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ScottieB
09-11-2006, 06:53 PM
For all you machinist out there. I just procured a sqare column mill with x,y, and z DRO's. I do not know how to use this machine effectively.

For the basics, it has a R8 collet holder and I have a set of foughly 15 collets with it. I have a large table vise, and only one cutter that fits the collets. I have about 15 mill bits that are too large for the largest collet, which is 7/8. What kind of equipment do I need to use the larger bits?

Are there any web sites that deal in machining for the beginner. I have found CNCzone.com, but I have not found alot of info helpful. Are there any books that anyone would recommend?

Thanks for any help.

FriarTuck
09-11-2006, 07:01 PM
Hi Scott, try "The Home Machinists" here:

http://www.chaski.org/homemachinist/

Might find some help there, lots of good info.

Tuck

Tin Head
09-11-2006, 07:17 PM
Scottie,

You might also try lathemaster (http://www.lathemaster.com/). They carry tooling and cutters for smaller mills and lathes.

Bob

ScottieB
09-11-2006, 08:12 PM
Thanks to both Tuck and Tin Head. I will be spending alot of time over there for awhile.

Doug98105
09-11-2006, 08:40 PM
............

For the basics, it has a R8 collet holder and I have a set of foughly 15 collets with it. I have a large table vise, and only one cutter that fits the collets. I have about 15 mill bits that are too large for the largest collet, which is 7/8. What kind of equipment do I need to use the larger bits?

.............
Thanks for any help.

Think smaller on the cutters......even 7/8" is pretty big for an R8 collet system.

3/8 & 1/2" will be better choices of cutter sizes. Where you need to surface a larger area in one pass use a flycutter.

Doug

tdoty
09-11-2006, 08:59 PM
Indexable carbide endmills beat flycutters for a lot of things in my book. I bought mine off ebay for less than some people want for a "quality" end mill - 1" cutting face, R8 shank and 2 inserts. Could have bought a 1 1/4" 3-insert for the same price or a 1 1/2" for slightly more.

For end mills, check Enco. I bought a 10 piece set earlier this year for $27! Tooling comes in 2 varieties, and both are consumables. You have to weigh how much you'll be using it against how much it might be abused vs. how much it costs. With the industrial repair work I do, there are times the tooling is "abused", simply because it's difficult to be sure what you're going to cut into - might be a piece of cast iron that had a drill broken off in it 10 years ago, who knows. Hurts a bit less to break a tip off a $3 end mill than a $30 one. Once it's broke, is the $30 one worth more than the $3 one? By the same token, I keep my Putnams set aside for situations where I know what I'm cutting - virgin material mostly.

Big used end mills are pretty cheap, cuz the average guy doesn't have much use for them :grin: . Buy new stuff as your budget allows. I would say go with a budget end mill set from Enco to start with. If you wear them out (instead of breaking them), replace them with the better stuff.

HTH
Tim D.

ScottieB
09-12-2006, 11:01 AM
I bought the larger mills off ebay before I knew that I could not use them with my R8 collets. I was wanting to set up my mill for cutting tubing. The size of tube I usually use is 1 1/4. Enco has a free shipping sale until the 30th of this month. I shall take advantage of that. Thanks for the input, keep it coming.

ScottieB
09-12-2006, 11:23 AM
Also, if anybody can post pics of differnt type of cutters and what they are called, that would be a great help so I now what I'm looking for. ie shell mill and its holder.

rsanter
09-12-2006, 11:51 AM
scottie
using a mill is not that hard. there are a couple of things to think about when using one.
first it is like a big router or wood shaper. if you have any experience with woodworking the thought process is very similar in how you would appraoch something.
second, is the comment from karate kid. you need to picture in your head what you want and then remove everything else.
it helps to be able to see things meatally in three dimensions so you can see the part you want in the block you have.

the big difference between the wood and the metal is:
1 the metal part better be clamped in or clamped down very well
2 you will be removing less material slower with metal than with wood

bob

Doug98105
09-12-2006, 12:40 PM
Also, if anybody can post pics of differnt type of cutters and what they are called, that would be a great help so I now what I'm looking for. ie shell mill and its holder.

When you said square column mill I assumed desktop or slightly larger, exactly how big is your mill (table size, weight , etc)? Knowing more about your mill will allow us to give better advice.

You mentioned tubing, like in coping the ends? Rotobroach type cutters work well for that. They have 3/4" shanks so no problem holding in your collets. The Rotobroach brand is fairly expensive, KBC Tools sells a Polish made brand for a fraction of the price.

Doug

runner4404spd
09-12-2006, 01:47 PM
you don't want to use an endmill to cut tubing. will it work, yes, is it the best for your application? probably not. i would suggest using a hole saw to cut the tubing unless your justr trying to square the ends? i do alot of machining work and have a similar mill to yours. email me if you have any specific quesions and i'll try and help you out

JErry

jerry@superiordesignconcepts.com

ScottieB
09-12-2006, 07:40 PM
The mill weighs in a little over 900 lbs. The table is 39x9 with travels as x 30 y 12 and z 23".

Jerry, Doug, and Bob, thanks for the help. It's no wonder why I like this place.

godspeed
09-13-2006, 06:50 AM
Scottie,

Using bigger end mills is easy. You'll need to measure your shank size, and then you can buy an oversized holder for R8 (usually with two large set screws that hold the end mill in). Enco.com has them in cheap and American name brands. Also if you have a industrial surplus store near you, you can get tooling very cheap. I,ve have one close and tooling only costs about $.80 a pound! :grin:
As for large cutters keep the spindle speed slow for steel. Roughly 50 divided by twice the cutter size times 10 (old tool makers tip) i.e (50/(.5 dia. x2))x10=500rpm.
For aluminum just use 100 instead of 50. This will help you from dulling cutters.
IF you have a machine shop close, you can get a table of speed and feed rates from one of their manuals.
Ron

ScottieB
09-13-2006, 06:42 PM
Thanks Ron, I have no idea if I have a industrial surplus store in town. I'll have to do some checking on that. I need to start writing down this good info that I keep getting.