Hand plane sole flatness?

[Sawdust=manglitter]

Thanks Custard, that's why I use drugs that piece of spalted English walnut to test the plane on.

Thanks Andy, I'll have a loook for those posts. Sure I've seen GT85 being mentioned somewhere too

 

[rafezetter]

Pound store window cleaner here, can be as liberal as you like for nowt. Prefer it to water, especially for lapping as there's less chance of rusting occuring if it's not thoroughly dried. Some people prefer gt85 / wd40 but I've always been wary of residue transfer to the wood.

 

[Phil Pascoe]

I use isopropyl alcohol on my stones and diamonds, it just wipes off perfectly cleanly.

 

[ED65]

That looks ace, well done.

Now with respect to everyone else I think they missed an important point here yesterday in that you could probably have stopped at the stage shown in the first photo! To me that looked more than flat enough to work well. Flat (co-planar) in front of the mouth is important, at the rear edge of the mouth, not so much. As long as there are shoulders to both sides to provide the necessary support, which you already had. That hollow behind isn't just okay to leave, it may actually be preferable.

Also, since you say it can take some nice shavings now, out of curiosity did you check it before starting work and it didn't? I only mention it because it's so common these days for people to go ahead and lap regardless, when there's a decent chance a plane without a lot of wear will already do what you need it to do. One should always check first before going ahead with flattening, whether by scraper or by lapping.

 

[ED65]

60 grit is now my preferred choice, once it looses it's bite I move to a fresh piece.

I would use 60 too if I could get it easily. Once the need for flattening has been established then I immediately reach for 80, and fresh 80 if I have it. I might do a quick few passes with 150 to just give a quick read on flatness before starting but I'd only stick to that if the sole were already very flat and I was just tarting it up a bit.

If there is any decent amount of metal to remove I would never begin with anything finer than 80, even for something as small as a block plane. Now that I have been lucky enough to acquire a proper scraper though it's time to try scraping instead of lapping \/

 

[xy mosian]

60 grit is now my preferred choice, once it looses it's bite I move to a fresh piece.

I would use 60 too if I could get it easily. Once the need for flattening has been established then I immediately reach for 80, and fresh 80 if I have it. I might do a quick few passes with 150 to just give a quick read on flatness before starting but I'd only stick to that if the sole were already very flat and I was just tarting it up a bit.

If there is any decent amount of metal to remove I would never begin with anything finer than 80, even for something as small as a block plane. Now that I have been lucky enough to acquire a proper scraper though it's time to try scraping instead of lapping \/

Belts for belt sanders are available in coarse grits. I certainly have 60. They are also a convenient shape, when cut, for plane flattening.
HTH, xy

 

[D_W]

That looks ace, well done.

Now with respect to everyone else I think they missed an important point here yesterday in that you could probably have stopped at the stage shown in the first photo! To me that looked more than flat enough to work well. Flat (co-planar) in front of the mouth is important, at the rear edge of the mouth, not so much. As long as there are shoulders to both sides to provide the necessary support, which you already had. That hollow behind isn't just okay to leave, it may actually be preferable.

Hollows behind the mouth like that of any considerable distance can cause trouble on the edges of boards or if you're smoothing any piece that's not wider than the hollow (thus the question that I had about just jacking, or smoothing and jointing. Even if you're using a smoother, eventually you will joint something with it).

It's best for a plane to have that stuff removed even though it's not vital. A plane biased in favor of the user will generally have the toe and heel a couple of thousandths proud (but not much more than that if you can help it).

I have a method to flatten planes within the thinnest feeler you can find, but it requires a little more than just lapping (the extra cost is only a good file, though, maybe 10 quid - but it has to be a file that has just enough spring and with the teeth nearly all the way to the end so that you can cut [ file or draw file] the center of a plane without cutting the sides).

The next time I flatten a plane, I will show it. It's something that will allow a user to square a plane by hand, too, which is otherwise fairly hard to do. Not something you'd do all the time, but I never heard anyone give me a good explanation of how to do it other than to scrape with a biax (which can do damage in inexperienced hands, and is also *extremely* expensive).

 

[custard]

The next time I flatten a plane, I will show it. It's something that will allow a user to square a plane by hand, too, which is otherwise fairly hard to do. Not something you'd do all the time, but I never heard anyone give me a good explanation of how to do it other than to scrape with a biax (which can do damage in inexperienced hands, and is also *extremely* expensive).

I've never squared a bench plane, but shoulder planes are a different matter...not that I've ever been that successful! So I'll look out for your post with interest.

One more thing, what's a "biax"?

 

[iNewbie]

http://www.biax-germany.com/en/produkte ... ry=schaber

 

[custard]

Mmmm!

Likey, likey.

 

[D_W]

Mmmm!

Likey, likey.

Can't even find them cheap used. Somewhere in the range of $1,500 used for one that works. Double that new.

