Below are tips on getting the most out of your Grex pinner. Consult your owner's manual for a comprehensive guide on tool operation and maintenance.

General Operation

Make sure the nose of the tool is held firmly onto the work piece.

Do not let the tool bounce back when a pin is driven. Because these fasteners are so fine, even the smallest gap left between the tool nose and work surface will prevent the tool from setting the pin all the way.

Always drive fasteners in opposing angles (toe-nailing).

This goes for any nail, but even more important for headless pins. Instead of purely relying on the friction from the fastener shank to provide the holding power, the physical orientation of the pins, when driven in different angles, will help lock the work pieces together even better.

Pull your work pieces together before fastening them.

Headless pins won't be able to draw your work pieces together, but they will hold securely as long as you first pull the work pieces together before fastening.

Position the tool perpendicular to the wood grain.

The chiseled end of the pins will tend to cut the grain instead of following it off to the side. This helps increase the pins chances of be driven straight.

Loading Fasteners

Only use fasteners designated as 23 Gauge HEADLESS pins.

Do not use 23 gauge pins that have a brad or slight headed brad, doing so may cause jamming and damage to your tool.

Do not use 1-1/4" (32mm) length pins.

Doing so may result in jamming because the magazine is not designed to accommodate this pin length.

Load fasteners carefully.

When loading fasteners, insert a strip of fasteners down into the magazine rail. Then slide the fasteners forward all the way into the tool nose before closing the magazine cover.

Always load pins with arrows pointing down.

Towards the direction that pins will be driven. This guarantees that the chiseled end is entering the work piece. Otherwise, jamming can occur which will lead to driver damage.

Only load a single pin length at any given time.

Never load different lengths and/or types of fasteners at the same time. Doing so, could result in jamming and/or damage to your tool.

Before loading, remove existing pins and/or pin strip fragments.

Before loading fasteners, ALWAYS remove existing fasteners and/or fastener strip fragments in the nose area that may have been left over from the previous work session. Loading fasteners of different lengths may cause jamming and/or damage to the driver.

Load to the right of the Auto Lock-out lever.

If there is an Auto Lock-out feature make sure to load fasteners to the right of the lock-out lever and then slide forward all the way into the nose area before closing the magazine cover.

Mark your fastener strips with a black marker.

Partially used strips may not have an arrow prined on them, making it difficult to know which end is pointed. You may wish to mark each fastener strip before loading to indicate which direction to load. Use a black marker and draw a line across the bottom of the fastener strip. When you're left with partially used fastener strips, you'll still know which way is down even if the arrows aren't there.

Use Grex 23 gauge headless pins.

Although any brand of 23 GAUGE HEADLESS PINS are compatible with your Grex pinner, Grex pins are highly recommended due to the optimal tensile strength of the steel used. Using poor quality pins will cause jamming and damage to your tool.

Operating Pressures

Test drive fasteners into work piece.

Before driving fasteners into the work piece, test drive fasteners on similar materials to be used in the actual application to determine the optimal air pressure.

Operate your tool at 100psi.

Generally speaking, when working with traditional hardwoods such red oak and maple, maintain an operating air pressure of 100psi. For pin lengths longer than 1-3/8", maintain the operating air pressure at 110psi. For harder woods, your Grex pinner can be operated at a higher air pressure.

Insufficient operating air pressures will damage your tool.

Insufficient operating air pressures will prevent your tool from setting pins all the way into your work piece and also cause the driver to drive pins in at insufficient speeds. This forces the driver to “push” rather than quickly “punch” pins into the work piece resulting in excessive stress on the driver tip, which will lead to increased wear and damage.

Excessive operating air pressures will damage your tool.

Excessive operating air pressures may set pins too deep into your work piece, damage the work piece, over stress the tool and increase driver wear.

Match the operating pressure to the work being done..

If driving short pins (less than 1-3/8") into softer woods (pine, cedar) then 70 to 80 psi is sufficient.

For longer pins into softwoods, 80 to 90 psi

For longer pins into softwoods, 80 to 100 psi

For short pins into hardwoods, 80 to 100 psi

For long pins into hardwood 110 psi

For short pins into exotic hardwoods, 100 to 120 psi

For long pins into exotics 120 to 140 psi


Do not drag tool across work piece while fastening.

Be careful not to drag the nose of the tool on the work piece while fastening. The driver tip is extremely fine. If the nose of the tool is accidentally dragged across the surface before the driver returns into the tool body, then the driver could get caught and be damaged.

Do not pull trigger if you suspect a jammed pin.

If no pins are driven when the trigger is pulled, STOP. Do not pull on the trigger again. Check to make sure there are no jammed pins in the nose area. Always clear jam when it occurs before using tool again. Otherwise you may cause damage to the tool.

Keep you tool lubricated.

Put one to two drops of tool oil into the air inlet for about every 2,000 pins driven. If an in-line oiler is used, lubrication through the air inlet is not required. Don't over lubricate your tool.

Driver life expectancy is dependent on operating condidtions.

The driver life expectancy is highly dependent on the operating air pressures, pin lengths, pin quality and hardness of wood. Consult with the owner's manual to operate the tool at the optimal air pressure. Driving longer pins and/or into harder woods will naturally wear out your driver quicker.