The need for a compressor to use with a pneumatic die grinder might be the determining factor. Take a look at your die grinder’s air requirement and it might require something like 20.cfm @90psi for continuous duty. That’s beyond the capabilities of a small compressor. But you might be able to use the die grinder for short bursts.
Over on the main Toolguyd site - Stuart is posting about Black Friday deals - some include compressors - but these are more aligned for use in light construction applications (like nail guns) - not for use with pneumatic tools like grinders and sanders that tend to be air hogs.
To fred’s point the die grinder and the air sprayer sort of dictate your needs. I suspect the air paint sprayer might actually want more air volume as I’m assuming you want to use a HVLP gun for finish and control. between that and the die grinder I think you’d find you want something more in the 8gallon range for the duty time and some overhead. maybe 6.
That rules out something like a 6 gallon pancake device.
SO what you could do is pick one of those items to move electric. Example - today there are electric HVLP sprayer systems that work great. I know a guy that painted an impala with one - yes an entire 68 impala. They even make a cordless device I think it’s Graco.
Meanwhile there are very good electric and even cordless die grinders. So you could use a pancake compressor for your airing up tasks and later run a nailer/stapler/etc off it. while using electric to run your sprayer and die grinder. Or flip flop that and get a sizeable air compressor and then use a battery tire inflator for one of the cordless options. I personally like the dewalt model.
I don’t use pneumatic tools, but I recall an article in Fine Woodworking some years ago about using a large auxiliary air tank to get more working time out of a small compressor. The compressor pumps the big tank full of compressed air (and that might take a while at first), then you run your tools off the big tank, which is topped off as needed by the compressor. Continuous use will drain the tank of course and outrun your compressor, but you will be able to work longer. The idea is that tanks are cheap, while burly compressors are expensive.
Speaking of which, it always puzzled me why compressors are described by the size of the tank, and not something like rates of compressed air delivery (at some specified pressure) or just horsepower. I know the tank affects portability, but if a compressor doesn’t deliver enough air, then it won’t do the job. Am I missing something?
Would the Husky 20 gallon be a viable option to do everything? Doesn’t seem too too big and the price is right compared to so many of the smaller offerings.
They are described as both. nearly every air compressor is also rated with PSI @ X flowrate. Which is a measure of power. Flowrate is often in CFM but some are setup as metric and KPa x CMPM or L/M
anyway yes you could buy another tank to set and fil both in series however compressors come in so many sizes and setups now that it’s not as cheap an option as it used to be. Often it’s cheaper to buy a bigger sized compressor for the job.
However as I mention many air tools are not running as electric or even cordless as the efficiency has gotten better.