GoodSoundClub - Romy the Cat's Audio Site

In the Forum: Horn-Loaded Speakers
In the Thread: Rakeshorns

Post Subject: LVFrame strength: Never mind Russell Crowe, Russ himself can swing off these with easePosted by oxric on: 12/7/2011

oxric wrote:
Hi Romy,

First of all, as things stand in the sketch, the mast sits atop the legs, a horribly precarious position given the weight that will be applied away from the centre of mass of the structure. This sketch is an early one, just to give an idea of overall appearance, and I should not really have posted it given the weakness that would be inherent to that design, as you quite correctly point out.

The mast will in fact sink in between the two legs (the point of the cut-outs near the base of the mast) and it goes without saying that Russ will do what's necessary to strengthen the mast in the vertical plane. I have told Russ to make the mast firmly fixed enough to hold a total weight of 200kg at a distance of 50-80cm away from the centre of mass. I like the bracing that you make use of in your frame and if Russ feels it is necessary or helpful, I would be very happy to have these fitted to my frame. Thanks for the suggestion.

This frame cannot be weak and it will not be weak. If it is, I will make a lovely bonfire out of the whole thing without a moment's hesitation and the closest it will get to my place in France will be the smell of the croissant I will toast on it as it burns merrily away in my back garden here in the UK! I have two little ones. Their safety is of paramount importance and comes before any stupid audio project of mine.

Best regards
Rakesh

Even after writing the above, I will confess to a slight doubt creeping in my mind following Romy's suggestion that the frame might be too weak as I sort of agreed that on paper it could appear that without some strengthening plate as he suggested the frame could not support the mast as this would in turn be supporting some heavy loads acting away from the centre of mass of the structure. So I told Russ that a requirement for me was that a grown-up adult male, say Russell Crowe, in full battle suit as in the opening scene of 'Gladiator' the movie, should be able to swing off a rod attached in the uppermost hole in the mast at a distance of 1m from the mast.

So that exactly what Russ did, except that Russell Crowe having chickened out at the last moment, it behoved to Russ the brave creator pf my LVframe himself to bravely and selflessly offer himself to the experiment borne from my sick imagination. Here is what he had to say on coming out of this experiment with all limbs intact (e-mail slightly edited for reasons having to do with the relevant patents, intellectual property and copyright laws that protect all work that issue from Russ' legendary workshop):

Hi Rakesh...

I did a quick test of the strength of the stands this morning, I happen to have a 28mm diameter iron bar in the workshop so i used this in the top hole and supported my weight (65kg) at a distance of 1m from the mast (practically above the end of the legs) and there is absolutely no movement whatsoever! even by bouncing around the only movement is the iron bar bending and slight wobble as a result of my uneven workshop floor! so yes you could say it is strong enough! and there will be no need for mandatory safety helmets in the living room.

Russ.

For those who are more conversant with the arts of woodworking, I hereby unveil the ingenious system devised by Russ to support the mast and horns above which obviated the need for a supporting steel plate.

Best regards
Rakesh

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