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View Full Version : Mussing about milling – a rather long post for a newbie.



Falcon67
07-08-2009, 04:23 PM
Especially long for a first post. A “this is my thinking because I don’t know any better yet, slap me into reality” type post. I'm a rank amateur in the machine hobby. But not too old to learn new tricks and not much afraid of anything. I own a 9x20 that I've been using to turn decent metal into scraps and making small things with. I don't have a machining background, but I have spent a lot of time in a past working life in QA/QC working directly with a capable machine shop. I wish I had taken more advantage of that opportunity when it was around - lots of good folks in that shop that would have shared knowledge gladly. I currently do networking, internet and wireless support at a 4 year university. I also own a HF micro mill that I've used for a couple of things, but mostly discovered that its way too small for anything I might really do around here. The plastic gears in it are a decent safety feature I think. I have used the mill to finish a mount for a 5” 4 jaw chuck that runs on the lathe, so I think the spark is there. I blew a transmission last year and was able to machine a new spacer plate for the high clutch pack that saved me bucks. I also make and sell fittings to let people use AN feed lines on Ford C4 automatics. I like to tinker and I like having stuff around that lets me solve problems, including the ones of my own making. Not production – just stuff. I build my own engines, transmissions, rears, etc for the race cars and like to be as independent as I can. I recently added an HF 4x6 bandsaw that beats the heck out of a hack saw. It cuts a little off the beam, but I’m still working on it. My wife remembers her dad had a machine (probably a ShopSmith) and he made a lot of candle sticks on it. So when I bought the lathe, she wanted to know if I was going to make some candle sticks. I scored 10’ of 1 ½” aluminum bar stock at the scrap yard, so I think I just might make her a set. :D I can tinker pretty good with wood – not cabinet work, but big stuff. I have a nice 20 x 24 shop that I built by hand with a hammer and a 9.2V B&D drill. I’m about to re-do our kitchen. Old houses require skills and I can match mess for mess with the best contractors, for sure.

I’d like to get better with metal. So I have this desire for a decent mill. Been doing a lot of research and reading, here and elsewhere. And spending too much time in the “reading room” with a Grizzly catalog. I really should be doing some real work. I’d also like to upsize to a 12 x 36 but the resident candle stick maker is working well for what I need. If I’d have known I’d have that much fun with it, I’d have gone for the bigger one. I scored the 9x20 for $500 on sale with a coupon so there’s no buyer’s remorse there.

First I got the hots for the HF 33686 and it’s sisters. Big table, not a wimpy machine, sure it has issues but I can work around or with those. Time is on my side. I could go get one quick if the local store stocked it, just waiting on the 20% coupon. The Griz looks nicer, and they have one with a handy X table feed that makes for a nice machine.

But for just a few hundred dollars more…

The G0484 square column caught my eye. That’s a big ‘un. Good looking machine, good price. Looks like one of the “RF45” mills. Not hardly enough space left in the shop for my own feet but I could park it next to a window so the table could slide outside on long X cuts. Square column, less Z axis issues, 18” under the spindle. Speeds seem a hair quick for tapping and too slow for aluminum but it’s a nice piece.

But if I stretched the budget (like there is one) to the very limit…

That G3616 is sweet. A real knee mill, higher speeds, footprint not too huge. Decent table, carries a lot of weigh. A little short on X travel and 15” under the spindle might make for creative setups at one time or another. .

