Fossil Prep Lab
Fossil Prep Lab
Nearly all fossils when found will require additional preparing to bring out the best each specimen has to offer. This goes far beyond hand picks, pin vices and vibrating engravers. While there are many methods and tools used for fossil prep, we’ll keep things simple and outline the basics of what we have. Our intended purpose for this section is to offer some basic hardware and application advice based on our own experience. For additional info post a question in the forum for a timely response.
This prep lab has constantly evolved over the years into its current compact set up, allowing for the actual collections area to expand into much needed space previously occupied by prep lab. The lab is set in a narrow area where every station is little more than a few feet away. Multiple stations are needed to accommodate different stages of prep and being able to literally roll the chair to the next station makes things a bit more efficient. Nearly every stage of the prep process is covered in the lab including pre-prep photography. The only exception is that of final photography which is covered in the Photo Lab section under resources.
Above: Fossil prep lab
The main tools we utilize are air scribes, micro-sandblasting units and dust collection/exhausting units. Since the soft tissues on our trilobites are very delicate we lean heavily on micro-sandblasting as our main prep method. We current utilize three different micro-sandblasters, three different air scribes, and two types of dust management systems; each one is used for a slightly different application and is described below:
SS White/ Model H (Micro Sandblaster): http://www.airbrasive.com/modelh.asp
This is a large, industrial type abrasive unit. The machine is built for high volume, continuous blasting. We use it for removing thicker overburden layers when air scribes are not an option due to their vibration. This unit has been reliable and works well for its intended purpose. We would caution perspective buyers to be certain it fits their needs as the price is (was) around $6,000 several years ago.
Crystal Mark/ MV-241 (Micro-Sandblaster): http://www.crystalmarkinc.com/?page_id=195&category=14&product_id=7007
This is by far our favorite and most versatile machine. The MV-241 is a compact unit offering the ability to switch between high volume and delicate work with its two outlet nozzles while utilizing one media canister. This is done simply by pressing a toggle switch. One hose outlet is made for aggressive work, while the other is for finer more detailed work. This unit is extremely reliable, predictable and very versatile. It has trick features such as a hinged media canister that can simply be tilted and vibrated for easy media changes, cleaning etc. But for all the MV-241’s cool features we love it because it’s extremely precise. The cost is reasonable at $3,275.00. Although this unit is manufactured by Crystal Mark, Inc., paleo application sales go through Paleo Tools. We love Paleo Tools and we highly recommend for them and all of their products (www.paleotools.com).
Our favorite and most versatile setup in the lab. The Crystal Mark MV-241(right) and the TURBO-Station combined work box/dust collector.
SS White/Model K: http://www.airbrasive.com/modelk.asp
This is our oldest machine by far, both in the number of years we’ve owned it, and the manufactured date. In fact we really don’t know how old this unit is, possibly the 1960’s! This was a used machine upon purchase. This unit was the solo workhorse for many years and handled the job brilliantly. It has never broken down other than normal wear and tear issues and seems to handle about anything we can throw at it. The machine was modified a few times to do extremely delicate work and seems to transition between heavy and light work easily. The unit is at home whether at 1 psi with little powder flow, or blasting at 120 psi with maximum cutting power. Over the years SS White has made some changes to the Model K, mostly all for the better with the exception of replacing the electric foot pedal with a less responsive pneumatic version. The price range is $2,500-$3,000 (we were unable to find exact pricing).
We have purchased all of our air scribes from Paleo Tools. They are currently the only easily accessible supplier of air scribes that are specifically modified for fossil preparation use. We have had good luck with all of their units and have found the company to be very friendly, accommodating and helpful.
Paleo Tools/ME-9100: http://www.paleotools.com/me-9100.html
This air scribe is our favorite for medium to heavy work. It has the power to do fairly heavy matrix removal, yet with the right bushing up front is also capable of fairly fine work. You can take a medium size block apart pretty quickly with this unit, yet it doesn’t seem to suffer from the stalling problems that many air scribes have. If there could be only one….this would be the one, at least for us.
Paleo Tools/Paleo-Aro: http://www.paleotools.com/paleo-aro.html
This unit is good for light to medium work. The Aro is a bit finicky and likes to stall quite a bit in use. It doesn’t like much pushing pressure so it’s best to let it do the work. The unit is capable of some pretty fine microscope work and excels at finding the sweet spot for flaking small pieces off the fossil without damage due to its relatively high frequency vibrations.
