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View Full Version : Best Way to Rough New Bevel on Plane Blade?



Steve H Graham
06-18-2015, 8:12 PM
I snapped up a #5 plane on Ebay, and it arrived today. I had no problems touching up the blade, but I could tell before I put it back in the plane that the bevel had been ground crooked. Whoever did it created an edge that was at an angle to the sides of the blade. I figured I could straighten it using the lever, but it was so far out of whack it didn't really work.

I created new bevel using a belt grinder and stones, and now it's fine, but it took approximately a century. Okay; 90 minutes. I am wondering what's the best way to do the rough work on a bevel that's at an angle. The bench grinder seems to bite the snot out of it every time I touch it. The belt grinder is a lot better, but still has the potential to create problems pretty quickly.

Should I just go out and get a big carborundum whetstone? Maybe a coarser DMT diamond stone is the answer.

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Dave Parkis
06-18-2015, 9:17 PM
I use a square and a Sharpie to draw a line on the back and then take light passes on a slow speed bench grinder. Its faster on a "regular" bench grinder, but I'd keep a glass of water nearby and quench it every few seconds. The key (IMHO) is to take a lot of light passes rather than trying to get it all at once. Once I get the blade back to square, I take it to some 80/120 grit sand paper to create the new bevel and then just work it through the stones. HTH

Kyle DuPont
06-18-2015, 10:21 PM
I have just started using my low speed grinder to establish primary bevels. I practiced on a cheap chisel to get it right and get the feel. I did burn it once, but ground past that in successive practice. I burned the tool by trying too long of a pass in an attempt to remove a lot of material. I moved my quench water closer to the tool rest and that made it much safer. I also started taking easier passes to reduce heat.

I just have cheap white friable wheels on my grinder right now, but will upgrade to the blue Norton 3X wheels as needed. I have been practicing on the 60 grit wheel.

John Kananis
06-19-2015, 1:11 AM
I've lurked within (and enjoyed) this forum long enough that I figure I should eventually make a first post...

The grinder is the best (slower the speed the better). IMHO, most people use this tool incorrectly; if you need water at your grinding station, you're doing it wrong. Some tips:

Forget the fancy (and expensive) wheels out there. Go for as coarse a wheel as possible 36 grit is excellent but no higher that 60 for carbon steel. Use the white wheels for HSS or softer materials. Use a dressing tool (diamond, silicone carbide, etc - don't be afraid to use this tool often, just apply a very light touch and it should last you many dressings) to create a 'crown' on your wheel so that only the very center of the stone can remove any material.

Lets address the tool rest, most are horrendous and should be outright replaced but oftentimes a small piece of hardboard attached to the stock rest polymorphs a meh device to something quite usable. Set your tool-rest at the appropriate angle and lock it in place. As Dave mentions above, draw a line on your blade using a square and a sharpie (or a machinist's dye if you're fortunate enough to have one - I'm not and a sharpie works just fine for this).

Now, the actual grinding: As I said earlier the slower the speed the better but if all you have is a high speed device, no worries, just take even lighter passes. A larger wheel will create less of a 'hollow' than a smaller (not the biggest concern in the world). Work the blade into the wheel slowly never lifting it off the rest and holding it relatively close to the grinding edge (not the rear of the blade). when you see the first tiny 'sparks', stop advancing the blade and remain at this very light pressure while moving the blade left to right and not stopping in any one spot (this part can not be stressed enough - apply only the slightest pressure and do not stop moving unless you disengage the blade from the stone). With your fingers close to the grinding edge while you work, you will feel any heat buildup and can remove the blade before any damage But, there should be no heat buildup, with this method you can grind a long time. On the average plane iron this process should take 3-5 minutes (a very long time to grind a single blade compared to the steel gouging most do in 15-30 seconds).

I hope this was useful to you and best of luck.

Patrick Harper
06-19-2015, 7:10 AM
A good grinder is one of the most important tools you can own. I prefer a full speed 6" grinder with high quality, friable wheels.

