Polythene curving inwards on new tunnel

[match]

Hi,

We've just finished applying the polythene to our new tunnel (14x15) and having applied the final tension, the polythene is now curving inwards between the hoops, starting at about shoulder height and running up for a few feet before becoming less pronounced at the apex.

It's nicely under tension, so it's not sagging, but it does mean the plastic is touching some of the inner crop bars, and it doesn't look quite right.

I've emailed the manufacturer to ask about it, but since it's the weekend I thought I'd also ask here to see if anyone else had encountered this, and if it's something we've done wrong/can fix, or nothing to worry about (other than rolling out more hot spot tape!).

Any advice greatly appreciated!

[marchogaeth]

Have you got any pictures, please? I want to be sure I'm visualizing the problem correctly - I suspect I won't be the only one.

[match]

Have you got any pictures, please? I want to be sure I'm visualizing the problem correctly - I suspect I won't be the only one.

I've just gone and tried to take a picture this morning, but my camera really doesn't like the brightness on this unusually sunny Scottish morning!

The best way to describe it is that its the same as if you pushed your finger into a taut piece of polythene so that it bulged out at that point - only the bulge is made by the hoops where they touch the polythene in an arch.

The bit which is strange is that it does this at the sides (and comes in to touch the length-ways crop bars, but not at the top (where there is clearance of 2 inches between the polythene and the crop bar).

The more I look at it the more 'normal' it looks, and I'm probably just being paranoid. I've got some more hot spot tape on back order, and it's not creating any obvious points of excess tension or rubbing, so it should be fine!

[burnie]

What part of Scotland are you match?

[match]

What part of Scotland are you match?

Down in Midlothian... just tried to update my profile but I'm getting access denied (possibly as a new user?)

Been a bit of a lurker on these forums for a while, but not had any questions until now!

[veggiechicken]

Hi match and welcome.
Can't help with the PT but you're right about being a new user so unable to edit your profile and probably you wouldn't be able to post photos either, so we'll just have to imagine it, unless you can add a link to them on a photo hosting site. (I've no idea about those either. )

[lottie dolly]

Hi Match,i would say you are fine,have a look on line at the large poly tunnels for professionals,they dip inbetween the hoops,it's how the poly sheet goes after being made taught,i hope thats all it is,as cannot think of anything else ,welcome to the vine.

[match]

Hi Match,i would say you are fine,have a look on line at the large poly tunnels for professionals,they dip inbetween the hoops,it's how the poly sheet goes after being made taught,i hope thats all it is,as cannot think of anything else ,welcome to the vine.

Ahh! Thanks for that - I've searched some images of larger tunnels, and yes, it looks exactly like what I'm seeing! Thanks for the advice - much more reassured now

https://pbs.twimg.com/media/Dy8nMvdWkAE5WLO.jpg

[lottie dolly]

Phew thank goodness for that,much better than a transforming poly tunnel,all thought now directed at what you going to grow inside it,good luck.

[Vince G]

Here's a pic of mine from the summer. It's a bit far away but you can see mine does the same thing. It's because not only are you stretching the cover lengthways over the hoops, you're also pulling it downwards towards the ground on each side, so there is tension from between the hoops from either side, not only from the ends.