So – what’s a boy to do. Either unit will do all the small stuff I can see doing around here, including flycutting pistons, bracket work, whatever. At the very top end of desires would be to do some work on cylinder heads. Surfacing, guide work, milling/tapping for studs and guideplates mainly. Maybe seat work, but I have access to a pro head guy and sometimes you are just money, time and performance ahead to buy expertise. Anybody can buy stones and mandrels. Doing at least some head work here would save $400~600 per pair easy. The typical head I use is cast iron, runs about 20 x 5.5 x 4 and weighs around 55 lbs. There is also the potential need to mill intake faces, but I’m not sure I can afford a mill with enough free space to do that. It is an operation that has not yet been needed around here. There are always brackets, spacers, gauge mounts, and general stuff. Something always comes up. Being able to make “it” is pretty dog-gone satisfying. But at my age I’ve also learned that half a loaf is better than none and maybe you just can’t afford to go everywhere you’d like. We don't like to go into hock very deep and we do use a credit card but pay it off every month. To get something decent, there will be some financing but it'll need to be kept short. And there's that space problem - already maintaining two race cars with a 20x24 shop that's has a big compressor, storage, lathe, big tool box, engine crane, several benches, drill press, chop saw, bandsaw, 10 ton press, MIG welder, etc, etc. Space is a premium. I have a nice oxy torch kit I bought on sale, but no room to park a big pair of tanks right now. If I manage a mill in the next year or so, something is going end up in the dog pen LOL.

When I think about the mills:
G0484
Plus - has the table size and travel, lower cost for a decent set of features, 18" under the spindle, lower initial cost leaves room sooner for things like VFD, DRO and other groovy acronyms.
Minus - is the table really thick enough to handle the load. Will it be able to hold .002 across 20” to surface a head – if it has the flexibility to do that at all. Speed set seems just a hair too fast for tapping and way slow for aluminum milling. I can always hand tap with the mill guiding.
Fixes? - three phase + VFD, assuming the internal gearing could handle higher speeds. Fix for a table issue seems like it would be "buy a bigger machine"

G3616
Plus - real knee mill, more mass, still affordable but at the limit, thick table (2 ½”) rated to 220lbs, wider speed selection, everything swivels, slides and turns so you can get it all out of tram in a hurry. Big swing, flexible.
Minus - 15" under spindle or less could be a problem with a head already 4” thick. Better speeds for aluminum but maybe not slow enough for machine tapping, short X travel (15")
Fixes – found pics of one apart on the web, could easily make riser for head if really needed to clear tooling. Speeds - again with the VFD + 3 phase or build an add on pulley system as seen in an older post here. Table - buy the G3617 table and X screw or try running in two directions, extending and swinging the head unit to cover a bit more ground – no cost if accuracy can be maintained.

And with either machine, if I can’t do all I’d like I can still do much, much more than I can now. Neither has a quill feed but I’m sure I can live with that. I’d rather have/make a DRO. Updates to the G0484 still don't run the price up too much. Updates to the G3616 cost more and would have to be put off, probably for the length of any note at least. I'm out of rich relatives - wait, there never were any. I'm not that interested in rebuilding an old machine tool – time is a premium along with space and there are none around here except big old oil field stuff thats been left outside since the bust in the 80s. And decent rebuildable units in the Dallas area are going to run $4500 and up anyway – outside the budget. I race with a guy that has been in the machine shop business for a long time and I will touch base with him. They just haven't been out at the track lately. I know the wish list screams “G9901” but that’s too far out unless that lotto ticket scores. I’d have to knock out a wall. Yes, I have looked at the IH mill but with table feed and shipping I’d spend over G3616 money. Griz shipping is cheaper than the trailer run to Springfield by $120 or so.

So any input would be appreciated. My “gut” says G3616. But is the low top speed on the G0484 (1512 RPM) a serious limit for working with aluminum? Can a hobby guy work around that? I would not like to drop $400 on a VFD setup on a G0484 only to have the thing eat its own gears at a higher speed. Does the desire to do larger work take it out of consideration altogether? Is the G3616 a decent machine or is it too compromised in small ways that might become big issues later on. I think only an experienced operator can help me think through potential issues – I just don’t know enough right now. Thanks for your time, consideration and expertise. Hopefully I can contribute something to the forum in return.

small.planes
07-08-2009, 06:03 PM
Welcome.
Im not in the US, so I cant comment on the actual machines, but someone will be along presently who can (usually anyway)...
A thing I found helpful when looking was to draw out the actual travels on a piece of hardboard or similar. then you'll quickly see if what you want to do will fit.
15 1/2" does sound very short (how long are the heads you want to do for instance, and then add on 2 widths to allow the flycutter/facemill to clear at the end of a pass).
I ended up catching a huge mill (49x11 IIRC, something like that anyway) on ebay, which meant the rally car had to go. (well actually the grinder meant the car had to go, but a smaller mill would have helped...:rolleyes: )

Dont forget to budget some for tooling, milling machines are more useful with:
collets, endmills, vice(s), clamping kits, RT, etc etc etc.

