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howecnc
08-23-2010, 06:59 PM
Right now I am monitoring this forum at least once every two days.
If anyone has questions please feel free to ask.

Howecnc

SWATH
08-23-2010, 11:09 PM
Hi Chris,

I have some to start off.

1. Do you find the touch screen worth it?
2. Do you notice the extra HP or faster speeds over the Tormach?
3. Do you like the full enclosure style of the Mikini over the open style Tormach?
4. What do you manufacture and do you find the Mikini to significantly increase production over the Tormach?
5. What Cam software do you use?
6. How does the Mikini handle hard steels
7. Do you feel servos would be a worthwhile upgrade?
8. What do you like and dislike about the Mikini over the Tormach?
9. Did you get the Mikini tooling package or any other options from them?
10. How realistic are small production runs on this size machine (<300 parts assuming something about as complex as 2"x3" steel ballcock)?

Thanks for your willingness to answer questions.

howecnc
08-24-2010, 04:09 PM
1. Do you find the touch screen worth it?
I like not having to need a clean place for a mouse to sit but you do need to keep one finger clean

2. Do you notice the extra HP or faster speeds over the Tormach?
the faster rapids and smoother motions are great but I don't believe 1hp makes all that much difference.

3. Do you like the full enclosure style of the Mikini over the open style Tormach?
The enclosure was a must for the second machine as it was closer to where I program. I fully intend to enclose the Tormach eventually.

4. What do you manufacture and do you find the Mikini to significantly increase production over the Tormach?
I manufacture a wide variety of R&D parts mostly and I use the machines as a team to prevent breaking down operations to setup new ones. If a part takes four operations to make I can keep all the tooling and fixtures in place if needed. If I only need to make 1 piece and ruin it on the last operation it won't be such a set back.

5. What Cam software do you use?
EdgeCAM

6. How does the Mikini handle hard steels
I have cut 4140 with the Mikini so far and it seems to handle it a little better than the Tormach.

7. Do you feel servos would be a worthwhile upgrade?
For small machines like these I don't see where the servos are worthwhile and I also guess it would be specific to the needs of surface finish for the parts being made.

8. What do you like and dislike about the Mikini over the Tormach?
I like the enclosure, the accuracy, the sound and the rigidity.
I don't like the website and the lack of posted information, the Tormach is a bit easier to setup a job in.

9. Did you get the Mikini tooling package or any other options from them?
I got an ER25 collet chuck with a set of five collets.

10. How realistic are small production runs on this size machine (<300 parts assuming something about as complex as 2"x3" steel ballcock)?
That depends on the creativity of the guy programming the job.

mcphill
08-25-2010, 05:16 AM
Thanks for your participation on the board.

I just sent Phil my final payment on Monday, so I should have my machine in a couple weeks...

SWATH
08-25-2010, 11:24 AM
Thanks for your participation on the board.

I just sent Phil my final payment on Monday, so I should have my machine in a couple weeks...

Of course we want a full report with pics and video!:D

pkelecy
08-26-2010, 08:20 AM
7. Do you feel servos would be a worthwhile upgrade?
For small machines like these I don't see where the servos are worthwhile and I also guess it would be specific to the needs of surface finish for the parts being made.

I would expect servo's to position more precisely, although the difference may be minor. However, they're also much more energy efficient. So for the same input power (which could be limited if used in, say, a home shop environment) you get more output power (i.e. can make faster feeds or deeper cuts). Conversely, it uses less power for the same work. So if you run the machine a lot, it could make a noticeable difference in your electric bill.

I guess it all depends on price premium Mikini charges, but definitely worth considering, I think.

SWATH
08-26-2010, 12:04 PM
I would expect servo's to position more precisely, although the difference may be minor. However, they're also much more energy efficient. So for the same input power (which could be limited if used in, say, a home shop environment) you get more output power (i.e. can make faster feeds or deeper cuts). Conversely, it uses less power for the same work. So if you run the machine a lot, it could make a noticeable difference in your electric bill.

I guess it all depends on price premium Mikini charges, but definitely worth considering, I think.

True, I know the servos are more power efficient but I don't know how dramatically that would translate into the electric bill. The upgrade cost is $1000 per axis. I'm tempted but but that sounds kind of high (although I don't know much about it). I was also concerned as I read somewhere that the stepper motors will hold their static position with much more force than servos, although the servos have like 3 times the power.

