Steve are you running the transformer direct or do you have a bridge rectifier and capacitor filter on the output side? What are you using for the 37mA load and how are you doing the measurements? DC or AC range on the meter?

Heath,
The problem was that the NEW 12v DC power supply I purchased from Radio Shack was bad. Before I installed it into my power panel I did check it for polarity and got a 12+ volt DC on my voltmeter. However, at the time I didn't have any componets to test it under load. Now that I'm ALMOST ready to cut something I found that the power supply would crash when any load was applied. It simply would lose all voltage. It was rated at 1.5 amps so there should have been plenty of power. I replaced it with another and everything works fine.

Limit Stops Question
 

Now that I have my MM to 'home' and the X,Y limits work I have another question. I configured my system to work the way Seans system does. This system can be found under the 'Proxies & Limits' discussion in another post. Basically, Sean wired proxy sensors to a relay board that used one common pin to the BOB. I find that with this system that the X-axis only requires one proxy. The X-2 (A) axis proxy is just redunant unless you consider the possibly that that side of the gantry could somehow derail. Is this thinking correct? Also, why would I need to enable the X-- and Y-- limits in MACH when I find that the X++ and Y++ limits trip anyway when reaching the opposite ends of the rails?
Steve

Steve,

I've been running my MM with one prox. (the way you describe) on the X-axis for awhile now. Never an issue and runs great.

Steve,
To further our discussion via PM, the x1 and x2 are redundant, but used for the derailing of the machine during an event. My machine #5 would often get derailed because the operator would leave an air hose, shop rag or other hanging on the rail and it would derail. Often only one side....thus the prox's on both sides of the machine.

Sean

Sean,
That would be a GOOD reason to activate the other X proxy!:eek:

Houston-we have lift-off!
 

Making dust!:D
I would to thank, like many before me, Gerald for his great design and generosity in allowing the world to benefit from it. I also want to thank all of the people in this forum who have contributed many hours of their time in finding great solutions to building the MM in the best possible way. So, without further ado here are some pics of my MM’s first cuts of the infamous ‘Roadrunner’…

Steve,
Awesome! Congratulations. Glad to see your well on your way....building it was only part of the challenge. Using it is another whole new skill set.

I can't wait to see your first production part.

So, what the heck number are we up to now? I remember the race to 3, 4 and 5......

Sean

I'm hoping its '66' (route 66).

That would be an excellent number. Congratulations! I remember pushing to get the "last" serial number, back when we were going to stop numbering after 10. Based on that, I think Mike should declare that 100 will be the final serial number. Heck, some people might even believe it ;)

How close are you to getting your kicks in Flagstaff or Winona?

Congrats Steve! :)

Well done! Congrats!
Now the fun had just begin。。。

Well Done !!!

Congrats !!!!

#66 it is for you !!!

Congrats Steve,

The fun is only starting. :)

A long awaited moment you cherish…..
Congrats Steve and good luck sorting out it’s quirks ;)

Builder's Log Update
 

Steve,

Congratulations on a fine looking MechMate and Serial #66.

Here is the Updated Builder's Log.

Please let me know the dimensions of your MM for the Builder's Log.

Also, please review your entry and let me know any changes you would like.

Adjustments
 

I want to thank all the well wishers for their support!
I've been learning the fundimentals of Mach3 and tuning the beast. The first question I have is about slop. I find that the motors (PK296A2A-SG7.2) when turned on and engauged into the rack have a .030" total slop when grabbing the router collet and applying hand force in the Y direction (both Y++ and Y--). I have adjusted the springs to their tightest location and that helped allot. When adjusting the springs and with the motors still on I found that the shaft of the motor would slop that amount by turning the gear by hand. I assume that this is normal for this motor. The X direction only has a .010" slop and I assume that is because there are two X motors and if they are not perfectly the same in each rack then one will lock the others slop out somewhat. So far I cannot find anything else that would cause this condtion. Can anyone please advise?:confused:

Have you checked the grub screws holding the pinion gear to the motor shaft, it has a sneaky habit of loosening up. Do a search on the forum, there are plenty of posts regarding this.

