I was thinking about over-boring, just also concerned that may weaken it, too. I’d need to think through this more.
I’ve seen annular cutters before, and have always wanted some for the metalworking quiver, but only have bi-metal hole saws currently. Thanks for the suggestion. That said, this project could probably justify a few or a small set if the price is right. I don’t have much metalworking experience, and am an entry level welder… lots of learning going on. So I don’t have a mill or a mag drill, but do have an old floor standing drill press, though the chuck stops at 5/8". Now, I think my friend who built his house may still have his mag drill, which I could probably borrow if it can be fastened to something that narrow.
Yes, I was thinking of equal leg length angle. I’m following you on the j-bolt and oversized nut pass-through.
Yeah, I’m probably overcomplicating that and have some background like that, but haven’t used it in a while. I was trying to calculate the moment of inertia of the combined angles (when bolted together), but it wasn’t quite working out. Does your gut and hands-on experience say the 1/8" 1-1/4" (or 1") may be rigid enough for purpose when panels are locked together, or you still think 3/16 is needed?
For the driveway enclosure, weight isn’t terribly important, if it’s up. But cost goes up a lot more going to 3/16 versus next length larger. Perhaps I even need to think about using some traditional fence panels (chain link… have a few rolls of that), with finer mesh attached to them.
Tomorrow or Wed, I’m going up near the place that sells steel at way less than locally (and also has a scrap yard at $0.50/lb), but I don’t think I’ll have it sorted out by then. Hoping, however, that I can find some plate for a welding table top.
I wish I could find that set online which was so inexpensive and was made for smaller chucks.
I did find a set and individual ones at drillsandcutters.com. Here is one which fits a 1/2" chuck and bores a 1" hole for $39. A lot more expensive than the set my brother bought but it’s essentially the same thing as an annular cutter.
Even if your friend has a piece of 3/8" plate steel you can mount the mag drill to that and set up a sort of drill press. Set a block of wood under where you are boring so the cutter goes through the metal and into the wood as a back stop.
You can use thinner plate steel at the base if you clamp more plate steel on top, so that you have a minimum of 3/8" plate stacked for the mag to grab onto.
Well…as you know everything flexes. Even a I-beam 2’ tall and 10’ long will flex some if someone stands on top of it. They just won’t feel it.
So it’s really how much flex you want to put up with. I think your 1-1/4" X 1/8" angle won’t flex to the point of failure by any means. I think if I was going to go with 1/8" angle, I’d probably go with 1-1/2" x 1/8".
As you know adding steel farther from the neutral axis generally makes it stronger than adding steel to the thickness. Again that’s the whole principle behind an I-beam (moving more steel away from the center, so that any flex in the center axis is more multiplied the farther away from the center it is).
That’s how me, a layman, wraps my mind around it. That’s why a 2 x 4 is stronger on it’s edge vs. laying it flat. I know engineers use terms like moment of inertia and modulus whatever, but I really don’t know what those terms mean.
Of course you can get some twist if the member is too tall and thin, but I don’t think you would see that with 1-1/2" X 1/8" angle. You will get some twist in the whole picture frame if you pick it up on one corner, but you’d get some of that no matter what, unless you added more bracing, or use a lot bigger angle iron.
All that said, for a project like this, I almost never buy new steel, unless it’s just absolutely necessary.
So you have the right idea going to a scrapyard to buy steel. Also look at Facebook marketplace or Craigslist. You won’t find the exact size and shape of steel you are looking for, but generally you can find something that will work for much cheaper than you could buy new. For example, you might find a good deal on square tube, or round tube. Then just figure out how to make it work in your design.
Sometimes you will have to weld some pieces together, but that’s pretty easy welding.
I don’t know if you own a welder or not, but if you don’t own one, you might consider a wire (mig) welder vs. a buzz box stick welder. A little 120v wire welder is a lot easier to weld with vs. a stick welder. You can use flux cored wire in your wire welder, so you don’t have to fool around with gas bottles. After watching a YouTube video, anyone could weld with a wire welder. It takes very little skill. Since it’s 120v, you plug a #12 extension cord into a regular 120v 20amp outlet and your off to the races. No extra wiring required.
