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Joel Goodman
09-16-2008, 12:11 PM
I would like to flatten the sole of a #7. A local company has a surface grinder and will take off the minimum amount of metal. My question is this -- I know I should have it ground with the frog in -- should the iron and chipbreaker be in too? I am trying to understand how they can effect the sole as the only put pressure on the frog. Or is it safer to have it all together? I assume I should snug down the screw that holds the blade assembly in a little extra so it doesn't loosen during grinding -- or should I? Is locktite a good idea? I don't really know how the surface grinding operation works.

I know this is wimpy and I should flatten it myself but I can't face it! I also know there are those who think all this flattening in a waste of time!

Thanks.

Pedro Reyes
09-16-2008, 1:52 PM
Joel,

Have you tried to at least pass it a few times over a flat surface with sandpaper? It may be that it is terribly out of flat, or it may be that you do half the work just trying to figure out how flat it is.

In any case, I would assemble it as it would be used (all in, blade retracted of course) before flattening, locktite hopefully won't be needed. I, however, would never take one of my planes to grind, too scared. What kind of finish are you getting? Wouldn't you need to sand that afterwards anyway?

just my $0.02

/p

mike holden
09-16-2008, 3:54 PM
Pedro,
The finish off a surface grinder can look like a mirror if a fine grit wheel is used.

Joel,
How are they going to set up the plane for grinding? If they are going to "come off" the side of the plane, are the sides parallel? If not, and you are right-handed, then tell them to use the right side of the plane to make the bottom square to. This will make the plane usable in a shooting board.
I would also advise you to take a couple passes over some sandpaper placed on a flat surface (your tablesaw would work). Scribble some magic marker over the bottom first so you can see what the bottom looks like.
But, the very first thing *I* would do, is sharpen the blade and use it. Flatten a board, check with a straight edge, if flat - you are good to go.
Dont get so hung up on perfection that you never make anything. Fine furniture was made with much less sophisticated tools than the worst tools offered today.

It's wood, it moves, if you want to work in microns, take up metalwork.
Dont sweat the small stuff.
Nobody looks at a nice piece of woodwork and says: "Wow! what a flat plane you had!"
Mike

Tom Henderson2
09-16-2008, 3:57 PM
Hi Joel-

I've often wondered about having the bottom ground.

One concern would be how they fixture it. If they have to clamp it laterally -- and I think they would -- it seems like you would have a lot of potential to distort the sole. Especially if the sides aren't perfectly perpendicular to the sole.

I know a very little bit about milling machine tooling, but absolutely nothing about fixturing for grinding. But it may be worth looking into.

Any idea what the cost will be?

-Tom H.

Clint Jones
09-16-2008, 4:05 PM
I know a guy who does this. He surface grinds the sole flat and the sides 90 degrees square with the sole. He has experience doing this to planes and several satisfied customers. If you would like I can refer you to him.

George Moore
09-16-2008, 6:24 PM
I have a couple of planes that have been ground by probably the same gentleman Clint is speaking of and he does a fantastic job.

He goes by TablesawTom on one of the other nets.

George

Cliff Rohrabacher
09-16-2008, 6:26 PM
The reason you want it all together with the same tension as it;ll have in use is because there is just no way you can contemplate the amount of deflection and spring back.

I used to make four slide dies for bending wire into complex geometries. We had to take the dies out and regrind them ( or make new ones) every time we bought a new run of wire because no two production runs of steel wire have the same spring back in them. And that's just steel wire on a spool.

How much more complicated will the cast body of a plane be?

I don't think the deflection is going to be a lot but, there will be deflection.

Johnny Kleso
09-16-2008, 7:45 PM
I have ground over a dozen planes at work before I became disabled..

I would have them grind it without out because with it in it will make it harder for them to hold and they could crack your plane while holding it..

Make sure to tell them its cast iron and prone to cracking if not held correct..

If you frog and frog seat is milled corectly it should not make a difference..

Todd Hyman
09-16-2008, 8:09 PM
I have a couple of planes that have been ground by probably the same gentleman Clint is speaking of and he does a fantastic job.

He goes by TablesawTom on one of the other nets.

George

George,

Can you tell me what other site TabelsawTom is on?

Thanks,
Todd

Bill Moser
09-16-2008, 8:16 PM
Pedro,
The finish off a surface grinder can look like a mirror if a fine grit wheel is used.

