Oversize Chicken Eggs

 

Giant chicken egg

Giant chicken egg

These oversize chicken eggs were made for a theatrical production. The oversize eggs are 60cm high and made from fibreglass for strength so they can be sat on.

The first step was carving a polystyrene oversize egg so a fibreglass mould could be made. The mould construction is described in another post. After the mould was finished two oversize eggs were cast. After the fibreglass halves were joined together they were painted.

One of the oversize eggs was made with a broken top so something could *hatch* from it on stage.

Assembled cracked egg

Assembled cracked egg

Cracked egg with top removed

Cracked egg with top removed

Making A Giant Egg

Completed egg shells

Completed fibreglass shells painted in shellac ready for finishing

The first step in making a giant egg is to make a giant egg – so a mould can be made.

Depending on the size of the egg you want to make will dictate how you go about making the egg form. Since the egg we needed to make was about 60cm tall it was decided to carve it from a block of polystyrene. Since the egg shape is symmetrical it is best to turn it on a lathe.

Preparing polystyrene block for turning

Preparing polystyrene block for turning

The polystyrene has to have plywood boards glued to both ends so a lathe faceplate and tailstock centre can be attached so it can be turned on the lathe.

The corners of the block are then cut off at 45 degrees to make turning a bit easier on the polystyrene. If this is not done it is likely large chunks will break off when the lathe chisel is applied to the turning block.

It is very, very messy turning polystyrene on a lathe so ensure the work area is covered with something to collect the shavings and clean up regularly as you work. This will minimise the polystyrene getting into every nook and cranny of your workshop.

Polystyrene mounted on the lathe ready for turning

Polystyrene mounted on the lathe ready for turning

Basic shape completed on the lathe

Basic shape completed on the lathe

Completed polystyrene egg

Completed polystyrene egg

The polystyrene is removed from the lathe and the two ends trimmed. Sandpaper is used to smooth both ends until their radius makes a smooth transition around the egg shape. It is important to get the shape exactly right with no obvious flat spots or sudden changes in the radius.

To support the egg while making the mould a box was built to put the egg form into so the middle flange can be made with plasticine. Once that has been done it is given a coat of PVA mould release in preparation for fibreglassing.

Ply box for making the top half of the mould.

Ply box for making the top half of the mould.

Flange finished around egg

Flange finished around egg and mould release applied

After the top half has been fibreglassed a timber support is fibreglassed on the mould so it sits horizontal when put on its side. The egg with the first half of the mould attached is removed from the support box and turned upside down to expose the underside of the egg form. This is cleaned up, PVA mould release applied and the second half is coated with fibreglass as described in previous mould making posts.

After polishing the inside of the mould halves with wax fibreglass casts are taken and trimmed to the flange line around the mould on both halves.

The two completed fibreglass mould halves

The two completed fibreglass mould halves

Fibreglass casts for egg ready for joining

Fibreglass casts for egg ready for joining

To ensure that both halves of the egg are joined together securely they need to be fibreglassed along the inside centre seam of the egg. To do this an access panel is cut in one half that is big enough to get your hand inside the egg shell. Blocks of wood are attached to the inside of the shell around where the access panel will be cut. This allows for easy re-installation of the panel section after the work has been done.

You can see the alignment blocks in the photo below with the access panel removed.

Cutting out an access panel in one half

Cutting out an access panel in one half

Access panel removed

Access panel removed so halves can be fibreglassed together

The two halves are taped together with mylar tape to keep them aligned. They are then fibreglassed on the inside along the centre seam. Once this has been done the access panel can be glued back into position and all gaps around the panel opening and the centre egg seam can be filled with polyester filler.

After sanding smooth the fibreglass is given a primer coat of de-waxed shellac.

Halves taped in position

Halves taped in position for fibreglassing from the inside

Access panel glued back in position

Access panel glued back in position and gaps filled and sanded

The completed eggs can be seen in this post.

Abstract Display Tree

Abstract display tree

Abstract display tree

This abstract display tree is constructed from 18mm MDF and breaks down into two sections for ease of transportation. Its assembled height is 2.4m and the width is 2.1m.

