[tauscnc]

Hey guys,

Well I figured it would be easier to just start a new thread on my machine. I GOT IT TODAY!!!! YIPPIE.

Before we get started, I want to make sure I say the intent of this thread is to give an honest review. As many of you may know I got a KT-2525 that I returned do to workmanship.

MACHINE K2cnc.com KG-3925

I just got the machine and am at work so I can’t do much with it. However I have opened up the package and all I can say is A+ for packing. Man they really took there time getting this in the box. I asked that it be shipped apart and each piece is individually wrapped, etc. Screws are with the pieces. NICE.

This think looks HUGE! I have looked at the Y and Z axis and they look good. Again, I won’t know till tonight/tomorrow how everything runs but so far so good.

CNCRob have you gotten yours yet?

taus

[JavaDog]

[Chamm128]

Give him a break, he's at work. But there better be pics tonight!!!

[JavaDog]

Give him a break

Ok, but just this once!

Did you order their servo/controller package too? I'm curious because it looks like they use the same servos that I bought (Clifton). I am interested in seeing what type of performance they give (and with the PSU they put together).

[tauscnc]

Man those guys holding up signs look funny. Yes, this thread without pics does lack a lot :banana: I will get pics up tonight and as the days go on.

I did not get the servo package but am going to use 180 oz/in steppers (ones from my sherline mill) and I think it will run nicely. I am really thinking of getting these 270 oz steppers (http://www.homeshopcnc.com/page3.html) but I will see. Then I can put the other steppers back on my sherline. I will be using max voltage for the steppers and gecko drives.

So far things look good. I think I might have to open up the mount for the Y-axis that hold the mount for the ballscrew (man K2 really needs to get a part list out!!!!). I find when it is a little loose it is very smooth to move but when I tightned up the screws there is more resistance and the ballscrew sound a little rough. The linear bearings are awesome!

This is my first machine with ballscrews, linear bearings, anti-backlash screws, etc.

I will put it together tonight (heck I might even skip dinner) and get it running!

YIPPIE! :wee:

taus
www.cuttingedgecnc.com

[CNCRob]

I have not received mine yet, but on the ups tracking page it says out for delivery. Its usually around 7:00pm before they get to our house. Glad to see you got yours.

[CNCRob]

I finally got my KT-3925 CNC machine. Actually it came just 4 mins after my last post. I think it's a really nice machine so far. But all I have had the chance to do is start unpacking everything. It was very well packed by the way. The real test will be when I get it put together and try it out. I went out and bought a work bench to put it on tonight. I posted a few photos of what it looked like this afternoon. I should be able to post some better ones of it put together soon.

[tauscnc]

Hey CNCRob,

That is great news!! I am also putting mine together as I had them ship it unassembled. Very nice so far. I do find some backlash in the Nook ballscrews. Still putting it together.

will get pics up tonight.

taus

[tauscnc]

IT's ALIVE!!

I will write more about it soon but here are some pics. Mine has 2 extra cross braces that I had ordered with the Kt 2525 that they let me just keep. One is a bit short and I will put a shim on it.





(this is great, I can add photos! Thanks Paul for such a great site!)

hehee
Ummm like what do you wanna cut?

Man this thing is HUGE!

taus

[JavaDog]

CNCRob, can you do me a big favor? Could you take some close up internal pictures of the PSU/Control Box? I am going to be using the same transformer that they use, and I just want to see how they did it. I'm also interested in where they got that nice AC input block with the switch.

If it isn't too much trouble. :cheers:

tauscnc: Looks great! No tolerance issues on this one? Can't wait until you get this dialed in, curious to see how the accuracy is. Congrats!

I see you are using the same transformer from MJPA too, and wiring it in series like me.

[tauscnc]

Hey JavaDog,

Yeah, it is the same MJPA transformer. What I don't know is if you wire transformers in series do you cut the amps then? I am thinking of mounting the Geckos on the axis to keep the wire motors very short but am concerned about the dust and dirt getting into them. I could also just build a box like the one CNCRob got. I think if K2 routed the box with X Y Z and their name that would of looked really cool Heck, he can just route it himself now. If I make one I am thinking of making it with the clear polycarbonate sheets. I will have to see.

My biggest concern is making a new table for it, getting an enclosure made, mostly KEEPING this thing and the basement clean. Somehow I see chips of material ending up all over the house.

I will try to cut something today. I notice the X axis needs to be tightened (the end nuts need to be tightened). I think I also need to tweak the mount that mounts to the X and Y ballscrews. The Z axis seems dead on but I have not measured it yet.

