PDA

View Full Version : Hacker's guide to making EZ threaded connectors


bumpnstump
01-10-2016, 01:30 PM
DISCLAIMER:
One of the risks of sharing one's experience publicly, as on a forum, for example, is that what is shared may influence others to their harm. That is not my intent. My hope, in sharing about tapping and cutting aluminum, is that what I share will be an asset to those who read what I've written. What I share is what I've found to work for me. I hope that those more knowledgeable and/or experienced will chime in to better educate us; and, that all who read will do due diligence to do adequate research to their own satisfaction, so as to work safely. To that end, proceed at your own risk.

Making threaded EZ connectors.

First off: I am no expert. In my case, need dictated action, and this posting is an expression of how I go about cutting aluminum and then inserting threaded steel rods into that aluminum. I am hopeful that others will chime in with further tips, procedures, and experiences.

Secondly: safety is paramount. I've too easily hurt myself due to unsafe work practices. Please, don't do 'stupid'- take the time and effort to be safe.

Thirdly: have fun! If this is new to you, welcome- hopefully, there will be something of use to you. If this is 'old-hat' to others, please share your experience/insights with us.

Let's get going......

Pic one shows most of the items we will be needing:

-threadlocker to hold the threaded rod into the tapped aluminum;

-tap and dies. I am using 5/16-18 threaded rod, so that is the size tap I need. Each tap requires a specific sized pre-drilled hole. That information can be found online, or, it is usually listed on the shank of the tap. For 5/16-18, I need a 17/64 hole;

-marking utensils. Pencil and/or ink marker, as well as a punch, or, if you don't have a punch, a sharpened screw or nail;

-threaded rod, either from bolts, or pieces of threaded stock, or, if you're adventurous, you can make your own by using the die in your tap and die set;

-lubricant for tapping the aluminum. Whenever tapping something (wood, plastic, metal, whatever), it is usually recommended to use either a cutting agent, or, a lubricating agent. Aluminum has it's own 'preferences', and there are some great discussions online re. what is the best lubricant to use when tapping aluminum. Google 'best lubricant for tapping aluminum' and many discussions will appear. For aluminum, I usually use a penetrating fluid, like that shown in the pic, but have lately started using the paste wax- I like it.

-the EZ connector extrusion to be tapped. In the pic, you can see I've marked it out w/the pencil to be cut at about each 2"; the marker points (at the machined groove on the alum.) are where I want to drill and tap.

After laying out the cut and drill marks, indent the drill marks using the preferred punch- just a small dimple will suffice.

From there, I move the alum. to the drill press to drill at those punch marks. (Pic 2) The drill press allows me to drill precisely perpendicular thru the alum. If you don't have a drill press, pic 3 shows a simple wooden jig that allows you to achieve the perpendicular hole. Also in pic 2 is a chamfering bit. I begin drilling using the 1/8" bit, located in the punch marks. Then, I switch to the 17/64" bit, drilling, first from one side, half-way thru, then flipping the alum and drilling from that side till the bit goes completely thru. Finally, I use the chamfering bit to ream out the top edges of the drilled holes, ever so slightly. This gets rid of any rough edges on the alum, as well as providing a nice entrance ramp for the tapping operation. When tapping, I rub a bit of the wax on the tapping bit threads to lubricate them. To tap, I usually chuck the tap into my drill press, release the drive mechanism to the chuck (so that the chuck will turn freely by hand), and then, while levering the chuck w/the tap towards the hole in the alum, turn the chuck by hand to begin tapping the alum- I do not use the drill press under power. I continue till the alum is completely tapped. Notice, in pic 1, there are two taps: one is uninterrupted threads, the other has interrupted threads. If I use the interrupted-thread tap, I don't have to pause to clear alum chips out of the way while tapping- it is self clearing. W/the continuous-thread tap, you'll need to tap a bit, reverse the tap to clear the alum chips, continue tapping, more reversing to clear chips, etc. till you're completely thru the alum.

Once the aluminum is marked, drilled, and tapped, we can cut it to length. Pic 4 shows the alum partially cut by my miter saw. Alum can be cut w/a carbide saw blade, keeping these points in mind:

-clamp the alum. in place while cutting. Trust me- you're not strong enough to hold that alum completely stable while cutting; it will want to 'creep'. This can be dangerous.

-cut slowly.

-wear eye protection.

-I've found it safer to use a backing/spacer board like what's shown in the pic. so the cut piece of alum can fall freely away, once cut.