For the minimum quality, I’d recommend a Hobart Handler. I’ve owned two of them. They aren’t as good quality as a Miller (even though Miller makes Hobart). Miller is the more professional line. But Hobart works good enough. If I need to weld something serious, I use my big welder.
Again, don’t be afraid to buy used, if the wire welder has very little use. A Hobart Handler 140 (what I use for light welding) runs about $700 new at Cyberweld (generally the cheapest online store I’ve found for welding supplies). But you could probably find a good used one on Facebook for 1/2 that. I’d caution against buying a super cheap mig welder at Home Depot, unless you plan only using it to weld sheet metal.
If you don’t want to spend that kind of money, you can get a good Lincoln or Miller buzz box used, for very little money. I just looked on Craiglist and found an old Lincoln asking price $100. They’d probably take less. Old buzz box welders are typically better than the new ones anyway. They used more copper in the old ones. And there’s not much to wear out on an old stick welder. Just the fan. If it’s a good old welder, they don’t even need a fan unless you are welding at something like 180 amps. But nobody welds with that many amps, unless you are building a ship. They do require a 240v outlet.
I bought my big stick welder used for 1/6th of the price of new and it included some extras. I’ve used it for 20 years with no trouble.
Anyway, probably more info than you wanted, but metalworking is the other thing I do besides fruit growing.
Here is a picture of a project I just finished for a guy on Sunday. I had to re-machine the top of the valve (the top was all screwed up) and make a delrin (i.e. plastic) washer with a counter bore. The valve was hardened 440c stainless steel and hard to machine.
I’m with you. I just have a few smaller step drill bits, so most of my drilling required changing out drills to get progressively larger holes. Took so much time. I’ve got boxes of large drills (literally) I need to sell on Ebay. I think some are up to 1-1/2" size, which is really more than my Bridgeport wants to turn.
Since I’ve started using annular cutters, it’s actually pleasurable to bore holes. And you get this nice little donut hole piece of steel left over. I save those little cutouts and use them for various things, like a spacers and things.
Thanks for taking the time to look and sharing those examples. I know I’ve seen some other ones that get used by electricians (greenlee, for example) that likely fit a 1/2" chuck, but don’t think they have the extended flutes like the ones you have. I’ve also seen those on craigslist, but unless very lightly used or unused, I’m not sure I’d know how to gauge their condition.
That said, I’d like to eventually own a mag drill. I haven’t looked into them much, but if they generally take 3/4" bits, I might as well buy those at 3/4" shank and pick up a larger Chinese knock-off chuck for the drill press.
I’ve been building up some stock of steel, and have some smaller 3/8" pieces. Probably have 500 lbs of steel laying around. Figuring out a wall mounted rack for that will be one of the forth coming project when I feel confident in my welds.
I had a 10’ stick of 1-1/2 x 1/8 angle in the garage, and just took it out, supported at both ends, and pressed in the center, parallel to one side. Really, barely any flex in that. Unless ultra tensioning the welded wire, I don’t think it would be an issue, and possibly 1-1/4" would work.
You’re absolutely right as to what you’ve explained, and usually that intuition as a experienced metalworker is so much more valuable than being able to theorize.
You might not care to know what those terms mean, but I’ll explain, in case you are interested. Young’s modulus just a constant for a given material that represents how stiff it is. At least, up to a certain working stress, at which the material starts to harden and eventually fail. So one number for plain carbon steel, another for aluminum. You just look it up and put it into an equation or calculator. Moment of inertia sounds complex, but just think of it as a cross sectional shape’s ability to resist bending. With those two variables, you can put them into a calculator (or equation), along with a desired load, and it will tell you how much deflection/bend something will have. You can find calculators that will tell you for a given shape (like angle) what that number should be, based on leg length and thickness.
