Throw it Away???

[Teresa Jones]

Regarding my earlier hand plane question:

I tossed the MDF and substituted Marble. I went back to 50 grit and started the process over. I still cannot seem to get the sole reasonably flat.

Here is what does not make sense to me. I mark the sole with a black sharpie to monitor my progress. Invariably, the mark is removed first from the outside edges. Strange thing is, when I put my engineer's square across the width of the sole, it shows to be HIGH in the MIDDLE. I can see light at the edges but not in the center of the sole.

Is it possible I can be rocking the plane that much when moving it across the sandpaper?

Thanks again,

TJ

[Glenn Clabo]

Is it possible I can be rocking the plane that much when moving it across the sandpaper?

TJ

TJ,
It sure sounds like that's what's happening. You are holding and pushing it heel to toe right? If you are sliding it side to side at all it will crown. It only takes a slight rocking.

Just something to try...if you haven't. Put the granite and paper below your waist not up on the bench. Keeping it below your waist, moving it only back and forth length wise (heel to toe), and using even pressure may help to keep it from rocking.

[Teresa Jones]

TJ,
It sure sounds like that's what's happening. You are holding and pushing it heel to toe right? If you are sliding it side to side at all it will crown. It only takes a slight rocking.

Just something to try...if you haven't. Put the granite and paper below your waist not up on the bench. Keeping it below your waist, moving it only back and forth length wise (heel to toe), and using even pressure may help to keep it from rocking.

Glenn,

Thank you for the suggestions. I am moving the plane heel to toe across the abrasives. I moved the plane as though I were using it to plane a piece of wood.

I will give your suggestion a try and let you know how it turns out.

Thanks again,

TJ

[Bruce Page]

Glenn,

I am moving the plane heel to toe across the abrasives. I moved the plane as though I were using it to plane a piece of wood.


TJ,
I was taught to use a figure "8" motion when sanding / lapping a flat surface. The figure 8 motion lends itself to a more even & consistent material removal. Lapping in a figure 8 motion takes a little practice to get used to, but it will yield better results.


The trouble with jogging is that, by the time you realize you’re not in shape for it, it’s too far to walk back. — Franklin P. Jones

[Glenn Clabo]

TJ,
I was taught to use a figure "8" motion when sanding / lapping a flat surface. The figure 8 motion lends itself to a more even & consistent material removal. Lapping in a figure 8 motion takes a little practice to get used to, but it will yield better results.

Bruce,
To explain....
Like many things in this world of tools and wood there are many ways and thoughts on how things are done right. I was taught (very old all around machinist who started out as a carpenter) that there are many ways to do things... but the one that works for you is the right one.

Here's what I think...fwiw...

Figure "8" is good for flat (not tall) material. It allows a flow and an even action. Most of all it wears the sharpening tool flat. But when you are working something with height it gives you more chance for rocking. The difference between a knife and a plane is the sharpening plane. In this case if you keep the possibility of rocking to a min you have better success. It's not real important to make sure that the sides are square to the bottom. That's why I suggested that she keep it below her waist and move it heel/toe. It reduces the possibility of rocking because you don't stretch your arms and you move your body less. You let the tool sharpen it's self. Once you get to that point you can "feel" what not rocking is like.

Again...this is just the way I think...not always right for everyone...just my suggestion.


p.s. My parents and sisters lived out there in Los Alamos for 15 years. Mom and Dad are now in TN.

[Bruce Page]

Glenn,
As another ex-machinist (30+years) but not as old, :D :D I agree that the figure 8 motion does not lend itself to taller pieces, but should work very well for a plane sole. One of the main benefits of the figure 8 is that it “balances” the natural body motion, e.g., one area or corner is not favored over another.
One of the exercises during my apprenticeship was to fabricate two sets of 1-2-3 blocks out of 4130, heat treated to Rc60. They had to be flat & parallel, and square to within +/-.0002 or better. We were allowed to grind them down to +.003 but had to hand lap them from there. I spent days working those stupid blocks but passed the test.

I agree that there’s more than one way to skin a cat, but the 8 motion would be my approach in this case.

I Love Los Alamos! They moved me out of Los Angeles!!! I spent 8 years at LANL before moving down to the “big city” and working for Sandia Labs.

Here’s a pic of those infamous blocks – I still use them!

[Glenn Clabo]

He's the oldest of the old machinists....And he is chock full of opinions.:D

[Bruce Page]

He's the oldest of the old machinists....And he is chock full of opinions.:D


Glenn, I think you’re right – I’ve never known two machinists to agree on anything! ;)

[David Rose]

I didn't see length mentioned on this plane. Now, Knuckle Draggers, don't throw me out of here. :D

What I've done on some of my shorter salvaged planes was to use a stationary belt sander as a start. The one I use has a platten (metal plate behind the belt about 14" long. I attached a piece of glass to it with carpet tape so it is trapped between the platten and belt. The glass was a little longer than the plane soles I was doing. The grit markings have worn off the belt, but I'd say it's about 180. It is still fairly slow cutting but with two handed uniform pressure it will cut fairly evenly. Then go to paper on glass or solid surface.

For going by hand, I would not hold the plane by the handles if going in a figure 8. If you grab the top edges of the sole I think you can keep it flatter. I'm not an experienced machinist, but have 35 years of gunsmithing. This might equate to a few years of experience in machining. At least I've been "there" long enough to develop contrary opinions. :D Or at least to get contrary...

