Thanks Gary for the input - obviously you are a very accomplished machinist while I am a wannabe - self taught. The table torque I referred to seems to manifest itself when retrieving the table while
boring . No matter the depth of cut the bit in the boring bar will cut while backing the lead screw unless I use my hand and exert pressure on the table to prevent it or back off on the cut a few turns before retrieving which , given the low quality of the machine leads to other issues in re establishing the cut depth accurately. I believe ( in my admittedly amateur way) that the table itself is not flexing but it comes down to slop in the ways / gibs .
At any rate, thanks for your offer of help - I’ll soldier on as is for now as I am not making aerospace components but if it worsens I’ll reach out to you.
Thanks again- Richard
first of all not all boring bars are made the same. Best for your small work are the ones used in a jig bore head. Or for real small work try making them out of junk high speed drills. Almost all boring bars will cut a taper, and this is why you see folks cutting in and out. In otherwords you feed the boring bar in, and you feed it out. Often making more than one pass thru the hole. Wait till you get to try some tough stuff. I was pretty good on a lathe and a mill, but flat dangerous on an external grinder! Just never ran them enough to get used to them. Never ran a thread grinder, but worked on them a good bit. Jig bores and machine centers were my specialty. I built them for a living. I’m actually a machine builder by trade with a machine repair backup. It’s all bearings, shafts and gears to me.
Now when you get the chance; look under the table on the bottom side. There should be two clamp plates under there. They’ll often have shims in them. Just remove the shims to where you can get a .001" feeler gauge in there. If that dosn’t help; then you need to think of scraping. That machine wouldn’t be that hard. Wait till you have to do a seven axis machine center with all the compound error starting to stack up. I did jig mills (a high end machine center) that had a max error of .000020" in twelve feet. Sounds ugly, and it is the first time around the block. You soon learn to do it with proper equipment.
gary
Really great thread! Awesome build.