The Framers Forum

Ok that has your attention....

Polymorph is a thermosetting plastic, supplied in small pellet form, that can be moulded into any shape after heating to 62C. Recommended heating method is to immerse in hot water until pellets become clear. Drain water and mould by hand. Note that the plastic becomes opaque when cool.

The plastic sets hard when cooled and can be reused by re-heating. Its uses are extensive but the reason I am mentioning it on this forum is that it may help when underpinning awkward shaped mouldings.

In its "raw" state:



After heating & pressing into the moulding profile:



Moulding pattern visible:



Moulding & plastic inverted and flattened on bench to produce a "flat" for the underpinner pressure pad.



This was my first attempt but I was able to place a wedge located half way down the the inner "valley" on both sides. This would have been difficult with my normal underpinner pad options.

Anyway food for thought.

Polymorph is available from Maplin and a few other places.

http://www.maplin.co.uk/Module.aspx?Mod ... =2&doy=8m1

Thanks Pat!
A small amount could also be used under the back corner of a moulding when chopping. Some mouldings these days have the bottom back corner chamfered and when the 'compo' is brittle it chips off. This might help to support and prevent chipping.

I will have to see whether it's available down here in 'paradise'.

I want some to play with!

Interesting stuff! I presume you can reuse the blob on the same moulding again & again?

Yep, I would also think that a piece of thin felt could be placed on delicate mouldings to prevent damage.

osgood,

If you cannot locate any then I can easily send a 250gm tub for experimentation. Price from Maplin is about UK13 + shipping.

What a clever idea, Pat!

Thanks Pat.
I will investigate the possibilty of getting it down here, next week and if I can't get it I will contact you!

What about making a chunk to fit snugly in the back of scoop-back mouldings when cutting on a guillotine? The first cut would go though the plastic, making two halves which could be tacked to the motso fences with ds tape to hold them in place for subsequent cuts. Could save lot of filling. The two bits could be saved until you cut the same moulding again.

Nice one Pat.

The material is soft when hot and should be able to stand a morso cut without distorting. However when cold the material is akin to nylon and can be worked in a similar fashion ie sawing, drilling, filing etc. It may be more appropriate to work with it cold.

Polymorph and similar products have been around for quite a while now. I first came across it while working in the formula one racing business where they used it for transfering shapes from patterns to moulds.

It was already in use in the medical industries long before this, in connection with making moulds for individually made supports for the disabled. There are a number of different polymorph type products available with different characteristics.

Another interesting, but different family of products is polymer clay. It's unlikely to be suitable for this particular application, but may well find other equally interesting uses.

Oddly enough (if my arithmetic is right) it's cheaper to buy the small, 170g, packets from Maplin than the larger ones.

Maplin are currently advertising 250gm & 500gm tubs however a cheaper source is:

http://www.mutr.co.uk/catalog/product_i ... cts_id=550

1kg for £15+vat and they can supply 4kg for £55+vat.

nice tip Pat, thanks.

Hey, thanks, Pat!

I've been struggling with supporting awkward profiles on my Logan Studio Joiner and I've had a packet of Polymorph in the house for ages.

I never, for a minute, thought to combine the two.