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It took a long time to find my first comco blaster, and it's been a couple years since, but I finally found another auction, 2 in fact. I wanted 1 more for a second prep station, but I couldn't pass up a good deal. So now I need to open them up, clean, and replace anything worn out. Glad I already learned how to overhaul these from my first blaster. I plan on selling one of these after I'm sure it's in good working order.

I have been trying my hand at prepping for a few months now. Started with some nice air scribes, then tried air abrasion. I bought a cheap badger airbrush and threw tons of media at fossils. To me, it seemed that no matter what the pressure or sand agent, I saw absolutely no results. So, I bought a AEC and had it overnighted, hoping I was just using the wrong tool. Well, absolutely I was using the wrong tool. The moment I got the AEC up and running, I finally understood why it's called an air eraser. Slowly, but surely, the tough dolemite matrix melted away, as if it was being miraculously erased. HOTDOG! I thought these calymenid trilos I found in Kentucky were gonna be a wash...but dag nabbit, the details are coming out! This isn't the final prep, and I don't have any before prep pics, but this is a huge improvement. This trilo was just showing 1/4 of one side of its body. I didn't even know if it was fully intact...sure is! Even pulled out both the eyes. Super stoked guys. Level up-points into prep skill. BAM

I finished the dust collection system in my prep station this morning so I had to put the tools to use and start practicing! In a nutshell, I LOVE AIR TOOLS!! I picked out one of my random BOBs collected over the years from the South Dakota Hell Creek fm. Typical of my digs, this one had a lot of surface CA and matrix adhering to it, but it was about as clean as I could get it by hand.. I started out by cleaning half of it with just the soda blaster. You can see in the picture that it was doing a phenomenal job. I wanted to get a pic that showed the condition before I worked over the entire piece (in case I ruined it LOL). OF course there were some spots that just wouldnt budge. So I started using the air scribe. So amazing! Watching those little stubborn spots and every other bit of matrix just blow away from the tiniest touch of the stylus. I left the associated bone bit attached with its matrix just because. It looks to be from a different animal, possibly some type of theropod as those often have the hard, shiny surfaces. Trying to clean out the exposed marrow was the most challenging. Lots of tiny flakes of it came off during cleaning, but to just look at the fossil you wouldnt know. One thing I did notice was that the media blaster can eat though a lot of soda in a short time! I finished out the piece by conserving it with a coat of PVA.

About a month ago I went to Penn with two fossil buddies and they both found prone greenops. Sadly I did not find one. However both of these greenops were split between the positive and negative and probably were missing some skin as the material was quite flaky. For one of my friends this was his first ever find of a prone greenops. Prone greenops that are nicely laid out are a very rare find in the Windom shale. Most of the ones I have found from there or others that I have prepped for people are fully, partially enrolled or distorted. So to my fossil buddy this was a bit of a special find. We wrapped up the two pieces in tin foil in the field and I agreed to take it with me and prep it for him. Well zoom ahead a month in time and I am going out with him last week to collect and he asks how is his greenops coming, whereby I realize that I have not only not started it ,but in my senility had forgotten I had it and had no clue where it was. Well when I got home it turns out that I had never unpacked the bucket of fossils from that trip and low and behold his fossil was packed just as we had left it. A careful look at both parts under the scope confirmed my opinion that the bug was in pretty rough shape , but a prone greenops, not to mention perhaps his first ever prone warranted we attempt to bring it back to life. Unfortunately I did not take any pics until a ways into the prep but here is what I did to start. 1. Washed the mud off both plates scrubbing with a tooth brush 2. Squared up what would become the fossil plate with the diamond gas saw 3. Cut out as small as possible a square from the top piece of the matrix that contained the top part of the greenops using my 7 inch tile saw with diamond blade 4. On a belt sander using aluminum oxide 120 grit thinned the top piece as much as safely possible to help minimize my prep time later. 5. Using super thin cyanoacrylate glue reattached the top portion to the main slab clamping tightly with a c-clamp. Asusual all prep was done under a zoom scope at 10x to 20x magnification using a Comco abrasion unit and in this case a German Pferd MST 31 scribe exclusively.. Not a lot of scribing was done other than to outline the bug as the skin was not in great shape. Abrasion was pretty much done with a .18 and .10 nozzle using 40 micron previously used dolomite at 30 PSI. Here is the bug after about an our of prepping . I have outlined in red where you can still see the outline of the section that was glued down. A lot of people do not realize that many of the fantastic trilobites you see on the market have actually been glued back together because the splits are often through the bug. I once did a Moroccan trilobite that was in 7 pieces when I received it Here is the bug after another 40 minutes Took some pictures of the prep but frankly they ended up too blurry to use so here is the prep after abrasion is complete and after I have repaired a lot of the parts that broke of in the split. I tend to use a white repair material and always take a picture to let the owner know what has been repaired Here is the bug after coloration applied . The repairs were allowed to cure overnight before coloration and a bit of extra carving to clean up spots.Just waiting for me to do a final cleanup tomorrow after everything has cured a bit more. A long way from being the worlds most pristine or perfect bug but I am relatively pleased that we were able to breath some new life into an ailing bug. Totally prep time about 3 1/2 hours over 4 days. I suspect the owner will be pleased with the result. I have seen people toss bugs in the field that were in this type of shape. For those of you who just need to know the bug is 27mm x 18 mm A slightly different view

