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slowtwitch
09-02-2011, 08:16 PM
It was suggested that i start my own thread on the issues I'm having with the mikini mill. So here it is :)

Let start off by saying that the Mikini is a wonderful machine.. Phil at Mikini does all he can to help you out. But, they really have to stop the blame game and admit that they are having issues. I just received an email from Phil and he was kinda upset. Stating that I am ungrateful for the repairs they did on my boards, at no cost to me.

I would have been glad to have paid for everything, if they would have listened to me from the beginning and repair the boards from the get go. Instead, I was told to buy a motor, sensor ring, get an electrician to check my wiring, buy an EPD, etc etc.

I sent Phil the link of the motor running with the bad bearing. His response was that bearing was good and would last 5000 hours. He also stated the the pulley was damaged when i removed it previously. He also mentioned that my temporary test setup was dangerous and that only qualified personnel should work on the high DC voltages created by the drive. Let me say this, I've rewound small motors and I've rewound very large motors. I've tested motors that ran on 110 volts and I have tested motors that ran on 13k volts. Ground test on 13kv motors required 40 kv of DC..you can smell the ozone being created. So don't tell this old man about testing motors :)

His email was about a page long and not once did he say, "pete we goofed...sorry" or take responsibility. Everything was my fault...I was chastised about my planned AC/vector drive setup. Everything was my fault...

Anyway, I'm done with playing the blame game, you just can't convince some people. It's time to move on. I like this machine and there are a bunch of folks out there that have them. Hopefully my future posts will be of value to someone and they can repair or improve their mill.

Lastly, I have installed a new bearing on the spindle motor. No ball-peen was used in the installation of the pulley..lol

here's a video...

DSCN3764 - YouTube

take care

pete

howecnc
09-09-2011, 05:20 PM
It seems to me that the company did not do enough field testing on the machines before they started to sell them. I have had my ups and downs with mine and consider it my second choice to my Tormach.

GF12
09-14-2011, 04:50 AM
The specs of the Mikini Machines look very nice, but from all the problems people seem to be having I'm wondering if the machine is a reliable product. Does anyone know how many machines are out there that run routinely without problems? Has Mikini sold more than a hand full of machines which are having the problems, or are there many out there that perform great?

howecnc
09-14-2011, 08:21 PM
Mikini does not disclose those numbers, names or any of that information.

Brian L
09-17-2011, 07:27 PM
Serial numbers of the machines should give you a clue.... pretty easy to see who's got what number then and get a rough idea on total quantity.

slowtwitch
09-17-2011, 07:33 PM
Hello, I haven't really done anything with my mill since Mikini returned my parts. I do start it every day to see if it starts and it still does :)

A bit off topic, I have been on vacation for the past week and dedicated my time off to learning G code and learning the inner workings of using Mach turn on my EMCO lathe. The average day was about 16 hrs of researching and learning code. On top of that figuring out how Mach 3 works.

I posted a video of the EMCO cutting some aluminum here.....

http://www.cnczone.com/forums/vertical_mill_lathe_project_log/125045-emco_120p_rebuild.html

pete

aussiedude
10-13-2011, 04:20 AM
I'm fascinated that i finally find out I'm not the only one having problems with my $12k paperweight.
in the almost 2 years i have had it I have yet to cut a complete part.
Its always been because of "grounding, power issues", (i was originally running it on a very expensive diesel generator) but after changing 3 control boards before one worked and finally having a chance to run it on 220v house power, and not to this day getting the spindle motor to stay at speed and not crash i can honestly say it simply isn't reliable.

cheetahcnc
10-13-2011, 08:35 PM
It is interesting that there aren't dozens of positive responses to combat your thread, this may be the answer you seek. I have purchased many machines over the years, some for my employers, some for myself. Very, very few have been trouble free - 100%. I believe a good machine purchase is one that is 90% complete. I have seen over $1 million spent on a system, and it still not be 100%, and I built a system that out performed it for about $250k less. My first personal CNC router purchase cost $16k, and was not able to cut a part, even as the installation tech left with the balance due. It became my hands-on CNC lesson, no instructor included. Classes, if they were available, would have easily cost plenty more than my initial investment. This route, pun intended, was much more challenging and interesting. Plenty of people want to know CNC, they then get their wish - an opportunity to learn it. Believe me, it is a rewarding process. It is good to see you pursue a direction of success, rather than repeat a path of failure. :cheers:

slowtwitch
10-14-2011, 07:33 AM
It is good to see you pursue a direction of success, rather than repeat a path of failure. :cheers:

Thanks for the reply :) My mill is working somewhat since the parts were returned to me. I'm currently investigating a couple spindle options, in preparation for a spindle failure. Which i believe will happen.

