I work on a daily basis with 3D Printers to develop new ideas and technologies within the fields of FDM. Anyone who works with 3D Printed parts knows that getting the internal diameters of holes correct is almost impossible and I still have to resort to using a Hole Reamer to get the bore sized correctly. Following this up with the added complication of requiring threads, it can all go horribly wrong very quickly.

Making prototypes in the workshop often means needing to print or machine parts with correctly sized holes for threading. At first it was simple enough for me to do by hand. However as the number of holey parts increased, along with the need for square threads, I had to borrow a friends converted drill press to do the work effectively.

Eventually I had to return the converted drill press, but my friend was kind enough to have made a smaller version as a replacement for me to keep. As news spread around the workshop of this wonder tool, which works with both metals & plastics, it became harder to get my hands on it for my own use. The solution was to source another drill press and have it converted too.

However, that is not as easy as it seems. The good drill presses are hard to find and expensive. On top of that I struggled to find a commercially available tapping jig which was accurate enough and at a resonable price. Whith an ever increasing number of holes and work being limited by the lack of suitable tools, it wasn't very long before I had a wholly brilliant idea....

The Tapping Tool was a project I originaly launched on Kickstarter, however it didn't reach it's funding goal. Rather than leave it forgotten and the time and energy I spent developing The Tapping Tool wasted, I decided to post this Instrutable :)

Step 1: Design Ideas.

The design is inspired by, and takes from, converted pillar drills. Other ideas come from google search, and a video i saw by JohnnyQ90 back in 2018 where he makes his own tapping fixture.

Additionally, considerations must be made for manufacturing, the use of off-the-shelf-parts, such as drill chucks, and easy of assembly.

Step 2: Designing the Tapping Tool.

I've used Fusion 360 to design The Tapping Tool. Each part is modelled individually and a final assembly containing all parts and fixings can be used to check fitment.

However, CAD can't be 100% certain and considerations must be made from non-tangible elements. These elements can be access to holes for the fixings and clearances for parts not in the models.

When machining parts the fewer the number of different operations or toolchanges the lower the cost of the part. Designing the part(s) to have all milling operations from one direction keeps the cost down, but also limits the design freedom. This dance between design and manufactuing is know as Design For Manufacturing, or DFM for short.

Design features I wanted to incorporate into The Tapping Tool.

Stiff & Ridgid Design.
Large Work-Space.
Simple to assemble. Quick & Easy to use.
Affordable.
Adjustable Depth-Stop.
Bench Mountable.
Slotted Base for attaching fixtures.

The original design process took several weeks of CAD. Once the first design is reached it is always good practice to make atleast one prototype.

Step 3: 1st Prototype.

As with any new ideas it is always good to have a test run and to check the design. I opted to 3D print what I could and adjust the CAD as required.

It is very easy to fall foul of 'CAD Eyes' where parts look waaaaay bigger than they actualy are. Having something tangible can be a great help when it comes to designing.

At this stage I didn't have the shaft or a chuck. I wanted to see how my design matched up to the reference pillar drill.

I'm using the E3D ToolChanger to print the parts.

Step 4: 2nd Prototype | Metal.

I don't have the facilities to made The Tapping Tool at home from the desired material, Aluminium. I have to go to machinists to have the parts made for me.

When the parts arrive it is always very exciting to see your hard work realised in solid metal!

I am still waiting for the chucks and shaft to arrive, they come from different suppliers in different shipments.

Step 5: 2nd Prototype | Chucks & Shafts.

The chucks, shafts and collars arrive shortly after.

Step 6: Weight.

Weight is very important to consider when you are looking to sell a product you have designed.

In the UK there is a huge jump in shipping cost for packages over 2kg.

The Tapping Tool CAD was updated to reduce the overall weight by ~200g to allow for packaging and to make sure the shipping weight would not go over 2kg.

Step 7: 3rd Prototype | ASMBL.

I have an E3D ToolChanger fitted with an ASMBL Subtractive Tool.

ASMBL is a technology I co-developed to integrate Subtractive G-Code (Milling) with Additive G-Code (3D Printing). E3D posted a blog about ASMBL, read the blog here | https://e3d-online.com/blogs/news/asmbl

The Tapping Tool Base, Upright & Arm have been manufactured using ASMBL. The parts will be very accurately made, the top surfaces with be smooth and flat, and the corners and edges will be square. This is not something possible with 3D Printing alone.

The parts are being printed in Prusament Clear PETG & ColorFabb XT-CF20.

The two videos below show ASMBL in action.

Loud Sound Warning!