Seeking input on my first milling machine

[Cloudrepair]

No offense, but you're not understanding what he is trying to tell you. Think of a stationary point, in this case the end of the dial indicator under your quill. Now picture the table at an angle that is completely out of square to the head. The center point of the table remains stationary as does the quill. Now picture the table moving back and forth. All you are achieving is the verification that the table it flat. It tells you nothing about whether or not one side of the table is higher than the other. Might be fine for milling channels, but I could see issues with facing.


I've looked at lathes. But for that machine I will not compromise size and/or quality since my main intended use will be rifle barrels. It would have to be extremely precise and accommodate barrel lengths up to 30". I don't have the real estate in the garage for that right now.

My purposes for the mill right now are smaller parts and rifle stocks with softer materials like aluminum, wood, and delrin acetal. The smaller mill should do everything I need without any issues.

I hear you about the lathe and quality in some thing you can getaway with cheaper stuff in some it is worth it to get the best quality you can.
It was all just ment in fun

 

[Cloudrepair]

I just got a Taiwan lathe a couple years ago and the only way I got it was knowing what to look for.
I got lucky and found one that wasn't advertised as a taiwan unit but i recognised it as one and took a chance it was a 12x36

 

[ridgeway]

ok thanks for the input. i would be checking a spot under the quill for the whole length of table travel. thats the same as reaching out to the right or left. in fact its reaching out alot farther then 5 or 6 inches and so should increase accuracy. however i agree it isnt checking the rest of the table. can check the Y back and forth the same way. can do the same checks several different spots on the table which will tell me if the table is flat. it takes more time than most want to spend.

That is not tramming in a mill. WHen you tram in a head, the table stays put. Many ways to set up an indicator to tram, but basically you need to sweep the table 360 degrees with an indicator attached to the spindle. Once you get 2 spots in the X zeroed and 2 in the Y...that indicator needle should stay still when you sweep it 360 degrees.

Moving the table with an indicator stationary is simply going to show you any high spots on the table. If it moves, you got more issues than a head out.

 

[Ledd Slinger]

Again, I am no expert with a lathe, not even what you could really call a novice to be honest, but I do understand how they operate and I have played with them a little bit at work. I also understand that there is no such thing as a perfectly straight barrel. With that in mind, I feel that the 3 jaw chucks in some of the cheaper lathes are lacking. A 4 jaw or custom designed chuck with individually adjustable jaws takes more time to set up, but you can indicate a barrel properly in the chuck to eliminate runout caused by inconsistent concentricity. This of course is very important for cutting an accurate rifle chamber and single point threading the shank. Being that I am aware of these things and the barrel is the most critical part of a rifle in the accuracy equation, I cannot bring myself to compromise with a cheaper lathe.

 

[shortgrass]

That is not tramming in a mill. WHen you tram in a head, the table stays put. Many ways to set up an indicator to tram, but basically you need to sweep the table 360 degrees with an indicator attached to the spindle. Once you get 2 spots in the X zeroed and 2 in the Y...that indicator needle should stay still when you sweep it 360 degrees.

Moving the table with an indicator stationary is simply going to show you any high spots on the table. If it moves, you got more issues than a head out.

The only reason to sweep 360* if is the head will tilt forward and back. That PM will only tilt left and right. Some are fixed in that position as part of the frame casting, like my Index is, and are not adjustable. Gorton is like that too, on some of their models. My Index will only tilt left and right, no fore and aft. I have worked around some Gortons that had no head adjustment at all, always in a fixed position. Index and Gorton are probably both obsolete, although Index merged or was bought up by Wells and they're now known as Wells/Index. The "J Head", where the head will adjust fore and aft, and left & right, is part of what made Bridgeport famous, because of their adjustability. That PM, that LS bought, can be shimmed fore and aft if it is not true, 'cause the riser that holds the head is bolted on and not part of the frame casting. If you need to tram the head of a mill that is adjustable both directions (fore & aft, L & R) I would only work on one axis at a time, and then go back and check yourself.

