" thick and up, but the only stuff they have that is any thinner is perforated, which leaves a nice row of raised bumps on the wood! None of my other local hardware stores do any better. McMaster-Carr has some stuff that would work but it's a bit pricey because it is round edged, high-grade steel. My local steel merchants here in Rhode Island don't seem willing to do business with anyone who wants less than 500 pounds of steel...

[TomRobb]

Try a sheet metal shop. They can shear it out of sheet stock for you in most any length & width you might need. Isn't 1/16" overkill? Why so thick?

[TomRobb]

Try a sheet metal shop. They can shear it out of sheet stock for you in most any length & width you might need. Isn't 1/16" overkill? Why so thick?

[TomRobb]

Try a sheet metal shop. They can shear it out of sheet stock for you in most any length & width you might need. Isn't 1/16" overkill? Why so thick?

[Bruce Hooke]

TomRobb:
Thanks. That's a good idea. My thinking on the thickness is to use about the thickest steel that can make the bend without too much resistance, so as to reduce the tendancy of the steel to flex back away from the wood at the ends thus causing the end blocks to slip off or bend away from the wood stock...
- Bruce

[Bruce Hooke]

TomRobb:
Thanks. That's a good idea. My thinking on the thickness is to use about the thickest steel that can make the bend without too much resistance, so as to reduce the tendancy of the steel to flex back away from the wood at the ends thus causing the end blocks to slip off or bend away from the wood stock...
- Bruce

[Bruce Hooke]

TomRobb:
Thanks. That's a good idea. My thinking on the thickness is to use about the thickest steel that can make the bend without too much resistance, so as to reduce the tendancy of the steel to flex back away from the wood at the ends thus causing the end blocks to slip off or bend away from the wood stock...
- Bruce

[Ron Williamson]

Bruce
You might try the scrap/recycling bin at that Homely Despot.
Lumber banding straps come in a few widths/gauges(though nothing approaching 1/16")and they are free.
Have fun
R

[Ron Williamson]

Bruce
You might try the scrap/recycling bin at that Homely Despot.
Lumber banding straps come in a few widths/gauges(though nothing approaching 1/16")and they are free.
Have fun
R

[Ron Williamson]

Bruce
You might try the scrap/recycling bin at that Homely Despot.
Lumber banding straps come in a few widths/gauges(though nothing approaching 1/16")and they are free.
Have fun
R

[TomRobb]

I've done a bit of steam bending but never used a compression strap. My impression was that the ends of the straps were clamped to the wood such that they couldn't possibly pull away. Is this a known problem?
You'll have enough to do getting it all clamped up before it cools too much without fighting a stiff hunk of steel too. It's all in tension. There's no beam stiffness needed. Or wanted, LOL.
Fine Woodworking magazine a web site wherein there's a lengthy explaination of the process.

[This message has been edited by TomRobb (edited 06-11-2001).]

[TomRobb]

I've done a bit of steam bending but never used a compression strap. My impression was that the ends of the straps were clamped to the wood such that they couldn't possibly pull away. Is this a known problem?
You'll have enough to do getting it all clamped up before it cools too much without fighting a stiff hunk of steel too. It's all in tension. There's no beam stiffness needed. Or wanted, LOL.
Fine Woodworking magazine a web site wherein there's a lengthy explaination of the process.

[This message has been edited by TomRobb (edited 06-11-2001).]

[TomRobb]

I've done a bit of steam bending but never used a compression strap. My impression was that the ends of the straps were clamped to the wood such that they couldn't possibly pull away. Is this a known problem?
You'll have enough to do getting it all clamped up before it cools too much without fighting a stiff hunk of steel too. It's all in tension. There's no beam stiffness needed. Or wanted, LOL.
Fine Woodworking magazine a web site wherein there's a lengthy explaination of the process.

[This message has been edited by TomRobb (edited 06-11-2001).]

[bob goeckel]

i had the same questions and just as i was doing my first bending i spotted my 4' aluminum ruler on the wall. it has worked great and can be bent back straight after use and doesn't rust.

