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How to use Ubuntu - Klang Malaysia
Hi,
I would like to take the opportunity to thank Gerald for this excellent forum to share wealth of information he possesses selflessly. Thanks in advance to Gerald and wonderful people here for helping my journey into building a MechMate. I'd been tinkering around with baby scale CNC project using salvage printer motors and diy driver... Plenty of fun but doesn't fulfill my over bloated ego. Then I stumble across this site... and I beat myself for not discovering any earlier. Now, MechMate is the real McCoy,the full-fledge Man-Scale CNC bot to demonstrate my manhood! The key to success is right here in this forum! I am competent with mechanical design, electrical design, milling, lathe, shaping, sheet metal fabrication, welding, oxy-cutting, metal forming, woodworking, soldering. And I'm also the rare ones who works with metrics and imp system on day to day basis. Presently trying to learn physical computing. My Building Plan No fix time frame but more of sequential events 1) Purchase component to build the "Kitchen Table" project. 2) Build the Control Panel/station 3) then the Mechanical part. My spec. Color :- BLUE ![]() Work area :- 1220 x 2440mm (4' x 8') Stepper motor :- 89HS9801 (Deitech Control) Speed reduction : 7.5:1 gearbox (Deitech Control) or 3.2:1 belt reduction Rack :- Module 1 or Module 1.5 pending on forum advise Pinion :- Largely depend on the rack and advise from the forum. Spindle :- Existing Cheap trimmer + DIY PWM speed controller. BOB :- DIY Motor Driver :- DSP Based Microstepping Driver DM558 (Deitech Control) PSU :- switching mode power supply CPU :- DIY, Atom Mobo, 1Mb ram, 8GB pen-drive. or if I can get hold of a free old PC. Dust Management :- Existing shop vac for now Vacuum Hold down :- Wouldn't that be nice.... later Others : Microprocessor control external swithches such as E-stop, limit switches, homing... Future upgrade :- 4th axis, 5th axis, 6th axis.... Money is not a unlimited resource for me, so budget US1500 on all electronics & components. The rest? I'll just have to figure it out... some how... I'm corresponding with Claudia at the moment, need lots of input to help me to make up my mind for the kitchen table project. Please advise on 1) the stepper motor and the microstepping driver 2) the Gearbox 7.5:1 is dirt cheap less the US25 FOB.... should I just buy and talk later 3) I want to try the DSP based driver... it says "servo-like performance on stepper motor"... tempting tempting @US60FOB 4) the rack is also economical... choose module 1 or module 1.5? can't do both as shipping will be too expensive and minimum order is 10 meters each... Just enough, I think... 5) pinion, I can source locally... so no hurry... From then on, there will be no turning back... Cheers Last edited by KenC; Thu 02 July 2009 at 05:27.. |
#2
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Welcome Ken.
Module 1 is the better choice, if you can get it. It is finer, with smaller teeth, for smoother motion. The only negatives about going too fine is if teeth break off (too small for the load), or the pinions jump out, or the teeeth get blocked with dirt. But nobody is reporting these potential factors as real problems. With a small pinion on module 1 you can achieve a higher pulse/millimeter value than with module 1.5. PS. I was in KL in March, and I think I will be there again within a year. |
#3
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Hi Gerald,
Thanks for the speedy respond. Ok one down, Module 1 rack 7.5:1 gearhead (<$25 per piece FOB)or DIY belt reduction or Direct Drive? DSP based driver? The 89HS9801 has almost identical spec as MK's 34HS9801 (notice some similarity about the) model code ![]() ##PS, Great, I'm 20miles off KL... we must meet up! I'll buy you our famous Bah Kut Teh (a local delicacy, herbal pork stew) Last edited by KenC; Thu 02 July 2009 at 06:12.. |
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7.5:1 gearhead (<$25 per piece FOB)or DIY belt reduction or Direct Drive? The gearhead's backlash specs are unknown - stay away unless you are absolutely sure it has low backlash. Start with direct drive and then build belt reduction once you know that everything works.