Simonds maxi cut file works with my method and costs $8 delivered here (probably removes metal a lot faster than a biax, but folks good with scraping can, I'm sure, get to tolerances that are in the ten thousandths of an inch. I don't want to scrape, though. It's difficult work and slow.

I don't have any out of flat planes, so it could be a while (like until I get the next infill built), but I am going to make a video of it because people should be able to make their planes really flat if they'd like to - all you have to have is a good quality straight edge, a lapping surface and a file with the same characteristics as the simonds maxi cut files.

 

[Sawdust=manglitter]

I'll also be keeping an eye out for your plane flattening post/video with interest

 

[bugbear]

is any decent amount of metal to remove I would never begin with anything finer than 80, even for something as small as a block plane. Now that I have been lucky enough to acquire a proper scraper though it's time to try scraping instead of lapping \/

Speaking as someone who has used scraping on a plane, I recommend against it.

Mind you, I also recommend against lapping.

I like flat planes though.

BugBear

 

[Cheshirechappie]

Modern engineering practice is to machine the surface flat - or where real precision is needed, machine off the bulk with a milling machine or similar, then refine the accuracy and surface finish by grinding in a big, rigid machine. (Obviously, a non-starter for the average woodworker.)

Older engineering practice was to machine to almost finished, then achieve accuracy and finish needed by hand scraping. (Still a non-starter for most woodworkers - milling machines are not stardard woody kit!)

Even older engineering practice (probably defunct almost everywhere except in emergencies by about WW1) was to chip the bulk off the casting with crosscut and flat chisels, then file almost to a finish, then scrape.

In each of the latter cases, the scraping removes only the last thou or two, any more than that takes ages! Filing, on the other hand, can remove cast iron quite quickly (no need to chip an existing machined plane casting with chisels even if it's warped quite badly), and with the right files and reference surface to work to, and a methodical approach, is surprisingly quick - certainly quicker than lapping on abrasive sheets. It can also leave a surface accurate enough for a woodworking plane without resorting to scraping, though working through the grits of abrasive sheets to the finish you desire can improve polish once you've established the accuracy.

The one downside of this method is that you do need an accurate reference surface to work to (engineer's surface plate, for preference), and some non-woodworking tools like marking blue and a suitable selection of files; thus, it's a great method if you happen to have those to hand, or access to them, but something of a non-starter on cost grounds if you haven't.

That realistically leaves the average woodworker with a sheet of float glass and some abrasive papers of various grades as the most cost-effective, though not the fastest, method.

 

[D_W]

If you're going to do what I'll show, you only need one file, but you do need abrasive paper and float glass. I don't know how perfect the flat surface has to be. Mine is very close to it (perhaps not able to slip a .0015" feeler between an undamaged starrett 24" straight edge and any point on the surface, and the support for me is 4 1/8" of ash and I work over a leg, so it may stay relatively close to that. I'm sure that level of flatness isn't required, though). I also have two granite reference surfaces, but I never need them.

I do have marking fluid, but someone could use a magic marker or something easy. If one already has the straight edge and the lapping surface, all you really need is a file that looks like the one I attached here (this is a simonds black maxi.), and a file card.

https://s2.postimg.org/3l34v9wcp/s-l1600.jpg

The challenge with lapping only is that you will have a very hard time doing much metal removal and still be within a thousandth or two. You can certainly make a functional plane, though. The challenge is several multiples greater when you move to infills and start trying to lap mild steel instead of cast. It laps so slow that it's untenable, and draw filing (or filing in general, maybe not specifically draw filing) becomes the only reasonable hand method if there is more than a little to remove. Plus, you may pein everything together and find the sole proud a hundredth in the middle, which is a horrible situation for hand lapping, as you have to remove that hump and you may still have some cosmetic stuff on the ends to get through. I have no idea how long it would take, but that was the situation on my last infill and I wasn't willing to find out after I blew out one application of 80 grit PSA roll in about 5 minutes and didn't get very far. I would've also ended with a plane that had proud ends, and I didn't want to do that.

