lead in planer knives?

[psychicrhino]

A few years ago I bought a few pallets of scrap from a sawmill that closed down. Amongst the stuff was a whol slough of industrial planer knives. They have tabs on them that look like lead and are dentable but only with a hammer. I can shave it with a sharp pocket knife but it is hard. Any ideas what this might be?

[psychicrhino]

Could it be a babbitt material? If so, anyway to determine the composition.

[JonB_in_Glencoe]

Melting temperature and hardness and weight of a cast boolit from a "known" weight boolit mold, will give you a clue.

[bangerjim]

Could be babbit. Could be Zinc. Could be just about any alloy. Only melting temp and casting/weighing some will sort of tell. A drop of muriatic acid (pool acid) will bubble up if it is Zn....good test for that.

You could take an ingot of it to a scrap yard that has an xray gun and find out exactly what it is!

Zn. Babbit, and all alloys of lead will cut (to some degree) with a knife, so that is not a good test.

Best bet is to hope someone on here works or used to work around a mill and will know what they used!

Let us know.

banger

[Pepe Ray]

I have samples of identical pieces, also from planer blades .Also chipper knives. If the source is from a time frame in the recent, say 15-20 years , it will be a lead free babbit. Actual % of tin could vary but will be high.
When my employment shut down I negotiated the release of one of the lead pots full of babbit. Great stuff when you wish to harden up your alloy.
I can give no further advice than to experiment w/it.
Pepe Ray

[Ubet]

I used to work in a sawmill years in Montana, with my dad. He was foreman on the planer crew. I remember they had a melting pot of babbitt that they used in casting those for the planer knives.

[psychicrhino]

Good advice everyone. I think I have some muratic acid somewhere in the shed. Had gotten it to clean a sidewalk before selling a house. Good point about tge melting point, will start looking for a little pot to use in case it is zinc so I dont have it in my lead pot. I probably got the knives about 5 years ago from a mill that closed about that time. They were in a big lot of chains, and bolts which is what I really wanted. The blades were all sharp, just had no need for them. Tried to sell them back then but had no takers. Stumbled across one and got to thinking. When I do get some melted I will try casting a few just to see about the wt. Thanks again.

[Ubet]

If you have friends that make knives you might talk to them. The steel from the planer knives could make some great knife blanks.

[bangerjim]

That all makes sense it is Babbitt. It was VERY popular in years past for bearings and casting things in place, like those planer blades! My Dad used to tell me how they would cast new Babbitt bearings for a lot of the machinery around the power plant he used to be a mechanic in. That was back when ball bearings were all going to WWII efforts and were next to impossible to find.

My 1st metal lathe had Babbitt headstock bearings. When they wore past the point of adjusting the mountings, you just poured new ones!!!!! Being soft compared to the steel headstock, they "wore" in place very fast and offered very good bearing surfaces, as long as you kept them drenched in oil!!!!!

Today I have no idea what modern industry would want with Babbitt. Ball bearings are so cheap (Japan & China) you can pop them out and put new ones in in nothing flat.

Glad you found some guys on here that were familiar with mills and the tools therein!

banger

[psychicrhino]

Found a neat writeup here about babbit for bullets as well as tin vs lead based. Talks about how to seperate any copper content and how to alloy with it.

http://www.lasc.us/FelixBabbitbulletAlloy.htm

[psychicrhino]

Well, I went to look at the pile of these blades I have and found one with a logo on it. Not sure what it says other than "made in finland".

[psychicrhino]

Several different types and ages of blades.

[psychicrhino]

Picked two difft styles and broke some tabs off. One type seemed to have more od a grainy or sandy structure (like fractured cast iron) whete broken. The other was mor crystaline (like frost on a glass).

[psychicrhino]

Placed a half cap of muratic acid on both samples. I did not prep or file the samples. As you can see, one reacted significantly with bubbles. The other just sat on the surface like water, but on close inspection some very tiny bubbles were noted. Both samples had the muratic acid applied at the same time. Are both zinc? Any ideas now about the structure at the fractures?

[Pepe Ray]

If they came from the same mill you can be sure that the alloy is the same, regardless of how they look at breakage.
Do not be concerned with the presence of Cu in the mix. It would be detrimental ONLY if you were exclusively a black powder loader/shooter.
Pepe Ray

[bangerjim]

Placed a half cap of muratic acid on both samples. I did not prep or file the samples. As you can see, one reacted significantly with bubbles. The other just sat on the surface like water, but on close inspection some very tiny bubbles were noted. Both samples had the muratic acid applied at the same time. Are both zinc? Any ideas now about the structure at the fractures?

Bubbles are not good. Indicative of Zn or other non-wanted metal in there....at least for boolit making.

Take a look at Roto's site for standard Babbitt:

http://www.rotometals.com/Babbit-Bearing-Alloys-s/2.htm

None of the metals in standard alloys of Babbitt should react like that with HCl.

The only way to eliminate all guesswork (what you are doing right now) and REALLY know is to have a scrap yard shoot an ingot of the stuff with their xray gun. That will tell you exactly what is in there. Many will do it for free......some will charge you a nominal fee to use their $45,000 toy!

banger

[psychicrhino]

So, the logo helped me find a manufacturer.

http://www.ttt.fi/page.php?page_id=76

Many of the blades look new, others are obviously used. Tge lunk above sats they recindition blades as well as sell new. Of the two samples I present above they also look difft on the outside of the tabs. Sime look like leas that was pored a little cold into an ingot mold - kind of wrinkled, like hot was poured on cold medal, kinda like soft serve ice cream. The other tabs have markings that show they were machine ground after poring. The exterior surfaces are more uniform. I really think they may be difft alloys. So I was hoping they were a mostly tin based babbit, I assume the vigorous reaction with the one sample to the muratuc acid means zinc?

[psychicrhino]

You were postung while I was typing, thanks. Kind of what I thought.

[psychicrhino]

Well, I was wondering if the acid may have reacted to surface contamination. I broke out the grinder and took two new samples down to bare metal. Yielded similar results to the pics above. I guess I will abandon these as they appear to be zinc bearing. Thanks for all the good suggestions.

[mold maker]

Are you saying that, after cleaning to bare metal, they both fizzed with the acid, indicating zinc?
Reguardless the material has value. We have cannon ballt casters that love zinc. At least one here trades lead for zinc.
As scrap zinc and lead are about equal value.
You can't economically separate zinc from a lead alloy, but a very small amount isn't a deal breaker. Some are actually using zinc to harden alloys. While I have no personal knowledge of it. I have a friend that has done successful experiments with it.