DSP based driver? What is "DSP"? The 89HS9801 has almost identical spec as MK's 34HS9801 (notice some similarity about the) model code ![]() |
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Hi,
DSP = Digital Signal Processor. I did some search on this subject, what it does here is place a PI algorithm in the signal path to "tame" spiky respond of conventional. The advantage is less noise and smoother movement resulting faster moving rate. See this http://2007.iccas.org/submission/pap...0on%20FPGA.pdf I wonder if anyone here has any experience with DSP based driver, not necessarily of the same brand. a thread at cnczone http://www.cnczone.com/forums/showpo...51&postcount=1 I didn't think of the backlash... thanks for the pointer. So 7.5:1 gear box is out for now. Mentioning 89HS9801 twin spec as 34HS9801 is just for information. So my kitchen table list 89HS9801 w/o gearhead DM556 Atom Mobo c/w 1Mb ram, 8Mb pendrive, no hard disc, no DVD. + parallel card. Power Supply Others I recon it would be safe to conclude Module 1 with 30 teeth. Did I miss anything? Thanks you gerald for the pointers. Cheers Last edited by KenC; Thu 02 July 2009 at 20:15.. |
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Psu
Hi,
The PSU workout the coil L=4.1mH V = 32 Sqrt(4.1) = 64.8V <65V dc Rated current = 4A I = 2/3 * 4A * 4 units = 10.7A Ipeak = 4 * 4A = 16A Did I miss anything? |
#7
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If you are starting without gearhead, reduce the pinion to 24 tooth module 1.
What breakout board are you using? Ipeak = 4 * 4A = 16A will never happen. The measured Ipeak is less than the 2/3 value. |
#8
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Hi,
BOB I'll DIY a BOB, For what I'd learn, the function of BOB or computer interface card is to distribute the correct signal ports to the correct places, provide a passive current protection/.isolation from the external peripherals. I'll need to find out the parallel pinout of Mach3 and/or EMC3, then distribute the signal ports accordingly with current limiting resistor or even better a opto-isolator. That shouldn't be too difficult to etch a single or double sided PCB and solder a couple of sockets and resistor/isolators. Unless I am missing something Rack & pinion Module 1 with 24teeth will be it. I would definitely implement some sort of belt reduction. Its a preference. 1) buffer the stepper motor shaft from unforeseen axis load, 2) increase final pull out torque which lead to better acceleration and deceleration and 3)resolution quality. PSU Ipeak does happen, in transient form i.e. short micro second spikes eg, starting, stopping.... It is very difficult to take notice on a voltmeter. Has anyone had logged a current measurement? But is a need to know for design purpose, I'll use this value to size in-line fuse (if its required), to size the passive component (if any) with it. Operation condition is always 2/3 or 1.5 safety factor of my design. A word of caution, toroidal tranny is less tolerant to over load because of its higher flux efficiency(which is suppose to be its strength). so please do double the VA rating of your tranny. As for EI core tranny, no doubt it is less efficient and has magnetic leaks but it is much more robust and tolerate over load. one can use one with 1.2x of rated VA. It's not really expensive to wind a EI core locally. By the look of the spec.... I don't think a SMPS is economical... ![]() PSU, with EI core the tranny, Sec. winding voltage, 65V + 2(0.7) / 1.414 = 46.96Vac ~47VAC We had I=10.7A VA Rating, VA =65*10.7*1.2=835VA.... ![]() this will be quit a big chunk of iron.... I may consider multiple tranny instead. Power bridge & capacitor are affordable here. Last edited by KenC; Thu 02 July 2009 at 22:25.. |
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The short, transient spikes are higher than the Ipeak you calculated. But you are forgetting that there is a big capacitor between the load and the transformer. Our transformers, measured a couple of times for various motors/applications, experience a load of less than 2/3 of the calculated sum of the nominal peak motor currents. Please trust measurements more than your theoretical calcs.