Finding a spindle motor was looking kinda of tough, until I saw this....

hossmachine's Channel - YouTube (http://www.youtube.com/user/hossmachine#p/u/24/xSnW0lfmKpc)

If you look at Hoss's other video's, you will find one with this motor in action. He does a 1" deep cut with a 1/2" rougher. I can tell you now that my 3 hp spindle will go into alarm doing this.

Another improvement that I will be looking into are the stepper motors and drives. I may want to play and learn about servo motors :) If I stay with steppers, i will switch to Keling digital stepper drives and motors. I have them on my lathe and they appear to run a lot smoother and quieter. Also with this change will come some type of rpm sensor in the spindle, so that Mach3 can see the actual rpm.

The beauty of all these changes is the knowledge gained by making these upgrades. Everything you need to know can be found on these forums and the web :)

pete

SWATH
10-14-2011, 12:48 PM
Do you thing the spindle motor itself is a problem or the controller board? I agree mine seemed way too eager to go into spindle halt alarm although that could have been due to the spindle RPM dropping. I remember I was doing a conservative cut calculated in Gwizard. While it was cutting it didn't sound bogged down at all and the spindle load meter was barely registering. Then suddenly the spindle just stopped mid cut and the alarm went on, which is an absolute pain in the ass since you have to power down the computer right in the middle of a program then power down the machine just to turn off that blasted sound. In another instance I calculated a cut in Gwizard that required something tiny like .11 HP but the spindle load meter was registering about 50%. I thought that had more to do with the MCU chip on the board fluttering in and out but I was pretty confused as to why the spindle seemed to have no power to make even a conservative cut. I was hoping these were all problems with the board. Sometimes I see videos of the Tormach making a cut and think "that's weird I'm pretty sure that cut on my machine would stall the spindle". What further problems are you experiencing?

Keep us updated on what you do Pete! We need a resident Hossmachine or saunixcomp here on this forum.

slowtwitch
10-14-2011, 04:39 PM
[QUOTE=SWATH;1007417]"Do you thing the spindle motor itself is a problem or the controller board?"

I have to say it's the spindle control board, it just can't take the load.


"Sometimes I see videos of the Tormach making a cut and think "that's weird I'm pretty sure that cut on my machine would stall the spindle"".

And the Tormach uses a 1.5HP AC motor with a vector drive.


"What further problems are you experiencing?"

My display panel seems to have a solder joint. It fades in and out at times. I have to give the screen a tap to bring it back on. Sometimes when it fades , it sets off the emergency button in Mach3. Then I have to reset everything, kinda of a pain.

This was the panel that Mikini replaced :(

Keep us updated on what you do Pete! We need a resident Hossmachine or saunixcomp here on this forum.

I will keep you posted, but, to be put into the same league as those two guys...I don't know. they're kinda like legends :)

pete

mcphill
10-15-2011, 02:15 PM
Sounds like your PC is on machine power? If so, try to sourcs AC to the PC from a constand AC source. I can power down the Mikini and keep the PC onN so I can reset a spindle fault without rebooting the PC. I have only done it once so far, but like you it was during what should have been a weak cut - I think it was a rapid peck drill. I channged it to a standard peck, and it runs OK.

cheetahcnc
10-15-2011, 08:10 PM
In another instance I calculated a cut in Gwizard that required something tiny like .11 HP but the spindle load meter was registering about 50%.

Some things to keep in mind with spindle speed, hp, and vfd's. If a 1hp spindle motor is rated for 3600 rpm, and your output speed is geared down (via pulley or gears) 3:1 to 1200, your torque is tripled to 3hp - not taking into account the losses in transmission. This extra hp is usually required when taking slower, heavier cuts. If you take the same 1hp, 3600 rpm motor and reduce it to 1200 rpm via the vfd, the effective output is still 1hp (in a continuous torque vfd - in a variable torque vfd the output hp is actually reduced). If the same 1hp 3600 rpm motor is over-driven 1:2, to 7200rpm via pulleys or gears, the output hp is reduced to 1/2hp. With the vfd the output is a similar reduction, eg. 3600rpm 60hz motor is driven at 120hz to achieve the speed doubling, the horsepower loss is generally linear. This is basic information, as I am not exactly familiar with your current spindle/motor/pulley arrangement. In some direct spindle motors, when you reduce speed, torque is reduced on a linear scale, eg. 1/2 rated speed = 1/2 rated hp.

