[mattmark]

bob - thanks for hooking up the g-wizard demo.. should be helpful, although it seems that my rpm max is too slow :P

hey jeff,

i guess it's a matter of some trials and figuring out if it's worth the cost.. i figure compared to everything else, the machining and stock cost of aluminum is cheap compared to the machine/ballscrews/drivers/servos/steppers... but i guess waste is frustrating and adds up =)

what does everyone think of the enclosure setup, most specifically the bolting system? it'll be a 10" length 1/2" bolt with washers (do i need lock washers or compression springs?)... the enclosure is plywood/fiberglass.. the wooden box underneath the mill is a crowded 2x4 (vertical) frame with 5/8" plywood all around. i'm just wondering if i need to silicone the pucks in? or will the weight and compression block most of the coolant? i've pretty much built the enclosure base and fiberglassed it (been staying up way too late working on this stuff)

and what about this for a pump? i'm thinking about approx 12 feet of "pipe" and tubing.
http://www.homedepot.ca/webapp/wcs/s...k=P_PartNumber


Matt

[mattmark]

here's some pix of the idea i tried with the steel pipe as a spacer for bolting the base (didn't work)..

also, since setting up the stand in it's new location, the cord wasn't long enough (only 40ish inches?), so i bought 12 foot 14/3 cable for it.

[mattmark]

also, here is my flood coolant enclosure.. drying as we speaking.. it's frustrating working with something large enough that you can't really work around it.. oh well. definitely one of my poorer products.

5/8" ply-fiberglass cloth+resin and gel coat.

we'll see if the bolt-through works for mounting.... also trying something different for the drain..

[kawazuki]

Ok - i'm the one who has to ask.......why's it asymetric?

[pete from TN]

it has to be!! Mine is the same way, when you go cnc you add a motor and motor belt drive assembly to one side of the table and you have to have room for that. This one looks almost exactly like mine only mine is 3/4 inch plywood. It is still watertight and working well. Glad I went with the plywood/fiberglass build. It is actually pretty easy to do..... Just need to get some plexiglass walls up on it soon.... peace

[mattmark]

hey kawazuki,

yup, i think pete summed it up there, i just hope i gave enough clearance for the eventual motors (it's funny when i don't actually sketch/plan my wood working and shaving an inch here or two... can come back to get me)

so i was looking at hoss' suggestion for a lathe attachment motor and controller..
http://www.littlemachineshop.com/pro...311&category=5
http://www.littlemachineshop.com/pro...3042&category=

when i called LMS, chris suggested this combo:
http://www.littlemachineshop.com/pro...3062&category=

looks good to me on paper, although earmarked for a grinder.. make any difference at all?

Matt

[RalcoBe]

My Zay7045 has exactly the same internals.
How to make a Chinese machine twice as good? Tighten the bolts and screws :-)

[mattmark]

haha - funny enough (or maybe not funny at all), when i opened the electronics case, there were a whole bunch of loose nuts & bolts.. no idea what those are for

[mattmark]

well, it's been a little while since my last update,

got all the pump/plumbing in order for the enclosure..

i was going to post a vid/photos, but i realized i have a leak.. not sure from where..

how important do you guys think it is to bolt the base to the enclosure and the stand? i that's the source of my leak (i've siliconed the pucks, etc)..

i'm tempted to start from scratch as i'm trying to figure out the best geometry for the enclosure (too much pooling where the base goes, etc)..

[blighty]

how important do you guys think it is to bolt the base to the enclosure and the stand

i think this could be a wise move. don't now about any one else, but my RF-45 is mounted on a wooden table about 2 foot high,1inch base with 4 x 4inch frames and legs. when the table stops after a long (well any) rapid move, the table stops but the machine Carry's on going. so when it starts the next cut i get wobble lines in the work.

I'm moving house soon and when i get the mill up and running again it will be bolted to a concrete plinth. hopefully this should stop the wobble.

