BU blades
Bill G
My first comment is, you have enough information for a good book on
sharpening. You have touched on many points the previous books have
overlooked. It would be nice if you had access to an electron
microscope to further your findings.
I was quite impressed with you contribution of BU plane blades. Please
tell me if I fully understand your position.
You are suggesting, when the edge wears, it wears the front and the rear
of the blade. The front is easily re sharpened via a microbevel, very
little material needs to be removed, hence the beauty of a microbevel.
However, on the back side, to remove the wear, you must flatten the
entire back to get remove the wear. Even if you only flatten the last
1/4" of the blade, this is still a tremendous amount of material to
remove, making re sharpening a very tedious process.
Following your suggestion, if you put a 3 deg. micro bevel on the rear
of the blade, you now have a means to to quickly hone the wear out of
both sides, with very min. metal removal, speeding up the honing
process, producing a sharper edge and greatly extending the life of the
edge.
Is this right? If so, I have a few questions:
1) This same theory applies to both BD and BU planes, right? I don't
see any difference here.
2) By adding a backside micro bevel, you have changed the over all
cutting angle. But to compensate, you an just as easily change the
primary bevel if you want to maintain certain "net" cutting angles?
3) This same general principle applies to all edges. The only
exception might be a chisel, whereas the approach of the is sometimes
used with the flat back of the chisel running flat into the cut, in
which case you should avoid a back micro bevel?
Thanks
Bill
Brent
Glad the site was helpful to you. Some answers to your questions
On Aug 18, 10:53 am, Bill G <bgl...@rconnects.com> wrote:
> Brent, great web site, great contributions, thank you...
>
> My first comment is, you have enough information for a good book on
> sharpening. You have touched on many points the previous books have
> overlooked. It would be nice if you had access to an electron
> microscope to further your findings.
> I was quite impressed with you contribution of BU plane blades. Please
> tell me if I fully understand your position.
>
> You are suggesting, when the edge wears, it wears the front and the rear
> of the blade. The front is easily re sharpened via a microbevel, very
> little material needs to be removed, hence the beauty of a microbevel.
> However, on the back side, to remove the wear, you must flatten the
> entire back to get remove the wear. Even if you only flatten the last
> 1/4" of the blade, this is still a tremendous amount of material to
> remove, making re sharpening a very tedious process.
>
> Following your suggestion, if you put a 3 deg. micro bevel on the rear
> of the blade, you now have a means to to quickly hone the wear out of
> both sides, with very min. metal removal, speeding up the honing
> process, producing a sharper edge and greatly extending the life of the
> edge.
>
> Is this right? If so, I have a few questions:
>
> 1) This same theory applies to both BD and BU planes, right? I don't
> see any difference here.
bevel down blade, leaving the back wear bevel in place increases the
cutting angle. Not good for soft stringy woods, may even help for hard
woods. So, usually it is not a problem.
With a bevel up blade, leaving the wear bevel on the back eliminates
the clearance the blade needs. The blade surfs the wood rather than
penetrating it. People often have great results with the new blade,
then the results get worse and are not improved by a typical
sharpening.
> 2) By adding a backside micro bevel, you have changed the over all
> cutting angle. But to compensate, you an just as easily change the
> primary bevel if you want to maintain certain "net" cutting angles?
the front angle if you were worried about it. Adding the back micro
bevel ensures you continue to have the necessary clearance.
> 3) This same general principle applies to all edges. The only
> exception might be a chisel, whereas the approach of the is sometimes
> used with the flat back of the chisel running flat into the cut, in
> which case you should avoid a back micro bevel?
guide (paring, back on the work) would be a problem. If you can work
with the back 3 degrees off the work, then a back bevel is no problem.
Thus, carving and turning chisels have no problem. Even bench chisels
used bevel down have no problem. I have not looked into the shape of
the front and back wear bevels on bench chisels.
