WFTF Target Checker

Description

2018

At the end of 2018, I started to print and assemble the WFTF Target Checker MK2 (Brian Samson’s public domain design, under the CC0 licence).

2019

It turned out soon enough that despite some well-engineered design ideas, there was still space for improvements to make the target checker safer to print and easier to use, also adding a few new features.
I made the following additions and improvements in the MK3 version:

• Depth gauge has a higher thumb screw to make it more comfortable and easier to adjust.
• Added stainless steel nut and bolt to the thumb screw, to make it more reliable.
• Added a countersunk eyelet and a wrist strap / lanyard.
• Greater tension for trigger shear spring that wasn’t strong enough, to make the target checker safer.
• Added a pyramid of 15/25/40mm blocks to quickly check target diameters.
• Improved fixing of the main spring at the back end.
• Made a mirrored version for the part above to fit to both left and right wind springs.
• Bolts and nuts are surrounded by the material to prevent warping and layer shifts while printing.
• A bit bigger grip but still comfortable with smaller hands, too.
• In general, rounded at many places to have a nicer look and allow high speed printing.
• Evenly distributed orange and black colours so that it is harder to lose and easier to find in the woods.

The internal parameters (spring size, travel, weights etc.) remained the very same so it is fully WFTF compatible. Actually, no serious changes have been made, this is rather a facelift with small improvements and corrections.

As the idea of Brian Samson’s target checker project is to give something back to the world of FT and HFT, I decided to add my part to it, too – so that shooters and clubs all around the world can benefit from it.

Together we can move forward FT and improve the design for the good of all. I will gladly share the STL files of the improved MK3 version with anyone who wants to print his own version.

2020

The new MK4 version added further features to the discontinued MK3 models:

• Further improvements to resolve all remaining issues of the original design.
• Re-designed stronger nests for the M3 bolts/nuts to prevent sinking-in.
• Trigger shear has been made much safer.
• Re-designed internal parts, while keeping the probe mass and momentum.
• Spring tension can be fine-tuned (within about ±25%) with a 7mm socket key.
• Small window with pointer to check the actual spring position.
• Free travel length of the probe has doubled, it’s more than 2″ (51mm) now.
• Black wrist lanyard for the orange body versions.

2023

The MK4.1 version with some small things have been improved:

• Fine tuned the trigger and the end of the piston to have a safer trigger action
• Improved piston space on a hexagonal base
• Wider space for the depth gauge to move freely
• One-piece front centre region with a perfect hole (instead of two halves)
• Aligning features for the two halves
• Bolts and nuts sit slightly below the surface and give a stronger connection
• + and – signs at the power setting scale
• Logo and version number engraved into the sides
• New colours: Dutch Orange, Ultra Marine Blue and Traffic Red, all with black sides.

2024

The newest MK4.2 version has another batch of improvements:

• Completely re-designed trigger, much stronger structure, wider button surface
• Re-designed spring guide unit
• Equivalent pellet energy 5.5ft/lbs (adjustable between 3.5–8.5ft/lbs)
• Bespoke 17.5ft/lbs version is available upon request
• New thumbscrew design (same as on my SmartPin etc.)
• Several smaller changes I did not bother to list here :-)
• New colours: Dutch Orange, Ultra Marine Blue, Traffic Red, Leaf Green, Intense Green, Fluorescent Pink and Signal Yellow, all with black sides (and black depth gauge, trigger and wrist lanyard).
• Other colours and bespoke colour combinations are available, too.