Dave

gnm109
07-08-2009, 07:01 PM
Neither of those machines has enough travel to handle larger work. The G0484 at 900+ pounds is lightweight and that can translate to flexibility, something to be avoided. I am informed that the gear head Grizzlys, Jets, Encos, and the like tend to have noisy gearboxes but I have no personal experience with these. I do have an ENCO 13 X 40 geared lathe that has done quite well in the past 15 years for me. It is not particularly noisy and is single phase.

Of the two, the G3616 seems a nicer machine with a better weight, yet only 15-1/2" longitudinal movement would be a deal-breaker for me.

Both are single phase and that can be an advantage for the home hobbyist on a budget yet there are advantages to three phase: lower current draw at given horsepower and synchronous (smoother) operation. The main disadvantage, of course, is the need for a source for three-phase power. If you get a machine with three phase, likely you would get a phase converter or a VFD to solve that problem like many of us have done.

If it were me, I'd keep looking for a used machine, either an American one or European or Taiwanese, something with a lot of movement and some beef to it. I looked for more than ten years for my present Webb (Bridgeport clone).

All of this is merely my own opinion however.

Good luck.

oldtiffie
07-08-2009, 07:34 PM
Thanks for that well constructed, very enlightening, balanced, well thought-out comprehensive post.

There aren't many of that quality presented here.

kmccubbin
07-08-2009, 11:18 PM
Welcome to the dark side... I'd recommend a 'real' mill. My interest in cars fueled my interest in machining. A few years ago, I finally saved enough money to buy a mill-drill, but couldn't figure out if it was really up to my expectations. I managed to buy a 9x42 Enco mill on eBay for $1100... in Lubbock. So there are machines in your neighborhood. I'm glad I held out for a full size machine. I rather doubt that a mill-drill would have enough working space for automotive jobs. And it's nice to not be pushing the limits of the machine each time I use it.

Kerry

tattoomike68
07-08-2009, 11:50 PM
I can see you using a mill drill to ream valve guides, counterbore valve relief on pistons, but not plane a head. I would farm out avanced machine work to folks who do it right and they dont use a turret mill. I could have used our 10 X 50 mill at work but knew it was a waste of time for me to mess with it.

One time I wanted to mill a head but the outfit down the road would do it for $50.00 pressure cheak and maginflux it. No way could i better that so I sent it to be done right and im sure most of you would do the same. When I saw the finnished work I knew I did the right thing.

Im not saying you cant plane a head on a mill drill its just not the right tool for the job.

you can have all the tools you want but at times its just best to send it out to be done right. in the same breath iv seen shops that plane heads with a belt sander, I would not let those bozos work on my lawnmower

Falcon67
07-09-2009, 12:58 AM
Thanks very much for the feedback. Scored a 9x42 in Lubbock, eh? IF I saw one for that price tomorrow, I couldn't get to the credit union fast enough. I'm trying to think ahead, big truck will be paid in several months so the urges will be harder to control as that time comes closer. And I'll keep looking at all options because you just never know. I've had my ear to the ground here for a while, nothing useful so far.

>which meant the rally car had to go.
I've had this race car for 35 years, they are burying me in it :D

>Dont forget to budget some for tooling, milling machines are
>more useful with:collets, endmills, vice(s), clamping kits, RT, etc etc etc.
That's a given for sure - machine is Capital Equipment, all that stuff is consumables. I have some end mills, small fly cutters and stuff. I'm about to buy a precision vice - it was on sale this afternoon at Enco for about 50% off with free shipping. Great deal, forgot to clear it with my wife, did so just now and use-enco.com say "try again later". I hope I didn't miss a deal - If I get it, I'll post details in case someone else wants one. Don't have the number in front of me. Some of the Griz machines come with an R8 collet set, if not it's still a must-have. I have a mill table on the 15" drill press (yep - I did, failed miserably as you'd expect) so I have a 1/2" clamp kit already, plus a Lilliputian set for the mini-mill.

