[Jay C]

I recently won a used CNCFusion kit from EBay. I thought I would share some photos of the installation process as I proceed. Maybe this will help others miss some of the mistakes I made

First thing I did was read other installation notes (Woodenspoke's especially) about their mistakes so as not to repeat them. I succeeded in that goal, but I found new ways to screw up. I also had a printout of the instructions ont he CNCFusion site, and finally, a printout from www.fignoogle.com about how to take the x and y axis screws apart.

Onward. First step was to remove the table from the saddle. This was easy to do. All you need to do is remove the left end table plate (2 6mm SHCS), loosen the x gibb screws (leave the screws in place), and crank the table to the right until the screw disengages. Then remove the brass nut held in place with two allen head screws (leave the screws in place). The first photo (table_remove.jpg) shows this step.

Next, to remove the Y-axis screw from the base. Just remove (and save the two 6mm SHCS) and spin the lead screw out of the brass nut. Then loosen the SHCS holding the nut in place. Now is a great time to clean the grease off and lube the ways. The second photo shows this step (yaxis_remove.jpg).

Now I switched over tot he CNCFusion directions. I laid the mill on it's back and inserted the ball screw and nut assembly into the slot that held the brass nut, and through the hole in the base. See yaxis_ball.jpg To get the new bearing block/servo mount installed I first tried using the short end of an allen wrench. A better way was to remove one screw from the stepper plate and swing it out of the way (yaxis_plate.jpg). Ok, here comes mistake 1. The instruction state "Pull the saddle forward, so the ballscrew is now sticking out the hole in the base far enough to slide the Y-axis motor mount onto the end of the ballscrew. Re-assemble the Y-axis motor mount to the ballscrew. Be sure to get the collar tight against the bearings." Well for some reason I took this to mean attach the bearing block then push the collar while tightening it's set screw. But it didn't pay much attention to the position of the ball screw with respect to the base. What I mean is that the screw was butted up against the rear of the case ... I could never get it tight. So I took it back apart and “played” with it. It finally dawned on me what I needed to do (at least I think it’s the right way). With the y-axis beating/stepper mount unscrewed, I grabbed the saddle and pulled it as far forward as possible. I used the x-axis brass nut as a spacer to press against the locking collar. To exert the pressure, I used a Quick-Grip against the back of the saddle and the x-axis brass nut (yaxis_collar.jpg).

The X-axis was a PITA. According to figNoggle’s directions the thrust bearings just slide off the leadscrew. Well, on min the rear thrust washer (I’m guessing the name sorry) was stuck solid on my axis. I could get it partially of (maybe .5” of the 2.5” distance) and it would wedge tight. I hate to admit it but I didn’t want to stop, I had already been at it for a few hours, so I went medieval with a baby sledge and a pair of locking pliers to act as an arbor. I already know it was stupid so save the lectures  Maybe others can learn from my haste and waste. The piece finally came free and looked fine so I proceeded. I used 2 Quick-Grip clamps (xaxis_collar.jpg) to apply the pressure for preloading the thrust bearings. The rest of the X was cake.

Which leads me to the Z-axis. Per the instructions I saved the worst for last I’ll type more when I can.

Jay

[Jay C]

This weekend I got to finish my CNC driver/power supply (Hobby CNC Pro 3-axis with a 32V 10A linear power supply). I finished wiring my steppers and making my connectors as well. I installed the steppers, added the wire loom, and gave it a test. I mounted a 0-1" DTI on the table resting against the head. It's a cheapie I used on my microlathe. Using the MDI (after configuring my steppers of course) I gave x-axis a backlash test. Well, I'm ashamed to admit .058" backlash. I have not tested any of the other axis numbers. I have a feeling my Fred Flinstone act on the old x-axis leadscrew and thrust washer may be part of it, the other is not being able to access the set screw for the x-axis ball nut mount on one side. I have not tried to work on this yet so this post is strictly preliminary assumption. To add however, I can hear a "clunk" when the table reverses, so the gibbs probably need to be adjusted too.

