knowing it is sharp

[engineerone]

colin cott was kind enough to drop in last night, and check out a couple of things for me.

one thing that concerned me was that i was not sure that all my planes were as sharp as they should be. but how do you know if you do not have the experience. so colin kindly checked them out.

all 8

so the concensus was that a couple were ok, but some of the others were sharp, but not "SHARP" it was only in a couple areas, and that is i think the problem for many who are just starting out with hand tools again. you just have no standard for judging sharpness.

on a couple of the planes i had not completely got rid of wire edge all over the blade. on another i had some how rounded over the back.

so anyway i must thank him again, and commend all of you amateurs to make friends with someone locally who can give you a sounding board to enhance your skill and ability.

paul

[dunbarhamlin]

Good advice, if there's someone on hand. I went on a course recently, before which I thought my tools were sharp, but soon learnt otherwise.
I now work on the principle that even if I haven't noticed (and now I've seen the difference, I usually do), if I've been using a tool for five minutes or so, it is due for a touch up - honing free hand makes this hassle free.
Cheers
Steve

[davidc]

Higher probability of correctly honing away wire edge, on plane blades, is one of the valuable features of the ruler trick.

Your comments are very aposite. One cannot judge sharpness well without being shown it and feeling how it cuts.

David

[engineerone]

nice to see you back here again DC.

what is really interesting is that i was getting nice thin shavings, but it just felt that i was putting too much effort into it

which is why i asked for the help of colin

next time though when i get a new blade to work with, i can use the ruler trick, and see how much easier it makes the task.

paul

[David Charlesworth]

Paul,

The main thing is that you got some good help. Working in isolation is difficult.

I find it takes a while for my students to recognise the signs which indicate that a resharpening is in order.

Even the highest quality blades loose that wonderful singing sharpness after a few minutes of continuous use, in dense hardwoods.
I like to say that the merest suspicon of loss of performance, signals time to resharpen. The resulting improvement and lessening of effort will always reward us.

David

[paulchapman]

David said:

that wonderful singing sharpness

Apart from the fact that it cuts better, the singing sound that a blade makes when it is truly sharp is one of the best indications that you've got your honing right. The other is to look at the edge under a good light. When a blade gets blunt, the edge becomes rounded over. It's easy to remove the roundness from the bevel side and to get a burr, but this doesn't always mean that the roundness on the flat side of the blade has been fully removed. I think that's often the difference between sharp and really sharp.

Cheers

Paul

[mrgrimsdale]

The nearest I get to super sharpness (as far as I know!) is by rapid alternation between honing on the bevel and the flat - quick dab on the bevel side, quick rub on the flat, each time a smaller burr getting turned/removed. A little and often.

cheers
Jacob

[engineerone]

gawd, every time i get to be a little happy about my new skill, you guys come along and burst my balloon ;D

i think the thing that is even more scary than sharpening, is
getting the skill to disassemble the plane, sharpen and hone, then re assemble, and re-set at the same place so you get the fine shavings again

that too is an interesting art


paul

[David C]

Yes, there is a lot to practice and learn.

For setting, I use a mild scrap board about 15" long and 3/4" thick.

When you think lateral is good, (use a shim), retract the blade completely.

Then take full length test shavings from the edge, as you advance the blade, very patiently a few 'minutes on the clock' at a time.

This way you won't get a nasty shock when you return to your planing.

best wishes,
David

[engineerone]

thanks again david.

i knew i should not have stopped to talk to you at the last axminster show ;D in all that excitement, i thought the next stage
would be fun as well as interesting.

but all that work

actually however i do enjoy it, although i can see why so many pros use machinery.

thank gawd i cannot use a power planer ;D

paul

[modernist]

One thing I did not initially "twig" was that having once used the "ruler trick" you have to use it forever in order to remove the burr.

[modernist]

I find a well tuned pair of Levi's is also particularly good at removing the burr. I've managed to avoid an involuntary vasectomy so far ;D ;D

[pam]

engineerone said:

...actually however i do enjoy it, although i can see why so many pros use machinery...

You probably think those planer and jointer knives sharpen themselves?