SCzEngrgGroup
10-18-2011, 08:24 PM
Some things to keep in mind with spindle speed, hp, and vfd's. If a 1hp spindle motor is rated for 3600 rpm, and your output speed is geared down (via pulley or gears) 3:1 to 1200, your torque is tripled to 3hp - not taking into account the losses in transmission. This extra hp is usually required when taking slower, heavier cuts. If you take the same 1hp, 3600 rpm motor and reduce it to 1200 rpm via the vfd, the effective output is still 1hp (in a continuous torque vfd - in a variable torque vfd the output hp is actually reduced). If the same 1hp 3600 rpm motor is over-driven 1:2, to 7200rpm via pulleys or gears, the output hp is reduced to 1/2hp. With the vfd the output is a similar reduction, eg. 3600rpm 60hz motor is driven at 120hz to achieve the speed doubling, the horsepower loss is generally linear. This is basic information, as I am not exactly familiar with your current spindle/motor/pulley arrangement. In some direct spindle motors, when you reduce speed, torque is reduced on a linear scale, eg. 1/2 rated speed = 1/2 rated hp.

You're confusing torque and HP. Gearing changes torque and RPM, NOT horsepower.

HP = Torque * RPM / 5252 with Torque measured in Ft-Lbs.

Or, conversely

Torque = HP * 5252 / RPM

Gearing will increase torque, while reducing RPM by the same ratio, or vice-versa, so HP is constant, regardless of the gear ratio.

A 1HP/3600RPM motor will deliver 1.45 Ft-Lbs of torque at 3600 RPM. Gear it down 3:1 and torque is increased to 4.35 Ft-Lbs, while RPM is reduced to 1200 RPM. The output of the reducer is still the same 1HP the motor is putting out. Gear it up 1:3, and torque is reduced to 0.48 Ft-Lbs, while RPM is increased to 10800 RPM. The output of the reducer remains the same 1HP.

Regards,
Ray L.

cheetahcnc
10-21-2011, 03:07 PM
I agree horsepower is a function of torque and time. To simplify motor selection, using HP is easier. If you require 1hp for a given cut/task (as many machining functions are given in HP, not torque), and you require 2x the name plate rpm via gears, pulleys, vfd, etc., you need to start with a 2hp motor. This will give you the equivalent of a 1hp motor at the spindle, or 1hp worth of torque at the spindle. Then we could reduce the number more by factoring in diameter of the cutter, as torque/hp ratings are given at the center of the motor shaft. Figure it out any way you like, it would need the bigger motor.

rowbare
10-21-2011, 03:46 PM
You are changing the laws of physics.

HP is a function of torque and speed not time. It is a measure of power i.e. how much work can be done in a given time. In our case, it is normally rated in how many cubic inches of metal can be removed in a minute. You can find tables listing the Metal Removal Rate for various metals expressed in cubic inches per minute per HP. A 1 HP 1000 rpm motor will remove as much metal as a 1 HP 5000 rpm motor. However the conditions under which it will do so are different.

Changing speed via mechanical reduction is very different than changing speed with a VFD. When changing speed mechanically, the motor stays at its rated speed and will therefore will put out its rated power (minor mechanical losses aside) at all speeds. The metal removal rate remains the same since the power is the same.

Now using a VFD is a different story. An AC motor under VFD control can be treated as a constant torque device under its rated speed and a constant power device above. Thus if you run a 3450 rpm 1HP motor at 1725 rpm, it will be putting out 1/2 HP. Run it at 4500 rpm and it will put out 1HP albeit at reduced torque. At half speed, it can remove half as much metal as it can at its rated speed or higher.

bob

cheetahcnc
10-21-2011, 09:00 PM
...Thus if you run a 3450 rpm 1HP motor at 1725 rpm, it will be putting out 1/2 HP...

bob

This is similar to my original post description, what happened to all your torque specs?

slowtwitch
10-22-2011, 01:38 PM
Here's a little update on my mill. I have been having a problem with my front panel. With the machine running and when a load is put on the spindle, the panel would lose all the graphics.

