New MM in Cape Town, South Africa

[anton]

Hi Gerlad,
I am looking into a mechmate for routing 6mm to 12mm 5083h321 aluminuim, and a small amount of 20mm aluminuim, for a yacht project. I see from the bend pdf, that the different components of the cars and gantry are made from 4mmm-5mm-6mm, could it all be done from say 5mm, or 6mm, or is there a good reason for selecting some at 2mm and 3,4,5,6 mm etc.

I also had a look at the Shopbot website, and they use the Vextra alfa motors which have builtr in everything, is it beneficial to use these, or the individual motors, and gecko drives?

Do you have plans for doubling up on the z-car so that the spidle is suppoted from both sides?

Cheers,
Anton

[hennie]

Hi Anton, use the plans as per Gerald`s design don`t change on some thing that has proven itself.We all have used motors from all over the world and up to now, no problems.Advice that we can give you is to start reading the treads you will pick up a lot of tips.

[Gerald D]

Anton, I am not going to be drawn into mods for cutting alu.

[javeria]

May be you can use this setup for Z - to cut alu - just a suggestion - not a recommendation

have fun in ur build

http://www.mechmate.com/forums/showt...?t=1298&page=2

[Richards]

The Oriental Motor Alpha motors that Shopbot uses with its PRT-Alpha and PRS-Alpha machines are NOT necessary. I own a PRT-Alpha and have upgraded to the 7.2:1 Alpha motors. Those motors are excellent, but ONE Alpha motor/driver costs as much as FOUR G203v stepper drivers/PK299-F4.5A motors.

As far as I know, there is no CNC software (Mach 3 or Shopbot) that synchronizes the axes when a motor goes into 'alpha' mode. Having one motor momentarily slow down or stop and then catch up almost always guarantees a ruined part. Believe me when I say that I ruined a lot of parts before I finally slowed things down so that none of the motors entered 'alpha' mode.

An Oriental Motor PK299-F4.5A motor when connected unipolar (half-coil) with a 3.6:1 belt-drive will produce about 2X the torque of a 7.2:1 Alpha motor, so, the PK299-F4.5A motor with a belt-drive transmission could be run faster and harder than a geared Alpha motor.

The standard Mechmate with Gecko G203v stepper drivers and commonly used stepper motors will cut anything that a Shopbot Alpha model can cut and the Mechmate will have less flex than the Shopbot. I bought my Shopbot in 2004. If I were starting out today, I would download the Mechmate plans and order the parts. The end result would be a better machine and many thousands of dollars left in the bank, compared to buying a Shopbot.

[PEU]

Anton, I would not advise asking for modifications without prior work on your part, do your homework redesign yourself what you need to change to cut alu, this shows commitment on your part and maybe you will receive better help afterwards, this is true in this forum and in others too.

Good luck! I will keep an eye on your developments


Pablo

[anton]

Thanx to all for the reply's,

But my question is actually this,

I am weighing up the option of having the required materials cut, for 12000$ plus, or building a machine to do it, and then have a assest that can do all the other joinery work as well, but I need to know for sure that the Mechmate built off Gerald's plans with the PK296A2A-SG7.2, 2-Phase Stepping Motor can to reasonable degree of acuracy cut aluminuim?

Any suggestions as to whether the belt reduction system or the direct drive with gearing would work better?

All replies much appreciated,
Anton

[domino11]

Anton,
Yes there have been people that cut aluminum with their Mechmates. Have you seen this post? Found this with the forum search function.
http://www.mechmate.com/forums/showt...light=aluminum

there is a link in that thread to JRs build thread where he cut out his own belt reduction plates on his non geared (at the time) Mechmate.

[Richards]

Cutting 6061 aluminum on my Shopbot PRT-Alpha was not much fun.

Basic data:

1/16th inch depth per pass
1-inch per second move speed
15,000 RPM spindle speed
1/4-inch spiral cutter

The parts were belt-drive transmission motor mounts for my Shopbot cut from 1/2-inch thick aluminum. Edge quality was fair to good (about the same as I normally get when cutting MDF). I tried using WD-40 and then cutting oil, but that was too messy. I also tried blowing a constant stream of air against the cutter to cool the cutter, but that blew aluminum chips all over the shop. Basically, I decided that cutting aluminum was a once-in-a-lifetime experience that I don't want to repeat. Before I ever try it again, I'll add CNC controls to my vertical mill. That vertical mill was designed to cut metal. My Shopbot was designed to cut wood.