Here are the steps to what I do:
* examine the sole of the plane with a straight edge (a really good one that is known to be super straight). If you have a good lap, you can start by running the plane down the lap a few times with coarse paper, it will mark the high spots.
* If the plane is high on the ends (ends touch a flat surface, but not the mouth) and made of cast iron, you can continue to lap if you'd like. You'll end up with a very flat plane if you stop at the right point, as long as the plane isn't coffin shape (coffin shape metal planes tend to end up with the sides relieved as well as the ends because there isn't enough forward and rearward metal, I guess, to keep you from accidentally dubbing the sides). If you overshoot, then you can go to filing below.
* file the high spots with said file above by applying the file diagonally on the surface of the plane where the high spots are, but not overlapping the edge and with gentle care if crossing the mouth - no crossing the mouth if the file is pinned, and no harsh work at the mouth even if it isn't. The way to do this is to put fingers on top of the end of the file with the non-dominant hand and pull up on the handle with the non-dominant hand a little bit and push in short strokes. In doing this, you are flexing the file a bit and quasi draw filing with the first inch or two of the file only, never filing on the outside perimeter of the sole, but staying within it. As an amount of swarf builds up on the plane, stop and brush it off, and check the file for pinning. The files I showed above will flex slightly and you can quickly file material without filing sides or edges of the plane sole, and the file has teeth all the way to the end (or close to it), so it's not just rubbing the surface. They come with a handle here for 8 bucks and I haven't worn one out yet. They are also great for draw filing elsewhere because the broken tooth pattern is fast for rough work, but will still draw file.
* stop from time to time and lap the plane again. Lap until the filed area disappears. The high spots should be less high, but still should be discernible from spots that are either not yet lapped or that have been filed and are not being contacted by the lap.
* continue the filing process, filing in the center (inside the perimeter of the plane on the high spots if they are somewhere other than the center) and lapping to bring down the edges to the place where you filed being careful not to over file the center. As you get close to flat, the filing done each iteration should be less and less so that you don't run the risk of leaving a large amount to lap out. that is, if you think you're taking a thousandth off with the file or two thousandths, as you get to the end of the process, you should only remove a fraction of that and then lap the work out, remove a fraction, then lap the work out, etc. As you approach getting a lap that covers the whole bottom, the entire plane should be flat. If it is not, continue iterations until it is.

There are two points of care that have to be taken:
* If the file pins, you have to stop right away and card it (for the newbies - that means if it clogs, you have to use a special stiff wire brush, a "card", and get the pinning out) . Pinning will leave a deep scratch that you have to work out. If you are only working on a high spot, it's not a huge deal but:
* care must also be taken to make sure that you don't run a pinned file over the mouth of a plane. The pinning that is deep in an expanse of metal will be large dents at the edges going over the side of the mouth at the back and into the wear at the front. They'll never come out unless you still have some mouth that you need to file away (if making an infill, this should be done before the mouth is filed to finished size). Even then, the damage may be deep enough at the drop offs that you don't get it all out.
* I guess there is a third. The file should work inside the perimeter of the plane only and the lap finish the work to consolidate it all. If the file is allowed to overrun the ends, a low spot will almost certainly be created somewhere.

I don't know if that's clear or not. The file and the back and forth are the nuance. I am sure that the average person can do better than 1 1/2 thousandths with this, because I can. It's also something that on a pretty horrible smoother sole made of mild steel, you can do all of the work in about an hour. A machinist won't approve, but machinists can take a flying leap through a rolling donut if they think they are experts about what makes a good woodworking tool.

I never lap with anything higher in grit than 80 grit. It's a waste of time. I intentionally finish the process with worn paper that is cutting slightly slow, and if it's not cutting slow enough, I find another plane and lap it for a little bit to take the initial snot out of the aggressive paper. The file is doing the work, and the lap is only doing a little. If I think I need a better surface finish than worn 80 grit paper, then I lay a piece of 220 wet and dry on top of my 80 grit lap and use it only enough to make the surface a little more refined, and then after that, a wisp of scotch brite and a careful cleaning of the metal with vigorous brushing.

Include a file card in the cost of this if it's not had. I don't do this for all cast iron planes because they lap quickly and you can get very good functional flatness, unless they are already a banana to start. I may start doing this on long planes if I buy any in the future, because they are hard to lap unless they start with their ends low (mouth proud of the surface).

Nobody needs the feelers, I was just curious about what I was attaining. I wouldn't use cheap feelers, either. They're not reliable, and good ones are not expensive. I also wouldn't use a cheap straight edge if you are talking about a couple of thousandths - starrett is it, and they're not cheap, but a 24" starrett 380 won't be the most expensive thing in the shop, either.

This is actually a very easy process, the only thing that you end up doing is sweating a little bit. I'll still make a video of it. Other people should know how to do it, it's cheap, and knowledge is free.

The ability to square is pretty much the same thing, mark the high spots after the sole is flat and file them off until everything is close enough to finish (cosmetically) with a lap on the 80 grit. the work after that for cosmetics on the sides can be done carefully with a small block and sandpaper, being careful not to do more than just improve the cosmetics - no need to overdo it and sand a bunch of additional material off.

 

[D_W]

by the way, if someone tries my method above, I'd like to hear how you find the results. I take some of this a bit beyond what the average woodworker would, but for two reasons:
* lapping a mild steel infill will get you not very far and not very fast
* if you're making infills, they don't need to be flatter than lapping (that's a boutique tool and modern user want, but not a practical need). However, it just seems like a nice thing to do to make the thing dead flat if you spend 50+ (possibly three times that much if you make something really nice with a lot of hand work) hours making it.