It would still run under manual, but under Mach, it would go into emergency stop at times. I would then have to give the screen a tap and the screen reappears. Then i would have to reset everthing, etc, etc, etc.

This kinda lead me to believe a loose connection of some sorts was the cause. I have rewired the entire machine and installed all new connector ends. These connector ends are polarized, unlike the Mikini ones that are not. I double checked everything and all looked and tested good.

Then I suspected a bad solder connection. I narrowed down the area that I suspected was the culprit. If you ever had the panel off, you have a board where all the connections are made, your parallel port, relay board, drivers, etc. and then there is another board underneath the connection board. I would have to say it's the main board. This was the board giving me problems.

When i removed the top board, i could see right away the some type of repair was attempted. There was a lot of solder paste all over the board. It looked like they attempted to do a "Re flow" repair. Because these boards have surface mounted components (SMD), re-flow soldering is a common repair tactic.

Anyway, they didn't succeed.

I don't really want to deal with Mikini again, so I decided to make an attempt at the repair myself. I searched the web and found a ton of stuff on re-flow soldering, especially hot air soldering. I had some soldering paste from my Megasquirt engine mcu project. I spread it over the solder in an area that i believed to be the problem area (very little is needed). I brought out my industrial strength heat gun and proceeded to heat up the area. I could see the paste begin to react and shortly afterwards stopped heating the area. I admit, i was kinda of nervous about the whole thing...it is kinda of spooky :)

Once things cooled down, I cleaned up the board and used some "air in a can" to get in every nook and cranny to clean things up.

Now came the moment of truth, hooking everything back up and see if I made a bad decision or not.........


IT WORKED !!!! It's been a week and a half, I have made some deep cuts with repectable feeds, crashed a couple of times stalling the spindle and the screen has not faded out on me yet :)

Now I just have to learn this g code stuff and stop crashing into things..lol

Oh, one last thing. I'm thinking of starting a new thread not bashing Mikini mills, but, on how can we improve them ourselfs. These are really great machines mechanically, they just need some help in other area's.

One of the things I'm looking into right now, is having the ability of Mach3 seeing the actual rpm from the spindle. I think it's very doable...we'll see :)


pete

mcphill
10-22-2011, 06:02 PM
Enabling RPM feedback is very easy, all it takes is a digital input to MACH3. I added one to my router a while back and plan to do the same on the Mikini. I also have been buying some parts to do either a semi-auto drawbar, or a full auto one (or start semi and go full auto).

Also, I just got a set of Tormach TTS tools, and was disappointed to find out that the surface of the Mikini is too far from the face of the R8 collet (or the camfer of the collet is too shallow - same difference). So I need to add a ship to the face of the Mikini spindle. Not ideal, but not the end of the world. The face of the Mikini is VERY flat and planar to the bed - I was afraid it would not be, but was happily surprised!

Down the road, I will start with a winerack tool holder, and am thinking about upgrading it with the Tormach automatic toolchanger as well.

So many ideas, so little time!

Brian L
10-22-2011, 06:23 PM
Not sure if I understand you correctly, but the TTS system requires a modified 3/4" collet, it has to be ground short on the nose so that it doesn't protrude. That way the ring of the TTS holders hit the spindle nose.

mcphill
10-22-2011, 07:03 PM
I bought the TTS from Tormach. When it is in the Mikini, and a TTS tool is tightened in to it, there is still a gap between the TTS tool and the face of the spindle. I need to add a shim to the face of the spindle in order for the TTS to make contact with it.

Brian L
10-22-2011, 07:09 PM
Let the holder hang down a bit and tighten the collet, see if the flat fronted 3/4" collet is still sticking out.... if it is and that's why your holder won't go all the way in, then grind the face of the collet back further. Then your tool holder will hit the spindle nose.

You don't want to have to mess with a washer on each tool, you did the TTS to make things faster and more consistent....

SCzEngrgGroup
10-23-2011, 09:42 AM
I agree horsepower is a function of torque and time. To simplify motor selection, using HP is easier. If you require 1hp for a given cut/task (as many machining functions are given in HP, not torque), and you require 2x the name plate rpm via gears, pulleys, vfd, etc., you need to start with a 2hp motor. This will give you the equivalent of a 1hp motor at the spindle, or 1hp worth of torque at the spindle. Then we could reduce the number more by factoring in diameter of the cutter, as torque/hp ratings are given at the center of the motor shaft. Figure it out any way you like, it would need the bigger motor.

