At keystage 3 I would have a card making project, most schools have a wet area and I would use this as a source of wild flowers. The first part of the project woulod be collection and pressing followed by card making.

At keystage 4 I would widen the project to include picture making using coloured flowers as ink.

Flower Pressing

More Flower Pressing

The original idea came from watching my better half arranging cutout paper flowers on a birthday card. This reminded me of the art of flower pressing and it came to mind that the preserved beauty of a real flower would look far better than a paper imitation. So I got the sketch pad out and tried some initial ideas.

For many years flower pressing was done in the home (Many houses having a small library) using books as improvised presses. This would often result in the books being ruined by the act of drying out.

I decided that a three clamp system would guarantee the most even pressure and keep the two halves aligned with the minimum of twisting, 2 would be inherently unstable and possible impossible to even the stress, 4 or more would suffer from internal triangulation of the stress again making it hard to have equal pressure on each bolt. If you have ever changed a wheel you know the importance of tightening the bolts in a pattern to reduce the chance that nuts are left loose.

Having considered the possibility of threading the bore of the clamps a colleague suggested a captive nut, an idea that I snapped up as it introduced a standard product to the project (A must for GCSE) and it would allow a pupil to research nut sizes to predict the size of hexagonal hole that needed machining.

The Flower Press shown here is made from one piece of hardwood approx 250/250/80 but it could easily be made from a similar sized piece of pine or pieces block glued together or two pieces of 18mm MDF (Separate pieces not needing the splitting operation. This finished depth of wood / material is to allow for the potential stresses that could be exerted on the press with a full load of flowers.

The unit is held together with three machines bolts and machined handles with captive nuts.

Handle

The whole unit comes apart to reveal the Card Inserts which have been cut and embellished on a laser. Card or paper is important for the press faces as this controls the moisture release from the plant being preserved. If the press was used without the card then the plant would probable not dehydrate well. Card or paper usually makes a good control to preserve the colour of the flower. The intention is to keep out oxygen to stop rotting taking place whilst allow water to escape to preserve / desiccate the plant.

Parts Breakout

This project will use just about every machine in the machine shop.

Making The Press Faces

Depending on your choice of material the first step will probably be to sit the block on the bed and clamp it using the offset nut clamps.

Machining

A skim program should be run taking 1mm cuts until the whole surface cleans up.

Surface Skim Drawing (2D Design) - Download

Surface Skim Drawing (Millcam) - Download

Red set to 1mm depth with the 12.7mm cutter

IF you are using MDF you will be able to bypass this option but you will require a sacrifice board that the top sheet is well adhered to. (Double Sided Tape.)

The Outline and the holes can be cut in separate operations I chose to do this due to the fact that i wanted the outer channel to be cut with a 12.7mm cutter to clear the Ovolo cutter whilst the holes i wanted finishing with a 6mm cutter.

Hence the the outer circle the Ovolo and the 150mm groove were cut as one program.

Press Face Stage 1 (2D Design) - Download

Press Face Stage 1 (Millcam) - Download

Drawing

Red is set to 30mm Depth Outside using the 12.7mm Cutter.

Magenta is set to 7mm depth Drill (Subject to your choice of Ovolo Cutter) - Set to use the Ovolo in Options

Green is set to 2mm depth Drill - Set for the Engraving Cutter in options.

Machining

Overlo Profile

Groove

Finally using a 6mm cutter the recesses and the holes for the bolts are cut.

Press Face Stage 2 (2D Design) - Download

Press Face Stage 2 (MillDesign) - Download

Jig Pins

Blue should be set to 6mm depth Area - 6mm Tool

Red should be set to the maximum depth the 6mm tool can cut - Area in options.

Holes

Once all the operations are complete the wood is turned over and the same operations repeated.

Turn Over

This will leave you with two halves joined together.

Now comes the fun bit. Using a band saw or coping saw trim the four corners to leave the two halves as one big round block.

Then place in a vice and using a 24 inch or bigger wood saw carefully say down the middle to separate the two halves.

This is long hard work and essential. Every GCSE project needs a hand tools element and this is a big one.

Don't try to saw all the way through after you have cut about 50mm into the blank rotate it 30 degrees and saw some more. If the cuts are straight you should get a minimum amount of grabbing but persevere it will cut into two eventually.

Once the halves are ready for their final machining a location jig needs to be made. This ensures that the wood in placed down in exactly the right place for the Ovolo cutter to cut an even path on the second side.

We will use the three holes as a mounting datum.

Press Face Jig (2D Design) - Download

Press Face Jig (MillDesign) - Download

Red cutting depth is 15mm with the 6mm cutter.

Jig

Glue two pieces of 15mm MDF together to make a jig thickness of 30mm. Drill three holes using the original drawing to ensure that the location is identical. Once the holes have been drilled at the same diameter as the halves. machine some pegs to .25mm larger than the hole diameter and 30mm long.

Using double sided tape locate one half on the jig and proceed to repeat the operations.

half

ie. skim until the surface cleans up and then machine the Ovolo and the grove (Stage 1 only) . Do not move on the the recess or the holes as this could cause the tool to collide with the pins.

Remove the first half then repeat with the second.

Finished

Once the two halves are completed a design can be engraved onto the surface with the laser cutter.

THE BOLTS

The bolts can be made in a number of ways depending on your machines capability.

If you have a lathe with a tailstock centre then the bolts can be made in

two stages.

Alternatively the thread needs to be cut first before the shaft is cut. If the bolt is cut before the threads then the length of bar will not make for accurate thread cutting and the material will bend.

bolt

Stage 1 is machined between centres due to the length sticking out of the chuck.

Stage two (Parting off) after the centre has been removed.

Press Face Stage 1 (Boxford Lathe Profile) - Download

Press Face Stage 2 (Boxford Lathe Profile) - Download

Secondly some washers will be needed to sit under the clamps.

Washers (Boxford Lathe Profile) - Download

The Jig will also need some pins making.

Jig Pin (Boxford Lathe Profile) - Download

The Clamps

Manufactured on the milling machine from 70mm bar.

After clamping there needs to be at least 16-17mm of bar protruding from the clamp.

This unit again is made in stages.

Handle

Stage 1. Is done with a 8mm and 6mm tool.

Clamp Stage 1 (Boxford Lathe Profile) - Download

Red Depth is 14.7mm - Area

Green Depth is 7mm - Area

Clamp Stage 2 (Boxford Lathe Profile) - Download

Finally using a 10mm Drill with 45 degrees the top edges are chamfered.

Clamp Stage 3 (Boxford Lathe Profile) - Download

Finally the Clamp Nut is chamfered to take away the sharp edges. the tool is the 10mm drill set to a depth of 2mm.

Once the machining is done. The hand skills return as each clamp needs to be sawn away from the bar. (Tip. Saw down each leg to the middle.

Once the handle is free. It can be polished on some emery cloth to remove the saw marks.