Good morning, I have been to a few sales and I was wondering if it is no secret
how do you clean the grease from the pelt? Some are clean and no grease on the hair
and others are well you know thanks for any information

I believe what you're asking is, why some have grease and others don't, it's how they were scraped to start with, and weather they were wipe after they dry some.

Start with a dry pelt and keep the board clean

Don't stack them until all the grease has been wiped off the hides, and then stack them hide to hide and fur to fur.

If you have some spotty greasy spots around the edges some fine sawdust & a bristle brush will take of it

You mean off the actual fur, or just a greasy hide side? My buddies first one was terribly greasy but the fur was beauty. He fleshes over a beam. I've never really had greasy fur, but I flesh over my leg. Clean boards, lifting the hide up to the top of the nails, and brushing the fur to get the odd little bits of fat off near the edges after I pull it off the board.
If the furs greasy, I’d think it came from fleshing off a beam, when I tried it there was grease dripping off everywhere.

I guess I need to clarify what I am asking some looks like they have been washed
the fur side is clean the flesh side is also clean
So do they wash the hides after fleshing I have seen where they rub sawdust on the flesh
side then flesh I hope this makes sense

ill wipe down the hides with laquer thinner if theres some "sweating" on the leather side. Just pour some on a rag and wipe the hide down. Do this in a well ventilated area.

Don’t do beaver, but just wondering if Borax can be used on Beaver. I know it helps with grease on a badger.

Dont need to borax beaver hides. Maybe to help clean up the fur side

I clean skin but when I board it I run over the pelt with a paint scraper and pull any little tidbits of fat off and pull out any liquid grease or blood on/in the leather. Also, something I learned to do a long time ago is after the first 8 nails I run the scraper along the rim of the pelt so I get any fat that is there. When I de-board them I do a quick wipe down with paper towels on the leather side to pick up any beads of grease that have appeared. Brush or comb the fur side then stack leather to leather. I never have any greasy beaver pelts.

One other mention, when clean skinning I am able to shave down some of the fatty areas of the pelt such as the shoulders and tail area. This removes potential grease sources.

15 minutes in a real fur tumbler before fleshing makes a huge difference in the appearance of beaver.

Would like to hear more about this. Why tumble before fleshing? What type of media?

Probably overkill for the felt market, but there is some truth in that well presented fur always seems to command the best price.

Following

Scraping a bunch of beaver on a greasy old beam will get the fur greasy.
Clean skinning leaves the fur grease free.
To get the leather side grease free do like Beaverpeeler said

I saw a video of a guy that converted a old dryer and he tumbled rough skinned beaver in hardwood sawdust
then fleshed them it looked like they turned out good

Kinda hard to tell how heavy the under fur is when the guard hairs are is greasy.

you don't clean your beam after fleshing each beaver? In fact I will take a rag and get a bit of grease on It and wipe down that fur to give It a bit of a shine.

Probably, but true overkill is still laundering my coyote in that market, but I can't help myself. They just look so much better when done right.