>One time I wanted to mill a head but the outfit down the road would do
>it for $50.00 pressure cheak and maginflux it.
My guy would do it for free - but that's not the point LOL. I wanna do it, wanna learn, got plenty of junk heads I can practice on. I ain't skeerd of spending $500 on a $10 problem, heck I'm a drag racer - we do that all the time. :cool: But yes - he has a specific tool for that job that makes it a lot easier for him. It has a nice big head with about 8 cutters on it and it costs a bazillion dollars to have it sharpened or repaired. Plus shipping.

Which is also why I'm fishing for input - I still have all my digits because I try to respect the machines and not push them past their limits. Sometimes it takes a warning - the mill table on the drill press for example. Only takes a 5/8 chuck hopping out of the MT2 bore on the spindle at 2000 RPM once to get me thinking "hmmm, this is wrong". The table (and the 5" DP vice I scored at an auction for $5) is still handy as all get out - but not for milling anything. $85 wasted? Not at all because I learned something.

It is extremely helpful - and maybe life saving - to have someone say "yes, I see what you want to do and no, that item will not handle the task." Then it becomes easier in a way - you either step up the machinery or step down the wish list. I could do without surfacing my own heads, but I'd sure like to be able to mill and tap for rocker arm studs plus work the guides. I like to build 351 Clevelands (I'm a Ford guy) and they use a canted valve arrangement - tilted out and away from the cylinder for better breathing. On a small block Ford - like a Chevy- , one setup will cut all the pedestals. Not so on a Cleveland, there is a separate setup for both intake and exhaust. Twice the work, twice the price. Considerable DIY savings to be had there. And guide upgrades are not complicated, they just require some decent precision and proper alignment. Ream, press, ream or hone to clearance, next.

>Im not saying you cant plane a head on a mill drill its just not the right tool for the job.
Agree 100% If the right tool is not in my reach, I'll do something else. Overreaching can mean injury or at minimum ruined parts. No thanks.


>Of the two, the G3616 seems a nicer machine with a better weight,
> yet only 15-1/2" longitudinal movement would be a deal-breaker for me.

I keep coming back to that also. I would ask Griz service point blank if I could buy and use the table and lead screw from the G3617 on the G3616. the G3617 is the same machine with a horizontal milling addition. The table is larger and has 21 1/2" of travel. The manual is the same for both machines and the parts list shows both tables and both screws, and only one nut - so I feel sure they will interchange. The G3617 is only $400 more than the G3616, but it loses another 1" of spindle to table for some reason. You'd almost have to have a riser with that one. You can tell they are kinda pushing the 17 - the 16 is discounted but you have to pay shipping, the 17 has free shipping right now. So the 16 (right this minute) is $3150 and the 17 is $3395. Might even be a better deal than the 3616 for the price and features but my "newbie-ness" prevents me from seeing an advantage to having horizontal capabilities.

And it doesn't help that I know a little about speeds required but not enough to tell if the speeds available on these machines is "good enough" or "OK to start with but you'll have to replace the motor to make it really work well".

>Welcome to the dark side...
Hehehehe

Thanks again for the welcome and the opinions.

tmc_31
07-09-2009, 12:21 PM
My name is Tim McMurray,

I think we are real close to one another. I live in Quail Country (about 5 miles north of Tye. I have a small shop (20'X30') with a 1340 lathe and a RF31 mill. I too am new to machining. Have been messing with it for about a year as time permits. Give me call if you wish to talk machines, I will PM you my phone number.

Welcome to the forum. I have been a member here for about a year and have found it to be a pretty congenial group with lots of talent.

