Mill/Lathe

Chainreaction said:

You can kind of see the homemade mill through the bicycle frame. Bike frame was just simple basic frame for 6' 7" 300lb 50 something year old guy who had never ridden comfortably on a bike in his life. So I made him a big bike and finally he found bike riding fun. Still trying to learn mig weld with HF flux core.

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You absolutely keep an eye on that butt weld on the front down tube. It scares the crap outa me. Do you have a spud on the inside? If not I'd seriously consider welding half round patches on both sides of your weld joint.

Dan said:

Just ran across this. Take out the CNC aspect, make the chassis out of steel and use router as a motor and you have a DIY mill. http://www.instructables.com/id/My-Cheap-Handcrafted-CNC-Mill-Unfinished-Prototype/?ALLSTEPS

Wait, be easier to have a cross slide vice under. Would work awesome for small parts.

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That's pretty close to what my CNC router looks like, but mine is on a steel chassis... Mine uses a 1/2 hp motor on a flex shaft to the spindle and it can cut wood like butter and is capable of doing some soft metals, I've made a few copper exhaust gaskets with it to see if it would do it and it did the first 2 just fine but copper work hardens and it began to chatter badly on the third one I was cutting on the sheet. In order for me to do more of these I would have to cut the sheet down first, then anneal the pieces and cut out one or 2 at a time.

What's nice tho is I can get a better spindle motor like a pulse modulated DC motor so I can have the much needed torque at a very low rpm, then it would cut thru metals considerably better. I was looking at a 800 watt brushless dc spindle which would fit my mount and the price is still not that bad, but once you get above the 1.5 kw level with these motors and their driver circuits, that's where the price really jumps since the stronger motors are still rather small and require liquid cooling and a driver circuit that can take the additional power.

I was also thinking about using one of those brushless motors in the lathe since I could have triple the power and torque for close to the same size, these motors are pulse width modulated so that's how they can produce such awesome torque at lower rpm's, the power going in is the same, but it's modulated and it does it so smoothly you would never know the motor is going on/off several times a second to control the speed.

Flyman said:

Well I do not advocate using a drill press for milling.I think my post was taken
from context in that regard.I was implying that mills are used for much more
than just milling.When I said a drill press can be used as a mill I was talking
counter boring & such.

A good drill press with taper collets can be used with a boring head to bore
holes also.But drill chucks are just that, there made for drilling.So that's where I was going with this.

Fly

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It would have to be a real good drill press to have collets, like a Shipley. Then you could for sure use your drill press to mill but it seems like only the best old school machinist still have one and most have a K&T Horizontal Mill to go with a Bridgeport Vertical Mill so they are not needed for such use, a good thing. I'd hate to have to replace the bearings in a Shiply...

I do hope you guys have checked out the machinists I put up links for, especially Keith Fenners' and Adam Booth's videos. Keith is like having a machine instructor giving private lessons and Adam has a part he will have to do a weld build-up then turn the part back to size. What makes this different than any other weld build-up is it's done on the lathe with the part spinning....
He has a oxy/ acyt setup that introduces powdered metal into the flame making it like a plasma metal sprayer. I've seen him rebuild some badly grooved shafts with this device. He's the only guy on youtube that can do this. It's an amazing thing to watch.

Dan math is kinda like golf only different!

They both put me to sleep Greg.

I have to use math everytime I play golf, to keep up with how many balls I've lost! Sometimes I forget how to count,
(I don't cheat of anything I just "forget" a few that loose themselves.)

Dan That's the same way you install a flywheel ring gear, I was amazed the first time I changed one. I knocked the old one off and just heated the new gear with a aceteline torch, it dropped right on, then I tapped it down flush and let it cool.

Dan this might be cheating but all I do is adjust my digital calipers to 1.5 inches then hit the button that switches to mm.

DaveC said:

You absolutely keep an eye on that butt weld on the front down tube. It scares the crap outa me. Do you have a spud on the inside? If not I'd seriously consider welding half round patches on both sides of your weld joint.

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Are you talking about the welds part way down the front tube? Not to worry, one place was only partially cut and the other I slipped a piece of tube inside to weld to.

Dan said:

Chain, why didn't you like your router, DIY mill?

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Two major things. I have the drill press base nicely braced against the drill press post yet there is still a good bit of chatter up and down, on the order of .002-.006". The other thing is that it is really a pita to dial in my height. But it beats nothing and does an ok job of making slots if you dont mind cleaning them up.

Chainreaction said:

Are you talking about the welds part way down the front tube? Not to worry, one place was only partially cut and the other I slipped a piece of tube inside to weld to.

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"...slipped a tube inside..." That's a spud. Usually you want to drill some good sized holes in the outside tube then weld the inside tube to the outside. The spud then has like a "lug" that sticks out and keys the two parts together.

I was building a race car roll cage for one of my cars. Somehow even though I measured twice ended up being 4" short of meeting the floor at the right angle. I drilled 6 holes in both of the parts to be joined and hammered a turned machined spud in. I wanted it as tight as I could make it. When it went through tech I told them what I'd done, they inspected it closely and passed it. Backing broken tubing is common and as long as it's done right they will pass it. They could see the weld "rivet" heads, I didn't grind them down and try to hide, that for sure makes a weld weaker and makes a tech inspector really upset. They figure you're trying to hide something when you don't need to

But still, you check that after every ride like clockwork. It only takes seconds and it could save you major roadrash

Since most of the load is a pulling apart type it should be fine. If it had high side loads I might have went a little further. I like to sleep good at night so I try to do things in such a manner that I feel they won't fail. I have done things like taking out a load bearing wall on the ground floor of a two story house. Good eye you have though, most people wouldn't catch that or realize the potential danger.

How is Boise these days? I partied a number of times there years ago. I grew up outside of Grangeville ID down on a river called the Clearwater.

Chainreaction said:

Since most of the load is a pulling apart type it should be fine. If it had high side loads I might have went a little further. I like to sleep good at night so I try to do things in such a manner that I feel they won't fail. I have done things like taking out a load bearing wall on the ground floor of a two story house. Good eye you have though, most people wouldn't catch that or realize the potential danger.

How is Boise these days? I partied a number of times there years ago. I grew up outside of Grangeville ID down on a river called the Clearwater.

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In a word, wet I've been through Grangeville, we didn't stop though, on our way somewhere else, I think we fished some in the Clearwater on our way to some lake, can't remember what lake it was, too long ago.

Yeah, about the frame. I went on a short tour with a friend that ran a USAC Midget. it was part of my job for them paying my way to inspect the welds for cracks and use pliers to try and crush the aluminum plumbing fittings in the fuel system. Pure methanol eats aluminum like crazy and after a while turns into crumbly powdery garbage and you need to catch it before it breaks at 100 MPH... I found 2 small cracks after a unplanned exit into a rough infield. They weren't broken apart but we ground "V"'s in the crack and TIG them back good as new and kept on the tour. It was a madhouse torture tour, we raced 11 times in 3 weeks. Made money, won one Tony is a killer driver

Its funny but my lathe came with a big 4 jaw and never used it for a few years. My lathe set for a quit a few years before i bought it and slowly cleaned it up. Then one day i doug it out and glad i did. It is a 4 jaw with a sepperat ajuster that move all 4 jaws at the same time,then you can also move each one individually. Now i use it most of the time. Don't have a dial-indicator yet just set the cutting tool close untill it hits even.
What else is cool is it came with a drill chuck that screws on the spindle so i can use it to chuck small shafting up to 3/4"round stock. More acurate the 3 jaw ...........Curt