View Full Version : Scary, scary job
I'm working on the base plate for my mill project. It was rough cut from two pieces of 3/4" 6061 screwed together. The edges need to be milled square. This is how I did it. It actually worked with only one minor "tool ate the work" episode. I didn't notice the gibs were loosening but the damage was minor and will not have any impact and will be completely hidden. In all it worked well.
http://vts.bc.ca/img/scary1.jpg
[This message has been edited by Evan (edited 07-04-2004).]
Mike W
07-04-2004, 10:07 PM
Way to go Evan! That does look scary.
lenord
07-04-2004, 10:25 PM
Evan,
Congrats on escaping reasonably unscathed.
The last time I did that, my plates had great big holes centered in them. I have a round column mill though. I'll likely have to do more of them.
Do you think that adding taller material between the vise jaws and the workpiece will make it more stable ?
I was thinking of those giant angle plates you can get for cheap too.
Lenord
[This message has been edited by lenord (edited 07-04-2004).]
Rustybolt
07-04-2004, 10:38 PM
The machining gods have smiled on you. Looking at the setup, I'd think doing it in the table saw would be just as accurate.
had ir been me I'd be explaining to the emergency room doctor just how I happened to have an endmill protruding from my forehead.
Please be careful.
I managed to get the side to side dimensions to within .010" parallel. It isn't critical at all since all parts that mount on the base will be adjustable. I just am not happy with rough cut pieces even though it would work just as well.
BTW, I don't have a table saw...
wierdscience
07-05-2004, 06:57 AM
Holy s---! http://bbs.homeshopmachinist.net//eek.gifTalk about your unsupported,over extended workpieces http://bbs.homeshopmachinist.net//biggrin.gif Tell me,did the vise live?
Oh,congrats,you made that jam up good drill press look like it came from JET with all that white paint,couldn't find any green or what? http://bbs.homeshopmachinist.net//biggrin.gif
The DP is actually grey but is overexposed in this pic. The vise is ok. The only reason it worked is the mass of the plate and the fact I took very light cuts at high RPM. The DP does 2200 in high gear. One thing that helped is that when I reached the end of travel of the X/Y table I just swung the DP table over another 6 inches to continue the cut.
Rustybolt
07-05-2004, 12:28 PM
Does the table tilt 90 deg?
A skill saw and a straight edge would have been safer, faster and as accurate if you couldn't find a table saw. Set ups like that one can go bad very fast and if you are standing close enough to turn the crank on the stacked slide you could get more than chips in your hair. Glad you survived. The photo would be a good one for some kind of safety poster. Add some ketchup.
No table tilt. Cass, I didn't get the feeling that it would go haywire in a dangerous way. It was pretty stable. That drill press is very rigid even though the setup isn't the best. I don't think I could get a close with the skill saw, it leaves a pretty rough cut and it would have to be cleaned up somehow. I don't relish the idea of draw filing for days.
bikepete
07-05-2004, 03:27 PM
Couple of maybe-possible alternatives:
How about using the lathe as a shaper - might work nicely if the saddle movement is long enough to clean up the edges at one pass. You'd have to clamp the alu to the lathe bench or something so the edge to be cleaned is parallel to the bed, and extend a tool out to it. Could be tricky, depends on your lathe setup.
If you've got some sort of toolpost milling spindle setup this would save some cranking of the handwheel as you'd do for shaping.
Or - clamp the plates flat to the saddle of your lathe, and move the DP over to stand on the floor next to it, and lower the head so that you can machine the edges using the side of a large cutter. Kinda like using the lathe as a co-ordinate table. Whether this is any better than the rig shown above would depend on how easy it is to clamp stuff to the lathe saddle I guess.
Cheers!
Pete
I did think about using the lathe but that plate weighs about 50lbs and would be a bit much for the SB9. As for moving the DP near the lathe, ain't going to happen. The lathe is in the basement and the DP is in the garage. It weighs about 600 lbs.
BJim Shell
07-07-2004, 04:28 AM
The sound you heard was me gasping!! I have cut 4" holes in 1/8" alum. in d/p without c drill in single tool flycutter for speakers but had 5 ft. leverage. Could hear the chatter a 100 yds. I was told. Jim
wierdscience
07-07-2004, 07:16 AM
I did use a router and a sharp 3/8" carbide bit once on some 1/2 aluminum plate about 6' long,it came out good,but it did take awhile,I could only get a 32nd at a pass without it chattering.
dsergison
07-07-2004, 08:42 AM
<font face="Verdana, Arial" size="2">Originally posted by Evan:
.....I didn't get the feeling that it would go haywire in a dangerous way......</font>
So, which is it? a Scarry Scarry job, or not?
--just teasing you.
you sure make an art of how to make do Evan. http://bbs.homeshopmachinist.net//smile.gif
dsergison
07-07-2004, 08:46 AM
my favorite howling squealing obnoxious setup was parting a street light pole lengthwise on a b'port.
Not dangerous to me. Possibly scrapping the part or breaking the tool was the scary bit.
I just finished calculating the cutting schedule for the parts for the column and various other pieces. I have a 16 foot length of 2" X 3" 1/4" wall box section 6061 t6 aluminum that I bought still in the wrapper for scrap price http://bbs.homeshopmachinist.net//biggrin.gif http://bbs.homeshopmachinist.net//biggrin.gif I will have maybe 1" left over and a bunch of swarf. Mill will have around eight inches clearance from end of tool to table. Now I have to figure out a setup to flycut the ends of 9 pieces of that rectangular stock on the lathe, eighteen ends. Definitely worth spending some time on a good setup.
[This message has been edited by Evan (edited 07-07-2004).]