FWIW,
Jay

[Jay C]

Update: yesterday I bought a new (set of ball ended allen wrenches to help me reach the x-axis ball nut set screws. I started the process by manually turning the x-screw and noticing a "springy" feel to it. I decided it might be that my gib was too tight and loosened all 4 set screws until I could back drive the axis. That made it easier to turn and removed the springiness, then then I noticed severe backlash. As I pushed and pulled the table, I peered underneath and saw the source. The thrust bearings were moving in and out of their housing with at least a quarter of an inch movement. This means my technique for installing the locking collar was flawed (anyone keeping track of my errors).

I loosened the locking collar screw, and pushed the x-axis as hard as I could. Sure enough, the slack appeared on the right-hand end of the screw. For those of you keeping score this was the same type issue I had on the Y-axis when I installed it the first time and the same fix. Oh well, I take it as a learning experience that will aid me with future projects. I re-tightened the collar (using the same method I used on the y, but I don't think it actually matters to tell the truth) and remeasured my backlash this AM. .005" I can work with that. I turned on backlash compensation in Mach3 and ran a simple back and forth test with said backlash. On the money.

More to follow
Jay

[Jay C]

Ok, yesterday I stole some time to sneak into the garage and check the Y and X axis. As for the Y I had the gib set a bit too tight on this axis too. I measured the backlash at .0025 (using a cheap DTI so take that with a grain of salt ... I do ). I plugged this in and got 0 backlash so I moved on to the Z.

I already know I need to take the Z apart and tighten the gib screws ... it's actually part of the CNCFusion directions. But I decided to measure the backlash anyway. .0025" too. So as a test, plugged it into Mach3 and remeasured it at 0.

My method for measuring may not be correct and I plan to do more testing but here is what I've used thus far:
On the X, using my mag base I use a 1" travel dial indicator. Using MDI I moved the table in the - direction until the indicator read 0 (just to make the math easier). Then I reset the DRO in Mach to 0 and used MDI to command g1x0.070 (maybe I should have used 0.1). I'd return to 0, and repeated this at least twice. Whatever the discrepancy was I plugged into Mach 3's backlash field. For the Y I used my DTI (which says .0005"). This also means I was restricted to smaller movements. I use the dial indicator on Z too.

My next tests will involve commanding the axis to travel further from the start point. All in all I'm happy with the current results. I'll chuck up a pen and draw some circles.

Anyone have any comments on my methodologies or suggestions? Oh, and I also need to tram this thing. Not sure how I'll do that yet with the parts I own ... need to do some research to see what I can fashion that will work with my DTI and the dovetails it has.

Jay

[Jay C]

Well 400+ views and no input which means I'm doing everything right

In any event I was determined to test this thing tonight. First I tried the RoadRunner (it's tradition right?) but it was set for mm and I didn't know the quick and dirty to convert it, so I tried some of the other G-files that Mach3 includes. No good. So I went to the wizards and used the circular pocket wizard. I'm still getting used to my "envelop" and how I should set up my soft limits, and of course what the 15+ input fields on this particular wizard all do. But, despite the learning curve, I was able to mill two circular pockets in some scrap MDF.

The first one was 1.5" in diameter and I left is set for a .75" endmill but used a .125" one. Left a nice spiral wall in the pocket. Then I milled a 3" diameter circle hoping for the same wall effect but it came out cleaner Ah well ... I'm jazzed about this small accomplishment. Now I need to understand more about how to visualize my table and protect it better with soft limits.

Maybe this post will generate some feedback

Jay

[Ninhil]

I will be up and running to where you're at in a couple weeks time.

Its good to read about your experience, and I too, will await an experienced member's reply.

[melodesign]

Hello everybody there, as I am bigining in english I have some difficulties to express myself what I precisely want meaning. But I would like to say that I am a novice in cnc technology I am still studying a lot to learn the secrets behind of it. Actually I have been learning a lot with the tips found in the forum, and I started to design my first CNC Router that I intend to use it for woodarts.
And soon I will post some pictures of it for everybody to apreciate it.
Thanks a lot,
Sincerely
Melodesign

[Jay C]

Ok, I'm a bit late with the Z-axis report. And as such, I might gloss over some important points while not having any "in-progress" pictures. Apologies but maybe something I write will help others.