[bob goeckel]

i had the same questions and just as i was doing my first bending i spotted my 4' aluminum ruler on the wall. it has worked great and can be bent back straight after use and doesn't rust.

[bob goeckel]

i had the same questions and just as i was doing my first bending i spotted my 4' aluminum ruler on the wall. it has worked great and can be bent back straight after use and doesn't rust.

[Bruce Hooke]

Thanks all...
I haven't done much steam bending with compression straps but when I have this is definitely a problem I have run into. However, it may have been because I was trying to avoid using clamps since the clamps got in the way of the bending form (which maybe means I should redesign my forms!). Just as background: all it takes is a small gap between the steel and the strap near the end blocks (which are attached to the steel) to put the end block at an angle to the wood and give the forces something to work on to make the end blocks slide further off the wood. Also, for what it's worth, the steel thickness I quoted came from Fine Woodworking...

[Bruce Hooke]

Thanks all...
I haven't done much steam bending with compression straps but when I have this is definitely a problem I have run into. However, it may have been because I was trying to avoid using clamps since the clamps got in the way of the bending form (which maybe means I should redesign my forms!). Just as background: all it takes is a small gap between the steel and the strap near the end blocks (which are attached to the steel) to put the end block at an angle to the wood and give the forces something to work on to make the end blocks slide further off the wood. Also, for what it's worth, the steel thickness I quoted came from Fine Woodworking...

[Bruce Hooke]

Thanks all...
I haven't done much steam bending with compression straps but when I have this is definitely a problem I have run into. However, it may have been because I was trying to avoid using clamps since the clamps got in the way of the bending form (which maybe means I should redesign my forms!). Just as background: all it takes is a small gap between the steel and the strap near the end blocks (which are attached to the steel) to put the end block at an angle to the wood and give the forces something to work on to make the end blocks slide further off the wood. Also, for what it's worth, the steel thickness I quoted came from Fine Woodworking...

[Keith Wilson]

Is there clearance to make the end blocks with a little hook or shelf (preferably at an angle so it wedges tight) to capture the piece that's being bent and prevent it from pulling away from the steel? (Sure would be easier to explain if I knew how to post a sketch) If so, you could use relatively thin metal, which has a lot of advantages.

[Keith Wilson]

Is there clearance to make the end blocks with a little hook or shelf (preferably at an angle so it wedges tight) to capture the piece that's being bent and prevent it from pulling away from the steel? (Sure would be easier to explain if I knew how to post a sketch) If so, you could use relatively thin metal, which has a lot of advantages.

[Keith Wilson]

Is there clearance to make the end blocks with a little hook or shelf (preferably at an angle so it wedges tight) to capture the piece that's being bent and prevent it from pulling away from the steel? (Sure would be easier to explain if I knew how to post a sketch) If so, you could use relatively thin metal, which has a lot of advantages.

[Bruce Hooke]

Well, I went back and took another look at the article and it looks like the author is clamping the strap to the stock near the end blocks...so now the (probably unanswerable) question is why does the author (William A. Keyser, Jr.) recommend such heavy steel?

[Bruce Hooke]

Well, I went back and took another look at the article and it looks like the author is clamping the strap to the stock near the end blocks...so now the (probably unanswerable) question is why does the author (William A. Keyser, Jr.) recommend such heavy steel?

[Bruce Hooke]

Well, I went back and took another look at the article and it looks like the author is clamping the strap to the stock near the end blocks...so now the (probably unanswerable) question is why does the author (William A. Keyser, Jr.) recommend such heavy steel?

[TomRobb]

Maybe it was what he had on hand.

[TomRobb]

Maybe it was what he had on hand.

[TomRobb]

Maybe it was what he had on hand.

[Bruce Hooke]

TomRobb: Good idea but in this case I don't think so because he runs down the list and says for this thickness of wood I use this thickness of steel and so for 3-4 different ranges, so its pretty clear he's talking about his 'standard practices'.

Keith: That's a good idea (if a little bit more complex to make for someone like me who isn't really set up for doing much metal work) so I will keep it in mind if other methods don't work. Thanks!

