Making a small vase shape?

[T i m]

Hi All,

Sorta following up from the small woodworking lathe thread (and learning a nice lathe solution might be a bigger project than I realised) I'll ask the panel if there might be a better / easier / cheaper way.

Our daughter has a school GCSE design project that requires her to make a 3d model of her design (a perfume bottle .. on a particular theme).

Her design is something that looks like a typical basic flower vase (thin neck curvy waist / bottom) but with the lower end (from the waist downwards) cutout so it ends up standing of 3 tapering legs (like it had been standing over a ball when it was made).

She's requested to do the project at home rather than school because she want's to make a nice job of it.

So, my first though was to get her (with suitable tuition, she's good with that sort of thing) to turn the basic shape on a wood turning lathe (something I wouldn't mind adding to my workshop tools anyway) then to rough out the shape at the bottom somehow (bandsaw?) then maybe finish the rest by hand (glass paper / Dremel etc)..

The final object is supposed to be in glass so a nice glossy paint job should help that effect.

So, can anyone think of an easier / better way of doing this (with typical d-i-y hand tools and readily available materials preferably) please?

All the best and thanks for your time ..

T i m

[Owain]

Presumably part of the challenge is to envisage how this might actually be made for production...?

I'm not sure *how* it could be made for production, but a couple of thoughts for the prototype:

a) section it into horizontal slices (a 3D CAD program should be able to do this) i.e. "contour lines", cut each slice out of clear acetate, glue together. The thinner/more slices, the smoother and more accurate the finish.

b) clay should be both turnable (on a potters wheel) for the 'vase' and manipulable for the 'legs'

c) blow it in glass, with supervision from a glass-blower

Theatricals use 'sugar glass' for breakable props - not sure how that works, there's a group something like alt.theatre.stagecraft might now.

Microwave fudge is manipulable by rubber-gloved hand in the soft state, reusable and, if the project fails, edible.

Owain

[Brian Reay]

The school "DT" department show have some polystrene type material that is very easy to work. The stuff I've see the pupils at school use is blue and very fine textured. It can be cut, sanded, and sealed for painting. Glue some "slabs" together and cut the shape out.

OR

Use the about to form a mould for some plaster of paris.

OR

Some modeling clay and "form" from that.

OR.

Find something simlar in shape, cover in paper mache. When dry, cut paper mache off, remove former, and reassemble the paper mache to form a mould (maybe after varnishing the inside. Fill with plaster of paris. When set, remove paper mache and sand to final shape, maybe adding bits of modelling clay or "Milliput".

Brian

[Andy Dingley]

Like this ?

was yellow builders foam cut with a breadknife, scalpel and sandpaper, then used as a pattern for lost foam casting in sand of bronze (melted coins).

You might also find some useful guidance by web searching for "ball and claw feet". It's a well known bit of furniture caving, although the ball usually stays in place.

That sounds sensible, although I'd expect a hand-held coping saw to me more reliable than a bandsaw. Arrange good clamping of it first.

[T i m]

Ah, that sounds good, I think I can imagine what you mean and I'll ask her if she's seen any at school (one of the few teachers that she really get's on with is her DT teacher so that should be easy ). I did think of typical expanded polystyrene but that would break up too easily (especially in this smallish scale). Is this foam similar to that green 'Oasis' they stick flower arrangements in?

Yes, another good thought once you have the above.

That was one of the options we had already considered but wasn't sure how easy it would be to get reasonably symmetry or if it would take the fairly fine tipped 'legs' without them breaking off.

I like the sound of that method (assuming you can find a suitable 'plug') because it can reproduce the symmetry of the template. Then I'm not sure how we would hollow the bottom section (it would look like a downward facing 3 fingered alien claw).

I think the best option so far (assuming we can get the material) would be the foam as I guess it would be reasonably easy to carve out and could be coated with some epoxy resin (or similar) to give it some strength then sanded / filled / painted. ?

Also she could set the scale and easily / safely do it all herself (very important for a potential designer).

All the best and thanks for your input Brian.

T i m

[T i m]

'feminine' ..?

So this 'builders foam'? Like 'lost wax' then? . Isn't it illegal to melt (our) coins?

Ok, ta. I think she's pretty well got the design drawn up so (all part of the courseware) now it'

Ok and thanks (again) Andy.

If it was made of wood I was going to look into turning the basic external shape on the lathe then cutting it lengthways into 3 x 120deg 'segments (top to bottom, like orange segments). The insides of the claw could then be cut out / worked easily then the segments re-glued (with saw cut with spacers to maintain the section) and then finished off when back as a single item? A bit more faffing about but could result in a nice item?

All the best ..

T i m

[Brian Reay]

It is very similar, come to think of it. Maybe a bit more "solid". I've not used it myself but have seen it when doing "cover lessons" etc. in the DT department.

Use a wire "skeleton" set into a hole in the body with epoxy, then mould the clay etc over it?

You may end up with some bits that needing fixing on later.