![]() Generally the support at this forum is for the tried and tested way of building MechMates. If you are using different motors, drives, breakout boards, transformers, then our advice dries up (or gets misleading) and you have to double-check everything yourself. For example, your voltage calc applies to Geckodrives, but you are using something else - that manufacturer may have a different way of calculating voltages. In fact, that drive may even require an AC supply. (I don't open every spec sheet pasted here to check these things). (My comments on Ipeak are again for Geckodrive - your drives may run hotter and need more current) |
#10
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Hi Gerald,
Point taken. I have the tendency to do things the long way... ![]() I like to do thing a little different here and there, in the name of learning and experimenting... From what I find here, the mechanical portion MechMate had been perfected for a rack and pinion system. Elegantly simple and efficient. Everyt single detail had been beaten to death! It is counter productive to reinvent the wheel here. Contrary to that, there are soo much going on in the electronic sceen. eg, servo motor, I stepper motor with the performance of servo motor, PC choice... etc etc... By starting with the Kitchen Table project first, I hope to contribute a minor alternative to the test and proven Gecko system. and mind you, my choice of driver & motor is below US$600~700 for 5 sets all in... If I keep up with scroughing around, the US$1500 budget might just be possible! To me reliability of the electronics parts is not stringent as I don't think I'll run my MechMate as a business. In a way, it has good basis to be a test bed for new ideas. This is my contribution. I would like to clarify that I do not have any affiliation with any commercial entity in anyway. I am a hobbist, working from my own fund. In no way I wish to be stubborn and egoistic. Your help and advise is always relevent and treasured. Cheers |
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Ken, we would very much appreciate some alternative systems being developed, but I don't want you to think we are unhelpful because we don't respond to your questions. And I just wanted to be sure you understand the risk of following advice that somebody might give you, because that person may not realise the differences in your system.
In no way did I for a minute think you are stubborn /egoistic, I appreciate your energy. Thanks. |
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Gerald,
Great! I love your answer ![]() Don't worry about misleading advise... Lets open that as discussion. I'm confident everyone here are rational and capable of competent analysis. Let just put the question on the table and beat it to death. ![]() Now proceed... Just learn that BOB can be very affordable, $20~30.... really tempting... my DIY time is worth more then that ![]() ![]() My Kitchen Table Shopping list 1) 89HS9801 (4pcs) 2) DM 556 DSP-based Driver (4pcs) 3) Module 1 rack, 10 x 1 meter (I know its not needed now but I wish to save some shipping by consolidating shipping) 4) Atom mobo, 1Mb ram, 8Gb pendrive, + PC PSU. 5) BOB Gecko? CNC4PC?...others? 6) PSU parts, Tranny, caps, bridge rectifier. 7) RG59 signal cable. Is the list complete? Cheers |
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When you design your break-out-board, you might consider adding a buffer chip(s) (74ACT245 chips work very well). Parallel ports don't always give TTL voltages or current. The buffer chip(s) will ensure that you have enough signal to drive your stepper drivers. The 74ACT245 chip has eight channels and usually costs about $1 each.
The "ACT" series is capable of sinking or sourcing up to 24mA per pin. Many stepper drivers require 15mA per signal to drive their opto-isolated inputs properly. |
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Mike,
Thanks for the pointer. Now I know why some BOB has a power supply on it... Cheers |
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Hi,
Just purchase the Intel Atom DG945GCLF mobo, c/w 2Mb DDR2 for just under US$100... Now, I'll have to find that old PC power supply unit.... somewhere in my junk pile... ##PS, Its been over 20years since I last build a PC... It's so much easier now a days. |
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Read...Buy... Plunder...