As was said earlier, and the reason people have different opinions, is that we all have different body builds. Some guys can file a nice flat. Others with lots of experience still struggle with it. Part is developing what works you the user and part is practice practice practice.

David

[Ben Knebel]

Hi TJ;

Convexity in the centre of the sole is the hardest thing to get rid of as it tends to induce a rocking side to side to side without you noticing you are doing it---it can actually get worse the more you lap. As you press down you compress the centre of the paper more than the edges because of the high in the centre which reinforces the convexity.

I would suggest the following:
Turn the plane upside down in a vice and file the sole flat before moving to papers on stone or glass.
The best way to do this is to draw file the sole. When you draw file you hold the file as you would the handle of a lawnmower and draw it across the metal towards you. Imagine the high spot in the centre and concentrate on taking it down. Use your sharpie to mark the sole and then draw the file across the sole so that you are removing metal from the centre only---you'll be surprised how easy this is to do. After that just lap as before but let the weight of the plane do most of the work using your hands for a little downward weight but concentrating on pushing and pulling the plane across the lapping surface.

Alternatively you can scrape the high spot out--if you have a hand scraper you can use it about the same way you would on wood. I have a couple of old machinists rules that work surprisingly well as scrapers.

In any case the above process works for me--it might for you as well.

Regards
Ben
www.shepherdtool.com

[Glenn Clabo]

Ben,
What can I say but ... I am not worthy. :D You make too much sense.

[Ben Knebel]

Hi Glenn;
The secret is to be lazy and I'm lazy as they come when it comes to avoiding unneccessary labor. ;). After lapping the soles on a lapping plate for countless hours on the first dozen or so planes I built I said enough of this nonsense and moved to something faster.
I too will start on a belt sander---a fresh belt works surprisingly well to flatten the sole and then move to papers on a hunk of steel plate I had machined flat.
In most cases this saved me about 4-6 hours per plane fron the getgo--but every once in awhile I'd have TJ's problem---so I tried drawfiling and found that what I had just spent 4 hours trying to eliminate dissappeared in about 20 minutes of drawfiling. I then tried scraping and that worked nicely as well except if you end up with a nick in the scraper you can score the sole and give yourself more work than you intended.

I'd also advise TJ not to have coniptions if she see's light under the straightedge --the human eye can distinguish light from dark given a space much less than 1 ten thousandth of an inch and if that's all that TJ is looking to elimate I'd say stop--you're more than close enough.

On almost all planes any variance in the soles flatness up to a few thou (1-4) makes no nevermind. Only planes that are used for final smoothing need to have as flat a sole as possible.

Kind regards
Ben

[Teresa Jones]

OK guys, many, many thanks for all the helpful suggestions.

Try, try again did not get me very far, so I came back and reread all of your post. What I read between the lines - I NEED A MACHINIST!

So, I dropped off the plane on Friday at a machine shop.

Will let you know how it turns out. He quoted about $10, much less than what I've already spent on sandpaper, not to mention time.

Not having any trouble sharpening chisels and blades.

Thanks again - SMC rules!!

TJ

[Michael Stadulis]

Hi Theresa,

A suggestion for you before you throw your tool away. I think that your problem may be that lapping makes a nice bed of dust, and you'll note that it builds up the thickest in the middle of your paper. Try vacuuming constantly, so there is no dust pile on which the plane will rock. It always seemed to do the trick for me. I know this stuff is messy and you naturally want to keep working but your problem may just be the thick dust that raises the center of the plan and causes the ends to be abraded more. Make sense?

Michael Stadulis
Gloucester County, NJ

[Teresa Jones]

Picked up the planes from the machine shop at lunch today.

The guy said one of them was out by '12' and the other by '8' if anyone wants to educate me on exactly what that means!!

Anyway, the soles look good with only minor low spots at the back edges. It will be interesting to put my straight edge to it and see what it says now!!

Again, my sincerest thanks for all your input. I'm not giving up on learning to do this correctly myself. I have a few more planes to tune, but at least now I have a couple to work with on my projects.

Michael, I will try the vacuum approach. I was occassionally brushing the sandpaper free of the dust and there was a lot of it so you may be on to something.

Thanks again everyone!!

[Bruce Page]

Teresa, he was talking in thousandths as in .012 & .008 Both numbers seem high to me considering how much time you spent sanding them.
I’m assuming that he ground them?

[Teresa Jones]

Teresa, he was talking in thousandths as in .012 & .008 Both numbers seem high to me considering how much time you spent sanding them.
I’m assuming that he ground them?

Bruce,

Yes, he used a surface grinder to remove the metal. So I guess that means he had to remove that much metal?

I thought that is what he was saying. I'm an accountant, so numbers that small do not usually mean anything to me!!

I put them to the test with my straight edge. NO light. I now know what flat looks like!!

TJ

[Bruce Page]

Bruce,

Yes, he used a surface grinder to remove the metal. So I guess that means he had to remove that much metal?
TJ

Yes, on a surface grinder you usually start from the highest point and go from there. You mentioned that he quoted about $10 – that is a hell of a good deal. Around here they won’t even talk to you for less than $50!