[AndyCBR]

Hello,

I've owned this machine since new in 1997 and it has always had this problem. I have used it enough recently that I want to find a solution.

When the fine feed on the mill spindle is engaged the handle is drawn into the belt housing and creates some interference. This persists until you reach the end of travel and reverse the fine feed and start going back up.

I've played with the inch dial and servo gear positions to no avail.

It seems some type of bushing has moved in the system or perhaps was not set up right since day one.

Any light that you could shed to help the blind man find his way would be appreciated.

Thanks,
Andy

[smallblock]

Andy,
On those early machines with the drill press function the shaft passes through the " shifter " block horizontally. On each side of the block is a bushing which sets the amount of end play. The bushing is held in place by a set screw on the top of the block. The force of using the fine feed handle when milling can cause the bushings to wear out the dimple where the set screw engages and then you get a lot of horizontal movement in the shaft and backlash. You can loosen the set screws, and turn the bushings to find a fresh area for the set screw, adjust them for minimum lash and then re-drill the dimple to a deeper depth for the set screw. JT used to sell a thrust bearing upgrade for them also for the guys with CNC .

[AndyCBR]

Thanks for the help. I did dome more investigation and it looks like one of the bushings was pushed out about 5/8" and that was why the handle was getting "drawn in" to the machine as you lowered the quill.

Good news is seating that bushing flush and tightening that set screw helped but there is still a "bad spot" in the drive mechanism that binds up the works and attempts to push that bushing out when you stroke through it. Some lube and working back and forth has helped but the mechanism still gets jammed up repeatably about every 28 revolutions of the fine feed handle when the quill is disengaged.

SO, something is binding in there and I think that is what is causing the bushing to move.

I put a call in to JT to see if he can point me in the right direction.

[smallblock]

Check the rack on the back of the quill and also the rack gear that drives it- you may have a chip stuck between the teeth.

[AndyCBR]

Check the rack on the back of the quill and also the rack gear that drives it- you may have a chip stuck between the teeth.

I will look into that.

I would like to ask JT for some ideas before I tear into it too far. Is there a good way to handle taking apart the spring loaded assembly that retracts the quill?

This machine has under 1 hour of use (spent a lot of years in storage) so I am pretty sure whatever is going on is from original. I am kind of reinventing the wheel years later with this old machine as I never went through the tweaking process way back when I bought it. I regret not getting it sorted out back then.

[smallblock]

(spent a lot of years in storage)

Substitute " rust" for "chip"

[AndyCBR]

Substitute " rust" for "chip"

Could be, odd that the rust would only appear every 28 revs of the handle but stranger things have happened I guess.

It was in the crate for 5 years or so indoors. In a garage (not carport) sitting idle much of the time after that.

Spoke with JT today and he gave me some tips to take the assembly apart but did say that something could be going on in there as it is weird it only seems to bind in a certain spot. I'll have to take it apart and see what's up.

Smallblock, are you affiliated with Shoptask/Shopmaster?

[smallblock]

I've owned 3 of their machines over the years- now waiting for the arrival of my new Mill Turn.

[precisionhone]

you need the weld it and keep the fine tune always on and drill and pin the bushing to the right to keep it from coming out. This machine is another fine POS of JT's ripping people off. He will tell you to try this try that. But will never admit its just a pile of scrap. BTW don't make a warranty claim he doesn't respond well to them or ultimatums. My brand new 2014 patriot has .006 clearance in the bore to the quill. causing it to walk .010 to .015 when trying to center drill. 3 months of back and forth still nothing. Now he voided my warranty because I sent a replacement part back that was cracked a couple days after his 30 day return fee.

[smallblock]

Precisionhone-
You already have your own gripe forum- why jump in here and muddy up the waters when people are trying to help the guy.
BTW- if you fail to return the parts, you void your own warranty.

[precisionhone]

I returned the parts. After 2 weeks of no reply from JT I sent the cracked part back. I was going to send everything the whole bridge and the quill but he doesn't want to fix it. I paid for a new machine and expect it to be new. Not have to fix it before I can run it.

[precisionhone]

Weld the inside bushing to the shaft. Then pin the bushing to the right. Make sure to tap the handle of the fine feed in towards the head stock to seat everything before you drill and pin it.

[precisionhone]

Good luck with your new untested mill turn. Why do you think it was a total redesign? I will never buy from JT again.

[smallblock]

AndyCBR,
Whatever you do- don't listen to precision hone- whatever he cobbled up in his picture will render your whole mechanism useless.

[smallblock]

Good luck with your new untested mill turn. Why do you think it was a total redesign? I will never buy from JT again.

Thanks, It will be my 4th unit from Shoptask and everyone has paid for itself many times over. Why a complete re-design? Why are we not all still driving Model T's- the answer is obvious.
BTW, from your picture, I can see why you can't drill a straight hole.
As far as not buying from JT again, I'm sure he is elated to hear it.

[precisionhone]

It's so new there's still paint inside the bore. Maybe there's so much clearance to the quill is why it won't drill a straight hole. Attachment 275306Attachment 275308

[precisionhone]

Yes you won't be able to use the quick mode anymore. the fine feed is locked on and works just fine. It's just another ****ty JT design that we have to fix. JT is still redesigning because he still hasn't found something that works yet. Well I shouldn't say that. it works but if you want it to be acurrate you need to fix this try that drill here add more supports weld this and then scrap it and buy something else.

[sharpshooter90]

Wow- If I did a weld like that, I sure wouldn't post it for the world to see. What machine are you working on? That looks like one of the old 90's units, not a Patriot.

[AndyCBR]

I'll try and stay out of the debate on Shoptask and only speak from my experience.

I'm just trying to get mine running right. I paid $1495 in 1997 so I never expected a Haas or Mazak for that money. I did expect a machine that would fully function in all three axes and so far I am not quite there yet but I'll get it figured out.

JT has been helpful thus far in working through some of these issues with my machine. I have tried to politely request help rather than demand anything. You get what you give.

With the little use I have had with my machine the mismatched screw dials (some inch and some metric) are especially vexing. It's one of the main reasons I am looking at a DRO system (see other thread). I need a compound tool post too (wasn't standard back in 97). So, looking at a $1k investment in a $1495 18 year old machine. I think anyone in that situation would question that logic.

It's the main reason I want to use it more so I can justify buying some tooling. The more tooling, the more you can do.

I love the concept of the machine. The few times I have used it to mill a bracket for clearance or chamfer a wheel spacer, face or polish a part, etc. it has been great to have. The mill is probably the weakest point of the system but is certainly better than no mill at all. The machine is capable of much more than I am so I have a ways to go on my machinist skills.


Back to the point at hand. JT said he could source a bearing that may help in this condition and I'll probably take him up on that. I still think the root cause of the bushings moving is the internal stiction in the gear assembly. You can spin the handle with one finger until the 28th revolution. I need to take it apart to see what is going on in there.

What is the best way to handle the quill spring on the rear? I'm quite sure I can get it out but getting it back in may be tricky depending on how much preload there is. Any tricks to getting that assembly apart?

[AndyCBR]

Looks like my last post got deleted with all of the moderation. I don't have the time or inclination to retype it all. Whether the Shoptask is a good value or not is obviously beyond the scope of this thread.

JT offered to source a bearing to help in this area and I may take him up on that. I still think the root cause of the bushings moving is the stiction every 28 revs on the gear assembly (even without the quill engaged). When you hit that stiction it acts like a bearing press to push the bushing out.

Any tips on getting that assembly apart? I know there is a screw under the dial.

What is the best way to handle removing the spring loaded quill?