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Already have a Chicago Pneumatic CP9361 or a ZOIC Chicago? Want to convert it into a ZOIC Chicago (Extended Reach)? Our mod kit converts the CP 9361 air scribe into a ZOIC Chicago (Extended Reach), opening up a range of possibilities in your prep and allowing you to work on those really fiddly specimens where there never seems to be enough space to work.

Simply screw on the body containing our fossil preparation modifications and start prepping! Your tool will become the ZOIC Chicago (Extended Reach), with all its features and benefits. It will accept the range of interchangeable styli that we offer (choice of 1 supplied with mod kit):

The CP 9361s became the staple of the fossil prep laboratory in the 1980s and 1990s, with many of these still going strong today (a testament to the durability of their internals). You’ll read a lot about it in books, articles and magazines from that time. However, over the years more appropriate and specialised tooling for fossil prep has become available, as the CP 9361 air scribe was originally designed as an engraver.

Please be aware that this is a front end (body and stylus only) modification kit - it is not a pneumatic tool in its own right. It requires the base model of the Chicago Pneumatic CP-9361 to function. You can also use this mod kit with your ZOIC Chicago. 

Our Modifications

Variants of the CP-9361 have long been used on hard matrices due to their impact-driven internal mechanism, and are found in just about every professional prep lab in the world. The impact-driven internal mechanisms (piston/cylinder combination - more details here) give the tool power, whilst the size allows for detailed work. Chicago Pneumatic boast the highest durability on the market for the internals of this particular model. We’ve stripped the CP-9361 of any features that are not suited or durable in fossil preparation, and replaced them with our tried and tested ZOIC PalaeoTech features.

Our modifications are optimal for fossil preparation, and will withstand the test of time. Our stylus bushing is designed for minimal noise levels, whilst allowing a frontal exhaust that clears what you’re working from of dust as you go. The stylus bushing is hardened and tempered so that you never experience any stylus ‘wobble’, even if you use a lot of side-to-side motions when working.

We have also given the tool a rubber coating to minimise vibrations, provide more grip and provide some kind of insulation against the cold air flowing through (a nice touch considering so much fossil preparation takes place in unheated garden sheds!).

Technical Specifications

The air consumption (amount of air the tool requires to run) is about as low as it gets for a fossil preparation tool at only 6lpm (0.2cfm), providing 13,500 bpm. The ZOIC Chicago has a nominal and maximum operating pressure of 6 Bars (90 PSI). A low air consumption means that your compressor will kick in less often creating less noise and costing you less to run. Low air consumption is also a great indicator of quality in air tools – the engineering in this tool is exceptional.

What’s in the Mod Kit?

You will receive the body, our hardened bushing and either a pointed or a chisel stylus of your choice. You will also be provided with a user manual, air tool oil, o-ring grease to make sure that you can keep it in top condition.

Our Mod Kit will fit the following:

  • CP-9361 manufactured in Hungary (the latest models)
  • CP-9351 manufactured in UK
  • CP-9361 manufactured in USA
  • The ZOIC Chicago

This will fit any other front-end modification of the CP-9361.

It is better value if you are purchasing all new to buy the ZOIC Chicago (Extended Reach) straight out, but if you already have a CP-9361 or have picked one up second-hand this will likely be the most cost-effective approach for you.

Check that your CP-9361 is the real deal first

The CP-9361 is so ubiquitous that it has inspired a number of cheaply made and mass-produced copycats over the years. Some of these are sold as engravers, and some are misleadingly marketed as fossil preparation tools. Please note that we cannot guarantee this mod kit will fit or be suitable for non-genuine versions of the CP-9361.

Genuine CP-9361s will come with their paperwork if bought new, with a serial number engraved onto the body which corresponds with that in the paperwork. It will also have been made in Hungary if bought recently, and the UK or USA if purchased previously.

If you are not sure if yours is genuine and you didn’t purchase it from new there are a few things you can look out for. Some knock-offs utilise the outside of the CP-9361 making it appear genuine, when the internal components (the crucial bit) are counterfeit.

The copies suffer from a variety of problems, due to low-quality manufacturing. Impact-driven tools are the most difficult to produce to a high standard that will withstand the test of time, and so are best avoided if they are low quality. These knock-off versions are unlikely to last more than a few weeks/months without experiencing problems. If you’re unsure what you’ve got, a few things to look out for in knock-off varieties are high air consumption (low engineering tolerances put the air consumption through the roof – the CP-9361 air consumption is a very frugal 6l per minute), and problems with consistency in the way the piston moves in the cylinder, such as jamming or getting stuck and intermittent sluggishness.

Please be aware that this is a front end (body and stylus only) modication kit - it is not a pneumatic tool in its own right. It requires the base model of the Chicago Pneumatic CP-9361 to work as a fossil preparation tool.

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