FLK Tech 8 SET 5/8" Plug Wedges and Feather Shims Concrete Rock Stone Splitter Hand Tools 16mm

I wish I knew about these sooner. I’ve used them a bunch since purchasing. Still holding up.

We had a 4’ x 2’ boulder in front of our cottage that protruded 6” - 8” above the surface and was a trip hazard. I purchased 5 set of 5/8” diameter carbide SSS drill bits and the set of feathers and wedges. I was successful getting rid of the top of this granite boulder.Firstly you need a DSS hammer drill and multiple bits, I used all 5 on this project.Patience is needed and I recommend thorough research. The Trow & Holden Co. Was the best resource plus YouTube videos.Bottom line is 4” spacing of holes in a straight line starting on outside edge, not the centre. Drill 2”-3” deeper than wedge length. Don’t push hard on the hammer drill, clean out hole as you go, cool bit frequently in water and/or rotate bits. Push the feathers down into the hole about 75% of their length to give more wedging space. Pay attention to lining up wedges so they are all splitting in same direction of break line.Play the piano with your hammer. Go up and back tapping each wedge a few times.as the wedges go deeper one may get refusal but try the others if possible. The sound of hammer hitting the wedges will change. After the wedges are not going down any further, leave them to keep rock under strain to hopefully start cracking.You may need to remove wedges at some point, tap them side by side and pull feathers out with vise grips. I found they worked better keeping them soaked in some oil to reduce friction.This is not a 2 hour job, I probably spent 10 hours on this tough rock just to get top 6” off. Various chisels, prybar, sledge hammer, kneeling pad, etc. are needed. Good luck, be patient, it can be discouraging but they do work. I was planning on using Declan and bought a 1-1/4” carbide bit but not needed and am returning it.

Used them to fracture a large block of concrete. Used a 5/8" drill bit for foot deep holes. Tried a 1/2" drill and they do fit snugly, but I don't recommend that because it caused me to bend one of the feathers. The big O Ring that holds the wedge and feathers together is nice, but keep spare o rings because they get beat up and are a consumable. The wedges do mushroom and chip from the hammer, so wear safety glasses. Mushrooming happens.

Great value for the money and they work just fine. Just take precautions regarding the large amount of dust the drilling of the holes will create - a normal issue with using a hammer drill on stone or concrete. I was able to trim back some ground level stones of a rock wall that were a hazard to my lawn mower without disrupting any parts of the rock wall. Attempts with hammer and chisel did not work well, but these wedges and feathers worked perfectly, and those stones were really tough.

Took care of some half buried boulders. Rubber o-rings don't last too long but I wasn't expecting much from those.Solid steel can take a beating. Was very impressed with the size of the boulders I was able to break up.