Then there's also that bit about wanting to be able to make a plane square for a lot less than it costs (and in no more time than it takes to mail, arrange details and receive back) to have someone with a surface grinder do it.

I don't want to spend a lot of money, too much time, or have to buy a machine to do any of this, either.

Still going to make a video. I asked my good friend George what he did to make his "elephant plane" flat and square (picture below - the elephant is hidden in the cheek line), and he responded "flake and scrape" , or whatever machinists call that. George can do about anything. I can't (george also uses a biax and has experience reconditioning very high dollar high precision machines - I don't and wouldn't be able to on those two things). I couldn't make hand scraping work fast enough and you can still wreck edges and mouths very easily. The attached plane sold for about what Holtey would've charged for a similar sized plane - I'm lucky if I can get the cost of materials and tools back out of the planes that I sell, but I'm OK with all of that if I can make something work within reasonable constraints and time.

https://s2.postimg.org/6ct2knvcp/PICT0011_copy_1.jpg

I think the fact that I'm working with low skill means that anything that I can work out will be something that will be easy for other people to do, and it will generally be cheap, too.

 

[ED65]

Hollows behind the mouth like that of any considerable distance can cause trouble on the edges of boards or if you're smoothing any piece that's not wider than the hollow (thus the question that I had about just jacking, or smoothing and jointing. Even if you're using a smoother, eventually you will joint something with it).

It's best for a plane to have that stuff removed even though it's not vital.

I realise you didn't over-sell the problem here but I think it's worth saying anyway that those are at least as much theoretical disadvantages as practical issues.

Japanese planes argue strongly that our Western notions of flat soles being as important as we tend to think are a little, ah, two dimensional

 

[ED65]

Speaking as someone who has used scraping on a plane, I recommend against it.

I am surprised to hear you say that!

Mind you, I also recommend against lapping.

:mrgreen:

 

[D_W]

Hollows behind the mouth like that of any considerable distance can cause trouble on the edges of boards or if you're smoothing any piece that's not wider than the hollow (thus the question that I had about just jacking, or smoothing and jointing. Even if you're using a smoother, eventually you will joint something with it).

It's best for a plane to have that stuff removed even though it's not vital.

I realise you didn't over-sell the problem here but I think it's worth saying anyway that those are at least as much theoretical disadvantages as practical issues.

Japanese planes argue strongly that our Western notions of flat soles being as important as we tend to think are a little, ah, two dimensional

if you use a japanese plane on a surface for a while, you'll generally end up with out of flat characteristics. At the american kzerou-kai, the attendees can request to have the subject piece of yellow cedar run over by a western jointer to make sure it's true.

(I used japanese planes for a while, and still have a few. The hollow is created on the plane instead of just using it flat because it's a bias in favor of the user, and from a time when someone would've been on site and unable to find a perfectly flat surface. They work exceptionally well if you have one of those chinese reference granite plates and lap a sole entirely flat - at least as well as they work with the traditional setup).

In general, though I don't lap all of the planes that I have, despite the ability to do them all one way or another, I recognize that there are some minor nits that occur when I try to use the planes that I didn't work. Not deal breakers, but no reason to put up with them in the days when a $15 roll of PSA paper and a $20 piece of glass will take care of the problem for a dozen planes.

There is a user on SMC who is fanatical about japanese tools (Stan Covington) and if you get into a discussion with him (I consider him a friend, and don't mind discussions that are disagreements), he will tell you ten ways til sunday why japanese planes are better than western and why most of our irons are barely fit to make a burn barrel, but he uses a metal jointer because the typical japanese plane setup is really intended for someone who is using the plane every single day and who is willing to tune the plane daily if needed.

 

[Jacob]

Yep 80 grit wet n dry. Flooded wet with white spirit. Cheapest paper backed wet n dry will lie very flat in a pool of white spirit (or water) on a suitable base (I use my planer bed) and not need sticking down or anything.
When you have nearly finished do it to and fro against a bit of a fence (lath clamped on ) so you get straight lines parallel to sides
No need for feeler gauges etc you can see where you've been very easily.
No need to go further (it'll polish up quickly with use) but if you want you can move to a finer grit for a quick 10 seconds few passes (round and round any direction), which is all you need as this will take off the sharpness of the ridges and reduce friction. No need to remove the ridges, or polish, it won't make any difference once they've been topped off.
Then candle wax - quick scribble.

Not sure what 'lapping' is exactly but I guess it's an engineer's thing and will take a long time. Don't do it! Don't scrape, don't file!
Don't use Honerite (most single malt whisky is a lot cheaper and would work just as well) or any other proprietary product -
they are all a rip off, especially Honerite - one of the most expensive liquids you can buy (not counting Chanel No5 etc). Just white spirit or water.

NB I only use my planes for woodwork. :lol: