PDA

View Full Version : RotoMetals Popcorn Tin - BE CAREFUL!!



Foto Joe
02-05-2014, 02:37 PM
Since I started adding 2% tin to my COWW lead I've been on the search for inexpensive tin. I know, I know, there's more than a couple of you who are going to advise me to find cheap pewter but I just don't want to go around scrounging for an unknown. 97/3, 64/40 etc. solder is a convenient source if you don't mind getting nailed $40 per pound for tin but after using 97/3 to get myself familiarized with adding tin I needed to find a different source than the local Ace Hardware. This of course led me to RotoMetals and through them a new product that they have that they call Popcorn Tin. I ordered a couple of pounds a few weeks ago ($20 per lb) and have since run through about a pound of it. Here's what I think....

The big advantage to the Popcorn Tin is that it weighs well on a small digital powder scale and you can hit your exact weights easily simply by adding tiny pieces of the product. There isn't any need to error on the side of too much tin since it's so easy to weigh. The price is about a dollar a pound more than their cut wire tin. For the ease of weighing I think the buck a pound is probably worth it but there is a SERIOUS down side that I found.

I don't know for sure but I might venture to guess that they make their Popcorn Tin by water dropping molten tin. To me that's what the finished product looks like at least. As you might have already guessed, there is the possibility of trapped water in those little popcorn kernels of tin. So far after using almost the first pound of Popcorn Tin I've encountered two pretty substantial bangs when adding it to molten lead. As of yet I haven't had a notable visit from the Tinsel Fairy but I'm more than a little sketchy when adding to molten lead. Of course the quick answer if using this product is to NOT add it to molten alloy but when the pot is low and you want to keep going it's a pain to let everything cool off, solidify and start over.

I'm posting this for informational purposes, if there's any of you out there who are using Popcorn Tin I'd like to know if you've had similar experience with it. If you're not using it and are thinking about it just be aware that it appears that it "can" harbor some trapped moisture that could lead to surprises.

bhn22
02-05-2014, 03:17 PM
You're paying $40.00/lb for 95/5 leadfree solder? That's double what it is around here.

Digital Dan
02-05-2014, 03:28 PM
Walters' Wads Vegetable wads, tin, & lead alloy. John Walters 500 N. Avery Drive Moore, OK 73160 (405)799-0376.

Get in touch, john has lower prices and better service than anyone I've met.

williamwaco
02-05-2014, 03:39 PM
There won't be any water in this:

http://www.rotometals.com/product-p/tinhighgradepcs.htm

$19.00 per pound AND Shipping is free on orders of $100.00

Frozone
02-05-2014, 03:48 PM
Darn! My last tin purchase was $10 /lb. and not That long ago.

Good thing I bought 10# :-)

I posted this before but it bears repeating.
I use cylinders and balls of tin.
I bored out an old worn out LEE 2 hole mold with a 1/2" bit - it drops a 15 gram cylinder.
I also cast up .451 round ball - 5 grams each.

Since 5 pound is ~ 2270 grams it's easy to mix and match to get the percentage you want to around 0.1%

Foto Joe
02-05-2014, 05:00 PM
That tin wire that williamwaco referenced on the link is probably what I'll do from now on. If not that I'll check out the number that Digital Dan put up. For now I've got enough to do more lead than I've actually got on hand and I've got quite a good supply of boolits cast.

R.M.
02-05-2014, 05:39 PM
The simple solution would be to pre-heat it.

Nrut
02-05-2014, 05:43 PM
Foto Joe,

Glad you posted your experience, but I am wondering why didn't you call or e-mail Rotometals and ask them if they water dropped their tin popcorn instead of just guessing??

If there is a problem with their product I would think they would like to hear about it..

southpaw
02-05-2014, 05:53 PM
I do things a little different. I like to make large batches (100-200#'s ) of a mix that way I don't have to mix in the casting pot. This way I can just put some lead in the pot and go. I like to keep ingots on the preheater and just add them as I go.

Jerry Jr.

cs86
02-05-2014, 06:00 PM
Thanks for posting. I was looking at the popcorn and wire cut tin for future purchases of tin.

DRNurse1
02-05-2014, 06:05 PM
South Paw has a good idea: bigger ingots when smelting a batch of found stuff, then mix and match into a batch of alloy for run in your casting furnace. I have tried this and it seems to work for me.

Folks get on about smelting twice, but some of my bigger ingots have been sitting around a while and I need to get the dust off them.

I have a set of letter dies to strike the content on the ingots, too. Got them for labeling leather work years ago but they work fine on ingots, too.

BTW: isn't NEPA in the Northeast, South---paw?

southpaw
02-05-2014, 08:11 PM
BTW: isn't NEPA in the Northeast, South---paw?

Yup. Northeast Pa. We got a little bit of snow today. About 10-12", I haven't had a chance to get a measurement yet.

Jerry Jr.

quilbilly
02-05-2014, 11:52 PM
If you are not using that much tin (1/2 oz here or there), you can always go to Walmart and get their lead free tin splitshot sinkers in the fishing tackle section. A couple size 4's is usually enough for a pound of pure or WW. Not the cheapest way to go but they make precisely measuring easy.

Slow Elk 45/70
02-06-2014, 04:30 AM
guilbilly, good info , that many of us {me} had not thought of !!! Thank You for posting...

Ajax
02-06-2014, 07:10 AM
If you watch in spring and in the fall they put all that stuff on sale. ;-)

Andy

Foto Joe
02-06-2014, 10:16 AM
I'd almost be afraid that "Lead Free" sinkers would be zinc, are they labeled as tin? Although I don't go through a lot of tin I do usually wind up adding between 1.5 and 2.0 ounces at a time.

As far as adding the tin during smelting, it's just not for me. I use only one alloy (other than soft for Black Powder) so the pot always has the same stuff in it. If I add the tin when I add lead then I can weigh it in exactly and not have too much or too little. If I did it when I was smelting I'd have to use the S.W.A.G. method to calculate how much tin I needed to add. I've got a buddy that does it that way and he has a tendency to over do it. Also, I think that my days of smelting down wheel weights are pretty much at an end. Given what I have to pay for the things in the first place at home in Wyoming then the sorting, smelting etc. I've found that I can buy the stuff almost as cheap as I can do it myself and sometimes cheaper.

I think it depends upon what part of the country you're in but up north it costs me at least $70 for a bucket of wheel weights that are 15%-20% steel and zinc. My finished price usually ends up somewhere around $1.40-$1.50 per pound. Keeping that in mind, I found a week or so ago COWW lead on eBay for $1.67 per pound including shipping for 60 pounds. I realize that I can get dinged on eBay pretty easy but after looking at the sellers rating I felt pretty confident that the stuff was as advertised. I haven't tested the hardness yet but I'm guessing it will run out at 11-12 BHN just like the stuff that I smelt.

southpaw
02-06-2014, 11:28 AM
I'd almost be afraid that "Lead Free" sinkers would be zinc, are they labeled as tin?


As far as adding the tin during smelting, it's just not for me.

Yes they are. I just pick mine up when I am fishing for salmon in pulaski, ny. They can't sell lead sinkers up there but, so far, it is still legal to use lead.

Add the tin in a separate smelt. Smelt the ww and or pure and ingotize them. Weigh out what you want your mix to be and remelt, ingotize and label. Works better when you can 100 pounds or more at a time. Less variation than if you do it 10 pounds at a time and now you have 100 pounds or more of the same alloy.

Jerry Jr.

deltaenterprizes
02-06-2014, 12:00 PM
Put the popcorn tin in first and then add other metals