Alan,
Indeed, the grub screw was loose. Also, I'm finding that the 10-32 thread in the pinon from the manufacture is just too small to lock to the shaft of the motor. I have tightened the screw to the point of bending/twisting the allen wrench and I still get play/slop in the pinon. Nils, AKA Sailfl, had a simular problem with his machine and reworked the pinons to take 1/4-20 grubs. That is what I will do and report back as to the outcome.
Steve

Z-proxy
 

I decided to add a Z-proxy and here is my solution to its placement. I used a metal 'nail protector' used in housing to prevent the trades from nailing into water pipes/electrical and the like. Simpson Strong-Tie would be a name brand. I drilled two small 6-32 threaded holes in the spider to accept the plate and the slot for the proxy was created by drilling some holes side by side and then filing the flat of the slot. The proxy 'sees' the edge of the Z-stiffener. When the Z is fully in the up postion the metal of the stiffener is above the proxy thus tripping the limit.

PS- As stated earlier I'm no welder, so if anyone notices the gaff in the bottom vacuum holder, I'm still experimenting. Using a 'stick welder' on thin material is challenging.:o

Steve,
If that little gaff is the worst you did with a stick on that thin stuff, I congratulate you. I would not have tried that without a mig. Even then it is not that hard to get burn through on thin stuff. :)

Steve, I impressed that you can even use a stick welder on that thin stuff! :)

Slop
 

Well I have retooled the pinons with 1/4-20 grubs. Used a 3/8" ratchet to tighten them. The motors have a slight movement/slop by themselves. The pinons appear to be solidly attached to the motors shaft. Using a dial indicator with the motors turned on and grabbing the router collet by hand and applying some force, I get a .005" slop up and down in the Z axis, a .030" in the Y-axis and a .010" in the X-axis. Can anyone tell me if I should be getting better values?

I read about the .005" backlash that my motors have built-in. So, measuring with the dial indicator placed on the gantry and touching the Y-car, it indeed would move the .005" only, therefore confirming that there is no loose pinon in the Y-motor. I also noticed that I measured this from a different location than before, so I measured the Y-slop at the router collet at this position. At this location I only get .010" slop instead of the .030".

Steve, are you pushing with your hand to figure out the backlash?

If you are pushing you are measuring deflection. This means all your doing is fight the spring that is attached motors. This is also the reason for ruff cutting a finishing passes.

To measure backlash you would need to move the axis under power. Similar to this http://www.youtube.com/watch?v=1c5ZzxlhMq0

If you are measuring under power and you are still ending up with these numbers something is loose or your steps per is off a little. You will not end up with zero but you should be pretty close to the factory's .005

By the way great looking machine you built there. Looking forward to seeing what you make with it.


Just out of curiosity how long did it take you to paint all the nuts, bolts and washers. :eek::D

Builder's Log Update
 

Steve,

Thanks for the information.

Here's the Updated Builder's Log

Russell,
Thanks for the reply. Yes I was pushing by hand. I spent some time ajusting and then learning enough G-code so I could run some cut tests. I ran a 45 degree diagonal line and a circle. The line and circle showed no chatter!:D The circle came together exactly wher it began! Gerald your design is so sweet!:)

Cam
 

I'm trying to get my head around the way some people decide to set up a large wood cutting CNC. When looking at the Mach and CNCzone sites I find that there are many that operate metal mills, not so much wood routers. So some of the assumptions I have made may be in error. The author/programmer/user of the CAM software I have chosen to use has made the software to default to following...

1) A spoil board will need to be used.

2) The 0.0 Z plane is at the surface of the spoil board.

3) The values for the different tool path levels are “inverted”, meaning negative numbers are above 0.0 and positive numbers are below 0.0 or down into the spoil board.

Also, he has defauted to using absolute coordinates instead of relative.
He has provided the means to change these settings, but looking at his approach, it seems to make more sense in panel processing with a spoil board than the Mach3 method which I assume again was written more for the metal mill CNC. e.g. dosen't have any spoil board.

In reading the Mach3 docs I'm assuming that the Z-axis 0.0 setting is on top of the work piece and sending the cutter down into the work uses negative numbers.

These two approaches would produce very different G-code.

I would like any thoughts on these different ways to process panels.

Thanks

Which software is that? It sounds very unconventional.

Gerald,
The software is VCamm and intergrates with VCadd, the CAD software I have used for my drawings for years. This is the first time I have used VCamm.

Gerald,
Also, by your response I assume that this is not the method you would recommend using? :confused:

I am not recommending anything - simply observing that Vcamm is apparently forcing you to be the opposite of 99% of other CNC operators.

