Wednesday, 10 December 2008

Weight built up - slight problem

Dam - worth a try on to plan B



I cleaned up eight of the cast iron weights and gave them a coat of hammerite. After much thinking about ways of connecting them, articulated so I could feed them in pairs into the pockets, I came up with this solution.



A length of stainless steel cable loops through the hole in the top weight down to the second weight. Both ends are clamped using a 12mm bolt with 2 holes drilled through, a washer and nut.

I had to keep the total length, after re-measuring, within 750mm to get full movement of the sashes. I just managed this, but realised I'd have to be really accurate tying it on to the sash cord.

I had calculated the weight of the sashes and set about adding squashed lead pipe to make up the weight. Easy enough to wind around but it took ages to mange to solder tack the spiral together. It was a cold night and iron took the heat away.

Disaster - I checked actual weight of the sashes using bathroom scales and I was short by 2kg on the made-up weights. More procrastination, I couldn't add enough extra weight without either increasing the width, or adding to the length. So it was back to the calculator and Plan B.

I'll use one cast iron weight and one proper (bought) lead weight. So not a total catastrophe as using the iron will reduce the lead I need to buy by half. I also think the ones I've made up will suit one of the slightly narrower window.

I've now ordered the lead and will be picking it up next week.

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