My milling machine setup & thoughts

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It’s been awhile since talking about my tooling setup but I haven’t thought much about my milling machine since getting it set up. I guess that’s a good sign, eh? It works for what I use it for, even though it’d be great to have a bigger machine.  I’m putting it to test more now that I’m starting to do some actual milling instead of using it as an oversized tube-notcher.
I got it about two years ago after looking online for a used one for several months.  I realized Colorado is not a great place to buy a used milling machine.  Were I motivated enough to drive back east and pick up one back there…then it’d be easy. They’re a dime a dozen there it seems?!  Finding a big Bridgeport in this area is rare, and if they do they’re overpriced and disappear quickly.  Anyways, that’s why I went with a new Made in China/sold by a US company mill – the Grizzly G1006 mill/drill.  I saw that a couple of my framebuilding influences (Rock Lobster, Hunter, Coconino) had a similar round column mill and use or used a setup with a 3-jaw/tube vise aItached to a rotary table on the mill’s bed.  Going that route too I found that it’s a relatively cheap and versatile setup.  You can quickly miter main tubes, including the downtube counter-miter, with the 3-jaw vise, and then miter the stays either individually on the milling vise or with another fixture using the other half of the table.  You need a 8″ rotary table for this setup but you also need one for the main tube mitering fixture from Anvil.  The tube vise is around $100, a fraction the cost of other setups. Tube blocks from Paragon and a digital angle finder complete the package, and the latter two items you need anyways.  Granted, it’s not as nice and easy to get things perfectly in-phase as with a better fixture, but it’s pretty good. Check out this forum thread for some cool individual setups.

My Grizzly mill has a big table (9.5 x 32″) compared to some others in the price range ($1200) and that’s one reason I wanted this one – more room for dedicated tooling (not having to swap out too much).   On the message boards, ‘they’ try to scare you off of a round-column mill.  For framebuilding, it’s pretty much all you need IMO. Sure, it’s not nearly as rigid as a knee-mill or even a dovetail-column mill, but I’m not sure it needs to be to just notch tubes and do the occasional light machining. The round column means you have to re-center the X/Y when you raise or lower the head.  Maybe for milling this sucks, but I don’t find it annoying or necessary for what I’m using it for.  It shouldn’t need to be trammed every time you lower or raise the head. You can get away with not lowering the head as much if you use longer and shorter arbors (like those from Paragon), but the longer arbors do flex more and require a slower feed rate than if you were going to lower the head and use a shorter arbor.  Of course, you may need the longer arbor just for clearance reasons like with a seat-stay mitering fixture so the column doesn’t hit the fixture.

The only downside I’ve had is the inability (or extreme difficulty) in tramming the head to be perfectly perpendicular to the table.  It’s not perfect, but it’s damn close (a couple thousandths off – maybe). With small sheet metal shims you can position your work and get it close enough.  It sounds worse than it is.  Because I’m using not perfectly round hole saws on 0.6-1.2mm tubing that 0.002″ becomes moot.

Just like any tool, the more you learn about the trade, the more you realize what you would change about the tools you have.  This is one reason people say make your own tools.  I can see why one would do that, but you need tools and machines to make tools…so how do you know what you want in a tool or fixture if you’ve never used any before at length? Conundrum.

If I were to get another mill, i think it’d be a used horizontal mill instead of a vertical Bridgeport.  I’d love to be able to do unicrown forks and like the fixturing options of a horizontal mill better.  But maybe an old vertical mill with a right angle attachment would be just as good (?)…hmm. I really would like to have the horizontal option.

Even though this is a good mill, there are reasons this and other imported mills are cheaper. They have much more plastic all around instead of steel (handwheels, gib locks, belt drive housing). The cost of labor is the most obvious which why I’d rather support a US-made manufacturer if such a company still existed. It’s why there is and always will be such a good used market for old & used US-made milling machines. If you can find one, arrange relatively cheap and easy transport, fit it in your shop (height and weight may preclude some garages), I’d go that route for sure.  This Grizzly mill is not super heavy (555 lbs.) so i (alone) can move it with a half-ton engine lift into the back of my truck to move.  It rests on a cheap metal box, also bought through Grizzly, which works fine but vibrates and makes some annoying noises when running the machine.  It has built in storage, but I don’t use it, the latch is kinda lame. The mill needs a 20 amp outlet if you only have 110v power or 15amp if you have 220v, but is powerful at 2HP for a single phase machine. It’s belt-driven and easy to change belts and speeds vary from 150-3000 rpms. Since it’s belt driven though, there are only certain speeds you can get (150, 225, 255, 350, 400, 500, 850, 1200, 1500, 1600, 2300, 3000 RPMs).  I set it at the lowest setting of 150 for coping tubes, and speed it up to 400 to drill and slot.  It uses an R8 collet which is pretty standard; there is no stock power feed, it is completely manual but I think you can get a power feed attachment.

It’s pretty much a simple, reliable, big mill/drill that will likely last forever with what I’m doing with it.  I’m sure it could be more precise, more rigid, and more pleasing to the eye, but it does the job with very little file cleanup afterward each miter.

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