What Makes a Bronze Plane better than a Cast Iron plane?

[Joe Beaulieu]

I recently saw a post on the LJ forum where a guy said he loved many of his hand tools, but the one that stood out the most was his bronze #4 LN Smoother. I own a bunch of LN and LV planes, as well as several Bedrock versions of Stanley planes, but I do not own a bronze bodied plane. I have seen people swear by them here and on other boards. Why? What is the appeal? Just curious.

Joe

[Patrick Chase]

I recently saw a post on the LJ forum where a guy said he loved many of his hand tools, but the one that stood out the most was his bronze #4 LN Smoother. I own a bunch of LN and LV planes, as well as several Bedrock versions of Stanley planes, but I do not own a bronze bodied plane. I have seen people swear by them here and on other boards. Why? What is the appeal? Just curious.

Joe

I think that the subject line of this post presupposes something that's actually open to debate, namely the assertion that bronze *is* better. In my opinion bronze is over-rated as a material for planes, and I say that as the owner of L-N #2, #8, and #10-1/2 planes. The #2 has a bronze casting, while the other 2 both have bronze frogs and lever caps.

Manganese-Bronze alloys like the one L-N uses have 3 major objective benefits, though the practical importance of each is open to debate:

1. Strength. IIRC L-N's alloy has about 2.5x higher yield strength than ductile iron. I personally don't think this matters - parts that carry cutting loads tend to be steel (which is stronger still), so IMO you don't gain all that much by having a stronger casting. Note that this would be most beneficial in larger planes, and yet L-N makes those with iron castings...

2. Density. L-N's alloy is about 15% more dense than cast ductile iron, so if you're one of those people who thinks that heavier planes are inherently better this might be perceived as an advantage.

3. Bronze is much more corrosion resistant. This is by far the most valid of the 3, though it's really not very hard to keep iron planes rust-free so even this is of somewhat limited benefit.

[steven c newman]

Wasn't there a reason why the Bronze Age ended when people started to forge iron.......?

[Tony Wilkins]

I think that the subject line of this post presupposes something that's actually open to debate, namely the assertion that bronze *is* better. In my opinion bronze is over-rated as a material for planes, and I say that as the owner of L-N #2, #8, and #10-1/2 planes. The #2 has a bronze casting, while the other 2 both have bronze frogs and lever caps.

Manganese-Bronze alloys like the one L-N uses have 3 major objective benefits, though the practical importance of each is open to debate:

1. Strength. IIRC L-N's alloy has about 2.5x higher yield strength than ductile iron. I personally don't think this matters - parts that carry cutting loads tend to be steel (which is stronger still), so IMO you don't gain all that much by having a stronger casting. Note that this would be most beneficial in larger planes, and yet L-N makes those with iron castings...

2. Density. L-N's alloy is about 15% more dense than cast ductile iron, so if you're one of those people who thinks that heavier planes are inherently better this might be perceived as an advantage.

3. Bronze is much more corrosion resistant. This is by far the most valid of the 3, though it's really not very hard to keep iron planes rust-free so even this is of somewhat limited benefit.

You forgot #4 - licking them to keep California law makers busy protecting us from all the evils of the world.

i have an LN bronze 4 and I do appreciate the weight as a smoother. If I drop it I might like your first point. Given the trouble I have keeping rust at bay on my LN 7 I do appreciate #3.

[Malcolm Schweizer]

Corrosion resistance, weight, and good looks; in that order. I'm not saying I care about the latter, but certainly a lot of folks do choose bronze for the look so I included that... Much the same with cocobolo totes versus cherry. 99% of the reason I choose bronze is for corrosion resistance. The other factors are added bonuses.

Patric Chase, I disagree on keeping iron planes rust free. I live in the tropics and would trade every plane for an equal in bronze if I could. Oh the time I would save in tool care. My bronze LN's live in the bench. The other planes live in plane socks in a drawer with camphor blocks. Periodically I have "plane tune-up day" where I remove light rust. I am sure folks up north that deal with hot to cold condensation would also disagree.

I prefer a heavy plane, and it does have its virtues when planing tough grain, but don't get me wrong- sharpness and setup are far more important than weight. Japanese and other wooden planes by comparison can be very lightweight and get amazing results, so I am not saying a plane HAS to be heavy, but I personally like a nice hefty plane. That said, it works on a bell curve and after a 4 or 4 1/2 the weight becomes too cumbersome, which I believe is part of the reason LN never made any bronze planes beyond the 4 1/2. I have heard that casting difficulties and cost are another reason.

