Holey Galahad FAQ

Frequently Asked Questions

Holey Galahad®
A Window To Your Work!

Question: What is the difference between a Galahad® and a Holey Galahad®?
Answer: Holey Galahad gives you new "See Through"
technology that allows you to see the wood through the disc. Holey Galahad is available in three tungsten carbide grit
surfaces; coarse, medium and fine. Galahad discs are full bodied discs available in five grits. Holey Galahad has been shown to increase productivity by 10-15%.

Question: Are there any size differences?
Answer: Both Galahad and Holey Galahad are 4” (100mm) in diameter. Galahad is available in both 5/8” (16mm) and 7/8” (22mm) center holes. Holey Galahad has only 7/8” (22mm) centers but will fit angle grinders worldwide using our improved Universal Nut.

Question: What is the comparison between grits?
Answer: All discs feature patented structured tungsten
carbide teeth bonded to steel discs over the total cutting
surface. For original Galahad customers, here is a tungsten carbide grit comparison which applies to both round and flat profiles:
Holey Galahad Coarse (Blue) = Galahad Extreme Coarse (Blue) 90 grit
Holey Galahad Medium (Red) = Galahad Coarse (Teal) 70 grit
Holey Galahad Fine (Green) = Galahad Medium (Silver) SSG390

Question: What Angle Grinders fit Holey Galahads?
Answer: They’re designed to fit most 4-1/2” (115mm) and European 125mm angle grinders. Maximum 14,000 RPM.
All Holey Galahad discs are 4” (100mm) in diameter with 7/8” (22mm) center hole size to suit angle grinders worldwide by being seated on the manufacturer’s 7/8” (22mm) arbor. This is a spacer located at the bottom of the center shaft and the 7/8” (22mm) arbor is a raised round shoulder as an integral part of the spacer/washer.

Question: Are they made in the USA?
Answer: Very proudly, yes! This is US technology, patented worldwide and made in the USA.

Question: How many different shapes or profiles are
available for the Galahad and Holey Galahads?
Answer: Two, rounded and flat. The rounded profile is extremely suitable for round, concave and contoured surfaces like the inside of bowls or scalloping out chair seats. The flat profile is most useful in smoothing out notches on logs,
removing large amounts of bark or smoothing out large,
predominantly flat surfaces like doors, beams and mantle pieces. Either the flat or round profiles will do any job above. The above applications are recommendations based on
experience and are a guide for you to determine the best
profile for your application.

Question: How many grits are available for the
Holey Galahads?
Answer: Three.
1) Coarse 90 grit (Blue)
2) Medium 70 grit (Red)
3) Fine SSG390 (Green)

Question: How do you grade the grits and their finishes between Galahad and the Holey Galahad discs, starting
from coarse to fine? What are the part numbers and what’s
the difference between them?
Answer: Galahad Discs
1) Model #11019 Ultra Coarse 120 grit Black. Shapes fast and furious but leaves lots of dust and
a real coarse finish. This will git ‘r done!
2) Model #11017 Extremely Coarse 90 grit Blue. Rapid removal with less dust. Leaves a coarse finish.
3) Model #11018 Coarse 70 grit Teal. Rapid removal leaning toward medium finish.
4) Model #11004 Medium Silver. Denser grits. Doesn’t need much to final finish.
5) Model #11003 Fine Silver. Very small dense grits spaced minutely together
for fast removal and a close to final finish.

Holey Galahad Discs
1) Model #47851 RCB Round Coarse Blue 90 Grit. Rapid removal with smooth, course finish. Great for
rounded, concave and contoured shapes.
2) Model #47852 RMR Round Medium Red 70 Grit. Rapid removal with medium to fine finish. Great for
rounded, concave and contoured shapes.
3) Model #47853 RFG Round Fine Green. Doesn’t need much to finish sanding. Great for
rounded, concave and contoured shapes.
4) Model #47871 FCB Flat Coarse Blue. Rapid removal
with smooth, coarse finish. Great for long, flat surfaces.
5) Model #47872 FMR Flat. Medium Red
Rapid removal leaving medium to fine finish. Great for
long, flat surfaces.
6 Model #47873 FFG Flat Fine Green. Doesn’t need
much to final finish. Great for long, flat surfaces.
Note: The coarser the grit, the more aggressive and less cleaning is required. Each model leaves a different finish.

Question: Should I remove the safety guard?
Answer: No! No! and Heck No! We do not recommend working without a safety guard for any reason. It’s not good for your health or safety. Any foreign objects in the wood or material you’re working on will be deflected away by the guard versus coming toward you. Should you hit an immovable object and you lose control of the angle grinder, you’re much safer with the guard on.

Question: What happens if I hit a nail, wire or foreign object in the wood? Or what if I drop the Holey Galahad or Galahad disc on the ground?
Answer: You will more than likely lose some carbide grits or cones where you made contact with the obstruction or dropped it. This isn’t a big deal and you can easily continue working – unless you lose so many it affects your finish and production – then you need a replacement.

Question: Why are they so expensive?
Answer: Because the grits consist of tungsten carbide
needles and manufacturing is an intense 5 stage patented process. These high quality discs have proven longevity and can be used over and over again, saving hundreds of dollars in sandpaper, time, labor and effort.

Question: What is the best angle to position the safety guard?
Answer: Holey Galahad discs are designed to cut with
the safety guard set between 23 degrees to 45 degrees.
The angle of adjustment for the safety guard varies with
each disc grinder manufacturer.

THE MAIN CRITERIA IS THAT THE BOTTOM OF THE
SAFETY GUARD MUST BE AS LEVEL AS POSSIBLE WITH THE BOTTOM OF THE BODY OF THE DISC GRINDER. In this position, the SAFETY GUARD WILL ADJUST BETWEEN THE (APPROXIMATE) ANGLES OF 23º and 45 º.

Main reasons for this requirement:
1. Safe and efficient operation: Holey Galahad discs were designed to shape and carve with the bottom and partially exposed left side peripheral edge as well as on their face. With the safety guard rotated to the correct position as stated in these instructions, it opens up the bottom surface of these discs near the bottom of the grinder. This is where a considerable amount of the main shaping and carving is done and is:
A) a vital part of its versatility
B) allows for optimum carving utilization in a
comfortable and safe position.

2. Direction of waste: With the safety guard properly adjusted, direction of wood shavings and sawdust will be angularly deflected over the top of Holey Galahad, hitting the top of the work piece and away from the operator’s hands and face.
If the guard is retained at 90 degrees, the full left face,
including the nose (or front tip) of the Holey Galahad will
be exposed. In this position Holey Galahad will not carve smoothly or effectively and poses a potential hazard to the user by jerking to either side. You don’t want to ruin your work piece nor run the risk of a violent motion with the grinder being jerked sideways. We absolutely do not recommend moving or retaining the safety guard at 90º or even close to this vertical position.

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