Hi,
A lot had happened in the past few days! Decided to make some changes in career prospective, for the better I hope... YET, the decision to build MM stays intact nevertheless. Will definitely affect build schedule and resource. Reading and more reading... When I'm not reading and making changes to my career:- *Bought ring folder and filing pockets to file up the plan drawings. A necessary decent treatment . *Study the plans,(much easier with hard copies) remove the options... Choices so far 1) MS angle rail 2) 300mm Z-axis (keep mechanical build and troubleshooting simple) 3) proximity switch 4) Direct Drive 5) Grinding jig (a must!) 6) Electrical for 230V c/w all safety. *Continue hunting for new parts and useful junk for recycling. *Found 2 PCs, c/w CRT monitors full size ATX casing. One will house my Atom, the other to house the driver system. *Located lazer cutting service locally, quoting in progress. Need more follow up. *Working on the final details of purchase order for me motors, drivers and rack. Hopefully, to close the deal within this week. The rack will be Module 1 with 24th pinion as advised, for this I'll stay away from the gearhead and belt reduction for the initial build. Some hick-ups/inconclusive decisions #Work Area The minimum order for the rack is 10 meter, more then required for a 1250x2450. Knowing the extra cost for larger working area is negligible, I am seriously considering building as big a working area as the rack quantity allows. Wonder what is the safe maximum work span of the y-axis, Maybe 1830mm? (Y+170 = exactly 2meter rack) then X = 3500mm and I'll have 300mm balance after Z-axis....??? Hate it when I'm spoiled with choice ![]() ![]() ![]() ![]() Maybe I'll just follow the "default" plan dimension 1850 x 2750 mm.... ![]() ![]() #Z-axis Some forum members used screw and linear guide/bearing for Z-axis, got me interested,wonder if there will be cost saving and/or shorter construction time? Hence, more reading required ![]() Hope I did not made any stupid and careless considerations above. Thanks in advance for the advises. Thanks in advance. |
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Think twice about going for a table that is bigger than the boards that you will be cutting. If the boards and table are the same size as each other, it is quite easy to put a couple of g-clamps around the edges.
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Ah....
![]() No more reading on table size 2440 x 1220 is final! Thanks Gerald. What else happened in the past hours.... *Read more on linear motion stuff here... Well... Roller on rail + rack is still the best compromise for my needs, i.e. mostly 2D cuts with some simple 3D cuts. If I want precision, I won't use wood... It will be another story if I already have a set of linear bearings & screws laying around collecting dust... *Went through the plans more thoroughly... Came up with a Bolt & Nut draft B.Q. ... Need to work out the B.Q. for steel once I find my concentration... *The V-wheels from Superbearing US$264 through USPS, w/o insurance, w/o registered... quite dear & risky... & I may end up paying Tax if I'm unlucky... That calls for a visit to local machining shops. *Need to be 100% on the V-tyre material. The V-Tyre M1 20 121 T B stated material "hardenable steel". with 1.6 micron finishing Is it ok to turn S45C or EN19 or any BDMS and not grind, cos I may not find affordable vacuum hardening and grinding service locally. My logic is the rail is SS400, it can hardly wear the wheel. Sand polish the contack surface & running the wheel up & down the rail a couple of hundred time... ![]() Eccentric Bush M1 20 210 T B & wheel axle bolt. Our local bolt & nut shop stocks HTS M12 bolt with precision grind shank, for ~US1. This is ~5X more expensive then a plaint bolt but I think it is a much better implementation and worth the extra. Thousand Thanks!! ##PS, It takes more effort to find fault with Gerald's design... and very likely its as waste of brain juice and time . Thumbs up to MM! |
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Wheels: Lots of different materials have been used for DIY wheels, from hardened/ground steel to hard plastic (and soft steel, cast iron and bronze as well), and we have had zero reports of those wheels wearing out. Looks like you can just about use any material and method?
