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asbrandsson
02-10-2008, 11:22 AM
Hello,

I am going to get one of these Sherline CNC mills -

http://www.sherlinedirect.com/index.cfm?fuseaction=product.display&Product_ID=185

and was wondering if anyone already has one or has experience with this kind of stuff and can tell me if this is the best hobby level CNC mill to buy.

Asbrandsson

JonHylands
02-10-2008, 12:32 PM
I have one, although it is using a 3rd party control board, and I use Mach3 for CAM work.

I like it - I've been using Sherlines since 2000, and I think they're great for someone like me, who is more interested in building robots than figuring out how to make a less-high quality machine work.

- Jon

asbrandsson
02-10-2008, 06:45 PM
Hello,

Are they easy enough to figure out with little to no training. I am like you, I am more interested in making a robot and not interested in car parts. I can get CNC done locally, but I am affraid of my designs suddenly appearing in China.

They also claim that you can etch electronic boards with it as well. Have you any experience doing that sort of stuff?

Asbrandsson

JonHylands
02-10-2008, 07:09 PM
Well, unless you know how to do machining already, I would strongly advise you to take a course on machining, or plan on working very slowly from a couple of good books, learning as you went.

I had a Sherline mill for 6 years before I got a CNC mill...

I have not done any electronics - I prefer to outsource that.

- Jon

asbrandsson
02-10-2008, 09:51 PM
Hello,

Can you make exact parts without the CNC portion of it?

Asbrandsson

JonHylands
02-11-2008, 06:21 AM
Yes, although there are some kinds of parts you can't make without CNC - like parts with curves. It really depends on what shapes of parts you're looking to make.


- Jon

asbrandsson
02-11-2008, 06:33 AM
Hello,

I really want to just make custom brackets. I think things like the double knee and double elbow are the future, as well as torso that will fit the parts I want - things like the Hitec 5990TG for the shoulders and various other things. If I could get an image of an i-droid head I would CNC one out of a block of aluminum.

Abrandsson

JonHylands
02-11-2008, 06:58 AM
You can do brackets on a regular mill, as long as all the angles are 90 degrees, and there are no curves. Of course, for things like that, a CNC mill is a whole lot nicer.

I'm not trying to dissuade you from getting a CNC mill - my point is to use a CNC mill, just like to use a regular mill, you have to understand the process of machining. Using a regular mill, it is much easier to learn, because the hand-wheels give you feedback before you do something stupid. With a CNC mill, the stepper motors are quite happy to drive your end-mill through your milling vise, or whatever else is in their way, if you make a mistake in your calculations. A couple months ago, I was doing some manual machining on my CNC mill (which involves punching in lines of g-code directly to move the milling head around), and I accidentally left out a minus sign. The mill head moved where I told it to, and snapped off my 1/8" end mill against the milling vise (the mill wasn't running at the time).

- Jon

jdolecki
02-11-2008, 07:26 AM
I use Mach3 on my home built Bridgport CNC, it's trial verson is free and the full version is 149.00 I think. If your intrested in building your own CNC here is the place to go.

http://www.machsupport.com/artsoft/index/index.htm

Alex
02-11-2008, 10:07 AM
A couple months ago, I was doing some manual machining on my CNC mill (which involves punching in lines of g-code directly to move the milling head around), and I accidentally left out a minus sign. The mill head moved where I told it to, and snapped off my 1/8" end mill against the milling vise (the mill wasn't running at the time).

Ouch! I used the old fashion hand crank mills back in the day and I loved them. Really straight forward and pretty easy to use. Those CNC mills sound like they can do some major damage if you're not careful...

JonHylands
02-11-2008, 10:11 AM
Yes, but you can do magic with them also...

http://www.huv.com/blog/2007_04_01_archive.html

- Jon

SN96
03-01-2008, 01:27 PM
I have looked into the Sherline mill myself and from the research I have done, some of the larger mills available have warp issues and need to be cleaned and reworked before they can produce any kind of accuracy, even though they are new.

