[jid2]

Ordered a set of 4" CNC vises from Shars. They were cheap, people seem to think they are OK, I think they will do what I need them to.



Also bought a new compressor, pretty excited about it. California Air Tools ultra quiet, 10 Gallons, 5.3 CFM @90psi with an air dryer and after cooler system. My existing 20 gallon compressor is standard loudness and I hate it coming on when I'm working late at night. The new one will also support the required 5 CFM that most VMC's need as well as the filtering and drying.

Here's what it looks like.



http://www.youtube.com/watch?v=MEpsHjlxl50

[gd.marsh]

Jid2,

I've got 2 of the very same vises in 6" and they work fine for me. Not the smoothest when cranking in or out, but once set up it's usually just a half turn or so on the handle to change parts anyway.
One thing I've done is make myself a whole batch of soft jaws that I always keep on the vises all the time. Even for general work, when I set one or both up to make parts I clamp a 1/2" or so piece of square stock deep in the jaws & then run an end mill across the inside top edges of each jaw leaving about a .100 X .100 step. That eliminates the need for parallels & insures that my stock is sitting in perfect alignment with X and perfectly flat with Z. The notch does continue to grow a little wider & deeper over time (re-skimming every time I put the vise back on the table) but I get lots & lots of use before they need changing.

Nice compressor .. Very Quiet! ~ My big 80gal job is parked in it's own little shed outside the garage so I can still think when it's running!

Gary

[jid2]

Have you seen monster-jaws. They are so cheap its not worth building them from stock. I too am a fan of soft jaws and plan to do them for these.

Hows your machine going, what have you been building on it?

[gd.marsh]

Not doing much with the machine lately in the way of production stuff .. just my own 1-off hobby projects.
Been working on the 'swing-out tool setter' when time allows. Now on the 3rd iteration of that, but I think I've finally got it nailed.
Still some work to do to complete the latest version, but have to leave for a few weeks so not going to be able to finish until I get back.
I'll most likely post another video on my thread once it's complete.

You're machine is looking great & is doing some impressive cutting in your videos.
I'm still not running mine full out. Certainly has the potential, but after a few crashes, I'm a little gun shy when it's zipping around like crazy.

[j_pniewski]

Got 2 of the 4" Shars vises on the G0704. Took the hand wheels that were removed from the mill, machined a hex shaped hole and replaced the handles that came with the vises. Can tighten them quite hard, especially using 2 hands, but there is still over an inch of hex sticking out if you needed to use the original handle.
Joe

[rob_b]

My budget envies your budget!

I recently picked that vise up from Shars for my G0704 as well. Mine required a complete breakdown as it was still full of casting sand but it cleaned up reasonably good. My only real complaint is that the bearing pocket for the screws thrust bearing is way too big so its tough to set the proper pre-load while keeping the runout in check. Some day I'll make a brass bushing that takes up most of that slack. One other thing I found funny was that they misspelled "Shars" on the tag, it read "Shais".

I only get email alerts on one build and this on is it, keep up the good work!

[Mad Welder]

....ALso bought a new compressor, pretty excited about it. California Air Tools ultra quiet, 10 Gallons, 5.3 CFM @90psi with an air dryer and after cooler system.......

Wow now that IS a quiet running compressor.....nice purchase!

[jid2]

Compressor should be here Wednesday, can't wait. Vises will be here tomorrow.

Did a bit of machining this week. First was a work project, carving out some tiny little bobbins for winding a custom coil. They have a massive undercut that leaves .020" thick flanges.






Coil Bobbin - Tiny Part Machining - YouTube

Next up was a series of errors on my parts that created a nice little video called things not to do while machining.

1. Cutting vise jaws, aka putting in the wrong parallels.
2. Mis-cutting stock to increase depth of cut, aka 2hp cut.
3. Not verifying gouging when using a slotting cutter, aka making scrap.


I ended up testing the limits of my 2.0hp motor on error number 2. I had my standard roughing cut set, but added more material with my cutting/programming error. My intended cut was .80" deep and .060" wide, running the 1/2" 3 flute tool at 6600 RPM and 90 IPM. What happened is that I cut my stock .100" longer than I had programmed in the stock definition, so the width of cut jumped up to .15". This turned into a 1.96 HP cut at 9.something Cu-In MRR. The spindle did bog down, but it made the cut and created some seriously thick chips for this little machine.

Anyway, I'm not proud of my lack of focus programming my way into all these problems - but they are good for learning.

I did have some fun clearing out the center section of these parts with an adaptive clearing toolpath that was cutting with my 1/2" 3 flute at about .20" DOC, .20" WOC at 100 IPM, with 150IPM on the non-engagement linking moves. I think there's still more speed available as well.

www.youtube.com/watch?v=XtUjdVdg40Q

[jid2]

The new compressor is sweet. SO quiet. Here are some photos of it.