I am am not into bling, but I would be telling a lie if I said I didn't occasionally just pick up one of my bronze LN planes and admire the beauty of it. It's not a part of the buying decision for me, but certainly a plus. I guess it is like my wife- I married her because she is kind, smart, caring, and an all-around great person and best friend, but she is also nice to look at. :-)

[Jim Koepke]

I own a bunch of LN and LV planes, as well as several Bedrock versions of Stanley planes, but I do not own a bronze bodied plane. I have seen people swear by them here and on other boards. Why? What is the appeal? Just curious.

Joe, I lived most of my years in different parts of the SF East Bay Area. Not a one of them had the humidity problems I have experienced here in the Pacific Northwest. Once or twice a year I need to take every plane off the shelf and wipe it down because of weather shifts causing lots of condensation on my tools. It is also hard on everything else. I have to scrape lichen off of the windshield wipers of the vehicles.

Otherwise what Malcolm said sums it up pretty good. There are a lot of folks living in wet areas.

Only one of my planes is bronze. It is the one from LN that is less expensive by a lot compared to an old one from Stanley.

jtk

[Pat Barry]

For the manufacturer, cost is certainly a major consideration. Cast steel is significantly less expensive than bronze. I think this is the single biggest reason that factories such as Stanley went to cast iron. This cost savings gets passed along to the consumer of course and helps to generate more sales. The downside of corrosion is left to the user to manage.

[Allan Speers]

#1: Because they're PURDY.

#2: Rust resistance.


Definitely i that order, and I'm not ashamed to say it. :)

[Chris Hachet]

#1: Because they're PURDY.

#2: Rust resistance.


Definitely i that order, and I'm not ashamed to say it. :)

Given that I spend several hours a week at my work bench, a little bench bling is not a bad thing, ya know.....!

[Chris Fournier]

Bronze has attributes which are different than Ductile CI, I don't consider it to be "better than" however. It is flashy and complements the other components of a handtool from an aesthetics standpoint.

[Zach Dillinger]

It's pretty.

[Patrick Chase]

Wasn't there a reason why the Bronze Age ended when people started to forge iron.......?

They didn't have 86x00 bronze back then, or else they might have waited another couple millenia to switch, until they figured out steel.

[Patrick Chase]

Joe, I lived most of my years in different parts of the SF East Bay Area. Not a one of them had the humidity problems I have experienced here in the Pacific Northwest. Once or twice a year I need to take every plane off the shelf and wipe it down because of weather shifts causing lots of condensation on my tools. It is also hard on everything else. I have to scrape lichen off of the windshield wipers of the vehicles.


You're exactly right. I live in the East Bay now, and before that I lived in San Diego (an even more rust-hostile climate, as hard as that may be to believe) for 24 years. There's a reason why you see a lot more rust-free classic cars around here. A long time ago I lived in the Portland area (Vancouver, WA) for several months for work, and I can understand why corrosion would be a much bigger problem there...

[Joe Tilson]

I have had a Stanley 102 for a while now, and like it. I bought the LN 102 a few months ago, and like it, but I always go to the Stanley because that LN is so nice just to look at, for now. I'm sure to get over it, but like Allan says,"they are just plain purdy". The feel is warmer too.

[john zulu]

I like bronze planes but it cost plenty. Here are a few reasons I bought it

1) Rust free
2) More weight.
3) Beauty ? When it is shiny.....

[Brian Loran]

I bought the bronze for the rust prevention but I have wished for years I bought the iron. I am not a fan of heavy planes and thinking more about it, the 4 is my most used plane, so it is easier to keep rust off it! Dang it. It is pretty though.

[Patrick Chase]

You forgot #4 - licking them to keep California law makers busy protecting us from all the evils of the world.

It wasn't the lawmakers - even they weren't THAT stupid. Prop 65 was a ballot proposition, and demonstrates convincingly why direct democracies tend to fail.

My favorite part is that the language of the proposition requires known-hazardous substances to carry prop 65 warnings, but doesn't prohibit you from just slapping prop 65 warnings on everything. That turns out to be the cheapest route to compliance for many manufacturers. Of course it makes the warnings even more useless than they already were, since there's now no way to tell which warnings are "real" (other than to read the MSDS carefully, which is exactly what you would do if Prop 65 had never passed).

[Patrick Chase]

I bought the bronze for the rust prevention but I have wished for years I bought the iron. I am not a fan of heavy planes and thinking more about it, the 4 is my most used plane, so it is easier to keep rust off it! Dang it. It is pretty though.

Out of curiosity, what do you do to prevent rust?

I think there may be a division here based on willingness to use "non-traditional" rust preventatives. Malcolm stated that he lives in the tropics but uses a very traditional solution of plane bags and camphor (the original "volatile corrosion inhibitor"), so I'm not surprised he has a preference for bronze.