Pam

[engineerone]

no pam i do not think they sharpen themselves, and having a mafell 160, i know about removing them, honing, and replacing.

however, most pros leave sharpening of planer/thicknesser blades to an outside supplier, rather than do it all themselves.

paul

[Scrit]

engineerone said:

However, most pros leave sharpening of planer/thicknesser blades to an outside supplier, rather than do it all themselves.

The bigger shops often have a dedicated planer blade grinding machine (they rarely get honed as such), but at over £1k for a decent machine you need to be a serious throughput shop to afford it. For smaller shops it's simply a matter of time - easier and quicker to let the saw shop do it than DIY. After all time is money. One thing yoyu can do yourself is to back hone (i.e. hone a face bevel) of 5 degrees on your planer knives if you are ever faced with something truly awkward to machine plane - like birds eye maple. That and a damp sponge can work wonders.

Hand tools, however, are a different matter.

Scrit

[engineerone]

obviously i did not want this to descend into a hand tools against power debate. however it is important to consider what you do.

time is money, but the hand tool guy costs his time in a different way from the power tool shop.

no less valuable, just different.

paul

[davidc]

Scrit,

The machine back bevel is a wonderful thing, and has direct relationship with back bevels in conventional hand planes.

On my nice old fashioned planers, I could hone the knives in situ and keep them going for months.

Modernist,

The ruler trick is a way of life, not just for christmas ~;-)#

Though it would not take that much effort to remove the miniscule (2/3 degree back bevel) if you put it on with a Japanese polishing stone of 6,000. 8,000, or 10,000 grit as suggested in the destructions....

best wishes,
David

[mrgrimsdale]

Hmm. Well as it happens I'm planing up some 10" sycamore boards for a table top and they are heavily figured (in a rough hedgerow sort of way) and the cross grainy bits rip out in chunks. I'd decided not to risk planer experiments or I might lose too much thickness, and was resigned to some hours of belt sanding. I might try again with the back bevel trick.
I put some nice newly sharpened blades on but they were worse than the blunt ones for ripping out cross grain, praps the part worn ones are already back bevelled a touch and are scraping instead of cutting?
I'll report back!

cheers
Jacob

[pam]

Jacob, have you tried a toothed blade?

Pam

[mrgrimsdale]

pam said:

Jacob, have you tried a toothed blade?

Pam

Er, no. How would that work? I've never heard of it. Not a leg pull by any chance?
Though come to think I've noticed that the circular saw doesn't do the damage to an edge that the planer will do, so saw finished edges followed by sanding or scraping works, but not saw finished faces (not a big enough saw). Would a toothed planer blade remove material without rip out, leaving finishing off as another problem?

cheers
Jacob

[pam]

Well, I don't want to make any promises, but often a toothed blade (I have a coffin and LN LA Jack with toothed blades) will allow you to hog off difficult grain. You'd then follow it with a finely set smoother.

Pam

[engineerone]

blimey jacob, even i had heard of a toother blade for planes.

you really must take the blinkers off sometimes and look around and smell the roses. as you keep saying very little is new, and toother blades are i think rather like ridged soles for planes another attempt to make up for the basic shortcomings.

neither lv nor ln are claiming to re invent the wheel, rather to improve the quality, and add modern benefits.

like many people coming back late to the interest, i did not have much in the way of old kit that i had learnt on in my youth, so i went the quick and dirty route and bought brand new with quality as my guideline. as i have said many times before, now i know what my baseline should be, so can make objective and informed decisions about the future direction. without the knowledge, i cannot know for sure.

whether you want to spend the money in cold hard cash, for one of the "top three", or take time which equates to money, and also spend some money fettling old things, getting quality and a decent baseline always costs money.

but if you don't know what the baseline is, you are wasting time and money by fettling something old if you have nothing or no-one who will show you where you are and where you are going.

paul

[mrgrimsdale]

engineerone said:

blimey jacob, even i had heard of a toother blade for planes.

Thats praps cos you read a lot of catalogues ;D ;D and i bet you've bought one, need it or not
No it's not something I was aware of and doesn't seem to get mentioned in the books except that toothed plane/scraper for veneering. Anyway i was talking abt planer machine, I'm not doing a 30x72" table top by hand I haven't got the time
cheers
Jacob

[nickw]

You've got a 30" planer?

[mrgrimsdale]

4 planks at the mo ;D