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Steam Bending Wood, 1" Thick Kiln Dried Ash | Stagecoach Tops



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the top for this mountain stage is what

I was requested to bend the bows for and

this is the pattern and measurements

that I was sent to the right are

pictures of an original coach still on

display so the first thing I needed to

do was make the form that I could bend

the bows around this is just some scrap

2x6 material that I had around it

doesn't have to be very fancy and you

see here the inside radius needs to be

seven and three-quarters of an inch so I

took a piece of plywood and I made a

pattern that I could pattern off of for

the end of these two by sixes

now these bows need to be 55 and 3/4

outside so I'm gonna undersized this to

accommodate the thickness of the bow

itself and to allow for spring back when

I actually bend these bows at least two

by sixes aren't quite wide enough as

they stand by themselves so I'm gonna

add a little piece to each end for

additional depth in the radius these

forms don't have to be pretty they just

have to be structurally strong enough to

withstand the pressure when the wood is

being bent

in the center I'm going to add a steel

post that I use to adapt this form to my

bending press so when I build my press I

designed it to accept a variety of forms

and this is just one of the styles that

I use on this press now if you watch my

video on steam bending sheep wagon bows

this is the band that I used when I bent

those bows underneath this band I have

some pipes welded at different positions

I'm going to bring my cable ends in to a

closer position and attempt to use this

band when I first Bend my said a bolt

we're gonna find out eventually in this

video why this was not the best idea now

the plans called for one-inch thick ash

inch and 3/4 inch wide to make these

bows so I selected the lumber I wanted

to use and went ahead and build it to

size

now the order was for 15 bows so I

needed to go through and decide which

ones were actually bendable the rule of

thumb is less than one inch of run-out

per foot in the grain this piece you can

see here is way sharper than that so I'm

actually going to take and recheck this

one set it aside but most of these you

can see the grain run-out is about right

at a foot so I'm going to consider these

bendable and I'm going to use a quarter

inch roundover bit and just take off the

sharp corners

the boiler that I use for steaming is

coal-fired and it has about a 20 to 25

gallon capacity I take general household

ammonia non sudsing and I'll add about 2

cups to the boiler itself this will add

to the penetration of the steam when

they are in the steam tank when I begin

to show signs of steam I'm going to load

up 3 and Bend 3 at a time as this begins

to build pressure you can see some suds

starting to come out around the door I'm

going to go ahead and put a center mark

on my form so I know where to line up my

banding then from my notch that shows

the center on this band I'm going to

measure back three and a half feet

because the board's I'm going to bend

initially are 7 feet so at these marks

I'm going to clamp boards on the band to

act as stops and remember when we're

bending wood everything has to be

compression so I don't want these bows

when they come out of the steamer to be

able to stretch but I want to keep them

contained so that all the bending goes

into compression this board on the right

I'm going to clamp down fairly securely

then I'm going to take one of the extra

pieces as a yardstick so to speak and to

put it in to show me about where the

location of my board on the Left needs

to be this one I'm not going to clamp

securely until I actually put the bows

in getting ready to be bent

now I always bend under pressure which

helps force the steam and the moisture

in and since this material is kiln dried

ash one inch thick I've allowed it to

cook for two hours now I'm ready to go

ahead and get some bent the block on the

Left does not yet clamp securely so I'm

going to go ahead and tap it into place

so it butts up against my boughs now you

can see where I have five clamps on each

end of these bows

so while this is bending I've got the

camera moving around I'm a little jumpy

so I apologize for the quick movements

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the left side came up fairly straight

but the right side was a little behind

like just to come along and brought it

into position so when I finish this been

digested both sides to where they were

fairly straight up and down and here it

actually looks like they bent pretty

well to get these off the form

eventually I need to have some framework

to contain them in so I click built

biceps these bows have now set for a

couple hours and cooled down so I can

take them off and put them into this

little framework that they're gonna dry

in now through this short little clip

I've actually stopped it twice to let

you see that the amount of spring go

back was about four inches overall two

inches on each end right here you can

see it's standing up I have to push it

down about four inches

and here once again

so I could just end the video and show

you this and say everything went really

well and that's how you do it the truth

is that isn't so I looked at these and

there were a couple of bows that had

these stretch marks on the outside of

the band so I went back to examine why

as I measured between my two blocks I

see the blocks had stretched out been

pushed out about an inch so my five

clamps were not sufficient to keep this

wood contained also my four inches of

spring back needed to be accounted for

so I'm going to take my form off knowing

that I'm going to now over bend I need

to over bend about two inches when I do

that I don't want this sharp corner to

put a crease into the bow so I'm going

to take and round this corner off on

both ends of my form

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another thing I'm going to change is the

style of the band I have some bands that

I use when I bend to inch stick part

wood and there I've welded ends on on

each end of two by quarter inch angle

irons I'm going to use these bands now

to bend the next set of bows and these

will not be allowed to stretch also the

pulleys on my press they change the

direction of the cables I'm going to

drop that down so that my direction of

inward pull is lowered I also keep some

1/8 inch banding handy as quick shims to

accommodate for any variation in length

so if my wood is a little short I'm

going to put whatever I need in to shim

it out to keep it as tight as possible

against these ends

so now we're going to try this once

again

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again if you've watched my other steam

bending video you know that this press

runs at 1800 to one reduction so it

moves fairly slowly

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so as the ends of these bows start to

get close to vertical my cables are

pulling more upward than inward so I'm

actually going to stop it

and I'll use some come along to have a

direct end pull I'm going to put a

come-along on each side and actually

bring these in to over bend them to

compensate for the spring back

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now you can see I have them over bent

but I'm gonna take a carpenter square

and actually adjust these so I have two

inches on both sides over bent this

should allow for the two inches of

spring back that that's going to occur

the right side initially I had three

inches the left side was not quite two

inches so I made a couple adjustments to

where we had two inches on each side

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so is the finished Bend this is what I

ended up with after these have set for

at least two hours I'm going to take

these off and put them into the

framework we'll look at them closely and

see if they're going to work now if you

look at the top of these bows you can

see that they actually kind of recurve

backwards a little bit we're gonna

address that in a minute so now they go

into the framework with hardly any

downward pressure at all they turned out

really well

these no longer showed any sign of any

stretch marks

having the solid ends made all the

difference now this is the recurve on

the end of the bows since there's still

moisture in these I can take them and

actually put them in a vise and

straighten this back out by causing the

the inward fibers to stretch back out

this wood is still fairly elastic and

pliable at this stage

so this is our finished product

these actually add some pretty nice

straight grain no buckling on the inside

no stretching on the outside we have our

fifty five and three quarter inch OD

that our pattern called for we are a

one-inch thick an inch and 3/4 wide

bending three at a time we have almost

five and a half inches of width that we

bent at one time here we have a second

set of bows and we finally ended up with

all five so we had our 15 bows I had

three that I had rejected because the

run out was worse than the 1 inch and 12

inches there were some wavy grain and

these were not ideal so just for

demonstration purposes I put these three

and the steamer and put them through the

same process as I did all the rest just

to show that you don't always have to

have perfect ideal lumber if you have

the correct banding and that they are

contained properly even less than ideal

kiln-dried hardwood lumber will Bend

this run out was in about five inches

and even the wavy grain bent

there was no stretching on the outside

and these actually were usable bows I

didn't include these bows in the order

of the 15 I just bent these for example

purposes so these are our 15 bows thanks

for watching

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you

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