Can't get glazing bars into a new UPVC window

[davphi338]

Hi,

I am trying to install the glazing into a new UPVC window but I can't get the glazing bars in. I've tried hitting the corners with a plastic mallet and holding a piece of wood against it so as not to damage the plastic but it just won't click in.

Is there any special technique or knack. I don't think they can be the easiest to install because the professional fitters who did the rest of the house actaully cracked a couple on the corners.

Any advice much appreciated.

 

[Richard C]

Install the shortest beads first, engage the front of the trim & start at one end working towards the other. Then install the longest beads, bend it in the centre & locate each corner, again, engaging the front of the trim & then work towards the centre; very small windows can be a bit of a pig & I’ve been known to notch the back of the trim in the centre to allow it to bend enough to get it in but you have to watch it doesn’t kink.

The knack is to be brave but not stupid ; engage the front of the trim & you need to hit the back hard enough to engage it but not so hard that you break the glass; I’ve never managed that. A hardwood block is good to protect the trim but not too long as you need to concentrate the force of the hammer blows or the trim wont click in; I also use a steel hammer Not sure about those professional fitters of yours though!

 

[davphi338]

Thanks for the reply, had a bit of a disaster today. Installed one unit all Ok. Got the corner done on the second unit and worked all the way to the other corner, gave it a tap and 'CRACK' the unit failed on the corner. Unfortunatley for me it was the larger unit at 1350x930. I didn't hit the beading any harder then the rest. All I can think is that there is quite a big gap around the glazing when it is sat in the frame. I sat it on 5mm spacers but there was still quite a large gap at the top so I presume I was too close to the edge of the glass at the top.

Anyone know the cost of a replacement unit 1350x950, low E, argon filled, warm edge spacer? I'll soon find out tomorrow when i ring the glaziers. Next time I'm going to pack the bottom more then 5mm.

 

[masona]

I think you'll find the glazing bar is slightly too long, trim it back a bit should make a difference but not too much!

 

[xerxes]

I think you'll find the glazing bar is slightly too long, trim it back a bit should make a difference but not too much!

Are you sure that's right? Surely the bead is usually preinstalled in the window (without the glazing unit) so you can see that it's the correct length, and that the mitres meet properly.

I find that tilting the bead to make a small contact area at one end helps. If it doesn't start making an entry into the channel, I take a look to check that the tang of the bead is angled so as to go into the channel, as opposed to behind or in front of it. Otherwise you can hit it as hard as you like without getting anywhere. Once the bead starts going into place, the rest should be easy.

I use a Wiha plastic mallet which has square heads and seems just right for the job. However, I'm sure a steel hammer is OK, as long as you swing it in the right direction.

 

[masona]

I think you'll find the glazing bar is slightly too long, trim it back a bit should make a difference but not too much!

Are you sure that's right? Surely the bead is usually preinstalled in the window (without the glazing unit) so you can see that it's the correct length, and that the mitres meet properly.

Yes, there are sometime 2mm too long and what happened is when you bang the beading in the corner of the mitre put pressure on the DG unit therefore can shattered the glass, I have done it myself so now I always check it's the correct length because some DG companies do not put the beadings in the windows so not tested, they just sellotape the beadings together instead assuming they are the right length

 

[HandyHands]

Is there a rubber gasket on the frame? It sounds like there is too much pressure on the glass - too thick for the frame.

 

[johnbodger]

Firstly, I would always glaze tiny window panes BEFORE I instthe frame.
The two shorter beads can easily be hammered into place, but the two longer beads HAVE to be bent to fit them, no matter how small they are. So when they will not bend, make a series of small cuts into the tongue of the bead with a junior hacksaw, being careful not to cut into the bead itself, then try pushing one corner into place and bending it until you can push the other end in. If it still won't bend cut 3 "v"-shaped notches out of the tongue a quarter, a half & 3 quarters of the way along and try again. And if it STILL won't bend, make a further 4 notches at eighth way along intervals. Then you will be able to bend it enough to get the ends in. And once they're in - hammer into place towards the middle. Job done!
Good luck!