In addition to living in a more friendly climate I use decidedly non-traditional rust preventatives: CRC 3-36, VCI capsules (the modern answer to camphor), VCI squares, dessicants where needed, etc. I also have 3' rolls of 2 different kinds of Daubert-Cromwell VCI paper (one polyethylene-backed, the other uncoated) and use those when storing anything that can rust. In other words, my lack of appreciation for bronze may be influenced by the fact that I'm pretty aggressive about corrosion to begin with. The CRC 3-36 in particular requires some care - I'm pretty careful about removing it from my smoothing planes before final pre-finishing passes.

[Jim Belair]

Isn't there a downside to the bronze in that it will also oxidize? Not "rust" like iron but "tarnish" such that the discoloration can rub off on light coloured woods?

[Patrick Chase]

Isn't there a downside to the bronze in that it will also oxidize? Not "rust" like iron but "tarnish" such that the discoloration can rub off on light coloured woods?

That's definitely a problem with aluminum (and is the big knock on the Stanley A-series planes). I don't think the passivating copper oxide layer on bronze sheds that easily, though.

[Tony Wilkins]

Isn't there a downside to the bronze in that it will also oxidize? Not "rust" like iron but "tarnish" such that the discoloration can rub off on light coloured woods?

Yes and I definitely get that with my LN 4.

[Jim Koepke]

Of course it makes the warnings even more useless than they already were, since there's now no way to tell which warnings are "real" (other than to read the MSDS carefully, which is exactly what you would do if Prop 65 had never passed).

Many people have no idea of such a thing as an MSDS. I am sure most people in forums such as this know of Material Safety Data Sheets.

If nothing else warning labels might lead people to see the cost of convenience may be harmful if we are not careful.

Of course laws can not fix stupid in cases such as when some fool thinks the alcohol in window cleaner is the same as the alcohol in beverages.

Where the warnings on the side of cigarette packages useless? People read them. Who knows, maybe when some average person sees a warning label they will take the time to read the directions before using a can of spray paint upwind of your car.

jtk

[Brian Loran]

My climate isn't too bad either (Dallas Texas). The tools that sit around collecting dust give me the most rust issues. Even tools in cabinets and tool chests because I am opening and closing the doors a lot so dust gets in there. If I am using a tool almost every day there isn't any dust settling on it and I am constantly wiping it with paraffin wax, jojoba oil or 3in1 oil.

I have not tried any non-traditional preventatives yet. I may look into some of the ones you mention for my tools that do not see much use. (hmmm... I may have too many tools... nah.)

[Patrick Chase]

Many people have no idea of such a thing as an MSDS. I am sure most people in forums such as this know of Material Safety Data Sheets.

If nothing else warning labels might lead people to see the cost of convenience may be harmful if we are not careful.

Of course laws can not fix stupid in cases such as when some fool thinks the alcohol in window cleaner is the same as the alcohol in beverages.

Where the warnings on the side of cigarette packages useless? People read them. Who knows, maybe when some average person sees a warning label they will take the time to read the directions before using a can of spray paint upwind of your car.

jtk

Going way OT, but I actually agree with you. My point wasn't that hazardous substances shouldn't be labeled - it was that Prop 65 was so badly bungled that the labels don't convey any information whatsoever, which leaves you right where you started.

The bigger problem is getting people to agree on what constitutes "hazardous enough" to need to be labeled. I would personally advocate the "aflatoxin rule": If it's less hazardous than a jar of peanut butter then it doesn't need a label. Of course lots of people would disagree when they discovered just how much is excluded that way...

[Patrick Chase]

Yes and I definitely get that with my LN 4.

Does "that" mean "tarnish" or "tarnish that visibly stains the wood"?

Tarnish definitely happens, but it's very much a positive feature of bronze. That thin layer of copper oxide passivizes the exterior (renders it chemically inert) and thereby prevents any further corrosion. That's sort of the entire point :-).

What I haven't seen is tarnish noticeably transferring to the workpiece. If so, what sort of wood was it? I would guess it would be both light-colored and abrasive...

[Pat Barry]

Does "that" mean "tarnish" or "tarnish that visibly stains the wood"?

Tarnish definitely happens, but it's very much a positive feature of bronze. That thin layer of copper oxide passivizes the exterior (renders it chemically inert) and thereby prevents any further corrosion. That's sort of the entire point :-).

What I haven't seen is tarnish noticeably transferring to the workpiece. If so, what sort of wood was it? I would guess it would be both light-colored and abrasive...
Getting pretty deep in the weeds here. Does the rust from a cast iron plane end up embedded in the wood fibers?

