January 17, 2014

40939 6x26 MINI knee MILL REVIEW

hf 40939 6x26 MINI knee MILL REVIEW,MINDLESS BORING: After some set-up and spindle time on my new harbor freight milling machine, I am glad to report of my satisfaction with the machine. While the hf40939 mill is not at the same level of build quality of Bridgeport in any way, It is however a reasonably priced milling machine, that I did not have to fix or rebuild before use. The 40939 mill was delivered to my garage door with a shipping weight of approx 684lbs, near a hundred pounds of which is crate and pallet. The machine does not come with a stand/base, so I made my own. In this video, the milling machine has been levelled. and the head has been tram square to the mill table. I have tried to take some measurement that may be helpful to anyone looking to buy a harbor freight 40939 knee mill, including spindle run-out and confirmation of the x,y axis 1" 8tpi lead screws and the .125 movement per rotate of the xy table handles.

Several modifications to the 40939 mill can be done to increase machine travels in all axis, ariser block to increase the z axis travel, removal of material from the x axis bearing holders and pocket can be extended to to increase the y axis travel toward the operator. Below are some measurements taken of the x axis in effort to find an "off the shelf" list of parts to add a power feed to the machine, and whether grizzly g3102 parts are a direct bolt on.
x lead screw comparison for power feed by grizzly little or no mods ----------measurments------------- I will begin,, hf 40939 6x26 x axis parts list all measurements taken with a tape measure x feed screw length -- 35.375" table end caps --- 2.00" bearing is flush to outboard ( left and right SAME) graduated collar ---- 1.600" hand wheel over all thickness --- 1.320" of this .390 extends into hand wheel for friction dial locking ( left and right SAME) x axis lead screw protrusion from end cap -- 2.306" x axis lead screw protrusion from end cap is in two steps, step 1 is bearing inside race diameter approx - .785 extending - .325 beyond c-clip step 2 is remaining lead screw shaft - diameter - .627" length from step 1 - 1.982" here we need someone with a g3102 to compare measurements to see if the 102 has same lead screw as 103 and if these parts can "bolt on" to a 40939 = SHARE ROCKNTV1