You can get (in model shops) "paint on" latex that you peel off to make a mould- like youngests often have to make "Winnie the Pooh" type ornaments.

Or covered in paper mache.

Check with the teacher where the emphasis is in the mark scheme. If it is in the design process and not in the "finish" of the prototype then the focus should be on the design process and she can use the problems in making the prototype as examples of how she appreciated the manufacturing problems.

Yes, it get messy when pupils hack off bits litter the school with them ;-)

Glad to help.

[Brian Reay]

ones on the market) with turning tools, screw chuck, and maybe some other bits I'm trying to dispose of (a stroke has left me wary of a wood lathe).

I'm in Nth Kent, Email on website.

[Alan]

In message , T i m wrote

As a design exercise your daughter should be rejecting a potential design that may break during manufacture or, worse still, when it gets to the retail outlet.

[T i m]

Hmm, good point (and one I'll bring up with her) although I'm not sure just how deep they go with this sort of thing, ie, how much 'fantasy' is tolerated in their design?

Maybe if it was made from a plastic it would still be 'dooable'?

Thanks for the feedback Alan .

All the best ..

T i m

[Tim Lamb]

In message , Andy Dingley writes

A variation on this is to form the basic shape by turning or as above and then clad in pottery clay (strip or coil). The feet could be moulded on a suitably sized ball, cut out, peeled off and attached to the slab pot.

Quite how dangerous vaporised foam is in a pottery kiln remains to be discovered:-)

regards

[T i m]

Ok, I follow you. The 'looks like it was moulded over a ball' idea is my best way of describing how she has come up with this design for the perfume bottle. Like a cross between an old fashioned space ship (Flash Gordon stylee) and a traditional vase or Roman flask? It was supposed to be 'different, be attractive to the Ladies (so smooth lines etc) be practical (ie it would stand up on it's tripod feet) and she thought the idea that the package would hold less that it looked might appeal to the marketing people. ;-)

The point being is it's her design and would like to be able to facilitate in allowing her to achieve that however impractical it may be in the real world (as catwalk fashion is to Peacocks etc). As 'Alan' quite rightly pointed out there may be 'other' implications re a design that could be dangerous or impractical (thin pointy glass legs etc) but learning that for herself (or examiner feedback) might be part of learning process. She might just be able to add a footnote in her supporting documentation to that effect?

If we use this process and can get back to you you will know it was ok ;-)

All the best ..

T i m

[T i m]

It might be Owaid but to be honest I've not really been involved with the project till this 'I've told then I want to make it at home' thing came up. The other 'pity' is she dreads having to leave any of her work 'out' (and that's likely as most of her efforts end up on display somewhere) as it get's graffiti'd or just damaged in some way. One of the local kids is in her year and is known to just wander in a room with a hacksaw blade and cut someone's work in half .. I've seen him smashing up his siblings toys in the road when he was 6 years old .. (and stopped him smashing up shopping trolleys and street furniture myself) .. something wrong with that one ...

ok ..

Understood. I have seen other work at the college she is due to attend with similarly constructed stuff on display. I have seen it used simply for construction (then filled over) and left as-is, as part of the effect.

My description of the finished item wasn't very good but if you imagine your typical shape vase (bulbous base and then thin neck opening out a bit at the top) but then cutting 3 arches out of the bottom (120 deg apart) leaving the vase (that would now leak of course ) standing on 3 bandy pointed legs (like standing on tip toes).

Ohhh, that *would* be nice, especially as she envisaged the final product to be in glass .. not sure where / how though ..

Ok, worth a thought (could be could molded in a paper mache / plaster / rubber mould etc).

I like that one best! ;-)

All the best ..

T i m

[T i m]

Hi Brian,

I have sent you an e-mail (in case your spam filter has eaten it) ;-)

All the best ..

T i m

[Thomas Prufer]

Well, if you do -- how about Maji-Plast, aka Morph-Plast?

Google for it -- "SIMPLY MELT GRANULES IN HOT WATER OR MICROWAVE OR EVEN WITH A CIGARETTE LIGHTER PRODUCT WILL TURN FROM WHITE TO CLEAR, AND IS THEN KNEADABLE, MOLDABLE AND WORKABLE TO ANY SHAPE OF YOUR DESIRE FOR AROUND 5 MIN..." is wot they shout. Like hotmelt glue crossed with putty?

I've never used, just heard about it.

[Mike Dodd]

Something like

?

[Thomas Prufer]

Thomas Prufer

[The Natural Philosopher]

Laminate from thin cross sections and carve and sand.

I've been using this to make up propellors..it saves an immense mount of material removal. And you have lines of 'cut to here, but not beyond' to use as a guide..

[Andy Hall]

Make propellors? I thought they were reasonably inexpensive, or is this for special designs for electric flying to eak the last bit of energy out of them?

[T i m]

Thanks guys, another option there.

Worth getting some to 'explore' even if not for this project (always handy to know what's out there to make stuff with).

All the best ..

T i m