The tree consists of two hinged MDF half sections that fit into a steel alignment bracket on the floor which makes it very stable once erected. Each quarter panel of the tree was laser cut in 18mm MDF from four different DXF files. The two quarter sections of each half section are attached together by hinges. Each half is free standing when it is opened up to 90 degrees.

After each half is opened out to 90 degrees is fits into the steel alignment star as shown in the photos below.

The two folded MDF sections ready for transport

The two folded MDF sections ready for transport

Alignment brackets

Alignment brackets for the folding halves of the tree

First half fitted into bracket

First half fitted into bracket

 first half in the bottom bracket

Another view of the first half in the bottom bracket

Second half fitted into base bracket

Second half fitted into base bracket

View of top locating bracket

View of top locating bracket

Interior Window Security Bars

Inside view of bathroom windows

Inside view of bathroom window security bars

Many older style homes and units have outward opening bathroom windows which makes it difficult to install suitable security bars. The solution we offered a client was to install them on the inside of the bathroom windows.

Interior security bar installations present their own set of difficulties not least of which is being able to open and close the windows which are now behind the bars.

These particular windows have a long arm which needed to be able to swing up from the locked position and then pivot out to push the window open. This was achieved by using a cross motif in the design which allows the opening arm to be manipulated through the open areas of the bars.

Window opening arm operation.

Window opening arm operation.

Exterior view of bathroom windows

Exterior view of bathroom windows

Oversize Tiffany Style Gift Box

Oversize Tiffany style gift box

Oversize Tiffany style gift box

A dance prop in the form of an oversize Tiffany style gift box was required for a competitive dance routine. The box was to be big enough to conceal the dancer inside and light enough so it could be carried onstage for the routine with the dancer inside. It also had to be strong enough on the top so the dancer could perform her routine on the lid.

For rigidity the dance prop frame was constructed using 12mm hollow square steel with extra braces in the base and lid sections for additional support. To keep the weight as low as possible it was clad in 7mm marine ply which was liquid nailed to the frame. Small hand cutouts were cut in the sides to enable it to be carried and a small lip attached to the front of the lid to make opening it easier.

When the dancer burst out of the oversize box by throwing open the lid it put considerable stress on the lid stays. These were custom made using 3mm flat steel to stop the lid opening too far so the dancer to get out and close it easily. Another 30cm square wooden replica of the oversize box was built to act as a step to facilitate the dancer stepping up onto the closed lid. This was incorporated into the routine to make the transition as seamless as possible.

Tiffany style box opened

Tiffany style box opened

Heavy duty hinge stays

Heavy duty hinge stays to support the lid

Steel Balustrade Railing Restoration

Steel railing restored to its original condition

Steel railing restored to its original condition

This steel balustrade railing had suffered from severe corrosion resulting in many sections of the design being lost making it look unsightly and in need of restoration.

Before the restoration could start custom bending jigs needed to be made so the new sections of the missing design could be fabricated. The new parts and sections were made in 25x3mm flat steel to match the existing design. The corroded sections were cut out of the balustrade railing and the new sections welded into place to complete the restoration.

Damaged section of the steel railing

Damaged section of the steel railing balustrade before restoration.

Removable Window Security Bars

removable window security bars

The Art Deco style removable window security bars

A client wanted some Art Deco style removable security bars for her bathroom windows. Because it was a block of flats she wanted the removable bars mounted on the inside of the windows so that the outside appearance of the building wasn’t affected.

The security bars use a simple ODEON Art Deco design which is mirrored in the opposite window to achieve a more balanced look.

The removable bars are held in position by brackets fixed into the bottom of the window frames and locked in position by two standard window locks attached to the top section of the security bar frames. The bars can be removed by removing the two pins in the locks and pivoting them forward and out of the bottom brackets.

The pictures below illustrate how the removable bars are fitted/removed.

windows before security bar installation

Bathroom windows before security bar installation

Bottom brackets to hold security bars in position

Bottom brackets to hold security bars in position

Detailed view of a bottom bracket which secures the base

Detailed view of a bottom bracket which secures the base

security bars into the bottom brackets

Fitting the security bars into the bottom brackets

Locking the bars in position

Locking the bars in position with the top securing pin

securing pin locked in position

The second bar securing pin locked in position