[This message has been edited by Bruce Hooke (edited 06-12-2001).]

[Bruce Hooke]

TomRobb: Good idea but in this case I don't think so because he runs down the list and says for this thickness of wood I use this thickness of steel and so for 3-4 different ranges, so its pretty clear he's talking about his 'standard practices'.

Keith: That's a good idea (if a little bit more complex to make for someone like me who isn't really set up for doing much metal work) so I will keep it in mind if other methods don't work. Thanks!

[This message has been edited by Bruce Hooke (edited 06-12-2001).]

[Bruce Hooke]

TomRobb: Good idea but in this case I don't think so because he runs down the list and says for this thickness of wood I use this thickness of steel and so for 3-4 different ranges, so its pretty clear he's talking about his 'standard practices'.

Keith: That's a good idea (if a little bit more complex to make for someone like me who isn't really set up for doing much metal work) so I will keep it in mind if other methods don't work. Thanks!

[This message has been edited by Bruce Hooke (edited 06-12-2001).]

[Mike DeHart]

I inherited a pile of rib bending backing straps along with a skiff. They are just galvanized sheet metal, the same stuff that an HVAC company bends into ductwork. The strips are about 1-1/2 inches wide by 5 or 6 feet long. The thickness is not much. I will guess about .030" since I don't have one here to measure. They are quite flexible. One end is bent up 90° and has a small hole punched through the center of the resulting square. I assume this was to tack it in place on the end of the rib, but I haven't tried it yet. These strips were used (if I remember correctly) by a local boatbuilder/repairman back when fishing skiffs were plentiful. It doesn't take a thick piece of steel to keep a piece of wood in compression as it bends. However, I can imagine a furniture builder using a thicker strip since a chair back would need to have an even, smooth, and symmetrical curve. A heavier strip would act as a fairing batten to even out the workpiece.

[Mike DeHart]

I inherited a pile of rib bending backing straps along with a skiff. They are just galvanized sheet metal, the same stuff that an HVAC company bends into ductwork. The strips are about 1-1/2 inches wide by 5 or 6 feet long. The thickness is not much. I will guess about .030" since I don't have one here to measure. They are quite flexible. One end is bent up 90° and has a small hole punched through the center of the resulting square. I assume this was to tack it in place on the end of the rib, but I haven't tried it yet. These strips were used (if I remember correctly) by a local boatbuilder/repairman back when fishing skiffs were plentiful. It doesn't take a thick piece of steel to keep a piece of wood in compression as it bends. However, I can imagine a furniture builder using a thicker strip since a chair back would need to have an even, smooth, and symmetrical curve. A heavier strip would act as a fairing batten to even out the workpiece.

[Mike DeHart]

I inherited a pile of rib bending backing straps along with a skiff. They are just galvanized sheet metal, the same stuff that an HVAC company bends into ductwork. The strips are about 1-1/2 inches wide by 5 or 6 feet long. The thickness is not much. I will guess about .030" since I don't have one here to measure. They are quite flexible. One end is bent up 90° and has a small hole punched through the center of the resulting square. I assume this was to tack it in place on the end of the rib, but I haven't tried it yet. These strips were used (if I remember correctly) by a local boatbuilder/repairman back when fishing skiffs were plentiful. It doesn't take a thick piece of steel to keep a piece of wood in compression as it bends. However, I can imagine a furniture builder using a thicker strip since a chair back would need to have an even, smooth, and symmetrical curve. A heavier strip would act as a fairing batten to even out the workpiece.