"horsepower is a function of torque and time" - NO. HP is a function of Torque and RPM. Time has nothing to do with it.

"If you require 1hp for a given cut/task (as many machining functions are given in HP, not torque), and you require 2x the name plate rpm via gears, pulleys, vfd, etc., you need to start with a 2hp motor." - No, that is simply not true. If the motor is rated for 2HP, then you get 2HP AT THE SPINDLE, no matter whether you've geared it up or down through gears, belts, pulleys or any other mechanical means. A VFD will affect torque, as VFDs (until you reduce the speed a lot) are typically constant torque up to the motors rated speed, and constant HP above that speed. So if you use a VFD on a 1HP motor to double the spindle speed to 2X the motors base speed, you STILL get only 1HP at the spindle, just at a higher speed. Torque at that higher speed will be 1/2 what it is at the motors base speed. Again, HP = Torque * RPM / 5252. There is no other way to calculate HP.

"Then we could reduce the number more by factoring in diameter of the cutter, as torque/hp ratings are given at the center of the motor shaft." - The cutter diameter has nothing to do with either torque or HP, and torque and HP measurements and ratings have nothing whatsoever to do with cutter diameter, nor is either "given at the center of the motor shaft". Torque and HP are exactly the same, whether you're using a 1/16" endmill, or a 4" facemill. What DOES change with tool diameter is the amount of FORCE that can be applied at the cutting edge of the tool. A 1HP motor driving a spindle through gears or belts at 3500 RPM will be able to do 1HP of work AT THE TOOL. That will represent a torque, at the spindle, of 1 * 5252 / 3500, or 1.5 ft-lbs. If you use a 1" tool, the force at the cutting edge will be 1.5 / (1/12), or 18 pounds. If you now switch to a 4" face mill, the torque remains 1.5 ft-lbs, but the force at the cutting edge is reduced to 1.5 / (4/12), or 4.5 pounds, due to the longer lever arm created by the larger tool. HP is the same, 1HP, in BOTH cases.

Regards,
Ray L.

mcphill
10-23-2011, 11:18 AM
That's the problem, the collet is sticking WAY out (like about 1/8"). Taking the face off of the collet is probably a better answer - guess I will face it off with a lathe tool. I was thinking of putting the spacer on the face of the spindle though, not in each tool (that would be a PITA!).

MichaelHenry
10-23-2011, 04:18 PM
Phil - you can buy a 3/4" R-8 collet from Tormach that is designed for the TTS system for $22 and they probably have them in stock so you are just a day or two away from having one. Or grind the face of your existing collet down yourself.

Mike

mcphill
10-23-2011, 05:51 PM
As stated above, this R8 collet IS from Tormach, directly! It states in their manual that there can be two ways it might not work, and on my Mikini, the case is the first one they highlight. If you care to see, it is the photo next to section 2.2 in the manual here: http://www.tormach.com/uploads/42/31866_TTS_Manual-pdf.html

I know how to fix the problem. I was just reporting what I found in case someone else was looking to combine TTS with their Mikini (and see if anyone else has the same "issue" on their Mikini). Guess I should post my own thread and put up some pix, etc., but I am finally home for a few days and would rather watch football and veg on the couch!

Happy Chip Making!

SWATH
10-24-2011, 03:37 PM
Pete,
You said you were running on raw power now and not using the transformer. What is your voltage now? I'm just debating on powering my machine or not, the adjusted voltage is now around 246-247V which is within spec but pretty close. I also got to thinking, what is the voltage on the two legs going into your axial power supply board? I was getting something like 60v and 6v or similar and thought how can high voltage (over 250V) damage something that is powered by the toroidal transformer at a much lower voltage.

MichaelHenry
10-24-2011, 03:39 PM
As stated above, this R8 collet IS from Tormach, directly!

Sorry, missed that fact in the earlier post. Hope the fix works out well for you.

Mike

slowtwitch
10-24-2011, 05:39 PM
Pete,
You said you were running on raw power now and not using the transformer. What is your voltage now? I'm just debating on powering my machine or not, the adjusted voltage is now around 246-247V which is within spec but pretty close. I also got to thinking, what is the voltage on the two legs going into your axial power supply board? I was getting something like 60v and 6v or similar and thought how can high voltage (over 250V) damage something that is powered by the toroidal transformer at a much lower voltage.