Bolts: I use HTS (high tensile steel) for everything. Minimum metric grade 8.8. Main reason is that they can be fully tightened by hand without fear of damage. The extra precision offered is not important - we are bolting to a welded frame that has low precision and the bolts will not improve it. |
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Thanks Gerald,
Wheel: What a great relief to know wear isn't an issue! Will bring the bearing to local machine shop for a quick chat. Bolt: OK, use only simple plain HTS bolts. ... No problem... Continue reading..... study the drawings.... Cheers |
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Bought the Motor & driver
Bite the bullet and ordered the motors & drivers today
Shopping blindly can bee addictive and dangerous... To manage this, I made up a draft list. Hope to contain my senseless buying impulse. Parts Shopping list 1) 2-phase Hybrid Stepper Motor _ 4pcs (Import) Ordered 2) Microstepping Driver _ 4pcs (Import) Ordered 3) Module 1.0 Spur Gear Rack _ 8 meter (Local) Located 4) Module 1.0 Spur Gear _ 4 pcs (Local) Located 5) 3M VHB series double sided tape _1 roll (Local) Found source 6) Bearing No.6001.2RSR _ 28 pcs (not started but should be able to find everywhere) 7) Laser Cutting profile (Local) Located 8) Router for Spindle (Local) Existing 9) optional water cooled spindle + VFS (Import) 10) Gas Spring (local comparable?) No idea at all... 11) Spring (Local) Located 12) PC + Monitor (Salvage) Found/received 13) Atom Mobo. Bought 13) Control Console/Panel (Salvage) 14) Electrical (Local) Verious electrical harware shop a) Interlocking Isolation door Latch (optional) b) Contactor, 15 Amp _ 1unit c) Emergency Switch (E-stop), _ 3 pcs d) SMPS ,<50V @>11Amp _ 1 unit e) 4" Fan, 240V _ 4 units f) RCB (isolation switch) _ 1 unit g) Air intake filter _ 1 unit h) Heat sink i) Shielded cables j) Fuse and fuse Holder _2 units k) Push botton switch _3 units L) Relays, 1 unit M) Main Line filter, (DIY CMRR filter 50mm Toroidal core) N) Proximity switch (Optional) Machine shop List 1) V-Tyre M1 20 121 T_ 14pcs 2) Ecc. bush M1 20 210 T_ 6 pcs 3) Bearing support Base M1 20 220 _? unit 4) Hold Down Idler Stud Shaft M1 30 224 _ 1pcs 5) Pinion M2 30 110 _4pcs 6) Proximity target M 18 027 _ 3pcs Will work out B.Q for structural steel & Fasterner list soon. I am sure to make mistake in the lists. Please feel free to point out any error. Thanks in advance. |
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Still with the project...
Even though the construction of my MechMate is delayed until October under peculiar circumstance; It turn out to be a blessing in disguise. This allow me to take a step back and gather more information & materials required carefully.
The more I study & research, the more I'm sold to this is a winning design! No doubt the design is simple, kudos to Gerald, but gathering all the material, parts and component proof to be time consuming. Not impossible, only require effort... Hey, no pain no gain! I can never show enough appreciation to Gerald and the other wonderful people here for their help and guidance. Now, back to more reading... I have a lot more to catching up & learning to do.... |
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Just to call in to inform that I haven't give up yet
![]() Things started to appear on my door step... The stepper motors, the drivers, PMDX-122 BOB, the racks, V-groove wheels & all the bushes, a set of water cooled spindle and VFD, bearings, connector terminals, circuit breakers, din rails, contactors, old PC, CRT monitor... etc, More stuff are on their way ![]() The spending just never seem to end.... ![]() Unfortunately, I don't get the privilege to open the boxes just yet as I'm away from home for the past month and will not return for another 1.5 months.... ![]() The steel and laser profiles will have to wait until I return... ![]() The good news is that the waiting bought me time to learn my MM further, made some alteration to the original plan and consequently reconcile my needs and want... ![]() Still looking for that special place for me MechMate to play... |
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dude,
got phone number? i'm from johore. |
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Hi all,
I can finally proceed with my MM project. Latest Progress: Found that special place for me MM. Place order for the Laser Cut parts. Will post some pics of the other parts I'd collected as soon as I open them for inspection. Cheers Ken |
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where did you order the laser cut parts, how much do they charge you...
and have you already got the gear rack? all those i found in malaysia is very expensive.... maybe all those factories could afford them, but not for a personal project like this, at least for me. |
#27
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I found at least 6 companies offering such service in KL.
Local rack are expensive, but there are lots of alternative sources which I did not spend enough time to dig, in my case its cheaper & convenient to import. Where about in Johore are you from, it is a big state... |
#28
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Quote:
Send a mail to deitechcontrol@gmail.com and get in contact with Claudia and Harrie. I bought my racks + pinions for less then 150USD (top of my head) Ries |
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I dealt with Claudia. Their rack is affordable.
Nikonault, I did send you many PM to invite you for a group buy but you never reply any... Too bad... |
#30
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Quote:
rasanya saya yang pujuk Claudia untuk mula jual gear rack. tapi lepas tu ada jumpa pembekal lain yang jauh lebih murah tapi ada masalah dengan penghantaran. saya nak telefon saudara, tapi tiap-tiap hari balik kerja dah pukul 11 malam. nanti bila ada kelapangan saya hubungi saudara. |
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