This is a great idea in many ways-I can tell my wife that I'm out 'testing mugs'!

I'm on t-shirt forum as well, and getting great advice from both!

Does anyone know of an effective low-tech way I can test my mugs for this issue before I put them out for sale? Apparently boiling water isn't enough.

Thanks for all the replies and info!
I don't print these my self, but I do sell enough to buy a gross at a time. Can any of you recommend a printer in the US that could do these for under $3 per piece?

I'm not sure about the 'hand wash'. I never got to see it. I can tell dishwasher damage because it bleeds as a flow.

I don't understand why they were OK before. I poured hot boiling hot water on the first image you see, and I wasn't able to bleed it further.
Is there a type of coating I should be aware of or asking for?

<t>Hi-<br/>
I have been selling my "Greetings from Hoboken" coffee mugs (and related merch) for years. I buy them from a large online vendor and they've always responded well to any issues.<br/>
Recently, I've had about 5 customers complain about the mugs bleeding after being put in a dishwasher ...