Swath, When I had the parts being repaired, I was getting about 237 volts across the line. Today I am getting 252 volts and 58 volts across the transformer..go figure. I'll give it another try tomorrow with a different meter. But, in my mind, it shouldn't matter. These are hobby mills..sorry Phil, and they should be plug and play. To think that you should have to monitor your voltage before use is insane.

Anyway, the mill is still running and it's running better since I did the re-flow on the main board..... I cut my first piece without any shut downs or faults.

I personally don't think you have any issues with your voltages. Hook up a computer to your mill line ( they can run on 120 or 220)... I'll bet that it won't burn up and it uses the same type of "delicate components" as your mill.

Did you get the EPD, if so has it tripped??? You mentioned before about using a GFI, did that tripped ??? If the answers are no , then ground faults are not an issue.

You have a bad board or BLDC driver or both, just like i did. They should replace your boards with brand new ones. I'm very leery of repairs made by them. They're bench skills, of which I saw, are very suspect.

pete

SWATH
10-25-2011, 01:50 AM
HA! 252V and it runs fine. It seems the new board fixed my problems too, check out my thread. My voltage is 247V and the axial supply legs add up to 56V. BTW the 5mA breaker has never tripped (except for when I press the test button or short it out).

allenj20
10-31-2011, 11:43 PM
Hey Phil, I use TTS with my Mikini and I ground my own collet from a Lyndex 3/4 inch collet. The TTS one which I also bought does not fit in mine either the spindle taper is too tight it is not within spec. Phil will feed you some line about new collets being oversized so they fit better in clapped out Bridgeports :bs:. But the reality is the R8 taper in the Mikini is some Chinese interpretation of the spec at least on mine.

At any rate I started with a Lyndex collet which is still too tight but fits a bit better and ground the face flat on a disk sander. It does not have to be super level because the tts holder does not rest on that face.

good luck


As stated above, this R8 collet IS from Tormach, directly! It states in their manual that there can be two ways it might not work, and on my Mikini, the case is the first one they highlight. If you care to see, it is the photo next to section 2.2 in the manual here: http://www.tormach.com/uploads/42/31866_TTS_Manual-pdf.html

I know how to fix the problem. I was just reporting what I found in case someone else was looking to combine TTS with their Mikini (and see if anyone else has the same "issue" on their Mikini). Guess I should post my own thread and put up some pix, etc., but I am finally home for a few days and would rather watch football and veg on the couch!

Happy Chip Making!

mcphill
11-01-2011, 10:59 AM
Funny. I had another larger collet, and neither it nor the TTS one I bought would fit in the spindle. The pin that goes in to the keyway on the collet extends out too far (must be that interpretation thing). I actually tapped the collet in to force the pin back some. On another collet, I was grinding down the keyway so it would clear, but I never got it to fit. I decided to say F-it and hammer on it to make it fit. Probably not the best idea on a "fine piece of equipment", but what the heck, it fit in the end. Still need to turn the face of the TTS down though, maybe today...

allenj20
11-01-2011, 11:07 AM
Collets are hardened so I don't think it will turn easy which is why I ground it.

Cheers, Allen

mcphill
11-01-2011, 01:59 PM
Worked fine with my insert tool. Being updated here:

http://www.cnczone.com/forums/mikinimech/139489-using_mikini_tips_tricks_wanted-post1015399.html#post1015399

SCzEngrgGroup
11-01-2011, 05:45 PM
This is all so disappointing.... I was really excited when I first came across the Mikini about a year ago, and really wanted to buy one. Even more so when I realized their headquarters is just a short distance from my house! But with all the problems I'm seeing with the spindle drive, and now seeing that the R8 taper is clearly out of spec, it's looking a WHOLE lot less attractive, and the Tormach is starting to look at lot better.

Regards,
Ray L.

MichaelHenry
11-01-2011, 06:19 PM
Looks like there is a Tormach demo location in San Carlos and a local referral in San Jose - are either of them close to you?

