Just Starting Out and Need Help

[bnoji]

I'm just getting started in machining and I'll be taking a few classes at the local community college (I might as well since it's free). My brother and I wanted to get a small setup for use/practice at home. My brother is familiar with machining, but not CNC.

I'm not sure whether to get a dedicated mill and lathe or a 3-in-1. We're mainly concerned with the quality as we're going to be using it to create certain parts for interference fit.

I was looking for something I can convert to CNC later (kit or homebrew)

Two requirements we have are:
1. The abillity to mill on steel approx 8in x 12in x 4in (I have a model of a specific shape that we would like to cut if it makes a difference on the max size)
2. The ability to ream a 3 to 3.5 inch hole in the above piece for a press-in bearing.

Our budget is $2000...I guess I'd like something I won't outgrow.

Thanks.
Ben

[acondit]

Ben,

Look at the Grizzly G0519 specifications below (basically a RF45 or clone thereof). The 12" on X-axis is no problem and the 4" on Z-axis is no problem but the Y-axis is only 7.5". I believe that on a CNC conversion you can actually gain a 1/2" to 1" on Y travel. Industrial Hobbies used to sell a machine that would meet your specs but it was about $2200 w/o shipping and he is not selling them any more.

To find a stock machine that has more than 8" of travel on the Y-axis you are probably looking at a Bridgeport or clone thereof. You might find a used Bridgeport for $2000 or less.

Specifications: (Grizzly G0519)

* Spindle taper: R-8
* Spindle travel: 4-15/16"
* Quill diameter: 2.95"
* Table size: 9-1/2" x 32-1/4"
* Table width end to end (tip of handwheel to tip of handwheel): 45-3/4"
* Table travel (longitudinal): 21-5/8"
* Table travel (cross): 7-1/2"
* Max. dist. spindle to table: 18 5/8""
* Max. dist. spindle to column: 10-1/2"
* Machine depth (back of column to tip of front handwheel): 31-1/4"
* Machine height 55-1/4"
* Head tilt: 90º both ways
* Head swivel: 360º
* T-slots: 4 slots, 1/2" studs
* Range of 6 speeds: 120-1970 RPM
* Motor: 1 HP, three-phase, 220V
* Approximate shipping weight: 673 lbs.

Good luck,
Alan

[bnoji]

Thanks for the help. I'm sorta lost when it comes to machining. I've been looking at the Grizzly models and my brother and I decided to split it. We can stretch the budget a little since it's worth it in the long run so if there's one that's just a little more but worth it, I'd still be interested in looking.

Does the type/brand of machine impose any limits on CNC conversions? What features should I be looking at? I see several with round vertical columns, some with dovetails and some which rotate at the head.

I'm a little wary about buying used equipment because I don't know what to look for in a properly functioning machine...let alone how much it would cost to repair if it had something obviously wrong with it.

ETA: In terms of the Grizzly machines...after shipping, I suppose we could afford the G3102, G3103 or even the G1126.

Thanks again.

[acondit]

Ben,

I just went to the Industrial Hobbies website. It appears that Aaron Moss found a buyer for his business so, they will be selling his version of the RF45.

http://industrialhobbies.com/

I think this might be just what you are looking for. Also the IndustrialHobbies website has a lot of info on CNC conversions of the RF45 class machine.

Also search for some of the RF45 conversions and look at the bridgeport machines. On the east coast you can sometimes find a real buy on a used bridgepost on eBay.

Most people recommend that you avoid a round column machine for CNC conversions (especially if you don't already have it). So that would argue against the G1126.

The G3102 and 3103 only have 6" Y-axis travel, so they wouldn't seem to meet your specs either.

In the Grizzly line you would have to go with something like the G6760 to find something that would meet your specs without modification, which with freight is a little over $3000.

Alan

[MOOG B-22]

Don't Waste Your Money On Toys. Find A Good Deal On A Used Bridgeport. There Are Lots Of Attachments, Heavy Duty Enough To Put Almost Anything On, Can Be Cnceed Later, With A Set Of Digital Readouts It Can Do Wonderful Things. I Think The World Was Built Using Manual Machines. Most Of Them Were Bridgeports. Some Have Power Feeds Which Can Leave Excellant Finishes. Just About All Machine Shops Have At Least One Or Two Of These. Variable Spindle Speed Is Also A Great Benifit. Wish I Had One Myself. I Have Operated One For Twenty Years Off And On. Be Patient And Don't Waste Your Money.

[ZipSnipe]

The Bridgeport is the ultimate mill IF you have the room for it. If space is a concern then what Acondit suggests is the next best bet. Heres a link to an even cheaper source http://www.wttool.com/product-exec/p...ovetail_Column
Wholesale Tool Company - Industrial Machinery, Industrial Supply, and Tool Supplier - Geared Head Mill & Drill Machine w/Dovetail Column

Enco has it for about the same price too. I was set on getting one of these but then I built my own mill and am quite happy with it(even through I started working at a die and mold shop and have full access to Bridgeports and etc.)

[ViperTX]

$2K budget and you want to mill and bore steel.......well I'm with ZipSnipe and recommend that you find yourself a nice used Bridgeport...not sure what part of the US your in...

If you want to work steel....you'll need the mass of the Bridgeport...even an Enco or Grizzly large knee mill would be fine.