Dealing with the 25mm/1" discrepancy

[mr henderson]

The book assumes the chassis to be mainly constructed with 25mm square tube, but I daresay many of us are using the more common 1" square tube, which is approximately 25.5mm square.

This means that some of the finished dimensions will be out, for instance, if the main cross pieces BR11 and BR12 are cut to 1068 as in the book, then the overall width of the chassis will be 1068 plus 50 if using metric steel, and 1068 plus 51 if using imperial (1" sq), so 1mm wider.

Just wondering what those who have already constructed chassis using 1" sq have done about this? My inclination is to ignore it and stick to the book lengths, as long as everything is square I can't see an extra 1mm being a problem, but I'm always interested to know of other people's experiences.

[Peter-C]

I asked this question on the original forum because I had a mixture of 1" and 25mm and I just compensated for it by adjusting very slightly to give the same overall dimensions as the book. Mr Gibbs replied and said that would be fine.

If you use a mix of imp and metric then compensate by doing outer rails first then cut the inside jobbies to suit...i would eerrr on being tad shorter too if the chassis grows grp panels won't fit.....be warned.

I remember a few years ago a chassis I was shown that was made by a name known to quite a few in the kit world....ummmm the word pants springs to mind it was longer one side than the other and had longer wheelbase one side to the other...oh and it was brand new never turned wheel as hadn't been fully built.

Scary bit was the mad tuned motor that was going to live in it....beats me it really does how firms turn out such shite.

Another I saw designed for the pinto had been fitted with a mad tuned V8 and surprise surprise the chassis was twisted after only a few track days.. These cars aren't designed for giddy horespower and same goes for our crap roads so why do folk bother...?