For example, how much will 1-1/2" x 1/8" carbon steel that is 10’ long flex when I press 50 lbs in the center of it (you could also put loads as specific locations or distributed, but center would be ‘worst case’)?
Go to a calculator like this (you can calc it manually, too, but I haven’t done this stuff in 25 years, and anyone can use the calculator). Put in your angle information (1.5/1.5/0.125) and then select a direction you want to apply the load. For a equal leg angle, it doesn’t matter X or Y. Then put in a distance from the corner, where you want to see what happens when the load is applied. You could consider it at the corner (strongest) or say in the middle of the face where you attach a bolt for the tensioner. Let’s use the middle of the face, because this calculator will also give you the moment of inertia for the load at the corner (best, Ix0), at the tip of the angle (worst, Ix1), and at the desired location (Ix’). The diagram on this calculator makes it real nice.
Now you can go to a beam calculator of your choice for the load distribution. In this case, you’re basically considering it a beam that gets loaded, much like you mentioned before. Is the load in the center, distributed, or at one or multiple points, and is the beam supported at ends (most simple), cantilever, or at multiple points along the beam. Let’s use this calculator. Select Simply supported beam, Midspan Load. Fill in the fields Length (10’), Load (40lb as an example), Youngs Modulus value (200 GPa for A36 steel), and the moment of inertia you got in step 1 (0.1166 if loading 3/4" from the face or 0.1415 if loading at the corner). It will then tell you that the beam will deflect 0.43" and 0.35" [corrected] at the load. Keep in mind, for a 40lb load, that is absolute worst case (in the middle, of the beam and not distributed at all). If you shift the calculator to different loading conditions, you can see how it changes.
In this case it’s a scrap section at a steel distributor. They are right next to the steel yard, and get all their 2nds. Here, usually people on facebook/craigslist want way more than I can buy it new. For instance, people are selling angle for what works out to be $2/lb, and new it’s $1/lb. Sometimes, there is a deal, but 90% of the time people are wanting 1.5-2.5x what I can buy it for with a drive.
I’ve got a 210 MP (multi-process) welder, I bought a few years back used (with almost no use). I haven’t done very much with it yet, and have a lot to learn. I also picked up a tig torch and just last week an additional cylinder (Argon) so I can try some scratch start tig. I think in the long run, I may not need more of a mig welder than this, but will want to get a real tig machine to be able to do aluminum.
I’ve bought from there before. Also have gotten pretty good pricing at weldingsuppliesioc
I’ve thought about one of those… been years since I’ve done any stick, but plan to do some again.
That’s great. I’m hoping to learn a lot more, myself - both about fruit and metal working! Looks like you’re doing some real nice work, and having fun with it, too! Thanks for sharing.
I was thinking more about this tensioning, and it is definitely the most challenging part. If I didn’t want to through drill the steel, I could probably weld a bolt pointing towards the opposite side of the frame, and find some sort of a hook that can attach (and then tighten with nut). Not as straight forward as the J-hook you proposed, but less drilling. I have to chew on that one more… not sure it’s a good idea, and not sure about the hook for it.
Edit: corrected results for deflection example as I forgot to change my model from 50 to 40 lb load.
They look like 3/4" weldon shanks, but you could get this adapter for your drill press:
The adapter is made for a drill press because it has a 1/2" shank to fit a drill chuck. It has 3 flats ground on the shank, so it won’t spin in your chuck. I have something very similar for my mill, except it has an R8 shank for a mill.
You don’t have to use Hougen cutters in the adapters. They will accept any cutter with a 3/4" weldon shank.
I wouldn’t want to discourage anyone from buying a good tool like a mag drill, but they are somewhat of a specialized tool. They have few advantages of a good drill press (namely portability, and boring holes in large pieces of plate steel). They have some disadvantages to a good drill press (They don’t have an adjustable table (the table on a drill press moves up and down allowing for versatility of drilling various materials, and the table allows bolting down a vise to clamp small items.))