 

[shortgrass]

Again, I am no expert with a lathe, not even what you could really call a novice to be honest, but I do understand how they operate and I have played with them a little bit at work. I also understand that there is no such thing as a perfectly straight barrel. With that in mind, I feel that the 3 jaw chucks in some of the cheaper lathes are lacking. A 4 jaw or custom designed chuck with individually adjustable jaws takes more time to set up, but you can indicate a barrel properly in the chuck to eliminate runout caused by inconsistent concentricity. This of course is very important for cutting an accurate rifle chamber and single point threading the shank. Being that I am aware of these things and the barrel is the most critical part of a rifle in the accuracy equation, I cannot bring myself to compromise with a cheaper lathe.

IMO, the chucks that come with most of those import lathes, that are so popular, leave a lot to be desired. That goes for both the 3 jaw and the 4 jaw chucks that are supplied as part of that "lathe package". For true "tool room" quality work a good chuck properly mounted on a back plate that has been trued and witness marked to the spindle nose that it will be used on is hard to beat. Good quality lathe chucks are expensive, but are often ignored by the hobby guys.

 

[shortgrass]

After the head is "dialed-in", then you can square the vise. If I need real precision, I put the soft jaws in and cut 'um. They'll be as straight as the table travels.

 

[Ledd Slinger]

IMO, the chucks that come with most of those import lathes, that are so popular, leave a lot to be desired. That goes for both the 3 jaw and the 4 jaw chucks that are supplied as part of that "lathe package". For true "tool room" quality work a good chuck properly mounted on a back plate that has been trued and witness marked to the spindle nose that it will be used on is hard to beat. Good quality lathe chucks are expensive, but are often ignored by the hobby guys.

Yeah Ive learned that the chuck and how it is set up is the most critical parts of the machine. Some of the best benchrest rifle builders in the world will usually build their own chucks. The resulting quality has proven itself on paper. It may be a long while before I acquire a proper lathe and learn the finer details of setup and proper operation, but I'm willing to makes sure I get it right. Nothing annoys me more than a badly machined barrel.

 

[hoz53]

The discussion is about 'squaring up' the tilt of the head, not flatness of the table. If the head has a tilt, it is NOT the same. The table on any decent mill is a ground surface, produced on a precision grinder. Think whatever you want, but in my 40+yrs of machining experience your method tells me absolutely nothing, only that you are measuring one point. The point is to tram the head to the table, so that the quill is an exact 90* to the table.

DUH ive known that all for 35 years anyway. you are not understanding me i guess. im not communicating well mabie. if you cant see how the method i described trams the head your 40 years of experience doesnt mean much.

 

[shortgrass]

DUH ive known that all for 35 years anyway. you are not understanding me i guess. im not communicating well mabie. if you cant see how the method i described trams the head your 40 years of experience doesnt mean much.

Hell! I can't help it if you've been wasting your time for 35yrs! The funny part is, no one else can see it your way either! Keep dreamin'!

 

[hoz53]

[QUOTE

Moving the table with an indicator stationary is simply going to show you any high spots on the table. If it moves, you got more issues than a head out.[/QUOTE]

thanks for that info


there can be more reasons the indicator might move than high spots in the table. like mabie the head is tilted. using the sweep method you describe you could be indicating high or low spots to. i just know the method i descrilbed works for me and gets my table to quill more square than the tramming method you describe and i know alot of people use. ive tried both. my only reason for posting in threads like this is to try to help someone and im sorry if ive provided info that appears to some to be wrong. thats the last thing i want to do so i wont post answers to posts anymore. thanks again

 

[butchlambert]

Shortgrass is correct. Go to http://edgetechnologyproducts.com/ and look at
Pro Tram System 01-000, 10-000, 09-000 Might be over kill, but I like it.

 

[ridgeway]

You can tilt the head 45 degrees, stick the indicator on the table and move the table across and it will measure the same thing.

I'm not saying what you are doing is wrong...just not understanding how that makes the spindle perpendicular to table? Maybe I'm not reading it right.

The sweep method is how a head is trammed. Not my method...it's how it's done.

 

[Dusty Stevens]

I thought a mill was the only thing that can reproduce itself- in all my years ive never seen how you could make a tailstock or a cross slide on a lathe but i could make a table on a mill. Not sure what i know anymore

 

[ridgeway]

Shortgrass is correct. Go to http://edgetechnologyproducts.com/ and look at
Pro Tram System 01-000, 10-000, 09-000 Might be over kill, but I like it.

