Recently someone interested in fossil preparation asked what are best air-scribes for the money or in other words: are more expensive air-scribes worth the extra money and what's the difference?
In short, since prep is not just about fossil-preparation techniques, but also about knowing how prep-tools work, and cleaning and maintenance of prep-lab (which sometimes takes too much time): most cheap airscribes are s**t - not recommended for professional (frequent) use, poorly constructed and built with inexpensive non-durable materials! You get what you pay for... They work, but not reliable, at the very least expect problems sooner or later... On the other hand, depends, can be a cheap alternative for hobby...
For each airscribe or a micro-sandblaster, like for any other tool, there are hundreds of copies with different brand-names. While all sandblasters are built on the same principle and use the Venturi effect to pull the abrasive sand into the stream, the differences between different types of pneumatic engravers (air-scribes) are more noticable, resulting in different frequencies and amplitudes of the stylus, noise level, vibrations... Most are not specifically designed or modified for fossil preparation, but more expensive air-scribes are usually better constructed, more durable, more precise, run smoother, require less pressure to run, have lower noise level or require no or minimal maintenance. If an air-scribe is good or not (for fossil-preparation) does not depend on the price or brand-name, but on the construction, materials used and type of prep (rough, fine, detailed) and how it feels in hand. Not all air-scribes are fit for all prep-jobs or fossils... One can ask all the questions you want, there is nothing better than experience after you get to test the tools, but perhaps this 3 minute writing helps someone, if asking the same questions...
The difference between a cheap and more expensive air-scribe in one example: If you are prepping fossils long enough, you have for sure heard about Chicago pneumatic airscribes (CP 9361 in example) - the most popular prep-tools back in the 1990's and probably the most copied air-scribes since, and thus nowadays still some of the most frequently used air-scribes in preparation (under a different brand-name)! So what's the difference between the more expensive 250-600$ original USA made CP (nowadays also known as the modified versions: ME-9100 and W880) and a cheap 50-70$ Chinese copy of CP?
Except for the more durable steel parts:
- original CP runs smoother and is a more versatile tool
- adjustment dial (which permits you to select the appropriate power level) powers the scribe OFF/ON below #1 at original CP, while the Chinese copy is not so well constructed and the scribe powers OFF/ON at around #2.
- at max adjustment dial above #5 the original USA made CP is about 2x more powerfull as the Chinese versions
- 2 days after using a new Chinese copy the adjustment dial started leaking air, o-ring needed replacing (no air-leak problems with decades old USA made CP)
- expect more problems with stylus not moving (air flowing through) in the Chinese copy
- USA made CP is not without flaws, it's an incredibly loud scribe and transfers a lot of vibrations, needs regular maintenance, but the Chinese copy needs more frequent maintenance, cleaning...
- both can get some jobs done, but expect the Chinese copy to malfunction. The roll pin, piston and cylinder are common cause of these scribes malfunctioning, cheaper production and materials used can break or wear faster...
All in all, considering most brand-name air-scribes are copies aswell; 50-70$ is still a good value for the price/performance, when used properly...