[TomRobb]

If you're steaming ribs,timbers, whatever into a clinker boat, the boat will fair the piece. If it's over the outside of the forms as in Herreshoff style construction, or over ribands the forms/ribands will fair the piece. I'm not sure where you'd need the strap. What are you bending?
Maybe he, Lon, uses a hefty strap because he likes the heft of the thing, or maybe the fastener is less likely to elongate the hole in the strap under sheer with the stout pieces he's bending? You'd have to ask him or maybe buy the video. It's only 11 or 12 bucks http://media5.hypernet.com/~dick/ubb/smile.gif

[TomRobb]

If you're steaming ribs,timbers, whatever into a clinker boat, the boat will fair the piece. If it's over the outside of the forms as in Herreshoff style construction, or over ribands the forms/ribands will fair the piece. I'm not sure where you'd need the strap. What are you bending?
Maybe he, Lon, uses a hefty strap because he likes the heft of the thing, or maybe the fastener is less likely to elongate the hole in the strap under sheer with the stout pieces he's bending? You'd have to ask him or maybe buy the video. It's only 11 or 12 bucks http://media5.hypernet.com/~dick/ubb/smile.gif

[TomRobb]

If you're steaming ribs,timbers, whatever into a clinker boat, the boat will fair the piece. If it's over the outside of the forms as in Herreshoff style construction, or over ribands the forms/ribands will fair the piece. I'm not sure where you'd need the strap. What are you bending?
Maybe he, Lon, uses a hefty strap because he likes the heft of the thing, or maybe the fastener is less likely to elongate the hole in the strap under sheer with the stout pieces he's bending? You'd have to ask him or maybe buy the video. It's only 11 or 12 bucks http://media5.hypernet.com/~dick/ubb/smile.gif

[Cecil Borel]

I wonder if it would be possible to modify used bandsaw blades for the purpose? Perhaps grinding the teeth dull, tackwelding, and attaching wooden handles would make them useful for this purpose. I wonder if anyone has used this approach?

[Cecil Borel]

I wonder if it would be possible to modify used bandsaw blades for the purpose? Perhaps grinding the teeth dull, tackwelding, and attaching wooden handles would make them useful for this purpose. I wonder if anyone has used this approach?

[Cecil Borel]

I wonder if it would be possible to modify used bandsaw blades for the purpose? Perhaps grinding the teeth dull, tackwelding, and attaching wooden handles would make them useful for this purpose. I wonder if anyone has used this approach?

[suedebriar]

I used metal straping bought from a metal fabrication shop. It is used for holding down loads on trucks and comes in widths up to about 1 1/2 inch.

[suedebriar]

I used metal straping bought from a metal fabrication shop. It is used for holding down loads on trucks and comes in widths up to about 1 1/2 inch.

[suedebriar]

I used metal straping bought from a metal fabrication shop. It is used for holding down loads on trucks and comes in widths up to about 1 1/2 inch.

[Bruce Hooke]

Thank you all!
Cecil Borel's idea sounds interesting for a shop that uses 1" wide (and up) bandsaw blades. I just have a 14" bandsaw so none of my blades are anywhere near wide enough for what I am doing (also my bandsaw is only a few months old so I all my blades still have lots of life left in them http://media5.hypernet.com/~dick/ubb/smile.gif). Also, I wonder how hard it is it to drill holes in a bandsaw blade? That is also my concern with using the 'truckers strapping'. How hard is it to drill holes in that stuff -- is it spring steel that needs to be tempered before you can drill holes for attaching the end blocks?.


So far the two best reasons I have heard for thicker steel are to keep the fasteners holding on the end blocks from elongating their holes (TomRobb) and to help keep the bend even and smooth (Mike DeHart). As TomRobb notes the latter issue would probably not apply for situations like bending into the inside of a hull since the hull would keep things even. On an outside bend (either over ribands or over a form) I have certainly run into situations where during the bend one part of the piece being bent wanted to bend too much. That is where heavier steel might help. In my case I am bending thwart knees so I will be making rather tight bends over a form...

[This message has been edited by Bruce Hooke (edited 06-15-2001).]

[Bruce Hooke]

Thank you all!
Cecil Borel's idea sounds interesting for a shop that uses 1" wide (and up) bandsaw blades. I just have a 14" bandsaw so none of my blades are anywhere near wide enough for what I am doing (also my bandsaw is only a few months old so I all my blades still have lots of life left in them http://media5.hypernet.com/~dick/ubb/smile.gif). Also, I wonder how hard it is it to drill holes in a bandsaw blade? That is also my concern with using the 'truckers strapping'. How hard is it to drill holes in that stuff -- is it spring steel that needs to be tempered before you can drill holes for attaching the end blocks?.


