Diesel tank access port question

[Pub911]

Any suggestions on the most idiot(me)-proof way to cut an 8" diameter round hole in my aluminium diesel tank?

Any one ever hear of or use these guys?
http://www.seabuilt.com/index.php

or have a cheaper or better alternative?

Thanks!

[camaraderie]

The instructions for drilling the holes are here:
http://www.seabuilt.com/_pdfs/Instructions.pdf

Looks like a good product. Make sure there are no baffles internal below the cutout!!

Google hole saws for lots of options:

[Pub911]

Great! Thanks. Nice reference manterials. Do you know if they make an 8" diameter hole-saw?....or is that a jig-saw operation only?

[artbyjody]

If your tank has a internal fuel gauge / sending unit - you should be able to remove it - and use one of those telescoping mirrors to look into the tank. One thing to note that, cutting out an inspection hole - you want to make sure the tank is bone dry and allowed to air out (ie- by removing the fuel gauge / sending unit.) so that all the vapors escape.

Also, be wary of what this does for Survey purposes - tanks are tested to meet certain pressure requirements and depending - a surveyor could flag the new addition as not into specs for the particular tank (hardly unlikely but it is possible especially if it is apparent it is a DIY jobby).

[camaraderie]

Pub...here ya go for big holes...not cheap but lots of other uses!
http://www.amazon.com/gp/product/B00...BR4XRSA8CVAPMH