- Tue Oct 23, 2012 8:54 am
#18777
A-hem... Just to play "the devil's attourney" here for a moment (the one that tries to find the problems and downsides of everything): .-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
An open ended spanner will transfer the force to the bolt head in just two points on the very corners of the hexagon. The risk of rounding it off is big. A properly shaped ring spanner will transfer the force to six points on the sides of the hexagon, very much reducing the risk of destroying something. .-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
About the "Metrinch" spanners: Metric spanners come in 8, 9, 10 mm etc. etc. "Inch spanners" (Imperial?) come in multiples of 1/16" or 1/8". Whitworth is yet another story, measured by the bolts, not the heads. Point is: None of these spanners are interchangeable. What Metrinch has done is they have mad spanners that ALMOST fit the mm and inch spanners closest together, i.e. 3/8" and 10 mm. ALMOST, but not completely, as 3/8" is 9,53 mm, not 10 mm etc. What you need to loosen a very stubborn bolt without destroying it is a spanner that fits EXACTLY. That is not Metrinch! I regards those as "emergency tools" for situations where you can't bring all the proper tools. .-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
About the "Super grip" that Leon Novello mentions: I have one of those, bought more than 25 years ago when I knew a lot less about tools and macines. I think I have found it close to useful ONCE. Normally it will not fit. The bolt heads are most often not "high" enough (maybe "thick" is a better word?) for that one to get a complete grip, so all it does if you put force on it is slip off and ruin the head. That especially applies to soft bolts like brass filler plugs etc. I would NOT use that one on a stubborn filler plug! .-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
There is really only one way to go here: Get the correct tool! Frank is onto it: Get a good 18 mm ring spanner. Fit that onto the plug, give the other end a blow with a suitable mallet. That will normally do the trick. If not, try heating the area around it with a heat gun, then try again. Don't use too much force or heat! .-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
Regards, Anders F. R.