I like that servos are quieter (I'll have the machine in the house). I like that they are faster since I plan on doing production. Potentially more accurate and use less power. Also If I can upgrade the 4th axis with a servo I may be able to do faster turning operations like fast single point threading.

My main concerns are if all the added speed and such will really be useful on a 16x16x10 travel work space and if the 4th axis can be equipped with a servo and if so can it get a decent RPM. Of course the cost, $4000 for XYZA.

SWATH
08-26-2010, 01:34 PM
Also Howecnc intimated that one could potentially get a better surface finish with servos over steppers.

pkelecy
08-26-2010, 03:11 PM
True, I know the servos are more power efficient but I don't know how dramatically that would translate into the electric bill.

That would be hard to say without knowing more about the parts you plan to make, the load they place on the servos during milling, how many hours a day you expect to run, etc. But what I can tell you, as a point of comparison, is that an induction motor (typically 85 to 90% efficient) can consume it's cost in electricity in as little as 2 weeks. At least that's what I've read. I expect that assumes 24/7 operation, which is not uncommon in industrial settings, and reflects how cheap induction motors are. But it does illustrate how the power consumption can add up under heavy use, especially when dealing with 2 to 3hp motors.

One other consideration is the speed. If you do expect to be in a production mode, and going with servos saves you, say, 1 hour day, then they could pay for themselves fairly quickly. For example, assuming 200 days per year of operation at a "machine rate" of, say, $20/hr, the savings would be $4000 the first year. I don't know how realistic those values are (depends again on your situation) but it does illustrate another potential payback servos might provide.

Anyway, more food for thought! :) I'll be interested in hearing how the Mikini works out for you which ever way you go.

howecnc
08-26-2010, 05:51 PM
When I say a better surface finish, I believe the stepper motor don't hold the same resolution that the servos do.
I don't know that for a fact buy I have run many machines with servos and two machines with steppers and I believe the 3d surfacing and g2/g3 interpolation is better with servos.

SWATH
08-26-2010, 08:21 PM
When I say a better surface finish, I believe the stepper motor don't hold the same resolution that the servos do.
I don't know that for a fact buy I have run many machines with servos and two machines with steppers and I believe the 3d surfacing and g2/g3 interpolation is better with servos.

I see, that makes sense.

mcphill
08-28-2010, 01:53 PM
FYI, you can also upgrade to servos later, if you find you need them, and after you "outgrow" your steppers. By that time, you should be making enough income from the machine to pay for the upgrade, and can also sell the used steppers and controllers to offset some of the cost...

roberto123
09-10-2010, 09:24 PM
Hello, I have a problem with my mikini 1610L...
The spindle stops during the machining...
You can check my post.
I would like to make a troubleshooting guide and also, finally.... the machine is terrible difficult to dissasemble (I mean the sheet metal enclosure) and difficult to clean behind Y axis stepper, don't you think?

roberto123
09-10-2010, 09:25 PM
My blog: http://www.cnczone.com/forums/blog.php?b=947[/url]

shvanbc
04-13-2011, 04:47 PM
Hi Howecnc,

I am currently trying to decide on the PCNC 1100 or 1610L. I have no CNC experience so I apologize in advance if these questions seem very basic.

My sense is that you prefer the 1610L due to better precision, power, speed, etc. Is the difference in precision noticeable in real life or is it more of a theoretical advantage?

From the perspective of a complete CNC novice, would you recommend one machine or the other? You mentioned that programming the Tormach was a little easier - is that going to be impactful for someone who is learning from the ground up?

You said that if the 770 had been released at the time you would have purchased it instead of the Mikini. Can you elaborate on that? It seems to me that the 770 is going in the other direction (smaller machine).

As well, I understand the initial setup of the Mikini is very simple whereas Tormach has indicated to me that it will take 1-2 days to setup the 1100. Is this accurate?

Thanks,

Steve

howecnc
04-15-2011, 08:28 AM
I don't have a real preference in machine. Both have advantages over the other. Programming the machines is identical. Setting up the Tormach for a job is easier because of the TTS tool system.

The 770 has a 10000rpm spindle which would have been better for my situation. I do a lot of 3d surfacing with small ball mills.

