Hi,
Some days ago, I bought a Clifton 60mm spare blade, for a Clifton 5 1/2 that I already own and that I use for long sessions planing rough stock. When I checked if it mated with the chipbreaker, I noticed some light passing through one corner. With the screw tightened I have 0.07mm (3thou) on the high corner. I attached some images below.
I checked the flatness of the whole blade face on a reference surface and I noticed a twist. If I just lay it on the surface I can slide over 0.15mm (6thou) feeler gauge underneath the high corner. If I push on the diagonally opposite corner on the back of the blade I can slide 0.40mm so I would say that there is aroud 0.15 to 0.20mm of average twist between a corner and the diagonally opposite corner (like a twisted lumber to give you an idea).
The blade I already have is not twisted and mates perfectly with the chipbreaker.
My first idea was to grind on a coarse sandpaper (on a float glass or whatever) the hole face to get rid of that 0.20mm of material in the middle (honestly I don't know how much would it take and usually with a convex surface is really difficult because I'll be rocking on a bump and I may get the things worst). Then I was thinking about smithing the blade a bit with a hammer, even if I don't have the skills and experience to do that. I still haven't done anything anyway.
I called Clifton for a technical suggestion and they told me to give it a try first because the lever cap may press the chipbreaker on the blade and flatten that twist. And they also told me that a very perfectly flat blade
is less likely to be found, even if they are stress relieved.
I still didn't try it because, honestly, I'm afraid to copy the twist to the chipbreaker, but maybe this is
more a fear do to both inexperience and obsessive nature.
To be honest, the idea that the lever cap pushes the blade and chipbreaker together on the flat frog
making them mate works in my mind, also because it happens with a Stanley no.11 that I use as a
scrub and that has little twisted irons in it, but works like a charm.
What do you think of the subject?
Thanks,
Haitham, Rome
0.15 gap.jpg
0.40 gap.jpg
w chipbreaker.jpg
original blade.jpg