Back again. Managed to finally get my mill sorted out for the 60" bar again (I'd previously had the 42" rails on it) as I'd been asked to mill up a heap of Redgum logs for a winegrape client of mine. I'd also had another winegrape client hit me up for a decent Redgum slab to put above the fireplace in his new house. I had to rush it a bit as I am getting my right ACL done in my knee this Thursday so will be out for a bit.
I spent a couple of nights setting it all up after work and modifying it a bit. I'd previously had issues with it moving from the vibration during the middle of a slab no matter how tight you did it up. It still needs some extra bolts to lock it and stop it from moving up/down. The last slab had a 4mm difference from one end to the other due the the setup shifting despite doing it up with a max setting on the Hitachi 18v impact wrench. It's actually a GB double ender mill designed for dual powerheads but I'm only running my single 3120 on it. I couldn't afford to run two!
The bar is an odd one and is an older style (now discontinued) GB Ti Roller Nose in .058" - with these bars the actual base of the drivelink is meant to run on the roller and they seem to be designed for .404" only. I've run a number of these bars in 3/8" 25" and within seconds they start smoking the tip up as the tiestraps end up running on the nose rails instead of the drivelinks bottoming on the roller. The only fix is to either run .404" (not ideal for milling) or grind the rails back to suit the 3/8" chain at the nose.
I had a Carlton ripping chain already setup for the bar in non skip and decided to make a couple of extras in 188DL. Interestingly I threw the original chain later in the day on the LAST slab and damaged a few drive links. It was then that I found the original chain was bloody 190DL and I'd miscounted it and made 2 x 188DL instead. Regardless of what people may think even 1DL short on a 60" bar means the bastard WILL NOT FIT
This meant I had to make the original chain useable again which took probably 30 minutes in failing light.
I actually brought my cordless Hitachi 5" grinder with a 1mm cutoff disc as I thought I "may" have to turn the chain into a skip sequence but the 3120 pulled it fine and it was clearing chips well and leaving a very nice finish.
I got my dad to come and help. I'd forgotten just how hard this thing is to push through wood. All up we were milling for nearly 9 hours. I was going to stick this in the milling forum but a fair few people read this thread so I thought I'd stick it here instead! The widest cut we made was about 44" and the max cut of this mill with this setup is a measured 54.75".
Auxillary oiler setup fitted which I changed the position of soon after this photo to the other side of the nose on the chain's outfeed side. For those not familiar wth the 3120 it comes with an "oil boost" lever. When switched on this thing will pump out ample oil, even on a 60" bar - it positively slings it off the end like a 390XP will do to a 20" with it's oiler flat out. On a different bar an auxillary oiler "may not" be necessary (even though I'd still run one as long bars are not cheap!) but these roller nose bars have a habit of toasting themselves if they don't get enough oil and milling is tough on bars too, especially in dead Redgum.
Some piccys..
The largest log here with some beautiful wood in it. The standard aluminium rails I have are 3m long and I also have 2 x 1.5m extensions that can bolt on. They align perfectly. In this photo the rail length is 4.5m with one extension fitted.
I have some videos too and will upload them soon.