[Niels Cosman]

None of the rust, all of the sexy! :D

[John Sanford]

As stated previously, bronze is pretty. Note that bronze is still used in a lot of machinery and such for bushings. It's a bit heavier. And, it's, in a sense, "exotic". Bronze is not really a material that we encounter frequently in our daily lives. Steel, and to a lesser extent, cast iron, is everywhere. (Most folks don't really differentiate between steel and CI).

As also stated previously, bronze and ductile CI have very different practical oxidation considerations. Bronze tarnishes. Slowly. CI rusts, as quickly as the environment will allow. I've been fortunate to live most of my woodworking life in places where a plane could have been left outside 80 years ago, and aside from totes/knobs that crumble at a touch from extreme UV degradation, rehabbing involves removing some light surface rust.

Theoretically, bronze and ductile CI have different coefficients of friction.

Basically, if you're attempting to decide between a bronze LN or a comparable CI plane, and rust isn't a major concern for you, just get whichever floats your boat. This is a hobby for most. If it isn't a hobby for you, then put on your figurin' and tallyin' hat and calculate your ROI. Note that a shiny bronze plane where the customer can see it may have more marketing value than a CI plane, especially if it's shadowboxed/lit up in a display like fine jewelry.

For both a bronze and CI plane, the business end is still going to be O2/A2/?? steel.

[Chris Fournier]

There's nothing sexy about my bronze 102s. They are tarnished here and there and look like they've been fished out of a pond except where they have been handled recently. I would never polish a handplane for vanity's sake, I simply wax the soles and sharpen blades. A bit of lube on the adjuster during a blue moon. Bronze is pretty but for me only when the plane comes out of the box when new!

[Patrick Chase]

Getting pretty deep in the weeds here. Does the rust from a cast iron plane end up embedded in the wood fibers?

:)

Indeed. My point was really that not all oxidation is bad. In the case of bronze the Copper-oxide patina is actually what prevents other/further corrosion. Unless your plane is a conversation piece or the tarnish is actually transferring to the wood (which I doubt) you should be happy it's there and leave it alone.

[Joe Beaulieu]

Hey Everyone - great information. Thanks. I knew the rust preventative advantage, but I don't get the beauty thing. Sorry, seems like a lot of guys like bronze for the look but I will take a shiny smooth C/I surface over bronze. I know bronze will stay looking new much longer than a C/I plane, but that moment you take it out of the box and it is pristine is really a kicker for me. Bronze just doesn't have that same impact. Just my opinion - and I guess I am in the minority. But I do very much understand the rust prevention thing. I am not a California native. I moved here from Massachusetts about 15 years ago. I can tell you that my planes were paid much more attention to back east as well as my table saw, jointer, band saw, drill press beds and any other C/I surfaces. The high humidity in the summers in Boston was really tough on tools. Another advantage of living in the Bay Area, I guess I need to be thankful for that. California is a pretty nice place to live. Except I miss my basement. I had to compress my shop into my 2 car garage here, where I had a 950 sq ft 8' high ceiling clear basement back in Massachusetts. I loved my basement - I would really like to have one again.

JB

Anyway - enough of a rant. Thanks guys - I really do appreciate the help. I was thinking of buying a #4 in bronze. Maybe I will just to have one. I have the LN 41/2 in C/I obviously, and I love that plane.

[Jim Koepke]

Except I miss my basement.

Most houses in the bay area with basements call it a rental or a family room.

jtk

[george wilson]

Actually,though I have made many things from brass and bronze,I also like a finely ground cast iron plane. It's hard to quantify: Some things look to me better in brass,some better in cast iron or steel.

That NX60 LV block plane I have is interesting; it is made of a high nickel alloy of cast iron that looks nickel plated,but is solid all the way through. I like its looks on that block plane though it is slippery to hold on to.

[Glenn Kramer]

I own most of the LN line of planes. I prefer the bronze for additional weight, lower maintenance, better feel (to me) and they sure look great in a nice tool cabinet. I have also sold a few LN planes in the past. Bronze definitely has a better resale value, not sure why. The LN 4 smoother is an awesome tool in either material.

[Patrick Chase]

This may seem nit-picky, but...



As also stated previously, bronze and ductile CI have very different practical oxidation considerations. Bronze tarnishes. Slowly. CI rusts, as quickly as the environment will allow.

Actually Bronze tarnishes a little bit and then stops, as long as you don't do something silly like removing the tarnish. As I've already said, that's exactly what makes Bronze so good in terms of corrosion resistance.