That's too fancy for me. Idicol and Interapid works for me, lol

 

[Ledd Slinger]

Shortgrass is correct. Go to http://edgetechnologyproducts.com/ and look at
Pro Tram System 01-000, 10-000, 09-000 Might be over kill, but I like it.

That's one of the items I ordered. The .0005" model is on the way with some of their other products. All appear to be very nice quality. Can't wait to see how they work out.

My plan is to have the Pro Tram in the shank measuring Y axis while I have their clamping indicator arm (43-000) mounted on the spindle with a Swiss dovetail gauge to sweep the X axis. This will allow me to measure 2 points of Y axis at the same time I'm sweeping each side of X

 

[Dusty Stevens]

You can tilt the head 45 degrees, stick the indicator on the table and move the table across and it will measure the same thing.

I'm not saying what you are doing is wrong...just not understanding how that makes the spindle perpendicular to table? Maybe I'm not reading it right.

The sweep method is how a head is trammed. Not my method...it's how it's done.

Sweeping a mill in with that method has been the standard since the beginning of time i thought. The tool i posted a link to is usually the first tool used on a mill the day its set up. Sweeping 360deg will tell you everything you need to know- if the head is tilted back, sideways, and moving the table will get the vise straight and level. One lil ole $19 tool with an indicator you probably already have. Then you put a stock in there and see how straight the sides are, level it to inlet.... its an indespensable tool for me

 

[hogpatrol]

Dang I love these discussions. Now for a moment of levity.

I'm teaching machine shop practicum, students are working on their projects, I'm sitting at the desk doing some computer paperwork. A student comes to me and says his Bridgeport is tilting over, looks like it's about ready to fall. WTF??? I walk over, the mill is tilting left at about fifteen to twenty degrees. Holy crap! How is that possible? I look down and he has a chair jammed under the rapid traverse motor under the right end and as he was lowering the table, and not paying attention, the chair jammed and was forcing the mill to tilt. I grab the handle and gently raise the table, the mill goes back to the floor and all is well. Since he was on the short side, he had been using the chair to stand on to reach the drawbar. We renamed that machine the Leaning Bridgeport of Practicum. I won't name names but that student is now racing a pro stock motorcycle in the NHRA Mello Yello series.

We now return this thread to your regular programming.

 

[Alex Wheeler]

I am in the market for a mill and have been doing a TON of research. Starting this thread to further my knowledge with your opinions and wisdom. I only want something big enough to open barrel channels and machine soft metals and polymers or make small cuts passes on SS/carbon steel. Basically I don't want to deal with a 3,000+ lb machine. Trying to keep it around 400 lb or less with a 1-2 HP spindle motor. No plans on being a gunsmith. Just want to be able to make certain things for rifle accessories and do a little stock inletting when needed.

Been looking at some of the more affordable models like Grizzly, Jet and Bolton Tools mills. Seems like they will keep tight enough tolerances for rifle stock work and machining small insignificant rifle accessory parts. Been mainly eyeballing the Grizzly G0759 with DRO. Has enough X axis travel to open a barrel channel and enough power to work on a little bit of metal with the right tooling while maintaining a fairly small footprint and light weight.

Willing to consider other machines from your input, but am not sure how much money I want to spend because I don't really have experience with mills, which leaves me unsure about what I will need/prefer. The use of a good DRO on X,Y,Z seems to be a unanimous consensus in my research. Power feed on the X axis is highly recommended as well. I have a large industrial high precision vertical mill and lathe at work, but haven't got around to using them much yet. Plan on playing around with both in the near future making random parts just to get a feel for things.

So again, I'm just looking for a good hobbyist mill that won't require a forklift and chain blocks to move or take up a whole quadrant of my 2 car garage. Thanks guys.

I recommend keeping your fingers away from that sharp spinning thing. Hope that helps

 

[Cloudrepair]

I thought a mill was the only thing that can reproduce itself- in all my years ive never seen how you could make a tailstock or a cross slide on a lathe but i could make a table on a mill. Not sure what i know anymore

The mill I run nowadays maybe with at least a 4th axis a 5th would be good to.
Haven't you ever maid square parts out of round parts on a lathe or bored a offset hole in a square part on a lathe