The Framers Forum

Am I the only framer who hates composite frame moulding - plastic. I aviod the stuff like the plague but have one customer who supplies me with the moulding - plastic. I never achieve a satisfactory result. In my opinion it doesnt cut well on the Morso - even taking the thinnest of slices using the sharpest of blades I fail to get first class joints. I know full well that the same profile in wood wouldnt give me a problem. Any usefull suggestions - apart from the obvious one - dont touch the stuff.

I have used it once, never again.Its more trouble than its worth.

We use about 10 plastics. Perhaps we have been lucky with our choice of profile, but we are happy with the results so far.

Don't use for massive frames though, as they tend to sag a bit under their own weight.

We handle/join them much the same as the timber profiles, PVA glue seems to be ok, though I understand there is a special adhesive available.

In spite of this, I still prefer to work with wood (regardless of it's inferior conservation qualities).

Likewise.... Tried many profiles a few years ago. More trouble than they are worth. As it happened a customer came back a while later and wanted 'real frames' (wood).

Like you Mark, even with the sharpest of blades on the Morso and only one wedge half way on the moulding width, it just did not go together properly.

More so - do you cut on the Morso - or saw? - My joints are bad because the Morso seems to crush the finer part of the frame - It may well be that the stuff I am using is just very poor quality - customer is going to get such a large bill that he wont inflict plastic on me again.

Hi Mark,

The clue is in the name. Of course, I cut the plastic with a Morso.

A couple more points for anyone considering plastic.

Always choose a 'dense' plastic, avoid the open 'honeycomb' type.

A good pneumatic underpinner is essential. Our Cassese 276 has enormous clamping power, which counters the wedge's tendency to force the joint apart as it is driven home.

its the stupid questions that sometimes give the most revealing answers!!

Hi guys

I have to come to the defence of the much maligned "plastic" mouldings. I suspect if you think of them as "plastic" with all the connotations that term conjures up then you will almost certainly not be predisposed to them. I prefer the term "synthetic" or "man made" and have used them for many years.
I would go further and say that in comparison with wood I have a fraction of the problems - no warping - no knots in exactly the wrong place requiring the use of 3 lengths instead of 2 - no drying out banana shaped once unpacked. Further they are a fraction of the cost and if chosen carefully are almost indistinguishable from traditional wood based mouldings.
I do admit however that synthetics which imitate wood are not terribly successful although there are some exceptions however in gold and silver mouldings they more than hold their own.

Joe

Joe
whilst I would agree that some of the finishes are vey good on synthetic mouldings - In my experience the quality of the synthetic material used can vary enormously. I suspect that if you are set up to use composite moulding then you can get good results. I dont like the way the material cuts and find that fixing backs - hangers etc can be a bit hit and miss. I dont like to produce anything but my best work and find my inability to get to grips with this material very frustrating.

Hi Mark

You are right that the quality varies enormously but so does the quality of wooden mouldings, however if you use the good ones they are well worth persevering with.
I have lost track of the amount of times a rep has shown me some new gold or silver moulding at around 80p to £1.00 per foot or even more and I have produced a not dissimilar moulding at a fraction of the price - no competition.
As far as the final product is concerned if you find a moulding difficult to work with then you are quite right not to offer it but again this in my experience applies to quite a few wooden mouldings as well as some of the inferior synthetics.
Not sure what being set up for synthetic means we have a standard morso and pneumatic underpinner which are used for all mouldings.

Regards

Joe

When joining plastic, be aware that often a static charge builds up causing the face of the mitre to pick up loose debris and prevent you from achieving a tight joint.

two hydrogen atoms walk into a bar. One says, ' I think i've lost an electron'.
The other says 'Are you a sure?' The first says 'Yes, I'm positive'.