I have also come to like the MachIII software controller because of the video tutorials, which proved helpful for someone like me with virtually no knowledge with CNC. Sherlines are perfect for hobby robotics since the average part is rather small. Battle bots on the other hand would probably require a much larger mill.

Sherlines are great quality from what I can see (I don't actually own one) and the videos on their website was very informative and fun to watch. I have seen the lathes cut just about every kind of metal.

I think buying a sherline is a very wise choice for any newbie. Trust me, I want one real bad but other priorities always wins the financial battle.

Droid Works
03-01-2008, 02:29 PM
Thanks for posting this. It looks like a great deal. I think I may buy one for my self also.

jdolecki
03-01-2008, 06:41 PM
When your on the Sherline Web Site make sure you look at the Master Craftsman Museum.

Some of the thing on there are pretty unbeliveable.

Robin Hewitt
03-03-2008, 09:36 AM
If you want to play the place to go for info is www.cnczone.com (http://www.cnczone.com)

Here's a little movie of mine cutting a spring plate out of half inch aluminium. They are quite entertaining to watch if you are used to doing it the hard way :veryhappy:

http://www.robinhewitt.net/mill.wmv

asbrandsson
03-05-2008, 07:13 PM
Hello,

I just won a cnc mill off of E-bay. Now I just have to pay for it and wait for it to show up. Hopefully it will be here in a few weeks.

Asbrandsson

Alex
03-06-2008, 10:13 AM
Awesome, congrats! Keep us posted:D

SN96
03-07-2008, 06:28 PM
Hello,

I just won a cnc mill off of E-bay. Now I just have to pay for it and wait for it to show up. Hopefully it will be here in a few weeks.

Asbrandsson

I wana see pictures when you get it. :veryhappy:

asbrandsson
03-07-2008, 08:18 PM
Hello,

This is the listing for it. I think that it should be here within a couple of weeks.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEBTOX:IT&item=220206769989&_trksid=p3984.cTODAY.m238.lVI

It should do the trick for making the robot parts that I am looking for.

Asbrandsson

Robin Hewitt
03-08-2008, 03:24 AM
Very pretty, love the case. If you're planning to cut metal rather than plastic, particularly aluminium, I suggest you also invest in a bottle of Rocol RTD Liquid and a brush before it arrives :wink:

JonHylands
03-08-2008, 06:59 AM
I find WD-40 actually works really well for cutting aluminum plate (http://forums.trossenrobotics.com/blog.php?b=13).

- Jon

Robin Hewitt
03-08-2008, 10:15 AM
I find WD-40 actually works really well for cutting aluminum plate (http://forums.trossenrobotics.com/blog.php?b=13).

IMHO, WD40 is great for starting damp engines and has the remarkable property that it dissolves cold bluing without touching the real McCoy.

Penetrating oil and Ambersil 40+ are probably better choices for most things people hope WD40 will do.

If you are stuck for a cutting fluid and only have what happens to be on the garage shelf, car engine oil?

You could probably use WD40 as a mouthwash, but I prefer Listerine.

You could probably use WD40 as a tool lubricant, but I prefer Rocol RTD Liquid :veryhappy:

asbrandsson
03-08-2008, 02:33 PM
Hello,

Thanks for the advice. I think that now I can really get into making the kind of humanoid robot I have wanted to build for the last couple of years. I have been thinking about getting a laser scanner for it to make prototyping a bit easier, in that I can resize things like an I-droid head without having to enter all the data into AutoCAD manually.

http://www.denford.ltd.uk/index.php?option=com_content&task=view&id=96&Itemid=29

I have to contact Denford during the week to see how much it costs.

Asbrandsson

LinuxGuy
03-23-2008, 10:36 PM
I have one, although it is using a 3rd party control board, and I use Mach3 for CAM work.
What would be the largest part you could make, or the longest dimension a part could have? I eventually want to get an aluminum set of decks made for W.A.L.T.E.R. after I get a final design for each deck.

There are also custom brackets I would like to have made. My Alibre Design Expert 3D CAD (http://www.alibre.com) software can supposedly create g-code using the AlibreCAM module, but I don't know anything about machining and would not know how to use that.

