Paasche

[Bob Saunders]

Hi, we stopped at a thrift store and bought a as new Paasche H # and H S# airbrush. It has the side reservoir and two sizes of glass jars and air hose. $3.50. I can use it for my art work. Any one know if this will work with baking soda as a micro abrader for fossil prep?  Bicarbonate of soda if there is a difference.  Before I try it. Will be more likely to do 2-3 inch fossil hash plates with Crinoids to start. 

Thanks, Bob

[Ptychodus04]

I do not believe this will work for abrasives as it is designed to pick up liquid paints.

[Bob Saunders]

Thanks, I watched a video today showing the Paasche with the covered metal vial on top. I now realize that I would have to remove the needle and maybe enlarge the tip  hole. I do not have the item number for the one in the video if still being made. Another man filed a hole in a piece of hobby brass tubing and stuck it thru a pill bottle. He was also using powered dolostone. easy for me to make one.  

[minnbuckeye]

11 hours ago, Bob Saunders said:

easy for me to make one. 

 

 I have a Paasche that I haven't used in 15 years. If you figure out how to convert it, as you said EASILY, I would love for you to document how and post !!!!

 

Mike

[Bob Saunders]

for Mike and others. Here is the video of the home made blaster. I can do that, but not a lean against air nozzle.  He also didn't mention lbs of air pressure or size of tube so it doesn't plug up.  . I have a regulator for my model engines. 

 

 

[Ptychodus04]

This setup is pushing so much abrasive that it looks like it will decimate most fossils. You would need high psi to get the velocity of the abrasive up with such a large orifice. 
 

For my Green River preps, there’s so little abrasive (sodium bicarbonate) flowing that most of the time you can’t even see it coming out of the nozzle.

 

IMHO, DIYing a micro abrasive setup for any kind of detailed fossil prep is a recipe for disaster.

[Bob Saunders]

Thanks, esp. when I heard using "play sand!" as a media. Maybe if you could mask off the fossil and then abrade away a significant  unwanted surrounding matrix. and the Dremmel with diamond bits and hobby grade  air or electric engraving tools? Their is likely classes you can take but as a retired senior unlikely to travel for such.

[Ptychodus04]

For fossils, one wants to scribe away bulk matrix and abrade fine matrix. Abrasion that doesn’t cause damage is done slowly and carefully at very low pressures (typically), with relatively soft abrasives (3.0-3.5), under modest (10-20x) magnification.

 

If a prep goes fast, you are likely to have significant damage to the specimen. If an aspiring preparator can’t afford super-expensive purpose-built tools, that’s ok. They simply have to understand the level of prep that they can achieve with the tools at their disposal. I’ve spent 2 decades working up to the tools that I currently employ for prep work and only in the last couple of years have I been able to acquire some high quality gear.