The Framers Forum

I've had a customer bring a frame into me for resizing that he bought online. It's a polcore/emafyl moulding with a scoop on the back of the moulding, and when I tried trimming it the moulding broke quite badly at the top of the scoop. Any ideas on how I can stop this as I've never worked with any plastic moulding before. I'm using a standard foot operated Morso.

Lucky you for working in beautiful Whitby, great fish 'n' chips. Unlucky you for agreeing to downsize plastic framing, the corners always shatter!
Stand by for an avalanche of responses, mostly to the tune of 'Life's a learning curve'. Beware of the famous "Could you just....." Now over to the experts.

I use a lot of polcore mainly for volume work and find it cuts best on a double head miter saw, if you do manage to sort it be carefull when pinning do not pin at the back of the moulding as this causes it to open up

This comes under the heading of "Yes it does that".

The frames would have been originally cut on a production saw that had been specifically set up to
deal with plastic moulding. v-nailing the corners would have stressed the plastic so if you try to cut
it on a Morso it's likely to fracture if you are shaving the ends.

Cutting down cheap frames may seem perfectly reasonable but as you have just discovered, there are
lots of pitfalls. And who does the customer blame? You or the moulding manufacturer? > <

My advice is don't take on these cheapskate jobs unless you have a gun to your head.

I'm not sure there will be much else you can do.
Maybe try changing the blades so they are as sharp as can be and maybe try just shaving a tiny amount off each time.
If that doesn't work maybe just offer to remake it in a similar wooden frame.

Thanks everyone. It certainly is a learning curve and I'm swinging towards the last idea given of just offering to make a wooden one instead. Lesson learned on this one I think.

Yes, it is a learning curve - I've learnt the hard way. As mentioned above sometimes it's best taking several little shaves off the polcore stuff. And..... not all 'plastics' are created equal - some are better than others.

I've tried to be to good guy in the past and taken jobs that I know aren't worth the hassle but I try to help where I can. The majority of those jobs have come back and bit me on the arse

featurepiece wrote:
I've tried to be to good guy in the past and taken jobs that I know aren't worth the hassle but I try to help where I can. The majority of those jobs have come back and bit me on the arse

"No good turn goes unpunished"

I have my suspicions that molymer mouldings get more difficult to cut after a while, because they get more briitle over time. I can't prove this, but my experiences tend to suggest this. I stopped using polyner mouldings some time ago, even though I particularly like some of the nice finishes that are available on some Polcore mouldings. I wonder how many of us have noticed that some products made from certain plastics become quite brittle with age and then you end up have to buy a replacement for the item that's just broken. This is something which is very common with off the shelf ready made frames, nobody is very surprised when this happens and most people don't care about it, there cheap and people consider them a throw away item. Are we wanting to be part of that same market?

I can easily understand why so many framers like these mouldings, as the discounts available for large quantities are very attractive. I would guess that many of us have at some time been attracted to polymer mouldings and probably for what appeared at the time to be all the right reasons, but as time goes by at least some of us have reverted back to normal mouldings. Probably large volume oriented organisations can really make this pay, but for those of us who have smaller operations, I'm not convinced that the advantages of using polymer moulding are quite so pursuasive. Since the credit cruch came along during 2008, I have noticed an emphasis on offering a greater range of economically price wood mouldings and though I only speaking for my self, I find these easier to work with that polymer mouldings.

So there it is, Whitbyframer, your loss should help other Newbies in the future. The other no-nos are large Ikea cardboard frames 'just' needing tidying up a bit as the sides bow out (and the scratched acrylic following no doubt). Wilko's flimsy glass is another 'cause celebre' for us muggins who never used to say 'No' to just popping in a mount! You have been warned...

He he, all these other guys are of course just pulling your plonker as it were, poly moulding cut really really well on a mitre guilotine, the key is sharpe blades and small cuts to prevent the shatter, we have cut decades old emafyl with ease on tje guilotine, purchased to make spacers for deep items because it was free and therefore cheaper than wooden spacers
So to reiterate fresh sharpe blades, small cuts oh and it helps if your workshop isn't too cold.

How's Whitby today, friend?

IFGL wrote:and it helps if your workshop isn't too cold.

That's true! Folding polymer moulding in an old electric blanket, only one layer above and one layer below, for a while before cutting it on a morso makes a big difference if your workshop is not warm enough. You're not supposed to use electric blankets rolled up, so be careful. Also you will need a warm blanket above and below the electric blanket to allow the heat to build up.

It takes longer than you think to warm polymer mouldings all the way through, so don't be too hasty!

It's white Bobble! Which is very pretty, but is killing business.

Thanks IFGL