I have been working on making my own air abrasive unit but the pen section I created it not precise enough being made of plumbing parts. I am curious if any of you have found a somewhat affordable pen. I have only seen tip replacements and pens with the abrasive feeder. Thanks

I just found this paper on air abrasion for those of us that would like to increase our knowledge and maybe adjust our techniques while using air abrasives. EDIT: SEPARATE LINK TO SOURCE https://palaeo-electronica.org/content/2018/2279-air-abrasive-fossil-preparation

A few weeks ago I realized it had been a few years since I fired up my little prep lab. I went through a career change and I've been super busy. Decided it's now time to take a little time for myself. So I bought a few unprepped fossils on that auction site and today I finally got to work. I started on this little gal from the Weeks formation and, of course, my air compressor decides it didn't want to come out of retirement and crapped out on me. Now I have to wait until I can get a new one, just as the fever was striking again. Oh well. Here's some pics. I forgot to take a before pic, so I had to screen shot the auction listing. It's the one on the far right. The seller listed it as Modocia whiteleyi.

I could use some help in getting a new air abrasion setup. I ordered a MicronBlaster only to find out that they have closed. Their web page works nothing else does. I now have to jump thru hoops to get my money back. I tried the HF etcher and had no luck getting it to work. Looking for something of better quality without going broke.

So I recently purchased a blast cabinet to eliminate some of the dust from abrasion. But, I don't know if I connected the shop vac properly. I connected it to the side(where there was a filter already) with duct tape. It feels like it's drawing some pressure, but it just doesn't seem right. The cabinet stays clear for me to work on fossils, but a lot of medium remains in the cabinet. Any ideas? Suggestions? Pics of your own setups?

I'm just curious to see what all your pros are working with. My station is pretty much complete, I have a limited area in south tampa. I've seen a lot of the air abrasion boxes, and I'm curious, what's the point? Why not just use a full face APR, gloves, and call it a day? Anyway, SHOW ME WHAT YOU GOT!

I have been meaning to do this little experiment for some time. Normally an essentially complete trilobite from Penn Dixie in upstate New York will take me about 30 to 40 minutes to prep. Prepping one of these is relatively easy and generally gives decent results. The dark black trilo against the grey matrix always comes out nice.These trilos (eldredgeops) are about as common as I can collect and I probably have hundreds in buckets that might get prepped someday. So for the experiment I took a trilobite that was essentially complete and substantially covered with matrix. This was an extremely inflated specimen that just had a couple of defects in a few pleura. The experiment was to prep the trilo from starting to end using only the best techniques that I would generally reserve for a much better specimen than this one. The normal 30 - 40 minute prep would look something like this all done under a scope at about 7x magnification using a Comco MB1000 air abrasion unit Air scribe using an ARO till trilo is pretty much exposed Any remaining air scribing with a Pferd using fine stylus Initial air abrasion using a .040 nozzle and 80 micron dolomite Bulk air abrasion using .030 nozzle and 80 micron dolomite Final air abrasion and clean up using .018 nozzle and 40 micron dolomite The Experimental Prep All prep done under a scope at up to 40x magnification For this one air scribing was limited to using the Pferd with a fine stylus All air abrasion was done with .015 and .010 nozzles using sub 40 micron dolomite Max PSI used was 18 PSI and went as low as 3 PSI in the eye area under 40x magnification The difference It too 6 hours from start to finish and I think it looks fairly decent. Actually still needs a bit of cleaning with a fine toothbrush to get out a few bits of fine dolomite powder in the crevices... Note there is no restoration or repairs of any kind on this trilo. Has a nice pyritized burrow off to one side going under the trilo. Not the best photography here just with my cell phone... 2nd and 3rd pleura damaged on this side as well

Anybody used a Prep start Air abrasion unit for cleaning fossils, was looking to purchase one for my home workshop and was wondering if any of these dental units are useful for prepping fossils? Mainly the Prep start though as this is one i have an option to buy. If any one has a video of one in action that would be brilliant, or images of work they have done with one, that would be most useful. Cheers Dan