Author Topic: Steam Engine Base Pattern (Read 57721 times)

doubleboost · « **on:** July 01, 2012, 04:29:15 PM »

Hi
Lads
I have been wanting to make a horizontal steam engine for some time now
As i have a cylinder pattern from my marine engine i decided to make the engine around this
It will be a fairly big affair with no bolts smaller than M6
A simple L shaped pattern is needed for the base
In the past i have used MDF as pattern material
The dust from sanding and machining this horrible material has made me feel poorly on more than one occasion
Rob Wilson donated some Birch ply wood and i had some bits of old Oak shelving (Popper wood)

http://i261.photobucket.com/albums/ii63/john970s0/IMG_3831.jpg

Steam Engine Base Pattern

The basic shape glued together

http://i261.photobucket.com/albums/ii63/john970s0/IMG_3887.jpg

Steam Engine Base Pattern

Car body filler is used to blend curves

http://i261.photobucket.com/albums/ii63/john970s0/P7010133.jpg

Steam Engine Base Pattern

All internal corners need a nice smooth fillet ,in the past i used car body filler (easy to apply but hard work to sand off)
I bought some fillet wax (bees wax) this is blended in to the corners with a ball bearing on a stick.
Much easier and faster than body filler.

http://i261.photobucket.com/albums/ii63/john970s0/P7010139.jpg

Steam Engine Base Pattern

As you add more detail it starts to look something

The Grey bit will be hollow the rest is solid

http://i261.photobucket.com/albums/ii63/john970s0/P7010146.jpg

Steam Engine Base Pattern

http://i261.photobucket.com/albums/ii63/john970s0/P7010148.jpg

Steam Engine Base Pattern

http://i261.photobucket.com/albums/ii63/john970s0/P7010147.jpg

Steam Engine Base Pattern
A coat of high build primer transforms the pattern
John

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jb3cx · « **Reply #1 on:** July 02, 2012, 01:59:25 AM »

looking good john,what size flywheel you going to use ?

Brass_Machine · « **Reply #2 on:** July 02, 2012, 02:16:59 AM »

That is not going to be a small engine! Can't wait to see this one get built.

Is this going to be just a model or do you plan to power something with it?

Eric

krv3000 · « **Reply #3 on:** July 02, 2012, 02:36:01 AM »

well dun john

NickG · « **Reply #4 on:** July 02, 2012, 01:11:45 PM »

It's huge!! Nice work John.

Stilldrillin · « **Reply #5 on:** July 02, 2012, 03:38:01 PM »

The usual, beautiful pattern work John!

Clocked in. Watching quietly.......

David D

loply · « **Reply #6 on:** July 02, 2012, 05:21:33 PM »

That is one big mould for a home shop

What are you going to cast it with?

doubleboost · « **Reply #7 on:** July 02, 2012, 05:54:45 PM »

Hi
It is a fair size
I am trying to work out its volume
I can weigh it find out the SG of Oak then work out its volume
Putting it in to water to measure its displacement is not a good idea
The base will be cast in Aluminium
John

andyf · « **Reply #8 on:** July 03, 2012, 06:44:42 AM »

If you have a reasonable size offcut of the oak, shaped such that you can easily work out its volume, you could weigh both that and your pattern. Then, roughly speaking because of your birch ply and filler, the volumes of the pattern and the offcut will be in the same ratio as their weights.

Andy

doubleboost · « **Reply #9 on:** July 03, 2012, 10:44:43 AM »

Hi
Andy
I was thinking if i weigh the pattern find out the SG of Oak
The formula is
Volume = Weight /SG
John

andyf · « **Reply #10 on:** July 03, 2012, 03:12:14 PM »

Hi John,

According to my inherited 1941 Machinery's Handbook list of "Average SG of Woods (Dry)":

Weight per cubic
SG inch (pounds)
Live Oak: 1.15 0.042
Red Oak: 0.75 0.027
White Oak: 0.80 0.029

Hope this helps, though these figures are supposed to be for dry wood, so I'm not sure what "live oak" is.

Andy

Bluechip · « **Reply #11 on:** July 03, 2012, 03:37:50 PM »

If it's from Machinery's Handbook, they could well refer to N. American species ???

Not sure if they're the same as European Oaks.

Silky Oak is a eucalyptus .... IIRC ..

Long time since I did any wood butchering

BC

andyf · « **Reply #12 on:** July 03, 2012, 04:00:07 PM »

Quote from: Bluechip on July 03, 2012, 03:37:50 PM

Not sure if they're the same as European Oaks.

Silky Oak is a eucalyptus .... IIRC ..
BC

That's why I suggested weighing an offcut of the same wood, the volume of which could easily be calculated.
To add to the confusion, Selly Oak is where I spent 3 years at university in Birmingham.

Andy.

doubleboost · « **Reply #13 on:** July 03, 2012, 04:10:48 PM »

Hi
Had a bit google came up with this
SG of birch ply is 0.67
Pattern weighs 2.2 Kg

Formula is

Weight / SG = Volume

2.2 / 0.67 =1.474 Litres i assume
I can melt 3 litres so it should not be a problem

John

David Jupp · « **Reply #14 on:** July 03, 2012, 05:05:24 PM »

Quote from: doubleboost on July 03, 2012, 04:10:48 PM

2.2 / 0.67 =1.474 Litres i assume
I can melt 3 litres so it should not be a problem
John

Problem is that 2.2/0.67 = 3.28 !

doubleboost · « **Reply #15 on:** July 03, 2012, 05:07:20 PM »

So
It is devided not multiplied
That looks like a better volume

John

Rob.Wilson · « **Reply #16 on:** July 03, 2012, 05:11:16 PM »

ye need a bigger pot John

Rob

doubleboost · « **Reply #17 on:** July 03, 2012, 05:15:30 PM »

You mean like yours

By the time i get some risers and gates in there it will be a good 4 litres

John

Bluechip · « **Reply #18 on:** July 03, 2012, 05:20:45 PM »

Quote from: andyf on July 03, 2012, 04:00:07 PM

Quote from: Bluechip on July 03, 2012, 03:37:50 PM
Not sure if they're the same as European Oaks.

Silky Oak is a eucalyptus .... IIRC ..
BC

That's why I suggested weighing an offcut of the same wood, the volume of which could easily be calculated.
To add to the confusion, Selly Oak is where I spent 3 years at university in Birmingham.

Andy.

Selly Oak ??? That's where Ariel bikes were made.

I had a 350 Red Hunter, a bloke up the road has a 1937 500 VH.

Did you make it ???

I'm off ....

BC

awemawson · « **Reply #19 on:** July 04, 2012, 08:06:57 AM »

You don't need to know the sg of oak. Now it's painted use Archimedes principle to find it's volume. Place a brim full container of water inside a dry bowl. Imerse the pattern so that the water displaced spills into the bowl. Measure the volume of the displaced water - simples !