Steve,

I've been using Vcarve Pro for a year or so. Great program, in my opinion. I set my Z = 0.000 at the top of the part I'm making. All cutting is in the negative Z direction. Just my preference. Vcarve Pro lets you set it where you prefer.

You might want to checkout Vectras site and their tutorials for another reference.

You'll get it. :)

Dust Foot
 

Among other things I needed to make a dust shoe for my machine. My router is the Makita model 3612. First generation. Have had it for 28 years. As ‘Scotty’ said in an episode of Star Trek NG, “No B, No C, No D”.

The type of dust system I decided to implement is the ‘fixed’ style of dust shoe. The problem with that is the router’s massive body size. It isn’t round so I had to come up with a design that would allow it to go below the base of the dust foot. I chose the brush Gerald recommended in his post on building his dust shoe. I wanted to keep the entire length of the brush, which is 4”, so it would be sure to ride over any clamps. The photos that I show of the sheet metal prototype was modified smaller, because in the end I had to cut away some of the router’s body parts otherwise the shoe would have been a sasquatch (big foot).

After the sheet metal work I set up to do my first real cut part on the MM. It was the stiffener for the sheet metal dust foot. I decided to make the first one out of ½” Baltic birch ply. I used a ¼” cutter with a ½” shank and two straight carbide tipped bits. The tip measured .008” under the ¼” diameter. I’ve had it for a long time so I’m sure it has been sharpened over the years. Anyway, I set the material in the machine, loaded the G-code and let her rip!

The part that came out is amazing! The dimensions I measured with a veneer caliper are only off by .002”, if you consider the undersized cutter and that I cut the part without compensating for it. The finish is pretty flawless. There is a slight run-out on the smaller of the two inside circles, the fillet on one side only shows a little chatter and the rest of the part fine. I haven’t checked the X-Y axis for square nor the Z axis yet. I haven’t surfaced the spoil board yet either. I’m very pleased with the machines ability to keep this kind of tolerances! In no small part due to Gerald’s design and this groups refinement of critical steps in the making of the beast.

I also added the shelf Gerald suggested over the control box to protect the G-540’s DIN plugs.

PS. A 3' long brush ended up being too short so I'm awaiting McMaster-Carr for a longer one

very nice cut quality

Z-Slide final ajustments
 

Hey Gang,
I need some advice. I have adjusted my Z-slide according to the post Gerald made using a sheet of glass, framing square and trammel. In my case I swung a dial indicator around with a 6" radius. After 'squaring' the Z plate, I mounted the router. I do not have a precision router holder. I made one like that shown in one of Geralds posts because I have the Makita 3612. It does have the steel dowel locators which will position router holder in the exact same spot every time it is remounted to the Z slide. I used 'stand-offs' like Gerald, but mine are removeable when the router is removed from the holder. I set my dial indicator up and swung it around on the sheet of glass. The first reading showed .150" height difference in the diamater (12") in the Y direction. No difference in the X direction. Using my CAD program I caculated how much material I needed to remove from two of the stand-offs to right the router in the holder. After I had obained a difference of only .030" in 12" I remounted everything to do an experimental cut. I should mention that the reason I settled for the .030" is because the amount that I would need to take off of the two stand-offs would .001". I could remove that amount by placing some sandpaper on a flat surface and gently sand the base of the stand-offs, but I wanted to see what would happen first.

The pictures below show the before and after. I cut a rectangle pocket using a Mach3 wizard. The cutter I had to use was a 13/16" WKW 68604 straight double flute with NO flat bottom. I'm ordering the Onsrud surfacing cutter, but I haven't decided on the spiral cutters yet.

So, after this long intro, here is my question. How close is close? Are most of the machines set-up so that the 'lawnmower' effect is non existant? The second photo, the adjusted Z, has slightly visible lines in the cut. You cannot feel any 'steps' when you run your hand across. Where the cutter 'turned' the corner 'steps' are a little more noticable than anywhere else. I'm I wasting my time at this point because the cutter I'm using is wrong for this kind of cut? Should I go back and take out that .030" travel in the 12"?

Any thoughts would be appreciated.

Before: 1st Pic

After: 2nd Pic

Steve, I think you have done particularly well and can stop trying to get it better.

That's better than my setup. :o

Nice job Steve.

Gerald, Greg... Thanks for the kind words and advice. I will move on the final squaring of the X and Y.

Gareth... sorry, thank you also for your kind words!