Hello everybody. Any counterindications in using less thick stainless steel plates instead of 5mm aluminium ones?
Cheers
http://www.sperkoengineering.com/html/Rust.pdf
I know it surprising to a lot of people but stainless steel does in fact rust. One of the causes of it rusting can be surface contamination with other iron based items. This is a garden one of the chemicals that can be used when treating crops for mineral deficiencies is “sulphate of iron” yes it also included in some fertiliser mixes, Garden is not exactly the perfect home for stainless steel.
Yes it possible to use thinner stainless steel and get same structural strength as aluminium but in you will have to allow that the stainless steels surface could be pitted in time.
http://www.tibtech.com/conductivity.php
Next is a nastier problem. Most of the frame in current design is aluminium. Note the Thermal expansion coef. from prior link
Aluminium is 23,5 and Stainless steel is 16,5
Then notice Density thinner Stainless steel for same structural strength in some cases can end up heavier. To keep same weight 5mm aluminium would have to be replaced with 1.6666.mm stainless steel and that would not be as structurally strong.
http://www.kastenmarine.com/alumVSsteel.htm
This has the structural strength rough maths between steel and aluminium. For every 1mm of steel equals about 1.5mm of aluminium to provide matching strength. So steel plate the same strength as 5mm thick aluminium is 3.3333.mm thick steel what is basically double the weight of the existing aluminium bits.
Is a 1.6666mm. saving on plate thickness worth doubling the weight of the part and having risk thermal expansion and contraction issues due to everything other than bolts it connect to is aluminium. That is the exact result attempting to swap the 5mm aluminium plate for equal stainless steel in that location.
Jackcoach I don’t think you did the maths or considered the materials around that part there is not enough gain there for me to risk changing it of course nothing forbids you from trying it and crossing you fingers that the pressures from thermal are not problem causes and the extra mass does not come a issue down the track.