How many purgers should I stockpile before scanning WITHOUT upgrading scanners? 100?

Depends... How many planets do you have scanned now? What is your max scan?

I have 525 planets and scan around 8000. 100 doesn't do enough for me, I need about 400 to completely refresh my database.

A lower rank player with 150 planets and max 1000 scan could probably get by with 75 or so.

It really depends , I think 100 is a good # it lets me do a scan every 20-30 days , but If you sell you're scan mods after a scan blitz then you may want to save up some more to make up for the cost of rebuilding them.

Tachycon sensors at the moment, with 276 planets scanned.

I would upgrade my sensors, but I have so much else to research, like +8 (which I'm behind on) Isomorphic Entanglement (again, should be done already) and Null Rays (meh, not so behind, but meanas I have builder now)

where would you like your chance of scanning to sit?
Good (70-100%) ?
Fair (40-70%) ?
Poor (15-40%) ?
Very Poor (under 15%) ?

also... will you be purging planets you don't want the immediate moment you find them during your scan blitz?

Purge as many as possible beforehand. If I have any spare purgers then I would purge-as-I-go.

And good would be good.

1 can say for definate with a scan of 1700-1760 once you hit 130-132 planets it turns from good to fair and with a scan of over 2k then you need around 170 ish area to hit fair(didnt notice the number when i did the run) purging at a low level is a pain in the rear end tho as dont get many purgers have managed to drop back down to around 130 slowly but surely but means for the tech i have i have to wait way longer

not sure if anyone else has kept track of numbers that rating changed but those are the 2 i remember as most recent runs

i don't bother recording anything that is more than a 30 scan gap at a fixed planet # or anything more than 1 planet at a fixed scan #

Hmm. I've been using purgers as I get them, and only running scan blitzes when I finish researching new scanners. Advantage to this is that I don't have to keep the purgers in inventory and I'm not wasting energy on purging when I scan. The only blitz I was at all disappointed with was the latest one, from X-Manifolds.

As a rule, I purge everything less than Rich and less than Very Large from my database before I do a scan run, however many scanners that takes.

Well I went and did it at 43 purgers. Got a good rating, but only for a few planets. I did find some gooduns though, so all is well. I'd say from 40 planets scanned, I got 5 good ones which is REALLY lucky and that includes a VM/MR with an omnibase.