8-Dale

asbrandsson
03-23-2008, 11:23 PM
Hello,

I picked up that cnc mill on Wed but did not have time to mess around with until today. Although I got all the stuff with it the company that made it

http://www.denford.ltd.uk/index.php?option=com_content&task=blogsection&id=5&Itemid=30

has a bunch of security features that they use to thwart people from using their product, so I need to contact them tommorrow if I can not get the machine running as it is, but I have not really put alot of effort into getting it running.

There is a local trade school here and they do the apprentice training for machining there so I might be able to find a low level apprentice who will be willing to do some work and show me how it works for a fairly low amount of money.

I will post some picks of the case and everything when I get to the shop tommorrow.

Asbrandsson

JonHylands
03-24-2008, 07:33 AM
What would be the largest part you could make, or the longest dimension a part could have? I eventually want to get an aluminum set of decks made for W.A.L.T.E.R. after I get a final design for each deck.

Well, I can machine about 8-9" on the X-axis, and 4" on the Y-axis. You can machine plates that are 8" x 8" on it, but you would need a special jig, and some indexing holes so you can flip the deck and do the two halves separately.


- Jon

LinuxGuy
03-24-2008, 06:44 PM
Well, I can machine about 8-9" on the X-axis, and 4" on the Y-axis. You can machine plates that are 8" x 8" on it, but you would need a special jig, and some indexing holes so you can flip the deck and do the two halves separately.
Durn. Is there anything reasonably priced that can do up to 12" x 12" stuff, like for robot decks?

8-Dale

JonHylands
03-24-2008, 07:27 PM
For stuff that size, you can look into getting it laser cut - Pololu has a nice service (http://www.customlasercutting.com/)...

- Jon

archcvd
03-25-2008, 12:57 AM
For stuff that size, you can look into getting it laser cut - Pololu has a nice service (http://www.customlasercutting.com/)...

- Jon

It's a shame they don't cut any metal... :(

Robin Hewitt
03-25-2008, 04:31 AM
It's a shame they don't cut any metal... :(

There's ebay item 3869848989 if you want it in steel. Plasma is cheaper but less precise due to the kerf.

LinuxGuy
03-29-2008, 05:53 PM
It's a shame they don't cut any metal... :(
I looked at them, and saw they do not cut metals. I think I would prefer to work with somebody or a company that is local to me anyway.

8-Dale

cmmguy
03-29-2008, 08:27 PM
Find a local fab shop that has a laser... but you will find that laser does not cut aluminum very well(reflectivity problem)

asbrandsson
03-29-2008, 08:42 PM
I looked at them, and saw they do not cut metals. I think I would prefer to work with somebody or a company that is local to me anyway.

8-Dale

Hello,

The problem with that is two fold, one is that it is expensive to make one off parts locally (unless you know the people or person who owns the machine and they are willing to do it for nothing as help to you). An industrial machine is very expensive. I bought a used Denford CNC Micro-Mill that was made in 2000 for about $2000 USD that same set up new is $10 000 USD which is out of my range. However, with a fourth axis I can make any 3D robot part I want.

I found a way to scan images into 3D models using -

http://www.david-laserscanner.com/

However, the second thing about getting someone locally to make parts for you is that they can take your design and make it themselves or sell it to other people who can. Which for some things matter and other things do not.

Asbrandsson

LinuxGuy
03-29-2008, 09:31 PM
The problem with that is two fold, one is that it is expensive to make one off parts locally (unless you know the people or person who owns the machine and they are willing to do it for nothing as help to you).
Other then robot chassis decks, all the stuff I would want to make are brackets and similarly sized things.


I found a way to scan images into 3D models using -

http://www.david-laserscanner.com/
This is cool, for sure!


However, the second thing about getting someone locally to make parts for you is that they can take your design and make it themselves or sell it to other people who can. Which for some things matter and other things do not.
I don't think any reputable outfit is going to want to even be accused of such a thing, much less be caught doing it or having done it. Naturally, I would not want to see this happen to anything I have designed, but I also think looking over your shoulder like this would be somewhat paranoid.

8-Dale