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Main Cylinders

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142 records found. Page 9 of 15 displayed.

For most of the photos on this page, you can click the image for a larger picture.

Highslide JS With the main patterns for the motion and valve cylinders nearing completion, Tony's thinking is moving on to the other parts of the cylinder casting. If you look at the first page of this section, you can see that the cylinder is attached to the main frames by a flat plate, part of the casting. As the pattern will be split into 4 horizontal sections, this needs to be reflected in the plate part of the pattern. In the photo you can see the 3D printed model of the cylinder with one section in the centre of the image. The bottom right area is the mounting flange and Tony is working on laminating the sections.
Highslide JS The second of the 2 flange section patterns with the glue setting. Yet another example that you can never have enough G cramps in the workshop!
Highslide JS Tony now needs to bring the valve cylinder section down to the final size. To do this he has made a template out of recycled drawing hardboard.
Highslide JS Tony is now making the finishing cuts on the first half of the valvecylinder pattern. Roughing cuts are now disappearing as he gets down to size using the templates. Finish sanding and filling will remove any minor imperfections as usual. The best thing about finish sanding on a lathe is it requires no elbow grease!
Highslide JS This is the steam chest end of one half of the valve cylinder pattern. The steam chest is the area between the 2 valve pistons that run in the smaller diameter area of the pattern. With the regulator (i.e. the throttle) fully open, if the steam chest pressure gauge is very close to the reading on the boiler pressure gauge, that shows that the steam pipes from the boiler to the steam chest are efficient.
Highslide JS Here is the first half of the valve cylinder pattern nearing completion. The view is looking at the joint end of the pattern where the male tapered plug will connect with a female tapered socket on the other pattern. Tony needs to do a small amount of turning here before completing the sanding and general filling in the general 'dings'.
Highslide JS Tony has to generate dozens of small templates to ensure the pattern is correct. Here is another one being used to check the joint end of the first half of the valve cylinder template
Highslide JS Meanwhile on the other half of the valve cylinder template, Tony is using the power planer to prepare the pattern for the lathe. The hand plane is also used to tidy things up.
Highslide JS One of the upsides of the lockdown has been that Tony has been able to push on with the turning of the valve cylinder pattern. He's now hit one of the downsides in that he needs to get the first completed half of the valve cylinder pattern off the lathe so that he can start on the other half. Here you can see the completed half on the lathe with its taper plug joint so allow it to connect with the other half of the pattern. Nearest the camera is one of the "quarters" ready to go on the lathe.

Attention will now be turning to the manufacture of templates for the cores which create the air spaces in the assembly. Keith and Tony have been working closely together in preparing drawings. This has exploited one of the many advantages of modern Computer Aided Design software. Keith has been adjusting the size of the "prints" (i.e. the parts of the core pattern that locate the core in the sand mould) to ensure that the core is balanced and doesn't topple over when placed in the mould.
Highslide JS Autumn 2020 and Tony is back in the workshop. The cylinder bolts to the locomotive frames via a large flange. As our cylinder pattern is in 4 horizontal sections, so we have to make the flange pattern in 4 horizontal sections. To start with, Tony has contacted his local CNC machining company and has had 4 MDF templates produced. Our CAD expert, Keith, has generated the files from our cylinder model and has passed them to the CNC company. With the templates, Tony will use a router to cut the pattern to size. As the router has a bearing to control the cutting head, the template must be undersize to accommodate it. The first image shows the MDF template and the flange pattern blank, ready for routing.
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142 records found. Page 9 of 15 displayed.