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LAN_403

Hazmatt_(The Underdog)

Sat Dec 06 2014, 01:50AM

Registered Member #135 Joined: Sat Feb 11 2006, 12:06AM
Location: Anywhere is fine
Posts: 1735

I would fly-cut the surface rather than using an endmill. I have a heatsink that we fly cut on a large machine and it came out beautifully. We're only taking half a mil off anyway to true-up the surface here, so it's fairly quick and a large 3" pass.

But what Kizmo is saying is that is not going to make a difference, so then should he shim the bottom of the table?
If you have a known parallel mounting plate, I guess shim would be a good answer because you can get precision shim, and the table is a bolt-on so that would be possible.

I've never setup a machine before, I do my best with what I have as well, and I can get pretty good results on non-critical things. I'm learning and practicing as well with my Atlas mill, and getting more tooling for my drill press.

Dr. H.

Mon Dec 08 2014, 06:23AM

Registered Member #931 Joined: Mon Jul 30 2007, 05:25PM
Location: Bulgaria
Posts: 486

Hi guys,

What Kizmo is saying (if I understand correctly) is that you must have a true machine (everything is aligned at right angels) and then to shim the surface.

Most likely I will also use fly-cut - depending how much material I have to take off.

Cheers

Hazmatt_(The Underdog)

Thu Dec 11 2014, 04:44AM

Registered Member #135 Joined: Sat Feb 11 2006, 12:06AM
Location: Anywhere is fine
Posts: 1735

Before you fly-cut, use a dial indicator and take some measurements. Maybe zero in the center of the plate, and see what the corners read, then repeat the procedure after the fly-cut and see if there is any improvement.

Also, you could use layout fluid before the cut to "see" where you have been, and also you would want to go just deep enough to scratch off the marking, just my feeling on that one.

Dr. H.

Mon Dec 22 2014, 07:43AM

Registered Member #931 Joined: Mon Jul 30 2007, 05:25PM
Location: Bulgaria
Posts: 486

Hi guys,

the power supply for the servo motors is ready. It is around 40V 30A total, non stabilized. The box also includes the relays for air, oil, water pumps... soft start and so on ...

Cheers

Linas

Tue Dec 23 2014, 03:11PM

Registered Member #1143 Joined: Sun Nov 25 2007, 04:55PM
Location: Vilnius, Lithuania
Posts: 721

nice "old style" assembly, like in aircraft military equipment

Dr. H.

Sat Jan 03 2015, 08:34PM

Registered Member #931 Joined: Mon Jul 30 2007, 05:25PM
Location: Bulgaria
Posts: 486

Hi guys

some progress - the table is mounted, all of the drive motors are mounted, and the spindle mount is ready. Also the limit switches are done. Cheers

Patrick

Sun Jan 04 2015, 04:50AM

Registered Member #2431 Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639

thats real nice aluminum plate.

cjk2

Thu Jan 08 2015, 09:34PM

Registered Member #51 Joined: Thu Feb 09 2006, 04:17AM
Location:
Posts: 263

Could you show more detail of the spindle? Did you machine it yourself?

Dr. H.

Fri Jan 09 2015, 06:58AM

Registered Member #931 Joined: Mon Jul 30 2007, 05:25PM
Location: Bulgaria
Posts: 486

Hi guys

Thanks for the nice words.

cjk2 - it is a home made automatic tool change spindle for BT30 tappers. Will be posting detailed pics soon but still ironing out some of the mechanical details (waiting for two shims from Germany) and want to be sure it half works before I post it. Stay tuned

Cheers

Dr. H.

Sat Jan 10 2015, 08:14PM

Registered Member #931 Joined: Mon Jul 30 2007, 05:25PM
Location: Bulgaria
Posts: 486

Hi guys

as promised here is the assembled spindle. It is an automatic tool change spindle, using belleville springs and ball type gripper. It is built on the heavy side - deliberately using a bit bigger bearings. All of the components of the gripper are heat treated. The bar for the springs is grinded to provide the needed surface. The spindle will be lubricated / cooled by small oil station. A pneumatic cylinder is used for releasing the tool.

Just assembled the spindle and tested with very cheap bearings - the runout of the tool is quite big - about 0.09mm with 80mm long tool. As the tapper face is turned on the lathe I am pretty happy with the results. I usually work with much shorter tools so it should do the trick for now. Most likely will be grinding the face of the cone when I put good bearings (instead of the 7$ per 7209 bearing that I use in the moment

). It is possible that some part of the runout is due to the bearings.

The concept seems to work - it successfully grips and releases the tool. remains to measure and tune the needed pull force in the static position. Also the rear cap will be remade with few changes and from steel as the alu used for this one turned out to be really crappy and the results are really ugly.

This thing turned out to be one of the most difficult parts of the whole build and still has a lot of work to be done to come to the final product.

Ok here goes the pics. P.S. the spindle and mount weigh 31 kilos ....

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