The thought of using a chisel enough to get it dull through back down
paring operations alone (the only way to know if it even gets a back
wear bevel) is not daunting. Plane irons get upper and lower wear
bevels because of the way they are used. The forces involved are much
greater than those encountered during paring.
Anyone have any idea about the shape of the wear bevels on a chisel
used only for back down paring?
> Thanks
> Bill
Brent
Bill G
> You don't happen to have one, do you?
>
No, unfortunately...... my only point was, it seems
a lot of the answers lie in seeing the outcome of your experiments, vs.
testing them with wood.
> With a bevel up blade, leaving the wear bevel on the back eliminates
> the clearance the blade needs. The blade surfs the wood rather than
> penetrating it. People often have great results with the new blade,
> then the results get worse and are not improved by a typical
> sharpening.
>
EXCELLENT, so true..... I have often
good luck with a new blade, then in due time, sharpening it never
returns it completely to its original state. I am quite surprised LV
or LN has not caught on to this....and market an easy to use jig, that
switchs between back and front microbevels.... hard to believe they
could over look this....once I read your site, it become so obvious...
>
>
> Having a large back bevel on a chisel which is used with the back as a
> guide (paring, back on the work) would be a problem. If you can work
> with the back 3 degrees off the work, then a back bevel is no problem.
> Thus, carving and turning chisels have no problem. Even bench chisels
> used bevel down have no problem. I have not looked into the shape of
> the front and back wear bevels on bench chisels.
>
Yes, this is what I suspected, thank you...
> The thought of using a chisel enough to get it dull through back down
> paring operations alone (the only way to know if it even gets a back
> wear bevel) is not daunting. Plane irons get upper and lower wear
> bevels because of the way they are used. The forces involved are much
> greater than those encountered during paring.
>
Agreed, i was more curious than
anything...... the plane blades rear bevel is the breakthrough for
me.... I like your verbiage, the edge will "surf" the wood, vs.
dragging on the wood... a very descriptive word for this enhancement.
Also, I am curious of your opinion...I
have read, that after 8k, water stones will not make blades noticeably
sharper. However, after buying a 15k Shapton, then a 30k Shapton, I
disagree with this..... each step up in fineness creates a sharper
edge...would you agree with this? I also have experimented with 1/4
micron diamond paste, and it also takes me to a higher level vs. the 30k
stone.....
You mention the how Stanley really
uses the right metal in their plane irons (I don't recall the name of
it). I am curious, why do you think the other big makers like LV LN
have not used the same? It seems much superior to A2 and O2 which have
become industry standards?
Bill
Brent Beach
Bill G wrote:
> Agreed, i was more curious than
> anything...... the plane blades rear bevel is the breakthrough for
> me.... I like your verbiage, the edge will "surf" the wood, vs.
> dragging on the wood... a very descriptive word for this enhancement.
? verbiage ... and here I though I was being succinct.
> Also, I am curious of your opinion...I
> have read, that after 8k, water stones will not make blades noticeably
> sharper. However, after buying a 15k Shapton, then a 30k Shapton, I
> disagree with this..... each step up in fineness creates a sharper
> edge...would you agree with this? I also have experimented with 1/4
> micron diamond paste, and it also takes me to a higher level vs. the 30k
> stone.....
Are you using a jig?
I have not tried Shapton stones, so I don't know how they compare to the
3M abrasives. If Shapton were willing to be compared they would rate
their stones in Microns. When each manufacturer uses their own grit
system comparison is impossible. I may have access to some Shapton
stones in the next couple of months. If I do, I will get some images of
the scratches left by the various grits.
I am not sure of the exact rules for the various grit size designations,
but each specifies both an average size and a distribution of sizes
around the average. If you use the micron sizing, the distribution is
supposed to be pretty close to the average. Other standards have looser
rules. When you have your own grit system, you can do what you want. I
vaguely recall that Japanese water stones have a wider range of grit
sizes that other abrasives.