[mattmark]

hey blighty,

thanks for the input - i think i have to just make sure i seal everything properly when i bolt the stand down, whether it's silicone or rubber washers, etc

i made a huge mistake by not really ensuring that i was drilling vertically when i was making the bolt holes in my enclosure.. lesson learned (don't cut corners).

i've received my 4th axis gear (motor, control, gears and lathe head) from LMS..

now, to research the cnc stuff:

are most ppl of the rf-45 variety going with roton 3/4" type of ballscrews, 5tpi? i'm thinking gecko g320x and keling KL-34-180-90 1125oz servos, geared down to 4-1... i've heard various things about the encoders (like issues with the old us digital ones) - any comments/recommendations? for a 4-th access what type of power do you think is needed? i'm thinking 1125 is way overkill for this..

been looking at the keling or antec power supplies, 72V looks like it makes sense, but what wattage should i be looking at for this system?

still collating info and reading... would love to hear your ideas,

matt

[RalcoBe]

The gecko delivers max. 20A.
In DC motors, current is linear to Torque (Nm or Oz-In)

Your maximum torque at 20A will be +-450 Oz-In. Nothing more.
Advantage of taking big servos, who can't be operated to their maximum,
is their bigger nominal Torque. (must be +-200 Oz-In for yours)

Big advantage (for me) of the g320xGeckos is the pulse multiplication
(slow controllers can command fast pulsetrains, so more speed)

[mattmark]

hey ralcobe -

any other options out there with more current ability than the 320x?

so for a given motor, ie 1125oz/in servos with a 90v/40a max, an increased current from 20a to 40a will give twice the torque holding ability?

matt

[RalcoBe]

Yes, you can find the Maximum Current (@ maximum Torque) in the datasheet of the motor. Only for DC motors. AC / BLDC / Steppers is another story.

I think it's better to look at what nominal Torque you need. Column speed , friction and PID settings determinate this.

.

[Flenser]

I have the Keling 1125oz servos with the US Digital encoders (I read the same stuff about them, but decided to take a chance), the 320x drivers, C11G breakout board and AnTek 70V 1KW power supply. Nothing is hooked up yet, though. I've been distracted reworking some of the parts I made poorly for the lathe CNC conversion. I also just ordered an Intel Johnstown Mini-ITX motherboard from Logic Supply that will fit in the enclosure. I hope to get the enclosure together and ready to test this weekend.

If you want a higher current drive, there is the Rutex R2020.

I'm half planning to use the RM2505 Chinese ballscrews on ebay from linearmotionbearings2008, mostly because they are so cheap. He will also machine them to order, and my lathe spindle doesn't have a large enough opening to slide any suitable screw through. Any ideas on machining the screw with the mill?

Jeff

[mattmark]

thanks ralcobe - that might be interesting exercise in terms of determining exactly what i'll need for the future (which at this moment, not sure).

hey jeff - i eagerly wait upon your test trial of the motors. understandable in regards to reworking pieces. so are you pretty much set with all your electronics (ie motors, drivers for each, BOB, power supply)?

i noticed there are "rutex motherboards" (ie r2020) - what exactly are those for?

the screws look interest from linearmotionbearings.. what material are they using?

[Flenser]

Yea, I think I'm set with the electronics. I still have limit and estop switches to get, and will probably make a (hopefully wireless) control box.

The motherboard is sort of a Rutex specific breakout board. It lets you plug in 4 r202 drives into the PC without a lot of wiring.

The screws are C7 and rolled. The ballnuts appear to be ground. I'm using the smaller RM1204 and RM1605 in the lathe.

Jeff

[mattmark]

hey jeff,

back to your machining the screw without a mill - i was wondering what most people do.

i guess they have access to another mill/lathe while doing their conversions (more excuses to have a bigger mill and a smaller mill?). do you have another mill? i'm thinking i need some other machine to build the one-shot oiler, etc..

otherwise, not sure how to get what you need done, without having a larger spindle bore on your lathe.

i'm currently reading up on a couple of conversions - pete's and bob warfield's.. lots to read and mull through.

[Flenser]

hey Matt,

I machined the screws for the lathe on the lathe. It was my first experience with hardened steel and there was much comical trial and error. I eventually settled on getting the basic shape with an insert type of tool and to finish it with a Dremel tie wrapped to the tool holder. I also tried the trick of using an angle grinder to break through the hardened skin, but it was pretty hard steel all the way through.

I also made a mount for a mill attachment and milled some of the brackets on the lathe. Actually, I should say I made the bar for the QC tool holder and one bracket for the CNC conversion, then ordered the mill

The trouble with cutting the screws for the mill on the lathe is two of them will be longer than the lathe bed and also won't fit through the spindle. When I cut the Z-axis screw for the lathe I slid it through the spindle and made a bearing mount that kept the free end from whipping about while I was finishing the other end. Hey, maybe this is a good excuse to buy a bigger lathe!

Jeff

[RalcoBe]

I once saw somebody who attached a ordinar disc grinder to his toolholder on the lathe.
Lathe on, grinder on, start. The results were mutch better than expected.

Some may laugh or turn blue due for safety concerns,
but this is sometimes the only kind of solutions for underbudgetted people like me :-)

.