Tim

Falcon67
07-27-2009, 01:10 PM
The product of internet research (er, spending too much time with your face in the browser instead of working ) has led me here -

Part of "the answer" is about the envelope. The main things you have to work around is "what do you want to work on, how much space do you have, how much money you got". With that in mind, I've looked hard at the 6x26s, thought long about the G361x machines, left the specs for the G0484 laying on the bench and rubbed on a Bport 9x36 that I can bid on and guaranteed not to get because the owner is keeping it.

In the original post, I wanted to do some cylinder head work. A good hard look at that said "specialized equipment" - which I might get a line on later. Souix and Sunnen is where you want to be with that, really, to do it right. And a big mill will certainly surface a head - something I don't have space for. So take heads out of the mix.

Brackets, spacers, mounts, surfacing, misc "stuff" is what's left. I'm sure I'll think up more, always do. So that's a reasonable idea of what to work on.

Space - a premium, always. If I tear the shop apart, I might can find 6' of wall space, but it would be real difficult.

Money - I thought I had that covered with the last Lotto ticket I bought, but it turns out the state just ripped me off for $2. There are some changes coming that may negatively impact family finances in the next 6 months, so we're not getting into a long term note unless it's like $10 a month LOL. We could manage something over about 3-4 months tops. And nothing out of the kitchen fund, she's been too patient with my other crap. Prices tend to go up at the end of the year, and we don't have a lot of year left. I could borrow against the 401K - oops, last statement says it'll soon be borrowing from me.

None of the equipment I'm interested in is anywhere near here except the Bport, so it's hard to get a visual. Also seemingly a given - every machine until you get to the 9 x 42s begs for a 3 phase+VFD to get a bit wider speed range, either a bit slower or a bit faster. The round columns have the speed range and an excellent price point - but I'd pay a little more for better head control in the Z movement. A decent size table and a good size rotary should make up for most of what you can do with a swiveling head.

So I got some wood scraps and masking tape and mocked up the various tables, swings and spindle clearances on the bench and drill press. Nothing like simulation to get a better idea about things. Sticks and tape is all I have to help with the visuals. :) First thing I figured out by laying out table sizes on the bench with tape is "bigger table = more flexible setups". Shoot for the largest table you can get without knocking over the tool box.

And after review -

6x26 - a good unit, 20% coupon makes it under $1300 for the HF version. Perfect size for the shop, real knee. Bummer - Envelope feels just too small. My drill press has a 15" swing and we have had words in the past when trying to just punch holes in things. The 6x26 spec says it could be worse. The 6x26 has maybe just 1" more Y travel than the $89 mill table bolted to the drill press. Z is short but can be enhanced with a spacer, not that big a deal. No table drive but can be added for about $400. Unless you pay $3K for the Griz model. :eek: What in blazes makes that one so expensive? Little voice says "too small".

G361x - better envelope, knee, nice machine. Could use a riser for more Z, especially the 3617 if the specs are correct - fairly easy fix. No matter - cost outside budget. Lotto tickets are cheap and I get a Slurpee there too, so the door isn't completely locked. But we had to draw a line somewhere and this one is over it. Such is life.

G0484 - best price for features listed. At the very top of the budget. A ZX-45 in GrizGreen. Has power head, appeals to inner slacker. Enco version a bit cheaper web price but not enough to make up for the power head, stand and table drive. G0519 is the same mill and already has 3 phase motor, but add VFD plus table drive and you are in for another $500+. The VFD and motor can wait for a while. The 0484 has a decent work envelope and a nice big table. Not going to be as rigid as a knee but reviews of posts by other dovetail column owners says it's "good 'nuff". I can see doing some boring, but nothing super high precision so head movement doesn't strike me as a limitation. Table has more travel than I can easily accommodate - it will hit the tool box. First project - better handles :rolleyes: Speed is good for iron and steel, marginal for aluminum but will work. I don't run the 9x20 at anywhere near the SFM for aluminum and it's been OK. I already said I was lazy, why do you think I love my can't-cut-anything- square 4x6 bandsaw.

If the standard criteria of "buy the most mill you can afford" is applied, the G0484 appears to be the one.