So far the two best reasons I have heard for thicker steel are to keep the fasteners holding on the end blocks from elongating their holes (TomRobb) and to help keep the bend even and smooth (Mike DeHart). As TomRobb notes the latter issue would probably not apply for situations like bending into the inside of a hull since the hull would keep things even. On an outside bend (either over ribands or over a form) I have certainly run into situations where during the bend one part of the piece being bent wanted to bend too much. That is where heavier steel might help. In my case I am bending thwart knees so I will be making rather tight bends over a form...

[This message has been edited by Bruce Hooke (edited 06-15-2001).]

[Bruce Hooke]

Thank you all!
Cecil Borel's idea sounds interesting for a shop that uses 1" wide (and up) bandsaw blades. I just have a 14" bandsaw so none of my blades are anywhere near wide enough for what I am doing (also my bandsaw is only a few months old so I all my blades still have lots of life left in them http://media5.hypernet.com/~dick/ubb/smile.gif). Also, I wonder how hard it is it to drill holes in a bandsaw blade? That is also my concern with using the 'truckers strapping'. How hard is it to drill holes in that stuff -- is it spring steel that needs to be tempered before you can drill holes for attaching the end blocks?.


So far the two best reasons I have heard for thicker steel are to keep the fasteners holding on the end blocks from elongating their holes (TomRobb) and to help keep the bend even and smooth (Mike DeHart). As TomRobb notes the latter issue would probably not apply for situations like bending into the inside of a hull since the hull would keep things even. On an outside bend (either over ribands or over a form) I have certainly run into situations where during the bend one part of the piece being bent wanted to bend too much. That is where heavier steel might help. In my case I am bending thwart knees so I will be making rather tight bends over a form...

[This message has been edited by Bruce Hooke (edited 06-15-2001).]

[holzbt]

Bruce,
If you need to drill a hole in a band or hack saw blade try this. Take a nail about the dia. that you want to drill and cut off the head, chuck it up in the drill press(cutoff or flat side down) and try to "drill" into the piece. This will heat up just that small spot cherry red. Let the spot cool and then drill as you would for common steel.
Roger

[This message has been edited by holzbt (edited 06-15-2001).]

[holzbt]

Bruce,
If you need to drill a hole in a band or hack saw blade try this. Take a nail about the dia. that you want to drill and cut off the head, chuck it up in the drill press(cutoff or flat side down) and try to "drill" into the piece. This will heat up just that small spot cherry red. Let the spot cool and then drill as you would for common steel.
Roger

[This message has been edited by holzbt (edited 06-15-2001).]

[holzbt]

Bruce,
If you need to drill a hole in a band or hack saw blade try this. Take a nail about the dia. that you want to drill and cut off the head, chuck it up in the drill press(cutoff or flat side down) and try to "drill" into the piece. This will heat up just that small spot cherry red. Let the spot cool and then drill as you would for common steel.
Roger

[This message has been edited by holzbt (edited 06-15-2001).]

[Bruce Hooke]

Roger - That's a clever idea. Thanks!

Now I think it's about time to get some wood and a few pieces of steel, crank up the steambox and give some of this a try...

[Bruce Hooke]

Roger - That's a clever idea. Thanks!

Now I think it's about time to get some wood and a few pieces of steel, crank up the steambox and give some of this a try...

[Bruce Hooke]

Roger - That's a clever idea. Thanks!

Now I think it's about time to get some wood and a few pieces of steel, crank up the steambox and give some of this a try...

[Syd MacDonald]

To make the hole, lay it on the end grain of a block of wood, hit it with a center punch and then grind of the bump on the other side.

[Syd MacDonald]

To make the hole, lay it on the end grain of a block of wood, hit it with a center punch and then grind of the bump on the other side.

[Syd MacDonald]

To make the hole, lay it on the end grain of a block of wood, hit it with a center punch and then grind of the bump on the other side.