Pat Barry
06-19-2015, 7:59 AM
There is at least one fella here who advocates doing it old school and using a 20 inch diameter grinding wheel,and low speed. If you can get one of those and lug it into your shop you will be set for life

ian maybury
06-19-2015, 8:08 AM
The basic difficulty is always the need to remove quite a lot of metal, but at the same time to avoid overheating the steel. Especially if grinding close to a sharp edge. There's a variety of methods that have been discussed here at differing times. The problem that tends to arise is that their relative rates of metal removal and heating tendencies don't get discussed in detail - there's a very big difference between cutting a whole new bevel, and just re-cutting an old one. Few i guess have tried all of the common methods:


Disc sanders with 80 grit or coarser aluminium oxide will do the job, but entail living very dangerously because they cause lots of heating. (the need to work only in very short bursts makes it relatively slower)

Belt sanders on a coarse belt get the job done, and while seemingly better than a disc still need a lot of care to avoid overheating.

Bench grinders with a very coarse and friable wheel and lots of care work well if a hollow grind is OK and you don't mind the dust. (the choice of many)

CBN wheels up the ante in terms of cost, and need right handling and set up - but shift metal really fast for minimal heat input. (they don't work on mild/soft steels or non ferrous metals)

Long lengths of coarse aluminium oxide paper stuck down on a long flat surface used with a means of holding and applying downward pressure on the iron seem to get the the job done, but to need care to avoid dubbing.

A WorkSharp (off the accessory top surface) or Veritas equivalent handles light grinding with great control (but isn't fast enough to recut a whole new bevel on a thick iron) with minimal heating. (especially with a diamond lapidary disc)

Warren Mickley
06-19-2015, 8:19 AM
This reminds me of the escaped prisoners. They "had to have had power tools" because the experts could not imagine that anyone could operate a hacksaw for more than three minutes without giving up. One contractor admitted that the cut was neater than his best man could accomplish with a power tool, but still insisted it was done with power.

It sounds to me like you solved your problem in less time than it would take to buy and install a grinder. And since the iron will work fine when it is somewhat out of square, you may have done more than necessary. If you are going to rehabilitate a plane every week, buy a grinder. Otherwise problems like you had just don't come up very often.

george wilson
06-19-2015, 8:27 AM
We had those old large sandstone wheels in the museum shops. I tried grinding a plane blade on one for 3 hours one time,getting boys in the audience to crank the handle. Never did get it beveled that way. The wheels the museum could get were just too fine grained. I have an unused old Civil War period sandstone wheel that is much coarser. Discovered in the basement of an old warehouse in Norfolk that burned down. This guy was selling them for $5.00 each,to people who were putting them at the end of their driveway.(WHY do they DO that?) I got 5 and kept one.

If you don't know how to use a bench grinder,you need to learn how,seriously. You can take a small C clamp and clamp a piece of wood across the plane blade. Pull out the tool rest,and slide the piece of wood across the outside edge of the tool rest.

That way,all you now have to worry about is burning the edge. Grind for 2 seconds and quickly dip in water. Use a coarse white wheel. Sharpen the wheel by dragging a diamond across it.

David Ragan
06-19-2015, 8:35 AM
I read something interesting about this.

When grinding blades, take some hot glue, and put a piece of sponge across the edge, and then keep saturated with water, so the blade remains cool:rolleyes:....

What a nifty idea! Has anyone ever tried this?

ian maybury
06-19-2015, 9:00 AM
Hi Warren. I guess to be fair the big issue in grinding irons is the little matter of whether or not the task is to re-work an existing bevel (e.g. to take a nick out, or get back to a fresh bevel), or to cut one from scratch/re-angle a thick iron. We rarely distinguish between these extremes when we discuss grinding.

Guys like yourself at it for yonks using tools that have long since been set up may also tend to lose sight that the latter possibility can arise - but some of us have been known for example to order irons with the wrong bevel angle - and get into re-angling them before fully realising this distinction.

No matter how it's done 90 minutes would sound fast for a job requiring heavy metal removal - :o i've spent a whole day re-angling an iron….

Derek Cohen
06-19-2015, 9:00 AM
I am wondering what's the best way to do the rough work on a bevel that's at an angle. The bench grinder seems to bite the snot out of it every time I touch it.

1. Mark a line square to the side of the blade as close to the back of the bevel as you can.

2. Grind back to this squared line without a bevel (squared edge)

3. Now grind the new bevel (I use an 8" dry grinder).

Regards from Perth

Derek

Archie England
06-19-2015, 9:41 AM
Tormek does this type of correction exceptionally well. Time from start to finish: less than 30". However, it's a costly investment.