Paleo Tools/Micro Jack: http://www.paleotools.com/micro-jack.html
This unit is good for extremely fine work. We have the Micro Jack #4 and wouldn’t part with it for the world. At 40,000 CPM and up depending on which one of the six variants you have, these things are amazingly precise. This unit is easy to control and one can get very close to the fossil under the micro scope with little effort and minimum risk of damaging the fossil. The stylus on this unit is literally a tungsten carbide ‘needle’ and takes significant abuse with ease. Your fingers will also take significant abuse if you’re not paying attention and the tungsten carbide needle jabs into one.
There are two ways of dealing deadly accumulating dust caused by using micro-sandblasters; capture it in a collector or exhaust to the outside. We do both. This has been an area of constant frustration over the years as there are few reasonable and capable options for doing this below an industrial grade collection system, and industrial is a problem for residential structures for a variety reasons (noise, power supply, etc.) This is a serious issue because most of the blast media we use is 40 microns or less, with some media as small as 50 nanometers. That’s 1/50,000 of a micron! A standard 1 micron HEPA filter won’t do the job. Breathing this dust will bring your life to end pretty quickly regardless of what type of media is being used. One of the main things to consider when buying a collection/exhausting unit is noise level and scfm (suction).
Crystal Mark/Work Chamber TURBO-Station: http://www.crystalmarkinc.com/?page_id=195&category=6&product_id=5700
This is an ingenious unit where the work chamber and dust collector are incorporated into one unit. The work chamber is fairly large, high quality construction and able to handle good size pieces with the dust collector built into the rear of the unit. The link above lists the suction power at just 258 scfm which is a bit misleading. Many dust collectors are 400 scfm+ but the difference here is the dust collector is built in, meaning there is no hose to and from the collector to the work box which causes inconsistent suction in the work chamber. The dust collector motor in this unit is extremely quiet, so quiet in fact you can take phone calls while working. Definitely the quietest dust collector we’ve ever owned (and we’ve owned a lot of them). The price reasonable is at $2,895.00.
Above: Crystal Mark TURBO-Station. Combined work box and dust collection system.
Vortex 6 Inch In-Line Fan: http://www.horticulturesource.com/vortex-powerfans-vortex-inline-fan-6-449-cfm-1-to-11-each-p1580/
This is an inline fan unit, meaning it simply sits in-line within duct work. It simply sucks the dust out of the work chamber and exhausts it directly outside through ductwork, PVC, etc. This unit is extremely powerful at 448 CFM and relatively quiet. These units can be had for around $150 on Amazon new for the 6 inch model and more for the larger ones. Some maintenance is required in terms of cleaning the fan unit occasionally but otherwise this is a good option for working with smaller micron (sub 25 micron) media. Keep in mind if you live in a residential area exhausting directly outside means taking other precautions to protect your neighbors from the dust (and yourself if the wind blows the dust back into your house). Consider venting directly underground, under water in a bucket or in some other type of collection receptacle.
You’ll notice around the lab pix there’s a lot of other hardware. We touched on the bigger stuff but the little things are also just as important. For lighting sources we prefer fiber optic light units with flexible goose necks. These offer clean, cool directed light at your specimens. We have a host of different stereo microscopes as well. Each station needs one. They are available from a variety of different sources both used and new. The big thing to worry about with stereo scopes is make sure it has boom if it’s the extension-arm type, and make sure the unit has sufficient working distance from the subject, usually 8-10 inches is suitable.
Anytime you’re working with compressed air, it’s important to have a clean, dry source for your tools. Since these tools require large volumes of air over time it’s important to get an air compressor up to the task. In recent years a host of ‘oil-less’ air compressors have become popular due to their supposed ease of maintenance. We have NOT had good luck with any of these units and seen most of them break, explode or otherwise die within a few months of operation. We don’t recommend them. A good oiled compressor with a holding tank of 25 gallons or more is suitable. These are tried and true, quiet, and fast. If properly maintained they last virtually forever.
Air scribes and micro-sandblasters each have different air requirements. The air scribes need clean, dry air, but also they require automatic or manual oiling every hour of use. An automatic oiling system can be placed in line after the micro-sandblasters to oil the scribes as needed, or you can do them manually. By contrast the micro-sandblasters require clean, extremely dry air.