Hello Hello I have a new to me Takeuchi tb53fr. Recently broke the main pin that goes through the dipper n bucket. Broke in the middle down the center grease hole. I got some 4140p stock for the replacement pin and someone that can drill/tap it for the 2 end zerks for the thumb pivot points. Where I'm at, noone has a long enough drill bit to drill to the center grease hole. Solid pin sounds like the way to go from past threads and drill the dipper sleeve for a grease point. My problem is..... I am afraid to drill the dipper for the grease point. Is this safe to do? Where to drill? How hard is the steel on the dipper/sleeve? What kind of drill bits or taps would be necessary to do this successfully? Thanks for any insight or help!! D
Been there done that. Others may disagree, but I have drilled several sticks to install a zerk after installing a thumb. Location depends on the machine and what would be the easiest access for greasing. Weld a piece of angle so the "V" protects it or a piece of heavy pipe around. As long as you drill near the center you won't hit anything hard, normal shop drill bits, HSS or whatever should do the job easily.
Yair . . . Drilled pins obviously work on some applications but, over the past fifty years or so, I have seen so many break under innocuous conditions I sometimes wonder why manufacturers bother if it is possible to drill and zerk the boss . . . doubles the amount of grease points I know. Cheers.
Should be fine, just use cutting fluid when drilling it, being careful not to snap the end of the drill off half way in your hole, that would be annoying. I will be doing the same thing to my boom at the pin connection as i am not willing to pay $330 for a komatsu pin that is drilled. Normal (High speed steel) drill bits and taps will work good, just don't us a cheap brand. I use the Sutton brand, not sure if that's common in the US.
Ok, thanks for the response and info guys. All I have is HSS so if I take my time sounds like it should be ok. Pin milling is done and I'm gonna reinstall tomorrow. The cheapest I was quoted for a 45mm x 440mm replacement pin was $586 without shipping! The stock I bought wasnt cheap and milling was high demand pricing... but now I got a good quality pin for $185 Thanks
So I hit a snag. Drilled around 3/4" into the center of dipper boss for zerk and hit something seriously hard.. Likely super hardened sleeve matetial. The other pin holes dont have a full sleeve but looks like this main one might. Hmm, am I screwed? Should I drill through this super hard sleeve metal and add the zerk? Do I have to plug the hole and drill the long pin for a central grease hole? Insight appreciated, thanks.
Try a masonry bit if you have or can get one, you only need like an 1/8" hole for grease......
And sharpen the carbide to a sharper angle than you'd use for masonry, and resharpen as needed.
The parts pages on that machine show two bushings inside the dipper, prolly pushed in from each side until they touch each other, most likely that's the hardened steel you've encountered.
Masonry drill will work but the carbide grade is not well suited to drilling hardened steel. Look for an Artu drill bit. That will sort it
An alternative, which could be a bugger as well depending on what kind of tools you have to work with, is to drive the bushing out of the dipper and grind a notch hole in them with a grinder, then press the bushings back in. Of course you'd have to make sure the notch in the bushings lines up with the hole you've drilled.
Blow a hole through it with a torch or carbon arc?
Not a bad idea but with a modification. Grind or machine a groove around the id of the bearing and drill two or three holes through the groove. If the beating ever turns it will still take grease. Lantraxo,as for attacking it with a torch or arc air. Wash your mouth out with soap and water
Battlefield expedients RayF, lol :tong
Damn, Maybe take a photo of where your drilling, My excavator has 2 bushings in the arm and empty space in the middle where i would drill, and should be normal steel there, maybe not yours though, i would have a good look and make sure its not one bushing knocked out of place into the center. The idea about grinding the notch in the bushing sounds ok, but i would find out first, If it has a bushing right through i would first try drilling with a good sharp HHS drill bit with tapping paste on it pushing it hard going medium/slow and just see if it gets anywhere first.
I just tried drilling an old komatsu bushing out of curiosity in my workshop just then, they are super hard, prob not trying to drill. So the grinding the notch sounds like the next best idea, if it is in fact a one piece bushing.
I have seen excavators that had a spacer tube between the bushings rather than a stepped bore, but the spacer was not heat treated on the ones I worked on.