Most people who buy mag drills want them for portability or drilling plate steel.
The problem with drill presses is that most people own really cheap ones. I used to own a cheap one. It had lots of run-out and the slowest rpm was still pretty fast. But for a little more money, one can get a much better used drill press. There are lots of old ones if you look around and will turn a drill much slower. Old camelback drill presses are generally very good and not too much money.
I have a family member who owns a Clausing drill press which is very good. Powermatic is another good drill press. You just want a drill press which will allow a low rpm.
You also might consider a mill. They sell them pretty cheap at auctions. Here’s an auction in MN which has some really nice mills in it. It’s not hard to transport a mill with a trailer. I’ve done it. Or you can hire a rigger to transport. These mills are generally very good. Taken right out of production and have all kinds of extras (powerfeeds, Digital read outs, etc.) They typically sell for around 2K at auction.
It may not be in your budget now, but maybe something you think about before buying a mag drill.
Thanks for explaining Young’s modulus and moment of inertia, and the calculators. I’ve actually looked at Young’s modulus before, but honestly, I have a bit of a hard time understanding that vs. yield strength. They seem so closely related.
I see that on Facebook/Craigslist too. Plenty of people thinking their scrap steel is worth a fortune. But, sometimes there are good deals. Once I bought 3 ton of steel for $200. Almost all my projects are from scrap steel from Facebook/Craigslist or auctions.
One of my wooden fruit tables wore out, so I built a new one of steel (mostly) very recently. I think the original blue table frame cost me $15 at auction. The steel for the sides cost next to nothing. The treated plywood top was expensive. And it took some time to cut and weld the stuff together. You can see all the seams I welded. That’s because I almost always cobble together scraps of steel I have laying around.
I have it sitting against the fence out of the way because I need to re-gravel my parking area, and where my fruit stand is.
The table is unpainted, and ugly, by design. I’m afraid if I make it look pretty, someone will break in and steal it, and I need some good tables to sell my fruit.
You’ll notice my redneck engineering to keep the top and bottom from flexing/bending, lol. I stood on the top of the table and had someone watch as I jumped up and down on it. Pretty solid.
I am capable of making better looking equipment.
Here’s a YouTube video I made on a tire changer modification:
I’m a little embarrassed because the welds on that piece of equipment are crappy. I was going really fast because I didn’t want to pull the equipment out of plumb with a lot of heat on the welds.
Thanks for sharing that (shout out to @Audi_o_phile!)
The adapter is good to know about, and definitely like the flats.
First thought on use for a mag drill was as you describe, possibly drilling a handful of clamping/fixture holes in the welding table I’m starting to put together (on paper). As long as my friend has his, I’m happy not buying one yet! Realistically, there’s a bunch of other stuff that is more important first. I’ve been slowly accumulating some metalworking tools (5x6 bandsaw, nibbler, metal circular saw, clamps, etc) for a few years now and still have a lot of not quite ‘essential’, but really nice to have tools on the list. Now it’s time to start getting some projects rolling.
As to drill presses, mine is an old craftsman, shown here. Generally pretty good features/etc for a homeowner press (200-3650RPM, good table, etc). Problem with it is runout. My dial indicator is pretty crappy, and/or I don’t know how to measure runout well on a spindle (seems difficult with it trying to walk the tip away). I think I was measuring at the spindle, not arbor. Recently, I found my arbor/chuck interface is marred up, and hence the new chuck shown below. I’ll be interested to see if that has any impact on the runout.
I also have one of those porter cable drill presses, never used, that I picked up when a lowes location was closing down. It was one of their most popular presses, but seemed to also have not great runout, and the construction/table/burliness of it was just a notch down from the craftsman.
Now, a clausing or powermatic would be great, but more important upgrades first. A good drill press is definitely irreplaceable.
Mill would be awesome, and have drooled for a long time, but 1) no budget, as I’m rebuilding the house currently 2) definitely tight on space! We’ll see, once the house dust settles.