Andrew Pitonyak
06-19-2015, 10:33 AM
I own a Tormek. If I need to do serious work, however, it is just too slow. So, when I had a bunch of chisels that were really messed up, I purchased a piece of junk slow grinder on sale at Woodcraft. Wish I had spent more on something marginally nicer, but, it gets the job done.


I've lurked within (and enjoyed) this forum long enough that I figure I should eventually make a first post...

Lots of content for a first post!



Forget the fancy (and expensive) wheels out there. Go for as coarse a wheel as possible 36 grit is excellent but no higher that 60 for carbon steel. Use the white wheels for HSS or softer materials. Use a dressing tool (diamond, silicone carbide, etc - don't be afraid to use this tool often, just apply a very light touch and it should last you many dressings) to create a 'crown' on your wheel so that only the very center of the stone can remove any material.

I was completely not aware of this.... Obviously I have much to learn. I guess I need to figure out what dressing tool to purchase.



Lets address the tool rest, most are horrendous and should be outright replaced but oftentimes a small piece of hardboard attached to the stock rest polymorphs a meh device to something quite usable.


I should look into this. The tool rest on mine is total garbage. I mean, for my purposes it does the job, but poorly. Of course, I only use it for very rough shaping before I take it to the Tormek for the final rough shaping.


I hope this was useful to you and best of luck.

Yes, indeed it was.

Andrew Pitonyak
06-19-2015, 10:46 AM
I created new bevel using a belt grinder and stones, and now it's fine, but it took approximately a century. Okay; 90 minutes. I am wondering what's the best way to do the rough work on a bevel that's at an angle. The bench grinder seems to bite the snot out of it every time I touch it. The belt grinder is a lot better, but still has the potential to create problems pretty quickly.

Should I just go out and get a big carborundum whetstone? Maybe a coarser DMT diamond stone is the answer.

I don't remember who said it, but Diamond stones are generally not course enough to do significant work fast enough when you have a lot to do. So, he recommended sandpaper. Off hand, I think it was Derek Cohen, and I think that it was related to "what is the best way to flatten the back of a plane blade", but, I am inclined to agree with that statement in general. I know that you can get diamond wheels, but I have no experience with those (but I do remember them being discussed here at one point).

In an effort to spend less money, I would recommend that you first try to see if you can do the very rough work on the grinder that you have (using some tips provided by others), and then use some other method to finish out the bevel (which I would do on the Tormek very quickly and safely).

For me, the time consuming part is flattening the back. I had trouble doing this on the Worksharp 3000 (so I gave it to a friend who LOVES it), many claim success so it was probably my own problem. I saw one guy flatten a back on a Tormek stone, I failed on that too and won't do it. Derek Cohen seems to have the best method down with long sandpaper and a large magnet (no idea where he got that). Sadly, I was not able to find the post.

Brian Holcombe
06-19-2015, 10:53 AM
I change the bevel angles on most japanese chisels that I have, I think that they're setup for softwoods and since I use them in hardwoods I prefer a steeper bevel (30~ for bench chisels). I have been doing this on granite with sandpaper for the last round of chisels and it takes about a 1/2 hour to get the bevel. Not terrible, but can get old when doing a full set of chisels.

I've considered a tormek, but once I get the angle established my routine evolves to a maintenance which is much simpler.

A2 plane blades on the other hand....would not mind a grinder for those.

Steve H Graham
06-19-2015, 11:02 AM
This is all interesting stuff; especially the post about the 20" wheel. I think a wheel with a big diameter would be a big blessing, because it would be much flatter than a small wheel at its outer edge.

It's too bad no one makes an expanding wheel for sanding belts, the way they make expanding drums. That would be neat. Now that I think about it, I kind of wonder if my oscillating spindle sander might be good for this. It's really easy to do precise work on it. It's nearly useless for most metal work, so I never really though about using it to sharpen things, but for this purpose, it might be fantastic. Maybe I'll dig up a scrap blade somewhere and fool with it.

Again, I guess I was stupid to get rid of my 1800 RPM grinder, but I was doing machining, and for that purpose it was totally, 100% useless. On HSS lathe tools, my fast bench grinder is a joy.

Based on my success with the diamond stones, I think the easiest solution is a DMT coarse stone. I really tortured myself with the fine stone.

If I can get a grip on using my little Rockwell 1x42 grinder, maybe I can avoid getting a second bench grinder and increasing clutter.

Brian Holcombe
06-19-2015, 12:20 PM
You can get a 14" contact wheel for a beltsander.

