The SI - Alvu window lock gear box is available in either a 20mm or 22mm backset, which is the measurement from the edge of the cam to the centre of the follower. These sizes are also stamped on the gearbox themselves, which can hopefully allow you to indentify as to whether this is the model you need. The fixing centres for the Si-Alvu UPVC window lock gear box is a standard 42mm and accepts a 7mm handle spindle.
These models of window lock gear box have been designed and manufactured by SI, they can also be known as Alvu UPVC window lock gear boxes.
The gearboxes themselves are usually one of the first components to break; this is due to them being under the majority of the stress as they have to deal with the locking, unlocking, opening and closing of the window.
This model is identifiable by the stamp mark, SI, which can be found near one of the fixing points.
Additionally this model does have "L" and "R" stamped onto opposing sides of the gearbox.
Hi guys. My name is Darrel, and I'm head of the tech team here at LocksOnline.co.uk Thanks for taking some time to tune in and have a look at one of our product review videos.
The products that we have here in front of us today is a range of gearboxes that's manufactured by a company called SI. They're designed for window locks, UPVC multi-point window locks. They also may be known as Alvu many, many, many years ago.
One of the key idents that make you think whether or not this is the actual gearbox for you, it actually has stamped here on the covers that actually cover the extensions there. It has actually SI stamped on there, if you can zoom in close enough to actually see that. It's a bit touch and go. That's what you want to be looking for, and if it's got SI stamped on that, then you're on the right track for choosing the right particular product.
Now, they come in two different sizes. They either come in a backset that is either 22 millimetres or 20 millimetres. This particular one here is 20 millimetres, because it actually has 20 stamped on there, it's as simple as that. So if you actually open it up and you find the number 20 on that, then you know you've got the 20-millimetre version, and if you actually got the one here which has got 22 stamped on it, then you'd know you've got the 22-millimetre version. This is quite straight forward as that.
Now, normally with these particular types of gearboxes, the reason why we talk about the gearbox more so than the actual parts that come out here and shoot the bolts into either end, is it's the gearbox that's taken the majority of the weight when you go lifting the handle to lock your window and unlock your window. It's this particular part that normally fails. Not necessarily the bars, normally the bars just need a bit of oil, a bit of lubrication, a bit of cleaning up. Inside here, if the mechanism fails a little bit, then you're in a bit of trouble there.
So this is the reason why we're looking at the gearboxes in particular, but we can also get all of the bars and the extensions. Just pop a call over and we can sort you out with those. That's no problem at all.
Some other key notes to mention as well is that the centres here is standard from the screw fixings of 42 millimetres. That's pretty standard in the industry, and also the follower here is pretty standard as well at seven millimetres. I got a handle here, and as you can see that fits in there nice and sweet, and then would operate the handle as per normal. All right. So that's how that actually works and gets put together.
So there you go guys. Some of the other little indents as well that you'll see here. You have the letter R stamped on there, and you also have the letter R stamped on there. Also on the other side you have L, and similar on this side as well, you've got L as well.
So there you go. It's the SI range of gearboxes that are available on our website. If there's any more information that you think that you may need, or you're not sure on a measurement or you want a little bit more of advice, listen pop us over a call. We'd love to hear from you. Use our live chat on our website. That's totally free. Or just pop us over and email in the evening at your leisure.
Either way, we'd love to hear from you, and more importantly, we'd love to see you as a customer. So from me, Darrel, and all of us here at the LocksOnline team, thanks for tuning in and we'll catch up with you real soon. Take care now. Bye-bye.