The Mikini was setup in a half hour after unpacking it from the crate. The Tormach was setup in 4 to 6 hours after unpacking if I remember correctly. It has been 3 years now since I bought it.

dirtridn2010
04-16-2011, 01:22 AM
Hi Guys. i was thinking of the Servo direction when I was in the early stages of purchase. I had a few emails back and forth with Phil (Mikini) (and others) and he also said that if I wanted servos they would be $1000.00/axis or $1450.00/ axis as a retro fit. At the same time Phil recommended the high speed spindle which has (if I remember correctly) runs from 7000-24000RPM and is water cooled. One of the things I said back to Phil is that I felt that most of my work would be better off with lower RPM (under 7000RPM). Also too, power of the spindle is the same as the standard. which in real terms means that you will have less power when cutting. Because you will use more of your power in maintaining your RPM (the the higher your RPM the more power you consume). Another point is that while servos have twice the power rating they actually have less power at lower RPM (that's Servo RPM, not spindle) than Steppers on the Mikini. Phils advice (which I took) was if you don't think that you will use the higher RPM then DON'T get servos. You would, I expect be able to rapid around a but quicker, But you will have less drive thru your servos when cutting. And lets face it the distance you rapid won't be all that much. Peter

ROCKYMTN
04-18-2011, 05:27 PM
I had no CNC experience either when ordering my 1610L. I was also down to making a decision between the Mikini or one of the Tormach machines.

I ultimately needed the precision that only the Mikini could deliver so I went that route and I'm been extremely happy with my choice. Mach 3 was the biggest issue on the learning curve but I was cutting accurate parts within a few days of setting up the machine.

Phil at Mikini has been beyond impressive with technical support and customer service. Even answering emails on Sunday nights !

I'm an engineer and I can say I'm very impressed with the engineering of the machine, build quality is there, substantial ribbed cast iron everywhere. This thing is HEAVY as another buyer reported - I would say it's around 2200+ pounds. I liked the fact that it was in ONE piece - I don't have that much space in my shop so trying to wiggle in a crane to setup the Tormach would have been impossible.

Cheers from Colorado!

shvanbc
04-21-2011, 02:14 PM
How well does the coolant system work? Does it leak much or give you trouble in any other way?

Steve

ROCKYMTN
04-21-2011, 05:29 PM
For me the coolant system works great. It throws out a LOT of fluid - I was surprised at how large the pump is. No skimpy motor here.

No leaks or issues. Of course, I like the enclosed machining area ! That's another feature which drew me to this machine.

mcphill
04-22-2011, 01:58 PM
Can you post a photo of the bottom of your front door? My door is full plexi, and is "bowed" slightly. When it is closed, the rubber seal has a gap. This gap lets coolant run down the door and surface tension lets it cling under the door and I get leaks down the front. I know the original machine had a metal door with windows - is that what you have?

I have a piece of plastic taped to the inside of the door now to "cover the gap", but tape doesn't like to stay sticked due to all the coolant. Trying to come up with a good final solution. I think I will bolt a piece of angle aluminum to the inside of the door....

ROCKYMTN
04-22-2011, 09:28 PM
Mine has the full plexi too - although it is slightly bowed inward which I can see helps. I did some experiments by aiming both nozzles so they splash off of the vise and up towards the door. I did see some leakage then.

I think you are right about placing a small aluminum angle piece on the inside as that should help. Good idea. I was also thinking about placing a thin piece of plexi or polycarb on the inside to act as a sacrificial protector for the door and maybe I'll add a drip edge on that. Has anybody had their door beaten up by flying chips?

ROCKYMTN
04-23-2011, 01:06 PM
Update - There is a U channel located on the inside of the machine where the bottom part of door meets the rubber gasket. There are drain holes in that U channel and some of mine were plugged with fine swarf. I lifted up the rubber gasket and cleaned the holes. Now fluid runs easily out of the channel - I can now aim both nozzles straight at the door and it drains fine. I also noticed my fluid was foaming slightly and that could cause draining issues so I diluted it some.

mcphill
04-23-2011, 03:12 PM
Ah... My door is bowed out, so it doesn't seal in the middle. Any drain holes get swamped with fluid even with just spash from machining... I'll work on that brace this weekend.

Brian L
04-23-2011, 10:52 PM
Hot air gun and warm up the plexi and put a little bow the opposite way in it? That way it would seal in the middle firmly as you latch it shut?

mcphill
04-24-2011, 10:50 AM
I'll give that a try as well, thanks for the suggestion!

mcphill
04-27-2011, 03:19 PM
Heat did not work. Here's what I did for a solution:

http://www.cnczone.com/forums/mikinimech/127181-finally_fixed_my_door_leak.html