Mike

SWATH
11-01-2011, 08:21 PM
This is all so disappointing.... I was really excited when I first came across the Mikini about a year ago, and really wanted to buy one. Even more so when I realized their headquarters is just a short distance from my house! But with all the problems I'm seeing with the spindle drive, and now seeing that the R8 taper is clearly out of spec, it's looking a WHOLE lot less attractive, and the Tormach is starting to look at lot better.

Regards,
Ray L.

As a Mikini owner for almost a year and without one thing made on it I will say run like the wind. Go get that Tormach and don't look back. I wish I could say this machine is awesome (and it is in many ways but not where is counts) but I can't. The electronics absolutely stink, specifically the spindle board. If the damn spindle would work reliably then I would say that this thing is incredible but since the spindle is kind of important it kind of puts a damper on everything. Also from what I know about Tormach is that they will bend over backwards to make sure you are up and running. When you have a Mikini problem they are kind of like "what have you done to screw up our perfect machine" They are nice and all but their replies are typically deflection and obfuscation filled with techno-babble which you have no way of refuting. I don't believe for a second that this is some industrial class machine, anyone trying to make a living with this thing is going to lose their shirt not if but when it doesn't function properly. When I got a new spindle board after the defective one I had been trying to putz around with for 7 months crapped out I told them that the new one was working fine with no dips in rpm, their reply was to the effect of "sounds like you got your power supply issues worked out". My voltage is the same and has not changed other than me insisting the power company replace a capacitor that was bad which has not changed my power a wink.

I'm just a little heated right now and frustrated because my spindle motor still seems to be acting funny with the timing, not getting to max rpm, having a high spindle load when cutting air, stalling out on weak cuts, and now the spindle itself gets very very hot in no time, something I've never noticed before, must be a new problem. Then to be informed that I may be damaging the electronics with my tuning procedure. If there were more documentation other than the CYA booklet passed off as a manual maybe I would know what not to do. Anyway I'm about 2 seconds from selling this headache and getting something else. Don't listen too closely to me though, I've noticed I've become bi-polar with this machine. When I think it's working, it's the greatest thing in the world. When I find a problem that affects the function that I can't fix easily I'm about ready to back it off a cliff. Right now I'm mad but if miraculously it started working right tomorrow I would be singing glory from on high.

If we could just spec out an aftermarket spindle board and perhaps motor that is a direct plug and play replacement I would buy it in a nano second. Unfortunately I don't know enough about it to do so, which is why I bought a brand new machine under warranty...


Oh BTW my R8 taper spindle was also very tight and still does not fit some of my Maritool collet chucks (I think the index pin is too long). In fact when I got the machine it came with 2 ER25 collet chucks which would not fit in the spindle. Turns out there was a bunch of what appeared to be welding slag or something caked on the inside, which I had to chip out with a screw driver, took about 2 hours total I guess (most of it was way up there in the shaft portion). They fit now but are very tight.

SCzEngrgGroup
11-01-2011, 08:30 PM
Looks like there is a Tormach demo location in San Carlos and a local referral in San Jose - are either of them close to you?

Mike

Mike,

That's not too far - I'm just over the hill in Santa Cruz, and have to go over that way fairly often.

Regards,
Ray L.

chipmiser
11-02-2011, 12:58 AM
Thank you swath, it is a relief to know there are others riding the mikini roller coaster.
By the way, I asked mikini support if there were any rev changes on the controller. Believe it or not, there is a controller in testing and has a planned releases in another year or so. Interesting,,,,

SWATH
11-02-2011, 01:10 AM
Thank you swath, it is a relief to know there are others riding the mikini roller coaster.
By the way, I asked mikini support if there were any rev changes on the controller. Believe it or not, there is a controller in testing and has a planned releases in another year or so. Interesting,,,,

That's good news I guess, but a year or so out? That's depressing but at least we will have plenty of time to test our ground lines, obtain some dilithium crystal to power it, and get our phDs in electrical engineering to turn it on. I'm sure they will not recall the current ones and I guarantee they will cost us in excess of $1000 to get one but they have also been saying the 1610LP would be out years ago.

Just curious what all was discussed regarding the controller board? Do they concede that there is a problem with the current one?

MichaelHenry
11-04-2011, 06:56 PM
Mike,

That's not too far - I'm just over the hill in Santa Cruz, and have to go over that way fairly often.

Regards,
Ray L.

I don't know what the demo location is, maybe LittleMachineShop?

The local referral is probably another owner that is willing to discuss or show his/her mill.