Cupped Plane Iron

[Cory Waldrop]

Hey guys just wanted to get your thoughts on something. I purchased a plane recently and when I was working on flattening the back of the plane iron I noticed It was only sharpening on the two outside edges and only about 3/16 in from each edge. As I was using a coarse-ish diamond stone, I was surprised that It was only hitting on those small areas. So I grabbed a straight edge and sighted along the blade and noticed the whole blade was cupped even out to the cutting edge. Major bummer. My first thought was maybe I could just suck it up and flatten the thing anyway, but then I thought as soon as I install the chip breaker, it is going to straighten that blade out and then I will have a cupped cutting edge going the other way.... So I decided to return the plane for an exchange instead of chasing my tail.

So my question is.... would you have done the same? I know a small hollow is pretty normal for chisels and plane blades, but if the iron is cupped the whole length, it seems like a defect to me.

[David Weaver]

It's a defect. If you can't get out whatever it is reasonably quickly with a coarse diamond stone, then you need to get an iron that isn't like that and start over.

[glenn bradley]

What David said. If we continue to accept poor quality, we will continue to get it. You are actually doing the maker a service by letting them know that they have to do a bit better to get your business.

[Frederick Skelly]

Its a defect. Id return it as you did. If its a quality brand, the next blade will be right. If its an inexpensive brand the replacement may be no better and youll have to decide your next step (eg, return again, replace yourself). Ive seen it go both ways.

Just for your hip pocket: Some big box stores carry a Buck Brothers 2" wide blade that works well enough in my #5 after a bit of flattening. They cost about $3. So if the replacement still cups and you can use a 2" iron, you dont necessarily have to spend $50 or fight it out with the vendor.

Good luck!
Fred

[Roy Lindberry]

Hey guys just wanted to get your thoughts on something. I purchased a plane recently and when I was working on flattening the back of the plane iron I noticed It was only sharpening on the two outside edges and only about 3/16 in from each edge. As I was using a coarse-ish diamond stone, I was surprised that It was only hitting on those small areas. So I grabbed a straight edge and sighted along the blade and noticed the whole blade was cupped even out to the cutting edge. Major bummer. My first thought was maybe I could just suck it up and flatten the thing anyway, but then I thought as soon as I install the chip breaker, it is going to straighten that blade out and then I will have a cupped cutting edge going the other way.... So I decided to return the plane for an exchange instead of chasing my tail.

So my question is.... would you have done the same? I know a small hollow is pretty normal for chisels and plane blades, but if the iron is cupped the whole length, it seems like a defect to me.

I think you did the right thing. If the replacement is no better, and you don't want to go through the hassle, you might check to see how much flatter the iron is with the chip breaker installed. If it flattens out, there remains the possibility of sharpening with the chip breaker on. Put it little further from the cutting edge than normal, sharpen the bevel, and wipe the burr on the back side.

This is by no means a preferred practice for me, but if I was simply trying to get some use out of an inexpensive tool it would be an option. I would never accept having to do this if I was dealing with Lie-Neilsen or Veritas. They will make things right. But if you're dealing with a box store brand or something, you may never get the quality you want.

[Cory Waldrop]

Thanks for the replies. I have a replacement on the way and hopefully the new plane doesn't have the same problem.