Nice wooden crate.



Air drying system is included.



Smaller than the old compressor and higher flowrate - with less noise. Just add $$$.



I had some serious issues with trying to friction stir weld instead of cut this weekend. The problem tool was a 1/4" carbide 3 flute coated endmill doing slotting cuts. Spindle speed was 6800 RPM, and the cutting feedrate was 30 IPM. The tool would cut OK ramping into the part at 15 IPM, but as soon as it was at depth and it kicked to 30 IPM, it would load up almost instantly and I would have to be fast on the e-stop.

I made sure the Fogbuster was directly on the tool, with good air pressure and coolant flow, but it would just load the flutes nearly instantly at 30 IPM. It did it in a pocket and a profile - repeatably like 4 times. I ended up knocking the feedrate down to 15 IPM and it cut fine.

The chip load at 15 IPM is crazy low though. Perhaps the 3 flute tool just can't clear itself and I need to use 2 flutes. I know that the 1/8" tool likes to be 2 flutes in Aluminum, but perhaps anything 1/4" and smaller wants just 2 flutes also.

[TiagoSantos]

Could be worth trying lower RPM as well, for hopefully less heat and tendency for chips to stick/weld themselves to the tool?

[rlockwood]

My experience agrees with yours, though I'd expand it to say that you're better off taking a heavier chip with a 2fl tool, up to 1/2", rather than 1/4" as you suggest.

[jid2]

So just try a 2 flute seems like the answer. Looks like feeds for a 2 flute at 6800 RPM go from about 13 IPM to 32 IPM for slotting. So I'll give that a try. It's crazy that the number of flutes is so critical. I mean these 3 flutes jam instantly!

[rlockwood]

So just try a 2 flute seems like the answer. Looks like feeds for a 2 flute at 6800 RPM go from about 13 IPM to 32 IPM for slotting. So I'll give that a try. It's crazy that the number of flutes is so critical. I mean these 3 flutes jam instantly!

Yeah, i'm not sure why the small diameter 3-flute tools have become so prevalent in the market. I have never had lots of success with them, and experienced largely the same results as you-- there simply doesnt appear to be enough clearance to get the chip out. You didnt list your depth of cut (unless I read over it somewhere) which could be playing a factor here as well. I'm not sure where the 13IPM number is coming from; In a slot, i'd run .125" deep and ~30ipm@600rpm, and wouldnt expect any issues at all.

[jid2]

Depth was .125". I'll have to order some 2 fluters.

[LUCKY13]

Jid2, your right the three flute in a 1/4" end mill just doesn't leave enough room to move the chips out "when slotting". Even with a bigger end mill a 2 flute would be best bet, again when slotting. When going with a 1/2" or bigger end mill when doing just outside sizing of a part the three flutes really work quit nice, but as soon as you get down in a hole/slot it gets more dependent on clearance and lots of coolant. There really needs to be some heavy coolant flow if possible. I didn't notice what type metal you was cutting (maybe 6061), if so, it can be a bit gumming depending on the batch. If it was a even lower grade some of them can really be gumming.


The difference between full on high pressure coolant and a fogger/air system really shows up in this exact type of job. Its been a while sense I have read your build and I am not sure if you have a full coolant system, if not it would pay to go that route if your going to cut much aluminum. Even if, a two flute is going to be your best tool when slotting. A end mill with the right coating will also help, but once you get the right clearance, plus the coolant you can get by without a coated cutter.


That air compressor is sweet! I don't like a noisy pump either, and when the shop is close to the house they can really bother me. I tell you, you just keep building your system better and better. IMHO I think you may have the best sounding spindle/motor setup going as far as RF-45 machine. It sounds more like a Haus spindle ( I hope that's a complement) instead of a modified RF-45. If I can get even close to the results of yours when I mod mine I will be pleased.


Good work
Jess

[rlockwood]

By the same token, a 10 flute can be used for incredibly quick high finish in periphery milling.. Just make sure it doesn't enter any real tool engagement :-)

I also concur with the case for real flood coolant, and at as high of a flow rate as you can manage. Air and mist are not equal, or even close, in aluminum. Its better than nothing.. But I doubt it's ever really the determining factor between having a tool failure and not.

[MetalZilla]

Nice Garage Shop! I once had a Haas Mini-Mill and Haas SL-10 Lathe in mine.

[jid2]

I don't plan to get to flood coolant on this machine. Although I really just need encoder housings as I have the plumbing, pump, and control.

A super mini mill would have all that stuff!

I'm getting ready to run some delrin at 180IPM, tested already cutting air and it looks good.

[LeeWay]

You won't need coolant on Delrin.

[Albert588]

Next up was a series of errors on my parts that created a nice little video called things not to do while machining.