Rong Fu Clone (HF33686) head movement question

[Tomzo]

Greetings - as I am learning more about this machine I am noticing that irrespective of how tight I tighten the bolts that fix the head, it can still be moved by hand with less effort than I think it should, and has also moved when an end mill dug into some aluminum when I took a bit more of a cut than I should have. I am wondering if this is normal or a sign of some defect that I need to address. I am not at the point where I want to do a big stabilization system at this point as a VFD is next up for this machine, but if that is what it takes I guess I will need to add that to the list.

Thanks

 

[mikey]

Definitely not normal. You have a clamping issue.

 

[Tomzo]

Good to know - I think I will address it when I am pulling the motor off for the VFD - the head will be a lot lighter if nothing else!

Thanks

 

[mikey]

Yeah, have a good look. The head on my RF-31 is rock solid when the head locking bolts are tight.

 

[markba633csi]

Check the fit of the head to the column. It may be easier if you took some weight off like removing the motor so you can wiggle things

 

[Tomzo]

For sure - I already have a 2 HP three phase motor that I got off Craigslist but I need to install a new 220V subpanel in my shop as I don't have any 220V circuits available. I have it all planned out - now it is just a matter of making the time to get that done. Part of me wants to install one of the variety of methods to maintain position when raising and lowering the head but that makes this project even more complicated. I tell my self, "one thing at a time Tom...."

 

[C-Bag]

First thing I’d look at is the two pinch bolts. Somebody might have put too long of bolts and they are bottoming on the shoulders, or left off the washers.

 

[mickri]

In the interim before you make one of those head alignment thingies you could try out my method to bring the head back to position after moving the head. I have a DI on a rod on a magnetic base. Place the rod and DI against the head. Zero the DI. Do whatever you need to do. Then bring the head back so that the DI reads zero as the head just touches the rod.

 

[Tomzo]

So I decided to check some of the suggested things this morning and went to remove the nuts from the clamping posts. It seems that somehow in its life somebody knackered the threads on the post - those nuts will not come off. I tried a cordless impact driver to no avail. I could have broken out the breaker bar and forced things but decided against it. I did work them back and forth (about 1.5 turns total available movement) and was able to get a better clamping action that way.

I think that when I move the mill to do the VFD upgrade I will take another run at this - and have some replacement clamping bolts at the ready should things go sideways during the process....

 

[yendor]

I'm curious about the Clamping bolts for your head to the Round Column Post?
On my RF there are (2) Bolts with Nuts that sit in captive recesses on the opposite side.
I don't need to hold the nuts when I loosen the bolts to swivel or raise the head.