Flatness of the abrasive may be affecting your edges at lower grits. I
understand the higher grit shaptons are much harder, must less likely to
be out of flat. That may be what you are benefiting from.
> You mention the how Stanley really
> uses the right metal in their plane irons (I don't recall the name of
> it). I am curious, why do you think the other big makers like LV LN
> have not used the same? It seems much superior to A2 and O2 which have
> become industry standards?
Are you referring the the High Speed Steel blades made in Australia? I
don't think this was originally an official Stanley product. It may have
originated in the Hobart, Tasmania plant. Some Australian woods are
extremely abrasive. This may have been the locals making a blade that
would handle the woods. I have also heard they used these blades to
plane fibre glass on their boats.
The HSS blades were eventually sold under the Stanley brand around
Australia. Their success would have been limited by the difficulty in
sharpening the harder blades - many hobbiests may have been unable to
sharpen the blades with their oil stones.
Australia produces HSS blades today - although I don't think Stanley
does. Both Academy Saw Works and the plane maker HNT Gordon sell HSS
blades. And, of course, Mujingfang from Hong Kong for some of their planes.
Brent
> Bill
>
>
>
>
>
>
>
>
>
>
>> Anyone have any idea about the shape of the wear bevels on a chisel
>> used only for back down paring?
>>
>>
>>> Thanks
>>> Bill
>>>
>> Brent
>>
>
> >
>
--
Victoria, B.C., Canada
Bill G
>> I also have experimented with 1/4
>> micron diamond paste, and it also takes me to a higher level vs. the 30k
>> stone.....
>>
>> Are you using a jig?
>>
You bet I do..... V MKII my main weapon
> I have not tried Shapton stones, so I don't know how they compare to the
> 3M abrasives. If Shapton were willing to be compared they would rate
> their stones in Microns. When each manufacturer uses their own grit
> system comparison is impossible. I may have access to some Shapton
> stones in the next couple of months. If I do, I will get some images of
> the scratches left by the various grits.
>
That would be great...
> I am not sure of the exact rules for the various grit size designations,
> but each specifies both an average size and a distribution of sizes
> around the average. If you use the micron sizing, the distribution is
> supposed to be pretty close to the average. Other standards have looser
> rules. When you have your own grit system, you can do what you want. I
> vaguely recall that Japanese water stones have a wider range of grit
> sizes that other abrasives.
>
I used to read up on this....and what I learned
was....up to about 5k in grits, everyones scales are about
equal....after that, the results are all over the map in how they are
rated... so its a hornets nest trying to follow the nominal grit
numbers.... all you can be assured of is... if you use the same maker,
like Shapton, their higher numbers are finer than their lower
numbers....but once you start trying to compare between vendors,
anything goes....specially between different types of grits, such as
diamond paste vs. water stones, vs. sand paper, etc. This is where a
high powered microscope would really be beneficial..
>
> The HSS blades were eventually sold under the Stanley brand around
> Australia. Their success would have been limited by the difficulty in
> sharpening the harder blades - many hobbiests may have been unable to
> sharpen the blades with their oil stones.
>
OK, this explains the shortcoming of that
better metal..... like everything else, its always balancing the
trade-offs, and in the end, it seems like 02 and A2 were the big
winners...probably a mix of edge sharpness, ease of sharpening and
longevity....although your tests revealed the blades dull much faster
than one would suspect, and I fully agree with you.... every 100
strokes on avg, I find a quick honing is in order..... of course, its
not mandatory, it just makes the experience more enjoyable...
> Australia produces HSS blades today - although I don't think Stanley
> does. Both Academy Saw Works and the plane maker HNT Gordon sell HSS
> blades. And, of course, Mujingfang from Hong Kong for some of their planes.
>
Understood.....but if this metal was so
superior, I think LV and LN would have used it... in addition to what I
mentioned above, maybe the metal is hard to produce?