What ends mills should I buy?

[CamSec]

I tried posting an update earlier, but was having browser problems (it never ends), I finally got it working! Not sure if it was removing the controller lid and pointing a desk fan at the back of the Gecko as suggested by deepgroove1, or tightening the backlash nuts. I`m crossing my fingers and preparing the next part now, hope it keeps working.

[awetmore]

I'm guessing that it was the cooling since that looks so much like missed steps. I've never seen backlash that would act like that.

I'm surprised that the Deepgroove1 enclosure doesn't include a fan for the G540, but that is a fairly easy thing to add.

[cameraguy]

-MUST- keep air on the back of those Gecko 540's. Doesn't require much, but you have to keep a fan on them moving air. I use a mini computer fan in the case. You can find 110v fans if you look, find a dedicated 48v fan (rare), or put resistors or a voltage split or a VRM on a 24v or 12v fan.

[CamSec]

So all my problems were simply due to bad soldering on the motor cables, loose wiring in the controller, and not having a fan? Deep breath, deep breath..

[awetmore]

There is a downside to the deepgroove1 kits and a reason why they are hundreds of dollars cheaper than the next cheapest option. On the other hand I think they are the cheapest way to get a Taig mill, Gecko G540 controller, 3 stepper motors, and a 48V power supply. It might be best to think of them as a kit of parts that needs to be assembled by the end user.

[cameraguy]

It might be best to think of them as a kit of parts that needs to be assembled by the end user.

I second that notion. Deepgroove has historically had some quality, service, and, how to put this nicely - we'll just say 'ethical' - problems in the past, but the parts he supplies are usually good.
If you know what you are getting into you can get the components you need a bit more cheaply than elsewhere, but don't necessarily count on service, support, or proper assembly. Also, you sometimes take the chance with his motors as though he sells them as new, some of them he has historically sent are actually used - surplus from the petrochemical industry. So, if one axis seems off for some reason compared to the others, swap the motors and make sure a bad motor isn't the problem. He does need to replace a bad one sometimes.

Just double check everything and you should be fine. The underlying parts are all reputable bits. Next time just think twice about the savings and how much time and frustration you have spent over those savings!

[CamSec]

Thanks to everyone's help I`ve managed to ship the first small batch of my product. I`m having lots of problems producing good parts from the molds, but I sought some advise on that so have a compression pot and new and improved silicone and resins on order, so I`m hoping that will help.

In the mean time, I really want to improve my work holding system so I can reliably do two sided milling. I have a 4" wide matrix plate, but it isn't really designed for 3"x12" blocks, and I`d like to be able to mill 4" wide blocks. The main problem I`d like to solve is preventing the block from being pulled up off the table (I`m not using climb milling). Tightening the cam screws also pushes the blocks up off the table, especially after one side has been milled and the block is more flexible. The second problem is all the blocks are slightly different sizes, so something that automatically centers the parts would be really useful to make sure everything lines up when flipped over on the Y axis. I bought this self centering vise, http://www.amazon.com/Woodstock-D4064-Precision-Self-Centering/dp/B005W16TH0/ref=sr_1_4?ie=UTF8&qid=1332107106&sr=8-4]Amazon.com: Woodstock D4064 Precision Self Centering Vise: Home Improvement, but its way too big for the Taig. Does anyone know of a smaller vise like this that would fit? I haven't had any luck finding one so far.

I was looking into buying the 4th axis upgrade, but I`m dubious about it being able to securely hold a 4"x1"x6 or 12" delrin block? If it can handle it, what kid of chuck would I need?

Another option would be to make a custom fixture for the blocks, but I haven't had any really good ideas on how to make something precise enough so that when I flip it over to mill the other side, everything still lines up.

Any suggestions will be greatly appreciated.

[Jeff-Birt]

Here is what I do:

1) register the stock in the back left corner of a fixture plate (I put a few short allen head screws in the plate, two along the back and one on the left.)

2) use a wiggler to find the rear and left sides of the stock and set those positions to (0, 0).

3) measure the stock and move each axis 1/2 that distance so the bit is now centered on the stock. For example I'm at X=0 and the length of the stock is 4.02". I set the X axis scaling to 0.5 and type 'G0 X2.02' in the MDI line in Mach and mach will scale this distance by 0.5 (scaling entered above). Now I am at the center of part in the x axis and can reset DRO to 0.000 and the scaling to 1.0.

This procedure centers the machining on the stock. Of course your GCode has to be set up so the machining origin is in the center of the stock as well. It is very useful to account for small differences in stock size. For example I sometimes machine really small microwave wave guides, adapters, detector housings,etc and centering like this will allow all the pieces to align up properly for assembly even if the stock for one of them is 0.001" off.