There used to be a major manufacturer of very high quality knifemaking beltsanders, but the name escapes me at the moment. I used some of their parts on the one I made for myself that is currently in use at my fathers shop. I built it when I was a kid and used a flat platen because I preferred to flat grind my knives. I have contemplated converting the sander to a contact wheel and going for a rather large one, or just buying a professionally made machine (I built mine when I was 14, so it has it's plusses and minuses).

Here is a current manufacturer;
http://www.beaumontmetalworks.com/shop/item.aspx?itemid=64

I used a variable speed motor on mine, and the purpose of doing so was that I used it to rough out the finish on hardened blades. One would normally work the finish to a certain level prior to finishing with some expectation that they will be working the finish again after heat treating and the initial stages of doing so were much faster on a belt sander than by hand.

Steve H Graham
06-19-2015, 12:45 PM
I would love to have one of those. I am hoping to make one eventually. The little 1 x 42 I have is really useful. I put a treadmill motor on it, and I can run it at all sorts of speeds.

I found a site called Supergrit.com. They have the correct grease stick for the belts, not to mention a huge selection of obscure abrasives.

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Steve Voigt
06-19-2015, 1:07 PM
If you walk into almost any professional shop, what you will find is a dry grinder, most likely with inexpensive grey wheels. That's because it's both cost effective and time-efficient. You can splurge and spend a hundy on a new one from a big box store, or you can find find one on Craigslist for as little as $20.

Lots of people are either unable or unwilling to learn how to use a dry grinder without burning the tool, so they will steer you toward things like Tormeks and whatever. You can go that route if you want to waste time and money, but I would listen to what George Wilson said earlier in this thread.

If you prefer to go a non-powered route, you might consider a Crystolon stone--much cheaper than diamond, and very fast.

Also, just a general comment. A lot of the questions you are asking--how to sharpen, how to joint an edge, etc.--are very fundamental questions, and it would probably help you a lot to consult some basic hand-tool woodworking texts. There are tons of books on the subject, and your local library probably has a bunch of them.

Don't get me wrong, I'm not trying in any way to discourage you from posting these questions. Just be aware though, that on a forum you will get a zillion different answers to every question, and not all of them will be good answers. For example, in the other thread, a bunch of people suggested various crutches like match planing or using a fence. If you read most reputable texts though, they will just tell you to joint the edges one at a time (unless you're dealing with thin pieces like drawer sides). The other methods simply aren't necessary.

My point is, for almost any basic task, there is a standard accepted way it's done. Books can be more helpful than forums for figuring that out, because forums have no filter.

Andrew Pitonyak
06-19-2015, 1:10 PM
This is all interesting stuff; especially the post about the 20" wheel. I think a wheel with a big diameter would be a big blessing, because it would be much flatter than a small wheel at its outer edge.

I like the hollow grind so that I can more easily free end during the maintenance stage. I rarely use my Tormek since after I have the hollow grind it is trivial for me to keep things sharp freehand on my water stones. I have some crappy cheap chisels that I sometimes use, have not thrown them on the Tormek in a very long time. Think I need to follow Mr. Holcombe's lead and sharpen that one at 30 degrees. Of course, I have been doing the free hand so long with this one that I think that I need to re-establish the bevel. I can hardly use it without the edge folding over, was not the case previously (even if it is cheap and prone to folding over). Well, either that or delegate it to simple paring since it is wicked sharp with the narrow fragile tip.

Steve H Graham
06-19-2015, 2:18 PM
Also, just a general comment. A lot of the questions you are asking--how to sharpen, how to joint an edge, etc.--are very fundamental questions, and it would probably help you a lot to consult some basic hand-tool woodworking texts. There are tons of books on the subject, and your local library probably has a bunch of them.

I appreciate the suggestion. I do like hearing about different ways of doing things, though.

Jim Matthews
06-19-2015, 3:20 PM
Check to see if your files are harder than the steel that needs grinding.

A good bodyshop file makes quick work of most of my grinding jobs.
I doubt it would work on modern powdered steels which are amazingly hard.

I've got a knife maker's belt with 80 grit for the stuff my files won't cut.

Mark, grind to the line and dip it in a coffee can full of rusty water and tailings.

Steve H Graham
06-19-2015, 4:12 PM
It never occurred to me to use a file. I had just assumed the steel was too hard. I'll try that.