I need to figure out how many steps I need for 1 mm movement (Gecko microstepping)... any ideas before I start throwing numbers out?








thanks!
taus

[tauscnc]

How do I make the photos thumbnailed?

thanks
taus

[carlnpa]

You might try 393.70 step/mm to start.
When you get a chance would you measure the backlash in your Nook ballnut.
Your machines arrived in better condition than mine did.

[cncadmin]

How do I make the photos thumbnailed?

thanks
taus

You can't yet, when linking from the photo gallery, you would have to upload them to the thread. I'm working on a fix.

[tauscnc]

Thanks Paul.

Carlnpa,

My KT-2525 had some banged up nicks, probably from FexEx but the box they sent my base was thin and not well packed. I wrote to them about that and asked that my machine be sent disassebled. I did not think UPS could handle such a large item without killing it And yes one of the boxes was bashed open but luckly it was where all of the padding was. The machine arrived very good.

I would suggest anyone getting these larger machines to get them disassembled. But there is also NO documentation with it so you have to go off the pics. It is not tough, everything fit well. CNCRobs seems to have come out ok.

I will check the backlash soon. I do notice there is more in it then the leadscrew I thought ballscrews where not spose to have much of any backlash.

I am surprised at how noisey they are also. They sound almost gritty..but I hear as long as the balls are moving and not sliding that is fine ??

Is there any grease that you use on them or do you just leave the screw dry?

thanks
taus

[tauscnc]

Are ballscrews very gritty?

I find if I turn the screw counter-clockwise it's pretty smooth. However when I change direction (clockwise) it is tough. It like they are getting stuck and I feel like I am going to break them. They loosen but get stuck again.

So far I don't see the luxary of ballscrews or are these Nook ones just cheap? They list thompson on the website but nook is what I have. The leadscrew on the Z axis is silk.

There has to be some grease they need...

UPDATE:
I called Nook and they said to use E-900 lub. The ballscrew is a standard roll screw and the info on the nut is here (SBN10325)http://nookindustries.com/ball/BallSRTInfo.cfm?id=15

taus

[ckirchen]

Tuaseef,

When I ordered my ballscrews and ballnuts from Rockford, they were extremely gritty. I dismantled the nuts and sprayed them with WD-40 over a white paper towel to see what was in there. Lot's of dirt, some grease, and even a few full chips came out.

I ordered another ballnut from Thompson a while later and it was dirty as well. Not as bad as the Rockford, but still in need of a good cleaning.

My advice: before you install a ballnut, take it apart and clean it thoroughly. They’re not hard to put back together (http://industrialhobbies.com/howto/p...ed_ballnut.htm). And, wipe down the entire length of the screw while you're at it.

Chris Kirchen

[HomeCNC]

I have used the rolled type ball screws on all my CNC equipment. About the ball screw, I have received some that looked clean on the outside and I have seen some that looked like they had some kind of flakes on the outside of the screw. Like it was burned in the heat treating process or something. I don't know enough about the process of case harding of these screws.

I took a wire brush to the screw to clean off the flakes. It is a good idea to dismantle the ball nut because it also is case hardened and could have the same flakes inside.

Also do lube the screw.

[Morgantech]

My biggest concern is making a new table for it, getting an enclosure made, mostly KEEPING this thing and the basement clean. Somehow I see chips of material ending up all over the house.

taus,
I purchased a custom built 25"x50" unit from K2CNC. Both kevin and Ron have been a great help!
I have attached a couple images that show how I put together my setup. The old steel tube drafting table works great. I used plastic laminated 3/4" aircraft ply w/T-nuts for a hold down table and my own clamps. The dust collection system, which I fabricatred, works great for cutting flat material such as crabon, ply and 1/8" alum. I use a 1 micron, 1600CFM dust collector attached to the bottom of the drafting table to keep the dust contained within the 1/4" plex cage.

Mike

[cbass]

Nice setup Mike.

I'm thinking of a similar setup using retaining walls at the edges of the cutting surface that just clear the gantry to limit swarfing on the x axis rails.

Man, just looking at what you guys have done/are doing to setup your machines is almost dicouraging. Even after I get my machine it will probably take a good month to get everything assembled/hooked up

swarf guard
way covers
sealed machine case
spindle mounting
table surface-including hold-down system for parts-
fresh air / exhaust air
machine stand

ahhhhhh... are we there yet?


Carlo