Joel,
How are they going to set up the plane for grinding? If they are going to "come off" the side of the plane, are the sides parallel? If not, and you are right-handed, then tell them to use the right side of the plane to make the bottom square to. This will make the plane usable in a shooting board.
I would also advise you to take a couple passes over some sandpaper placed on a flat surface (your tablesaw would work). Scribble some magic marker over the bottom first so you can see what the bottom looks like.
But, the very first thing *I* would do, is sharpen the blade and use it. Flatten a board, check with a straight edge, if flat - you are good to go.
Dont get so hung up on perfection that you never make anything. Fine furniture was made with much less sophisticated tools than the worst tools offered today.

It's wood, it moves, if you want to work in microns, take up metalwork.
Dont sweat the small stuff.
Nobody looks at a nice piece of woodwork and says: "Wow! what a flat plane you had!"
Mike

Joel -
i couldn't agree more with Mike. If you can joint an edge, or true a board, there's no point in making the plane surface any flatter than whatever it is now. If you're having problems with the plane, and it's not the blade or chipbreaker, then maybe sending it out is the answer, but I would consider it a last resort. I have a 6ft long Starrett staightedge that I use when I flatten my workbench. I have a pretty good system worked out, and I can get the bench to within < 2 thou with not too much effort. Is this the right thing to do? Well, my guess is what it goes back out of true in about 5 seconds. It's totally unnecessary, but I like to do it, so I do. I've also spent countless hours flattening plane soles, even when they appeared to be working fine. Not so much lately , though -- it's a lot of work!
cheers
bill

Tony Zaffuto
09-16-2008, 8:27 PM
I've got to agree with Rarebear. I've had one of my machinists grind a number of planes for me and the results have been terrific, however whoever does it has to know how to grind cast iron and how to fixture. If the frog fits well in the first place it shouldn't make a bit of difference if it is in or out. With it in is going to make fixturing much more difficult.

With a fine wheel you get a result and appearance that will rival a LN!

T.Z.

Joel Goodman
09-17-2008, 12:08 AM
Thanks for all the help!!

George Moore
09-17-2008, 9:12 AM
Todd,

Check your mail.

George

James Mittlefehldt
09-17-2008, 12:25 PM
But, the very first thing *I* would do, is sharpen the blade and use it. Flatten a board, check with a straight edge, if flat - you are good to go.
Dont get so hung up on perfection that you never make anything. Fine furniture was made with much less sophisticated tools than the worst tools offered today.

It's wood, it moves, if you want to work in microns, take up metalwork.
Dont sweat the small stuff.
Nobody looks at a nice piece of woodwork and says: "Wow! what a flat plane you had!"
Mike

Amen brother, could not agree more.

Later on revisit the thread Joel and let us know what you do and how it comes out.

philip marcou
09-19-2008, 4:49 AM
Joel,
How much is the plane "out" by? (It may not be necessary to go to the extreme of surface grinding ).
Any competent professional machine shop will recognise that the material is cast iron, fairly thin and will distort if improperly clamped. The plane will have to be held/clamped in the machine vice or otherwise presented securely on the machine magnetic table. This, together with ensuring that there is no distortion , is the responsibility of the machinist, who may decide to make suitable spacers to keep the sides from deflecting.
Your responsibility is to tell the operator exactly what you want ( e.g minimum material removal, sides square to sole etc).
I have experience of doing this work myself and you may be interested in knowing the sequence- the machinist may want to do it another way- but I grind the sole first, which is then used to reference the sides on. So the tricky bit is having the sole held "square " to the machine first, and this is set up by clocking (use of dial test indicators). The final side is done last and it does not need to be held in the machine vice -it merely goes straight onto the magnetic table and will be ground true to the first side-which itself was ground relative to the sole. So care in accurately setting up the sole for grinding pays off-and you pay for that setting up time. The actual grinding work time depends on the machine and the amount/number of passes needed to to true it all up. A typical depth of cut would be around 2 or three thou, with a cross feed of less than that to get a fine finish.
I have made various means to hold the work without undue clamping pressures-see pictures. Different planes, but you can see the sequence.
You should install the blade and chip breaker and tension the screw as in normal operation, but ensure that the blade is well retracted ofcourse (unless you want to grind the edge completely square with the sole :))

Alan DuBoff
09-19-2008, 3:16 PM
Philip,

Where's that drool emoticon, I can't find it...ok I'll use this one...:cool:

Folks like you are so much more of a machinist than myself, if I ever craft a hand plane that is half as stellar as the ones you make, I'll consider that a major accomplishment in my lifetime. :o

'course, I won't let that stop me from hacking one together...:D