Think of it this way. Youngs modulus is just a material property that gives you a rule of thumb of how it will behave (think lengthen/bend) when you load it (psi), but only until you hit the load at yield point (yield strength). See the pic, below (from Wikipedia Stress-Strain curve page). Stress being the force over area (think psi), and strain being a measurement of the steel elongating for a given length of the steel.
Steel, below a certain load (known as the yield point) can see an infinite number of loadings and stick on that same straight line, moving up and down it. However, once you pass the yield point (where it’s no longer a straight, proportional line), the material starts to experience work hardening, and now it doesn’t follow that same line that shown on the diagram, rather it shifts to the right a bit. It’s slope (a.k.a Young’s modulus) may also change… I can’t recall for sure, but should. However, the point is that once your PSI exceeds the yield strength a single time, the material has permanently changed, albeit, getting harder (and likely less ductile). Continuing to add load beyond yield pt. as the crystals/molecules just start to slip by each other, eventually it gets weak enough (ultimate strength) that it won’t follow a lone back down to the 0 stress and this is the area labeled as 'necking. Eventually breaking. Bottom line, is design to use steel below it’s yield strength, and it will behave consistently and predictably over it’s use/life. Hopefully I remembered all that right. Does that help?
You can look up videos on pull tests. Doing a quick search, this video seems to show the correlation between the stress-strain curve and a pull test specimen. I only did a quick skim of the video, but think it may help (although fake voice).
Haha, yeah - for sure!
IMO, that’s a perfect looking farm stand table. What more could you want? If you put a nice looking table out there, people would accuse you of charging too much for your peaches, anyhow!
Thanks for sharing your project with those mods. Pretty cool! I wouldn’t be embarrassed… there’s a time and place for everything.
I went to the scrap area of the steel distributor yesterday… they get about 4 loads per year from the close-by mill, and unfortunately was too late to get some plate for a welding table top. However, I did pickup seven 2x2x3/16" tubular that was 77" long at $0.50/lb and will use that to build the base for a small welding table. Now I just have to come up with a design.
I picked up a few 10’ sections of 1-1/2x1/8" angle and 1-1/4x1/8" angle to do a little testing, but without really figuring it out first, didn’t want to buy more yet.
A few other tensioning ideas that entered my mind (not fully formulated yet) were 1… just letting the bolt pass-through the steel with an appropriately sized nut on the outside, and putting a little hole in the panel next to it. The nut would then act as a small spacer between the two panels. Not quite as rigid that way. Another thought was welding a series of loops/open nuts/fencing staples, etc) inside the angle, after which wire or stainless/metal zip ties could be used to tension it ‘good enough’, but I don’t think that is the best solution.
BTW, peach guru - any idea what eats baby peaches off my miniature peach, like this? <thread drift, warning>
I did some additional studying of the product that I sent privately to @Olpea and I have determined that the product listing must be indeed incorrect, that they and an almost identical product on the same website are actually 3/4 inch shank instead of the 1/2 inch claimed in the specifications.
Vevor is a funny company. Some of their stuff is really cheaply built, and some is decent value. I needed an impact for suspension work, but otherwise don’t need one often. I was stoked that one of theirs for about $60 did well on the torque test channel. For a tool that I’ll use once a year, I’m ok with the exception to buy once, cry once. However, some reviews for their stuff is quite bad.
Looks like they also make arbors that are MT2/Weldon 3/4"… I see a few in the $40-$50 range… If you can find an arbor with little runout, that might have potential to have less overall runout than chuck + adapter, but less versatile. However, I’m not sure I’d want to use an annular cutter in a hand-held.
At least it will go a pretty slow speed. That’s good. A lot of cheap drill presses will only go down to about 400 rpm.
Runout is a problem. A lot of times it is with the chuck or arbor. You should be able to get the tip of the dial indicator inside the spindle with a magnetic base (but of course you do need a good indicator).
On my mill the outside of the spindle was machined, so I just measured the runout on the outside before I bought it. Runout was 0.0002" which is the factory spec for a Bridgeport.