[WFY]

I have a program that tells the speed, feed etc. requirements for machining various materials. This is what is shown for 6061-T6.
OPERATION TYPE= Finishing
MATERIAL= Wrought Alum 6061-T6, T651 (95 HB)
SURFACE SPEED= 508 FPM
ENDMILL MATERIAL= HSS
ENDMILL DIAMETER= 0.25 inches 6.35 mm
LOAD PER FLUTE= 0.002875 inches
NUMBER OF FLUTES= 4
SPINDLE SPEED= 7761 RPM
FEEDRATE= 89.2515 IPM 2266.9881 mmPM
MAX Radial Depth of Cut= 0.005 inches
MAX Axial Depth of Cut= 0.5 inches
MATERIAL REMOVAL RATE= 0.22313 in³/min
MATERIAL POWER CONSTANT= 0.33
REQUIRED HORSEPOWER= 0.08663

Here is the software link to the site http://www.machinist-toolbox.com/

[anton]

Originally Posted by domino11

Anton,
Yes there have been people that cut aluminum with their Mechmates. Have you seen this post? Found this with the forum search function.
http://www.mechmate.com/forums/showt...light=aluminum

there is a link in that thread to JRs build thread where he cut out his own belt reduction plates on his non geared (at the time) Mechmate.

Thanx very much Heath,
I watched the video on youtube , and what a relief to see it cut 12mm alu like nothing. I am all geared up to start building my Mechmate now!

Thanx a million,
Anton

[anton]

Originally Posted by WFY

I have a program that tells the speed, feed etc. requirements for machining various materials. This is what is shown for 6061-T6.
OPERATION TYPE= Finishing
MATERIAL= Wrought Alum 6061-T6, T651 (95 HB)
SURFACE SPEED= 508 FPM
ENDMILL MATERIAL= HSS
ENDMILL DIAMETER= 0.25 inches 6.35 mm
LOAD PER FLUTE= 0.002875 inches
NUMBER OF FLUTES= 4
SPINDLE SPEED= 7761 RPM
FEEDRATE= 89.2515 IPM 2266.9881 mmPM
MAX Radial Depth of Cut= 0.005 inches
MAX Axial Depth of Cut= 0.5 inches
MATERIAL REMOVAL RATE= 0.22313 in³/min
MATERIAL POWER CONSTANT= 0.33
REQUIRED HORSEPOWER= 0.08663

Here is the software link to the site http://www.machinist-toolbox.com/

Thanx WFY,
I am busy downloading it as we speak, can't wait to try it out on the actual machine

Anton

[Richards]

Anton,

Did you notice that the data that Buzz posted was for the finishing pass? The cutter is only taking 0.005" off.

When rough cutting, pocketing, etc., you'll probably be stepping down at about 0.06" per pass and stepping over about the same amount, depending on the cutter that you use. In other words, pretty slow going.

[skypoke]

Anton,

I'll second the suggestion to look over this thread, poster Maxman does exactly this type of cutting of marine grade. He's passed along some very valuable advice based on experience.

http://www.mechmate.com/forums/showt...light=aluminum

I'm cutting some 5083, it's tough stuff compared to 6061, very gummy. I have seen no reason to upgrade anything from standard Mech. I've had some good luck with 1/8" solid carbide double flute bits. We're about to start a production run of small skiff parts.

Chuck

[anton]

Hi Guy's,
Absolutely the most comprehensive collection of info on building a damn good CNC machine. I have been going through the thread over the past few weeks, and everyday I am more impressed, both with the site, but foremostly the design(MechMate), well done Gerald!

I have gone ahead and started purchasing the goods, I am out of country (traveling contractor), so I have most of the electronics, motors, drivers, power supply etc purchased already, and in various phases of being delivered.

I am battling to get hold of Superior Bearing, do any of you guys have a e-mail for rick at superior bearing?

Hi Gerald, do you know of a reliable CNC laser cutting shop to have the parts cut, and a engineering shop for the bending?

I hope to be posting pictures of parts and progress on assembly in the next 5 weeks.

VERY EXCITED !!!

Cheers,
Anton

[Alan_c]

Schuurman Laser cut, they can also do the bending.

See here for all the info re bearings.

[sailfl]

Anton,

I sent you a PM.

[Doug_Ford]

Anton,

I hope you have a beard. If not, you better get started growing one. Unless the rules have been changed without my knowledge, the South African members of this forum are required to have a beard (and a boep would be nice too.) Check the mug shot thread.

[anton]

Thanx for all the info guy's, it is all starting to come together. Can I upload foto's to this thread, or only link's to foto's?

Anton

[anton]

Sorry no beard or boep, there are some foto's on my facebook site, "Anton Sidney Hart, Cape Town, SOuth Africa".

I posted a reply on the bearings/rails thread regarding Rick at Superior Bearings. Has anyone got hold of him in the last few months, as I am getting no reply from him. It's been almost 2 weeks now.

Anton

[domino11]

Anton,
Yes you can upload photos here.

[anton]

Eventually got my ducks in a row, and have made some decent progress on my MM.
Some of the table legs.


The Y Gantry.






Gantry all done.


Started with the x-bearers.


Started with the Y-car.

[BartDeckers]

Hi Anton,

Moving fast, success with you build.

[Claudiu]

Hi Anton,

nice progress...please tell me what type is that white car? Looking fast..

Greetings
Claus

[Gerald D]

Good progress Anton. I have merged your two personal threads into this one.