I started my Z by removing the fine feed, the rack and pinion, the torsion arm assembly, and the stop at the top of the column. Based on another user's comment I decided to flip the stop block so the lever would be on the right side. Two words of warning as Murphy paid me a visit:
1. remove the z-gib before raising the head up and off the column as the gibb will fall into the column
2. Cut the wire tie that holds the two conduits to on another before you are holding 40# of cast iron and motor in you hands to avoid ripping anything out (I was able to reseat the head on the column while I did this).

Note:The riveted scale on the right hand side will be in the way of the stop block and will need to be removed.

Note/Tip: Put the head back on (if you choose to flip the block like I did) and set your gib now. One you install the kit, you can't reach the set screws as the ball screw covers them. Otherwise, after you install the kit, you have to remove it and reinstall it (per the instructions). This is more difficult if, like me, you decide to use screws and nuts rather than tapping the column (didn't have a 6mm tap ) Holding the nuts is a royal PITA and so I recommend you don't use nuts and buy a 6mm tap.

You don't/won't need the torsion arm once you add the stepper, but before then, the head will back drive the screw so have your stop block set up. The Z travel is huge now, wish the Y was 2 inches bigger.

FWIW,
Jay

[turbostang]

Jay - Excellent project. One I am getting ready to embark on myself. I have a couple of n00b questions. I had not heard of the CNCFusion till I saw it mentioned in your post (Yeah, I'm that new). Check, it looks like it's a lot easier to buy their kit as opposed to making it.

My main question is in regards to limit switches / hard stops. I always see them mentioned, but never see where the come from, if they're part of a kit etc. Where do they come from, is it part of another kit or ??

I've already downloaded the MACH software, and looked at the same files you spoke of.. the circular pocket etc.

How is the accuracy / repeatability of this little booger?

Thanks Jay! Sorry for the book!
-Brooks

[Jay C]

Jay - Excellent project. One I am getting ready to embark on myself. I have a couple of n00b questions. I had not heard of the CNCFusion till I saw it mentioned in your post (Yeah, I'm that new). Check, it looks like it's a lot easier to buy their kit as opposed to making it.

Depends on your skill level, but for me it was way easier to buy than build I am going to make my own belt drive conversion though.

My main question is in regards to limit switches / hard stops. I always see them mentioned, but never see where the come from, if they're part of a kit etc. Where do they come from, is it part of another kit or ??

There are industrial limit switches that are hermetically sealed, have adjustable stops, debouncing, and other bells and whistles. I used simple surplus micro switches wired per the Mach documentation. I only have the y-axis at this point but I have wiring ready if I decide to do it for X and Z too.

I've already downloaded the MACH software, and looked at the same files you spoke of.. the circular pocket etc.

How is the accuracy / repeatability of this little booger?

Thanks Jay! Sorry for the book!
-Brooks

Ah, now that I have not tested yet. Heck I still need to tram it. I have been distracted with home improvement projects to play some more.

Jay

[turbostang]

Thanks!

I am probalby going to get the kit, making it would be no problem - but I have other projects to get rolling on

Which controller board are you using? I've seen a bunch of them on ebay, but they never seem to have any names on them?

like this one:

http://cgi.ebay.com/3-AXIS-CNC-ROUTE...ayphotohosting

[Jay C]

Hobbycnc.com the HobbyCNC Pro

Is the X2 big enough for you ... if I had the space, I would go X3 in retrospect Of course everyone says that. A new option is in the works too: www.cncbridges.com

[turbostang]

yeah, I started wanting the HF mill - Now, I've improvised my plans and I think I'm gonna step it up to the Sieg X3. And now, thanks to you, I'll probably be upgrading the table at some point in time, Lol.

I'll probably run it quite often, so a more sturdy mill is in order.