PDA

View Full Version : More Sherline mill fun & games.



DICKEYBIRD
10-10-2010, 03:54 PM
I’ve spent way more time than I want to admit during my “stay-cation” this past week massaging various areas of the little Sherline/Denford CNC Micromill. I’d hoped to have it all back together by now and humming smoothly but alas, it ain’t to be. I got tired of putzing around with finicky little crap and decided to stop for a bit and post a couple pics.

Sherlines’s website has a drawing of their latest x/y base that has several oil passages drilled in it with plugs at the ends that allows the leadscrews/nuts to run immersed in an oil bath. I duplicated their design and then turned up an oil reservoir out of acetal. It has an o-ring sealed cap with a vent hole. The vent is plugged up with a capscrew when not in use to prevent all the oil running out. You can see the extra nut that is adjustable to remove backlash but sure is pain to get set right. Hopefully the oil system will slow down leadscrew/nut wear.


http://i57.photobucket.com/albums/g227/DBAviation/Oiler.jpg

The Z-axis was a pain as well because it had about almost a quarter turn of backlash. Sherline’s website shows how they utilize their brass Z locking nut to adjust out the backlash so I plagiarized that idea too. I did add an acetal block between the two with a nipple in it to feed oil to the leadscrew. I’ll have to mount a small remote oil reservoir with the same plugged vent cap system as used in the x/y base and add a bit of flexible tubing. I cobbled up my own adjustable lock system and knob as well.

The blue disc at the top of the leadscrew is the extra roller bearing I added to replace the metal to metal plain washer system that Denford used. I turned off a bit of the leadscrew to make room for it. It is much smoother now!

The plate at the top of the column is a spacer I made to replace the metal I had to mill off to square up the end. It had 2 corners radiused off from the factory that allowed the stepper motor mount to dig in and cock when the mount screws were tightened. The mount was so crooked, the stepper motor shaft wasn’t even close to being aligned with the coupler. The coupler fell into 2 pieces when I took it apart. Mis-alignment metal fatigue killed it I’m sure. It’s now nice and tight & square so hopefully it’ll survive now.

http://i57.photobucket.com/albums/g227/DBAviation/ZOiler-Backash2.jpg

Next up is the z-axis counterweight system made from a couple of inline skate wheels for pulleys and bit of steel cable to take some load off the little bitty stepper motor.

Sheesh, I think I could’ve fixed up a “real” mill with all the time spent!

DICKEYBIRD
10-10-2010, 04:46 PM
Oh yeah, the other thing that arrived was the ER16/MT1 chuck that arrived from CTC last week. Looks great, fits good, haven't checked runout yet but it'll be good like like all the other stuff I've got from them.

I cut down a 3/4-16 nut and threaded it on before tightening the drawbar to help pop the taper loose when it becomes necessary to remove the chuck.

http://i57.photobucket.com/albums/g227/DBAviation/ER16Chuck.jpg

squirrel
10-10-2010, 06:49 PM
Are you milling warm butter with that monster in the chuck?

RB211
10-10-2010, 08:45 PM
Are you milling warm butter with that monster in the chuck?
LOL!

Anyhow, Dickeybird, the work you have done to your sherline looks really nice. Keep up the good work!

DICKEYBIRD
10-10-2010, 10:15 PM
Are you milling warm butter with that monster in the chuck?Hmmph! My Sherline ploughs through blocks of Asagio cheese without a whimper.:D

wierdscience
10-10-2010, 10:24 PM
Hmmph! My Sherline ploughs through blocks of Asagio cheese without a whimper.:D

Haha...too funny...Italian night features a Sherline to "grate" the Parmesan cheese:D


Nice work,don't feel bad about the time,I don't know how much time I have in my X2.

DICKEYBIRD
10-17-2010, 08:07 PM
Update: My plan was to finish the hardware mods this weekend and post a video of it doing something reasonably purposeful. Alas, I have it pretty close to finished and all the motors are running correctly but just plain ran out of gumption. I still have some software setup to do since a G01 X1 Y1 causes a movement of less than 3/4". I decided to stop for the day, post a couple pics, eat some supper and get ready for work tomorrow. I'm tired and would screw up something for sure. I guess it'll have to wait a while before making some CNC chips.:(

I added 2 braces to the top of the column to tie it to the enclosure and add some rigidity. The brackets are extruded aluminum corner braces left over from something I tore down years ago and hung on to. They're perfect for the job. I added an aluminum pulley bracket and a pulley from the scrap box. The pulley had a bronze bushing but I pressed it out and bored it for a couple inline skate bearings. The rope is a piece left over from replacing my mower starter rope.

http://i57.photobucket.com/albums/g227/DBAviation/Pulley-Brackets.jpg

I strapped together a block of Lyman lead bullet ingots for the counterweight. It weighs 9 1/2 lbs and seems to work well. The container off to the right is the reservoir for the Z-axis leadscrew oiler. I made it from a snap top film canister.

http://i57.photobucket.com/albums/g227/DBAviation/Pulley-Oiler.jpg