If you do have a little extra space in a corner, you can fit a mill there. They don’t take up too much space in a corner. And you can gain space by getting rid of your drill presses, once you have a mill
Your explanation of Youngs modulus and yield strength was excellent. I think I have it in my mind now. Thanks!
That’s some major catfacing. I’m guessing some kind of plant bug in CO. I’m not super familiar with insects in the western part of the U.S. I don’t think PC or stink bug would do that much damage.
Let’s hope my runout was from the chuck/arbor, since they are both being replaced. You make a good point on the spindle likely not having been machined on my DP. I’ll let you know what I find with the new chuck/arbor in place.
There’s always space for more tools
I have poked around on a mill, but the timing/money/space hasn’t been right yet. Your little bridgeport just tucks away in a corner? Haha. Seriously, though, I had never entertained the idea that a mill fully replaces a drillpress (perhaps unless a mill-drill). if I use the drill press for both wood and metal, do you think it does?
Oooh… catfacing. new term for me. The tree is so small I think I’ll get a fine mesh bag to put over it for the moment. I’m only the tiny tree put a couple peaches on, but 2 years in a row, probably removed near 100 peachlets. It does make pretty blossoms, though. I haven’t yet identified PC here, so if we have them, they’re very sparse. We do have stink bug, and many others, though overall low pest pressure.
For sure. Unless you have a honkin, big drill press (or a radial drill, which weight is generally messured in tons, not pounds) then a decent mill makes an excellent drill press.
Most mills (including Bridgeports) have an automatic downfeed for the quill. This is a feature most drill presses lack (except for large drill presses and radial drills). This is specifically for drilling. If you are drilling a lot of repeated holes, where you aren’t changing out the drill bit, you lock in the automatic down feed, and you don’t have to stand there and pull the hand lever to make the quill go down to bore the hole. There are 3 different settings to adjust the downfeed rate per revolution (0.0015", or 0.003", or 0.006" of downfeed per revolution)
Bridgeports also have a hand wheel for the quill downfeed, in addition to the quill downfeed lever. This is nice if you want more precise down feed. Here’s a picture:
Lastly, a mill will have the ability to turn a drill much slower. My Bridgeport can turn as slow as 60 rpms. Almost all mills have 3-phase motors. Most hobby machinists use a variable frequency drive (VFD) to convert their existing single phase electricity to 3-phase. The beauty of this is that you can slow the mill rpm even slower by reducing the hertz on the VFD. I’ve turned mine as slow as 10 rpm, when power tapping, just to make sure I don’t go too deep in a blind hole or something.
Lastly, the bearings are considerably beefier in a mill vs. a homeowner drill press. There are typically just a couple small bearings in a homeowner drill press. A mill has much larger bearings and there are lots of bearings in the bearing pack. Plus the bearings are much higher quality and have a pre-load (the cost of new spindle bearings for a Bridgeport is north of $400). This reduces runout to almost nothing. So yes, a mill is far and away a better drill press than a drill press, again, unless you are comparing it to a large drill press, or a radial drill.
Regarding using a mill as a drill press for wood. I’ve done that too. Just make sure you set something under the wood so you don’t drill into the table or vise. And set the quill stop at the depth you need.
You can also use a mill to “plane” down wood to some degree. Using a face mill (which is generally used to plane down metal) you can plane down wood. You just have to use aluminum inserts on the face mill when planing wood.
Mills are a very versatile machine tool.
I measured the distance from the corner to my mill to the furthest point out from the corner. It is 5’9". So basically the average arm span of a man if his fingers touched the corner and his arm was pointed toward the center of the room, that would be the furthest point the mill would come out in the room. That leaves plenty of room for the table to move on the X and Y axis without hitting either wall.
There is one guy on Youtube who even set a Bridgeport up in his basement. He has all kinds of introductory machining videos which are quite good.
So, you see, you have no excuse for not owning a mill because of space
