Mailing coins reliably and cheaply

I have about 2500 Lincoln cents to disperse. 

First, is coming up with a mailer in which the coins are not detectable. What I've come up with is using 1/8" foam packing material. I made a punch and die for the Lincoln cents.

This failed initially, until I realized the tolerances between punch and die are much closer for foam. Using a sacrificial cardboard backing worked fine.

The next consideration is weight. My goal is to mail 7 US pennies by 1st class postage. One concern is that under hard usage, coins could be jarred loose and float. A paper sleeve adds enough weight to exceed 28 grams. 

So I've tried to redesign the #6 ¾ envelope to reduce weight.

All a work in progress. Any input from collector- machinists is most welcome! 

For some reason, I've not been able to get on Numista. This time it worked. 

After a little number crunching using the USPS calculator, the most economical is to use a standard envelope 2 oz. weight. I can get an extra ounce (8 coins) for $0.29. 

Internationally, there isn't any weight advantage. 1 ounce is $1.70; 2 ounces are $3.40. I used the UK as destination. I was a little surprised to find that Canada is considered international. I remember sending letters to family and friends at slightly above domestic rates.

spauldingph

I was a little surprised to find that Canada is considered international.

You’ll have to wait for Taco the Clown to annex them 😉

Perhaps. But I know Canadians well enough to know that the response is more likely to be a boycott of American goods. They are a loyal folk, as proven from the past. But I'd rather discuss golf than politics.  (Apologies to my few golfing friends).