Rong Fu Clone (HF33686) head movement question

Tomzo said:
Wait - a gib in the column? I am not seeing where one would be on the round column.
Click to expand...
Sorry, thought it was a square column Rong Fu clone - which DOES have a head gib.
 
Tomzo said:
Well I can't turn them more than one full turn when loosening. Must be really galled up. When my replacement bolts arrive I will get them off one way or another as they won't be going back on. I will also check the gap to make sure it is clear. Thanks


Sent from my iPhone using Tapatalk
Click to expand...

Have you tried placing a block of wood on the table and lowering the head until the spindle rests on the block, unweighting the head's clamp to the column, and then working on removing the pinch bolts? It's possible you have some deformation from past use that is catching the bolt threads. Tapping the threaded end with a brass drift while unscrewing the bolt with a wrench may help. You may have a little clean-up to do afterwards so the new bolts slip in freely.
 
pontiac428 said:
Have you tried placing a block of wood on the table and lowering the head until the spindle rests on the block, unweighting the head's clamp to the column, and then working on removing the pinch bolts? It's possible you have some deformation from past use that is catching the bolt threads. Tapping the threaded end with a brass drift while unscrewing the bolt with a wrench may help. You may have a little clean-up to do afterwards so the new bolts slip in freely.
Click to expand...
Good idea - I will give that a go.
 
The bolts on the RF clone do not rotate. Only the nuts are free to rotate. The head of the bolt is captured in a hexagonal pocket, preventing rotation.

It seems suspicously coincidental that all three nuts would lock up. I would suspect that some external influence was used. Possibly, the P.O. used LocTite on the threads for some unknown reason. Extreme rusting would also cause this symptom.

If you are able to turn the nut slightly, I would put a suitable lubricant on the nut threads and work the nut back and forth. With each attempt to unthread the nut, try to force it a little more. I have used this technique on impossibly frozen nuts with success. If there is no success with this technique, heating the nut could help, especially if LocTite was used.

If still no success, grinding the nuts away with an angle grinder and driving the bolts out with a punch will certainly work. If all else fails, cuting the bolts in half via the rear opening in the slot in the casting will allow you to pull the half with the nut out with a pair of Vise Grips and drive the remaining half out with a punch.
 
There is a member gravydog that has done several great mods to his RF. One was an alignment guide to keep register on the head as it was moved up and down and another was making cam locks to replace the lock nuts. I thought both were really worthy ideas as the cam locks would be quicker and easier than the nuts and a socket wrench. All of his posted projects are ideas I’m going to incorporate when I quit having to deal with the more pressing projects I have stacked up.
 
So I put a dab of thread lubricant on the exposed threads and went back and forth will a little battery powered impact driver (light duty one). I managed to get the bottom one off and oh boy, are those threads toast. The upper one does not want to budge so this seems like a good excuse to buy a more powerful impact wrench! I have the replacements coming in the next day or two so I think I will be retiring these bolts.IMG_0538.jpgIMG_0539.jpg
 
pontiac428 said:
Here you go, man!

I don't have time to teach everyone how to fish, so here is a free fish!
Click to expand...
Special thanks to @pontiac428 for the tip to the McMaster Carr parts list - those worked GREAT! That spherical nut/washer system is perfect and tightens up really nicely. One of mine was so galled up I had to drill it out - started small and once I got up to 1/2" the nut came right off. It was actually easier than I thought it would be - for once!

Quick question - since using a wrench in there seems to always conflict with my quill lever arms, is the use of a torque wrench to gently tighten/untighten these a bad idea? It seems easier to me to just "store" my torque wrench there by the mill so I can quickly loosen and tighten those nuts.
 
I just made a socket and a stubby breaker bar permanent fixtures, same as the draw bar wrench. Torque is something you'll get a feel for as you use it. It takes "enough" torque. I snugged my head bolts down firmly. I lubed up the threads and flanges with a quality anti-seize so they torque smoothly and don't gall. Makes life easier when you need to move the head.
 
You must log in or register to reply here.
Back
Top