Pic 5 shows a finished threaded connector. Once the alum has been marked, drilled, tapped, and cut to length (2" is usually fine, unless you're making a custom jig), and, the threaded rod has also been cut to length (2" is fine for almost everything I've needed when using these threaded connectors), it's time to assemble. First, use the die (shown in the pic) to make sure the ends of the threaded rod don't have any deformation or burrs. Apply a bit of the threadlocker into the tapped hole, and onto the end of the threads. (Note: be sure to follow the directions provided by the threadlocker company.) Screw the threaded rod into the hole till it flushes with the bottom of the alum; wipe up any squeezed-out threadlocker. Set the assembly aside overnight till you are certain the threadlocker has cured. You're finished. Obviously, to use, slide them into a piece of EZ extrusion, place your wood or plastic or whatever over the threaded stud, and clamp down using a thru-threaded knob, or, a nut and washer.

HTH,
Rick

tomp913
01-10-2016, 02:54 PM
Nice write up Rick. I do it the same way pretty much, can't stress enough the need to make sure that the extrusion is securely clamped when cutting to length. I made a fixture for my old Sears 7-1/2" RAS (using Freud non-ferrous blade) that holds the extrusion in grooved plywood strips and then clamp the end with a toggle clamp. Luckily, I have a drill press so use that to drill and tap the aluminum - I highly recommend Tap Magic for aluminum, a bottle lasts a long time - and chamfer both ends of the drilled hole to minimize/eliminate burrs at the end of the tapped holes.

I have a little jig (no photo available at the moment) that I use for cutting threaded rod to length; picture a piece of 1" x 2" oak with a hole the same size as the threaded rod drilled through the 3/4" thickness near the end and a bandsawn slot across the width past the hole. Put a piece of threaded rod through the oak and tighten a nut on either side of the board. Clamp the board in a vise and follow the slot in the end of the board with a hacksaw, cutting the threaded rod between the nuts (obviously, you need to adjust the location of the rod/board/nuts to give you the required length of stud). Unscrewing the nuts over the cut ends of the threaded rod will straighten out any burrs from cutting and allow the end to be easily dressed up with a file.

Tom

bumpnstump
01-10-2016, 03:00 PM
Nice write up Rick. I do it the same way pretty much, can't stress enough the need to make sure that the extrusion is securely clamped when cutting to length. I made a fixture for my old Sears 7-1/2" RAS (using Freud non-ferrous blade) that holds the extrusion in grooved plywood strips and then clamp the end with a toggle clamp. Luckily, I have a drill press so use that to drill and tap the aluminum - I highly recommend Tap Magic for aluminum, a bottle lasts a long time - and chamfer both ends of the drilled hole to minimize/eliminate burrs at the end of the tapped holes.

I have a little jig (no photo available at the moment) that I use for cutting threaded rod to length; picture a piece of 1" x 2" oak with a hole the same size as the threaded rod drilled through the 3/4" thickness near the end and a bandsawn slot across the width past the hole. Put a piece of threaded rod through the oak and tighten a nut on either side of the board. Clamp the board in a vise and follow the slot in the end of the board with a hacksaw, cutting the threaded rod between the nuts (obviously, you need to adjust the location of the rod/board/nuts to give you the required length of stud). Unscrewing the nuts over the cut ends of the threaded rod will straighten out any burrs from cutting and allow the end to be easily dressed up with a file.

Tom

Love it!! Thanks for sharing, Tom; totally great stuff, as always.
r

Dik Harrison
01-10-2016, 06:45 PM
Great write-up Rick. I'm going to have to try paste wax the next time I tap aluminum.

bumpnstump
01-10-2016, 07:48 PM
Great write-up Rick. I'm going to have to try paste wax the next time I tap aluminum.

Thanks, Dik. Sometimes I wonder if I'm imagining things, but the paste wax does seem to work nicely. (Heck- if the 'pros', who do this for a living, recommend Crisco sometimes, no reason why the wax wouldn't be a comparable choice.)
Rick

tomp913
01-10-2016, 08:43 PM
Here's some back and forth re lube for tapping aluminum http://castboolits.gunloads.com/archive/index.php/t-76633.html I've used kerosene, but a machinist friend recommended Tap Magic for Aluminum and it works good. Never thought about Crisco, would have though that the chips would stick to the tap and be a PITA to remove. I have a ball of hard wax at the drill press that I used to lube the tip of the drill bit when drilling steel, just touch the surface of the wax to the tip of the spinning drill bit and it makes cutting much easier. For deep holes, I've taken a gob of Duck Seal, formed it into a "string" and made a dam around the hole that I squirt oil into to keep the drill lubricated. All kinds of tricks out there, some work better than others.

TooManyToys
01-10-2016, 10:20 PM
Good info guys. Something not well known is there are specialized tips for aluminum and brass but you have to go to an industrial source.

sean9c
01-10-2016, 10:32 PM
Cut your aluminum with your bandsaw. Wood cutting blade, dab of beeswax if you have it. Works great, saves you from making jigs and clamping things.

kenk
01-25-2016, 11:02 PM
Rick, I am proud to tell you that I am in the process of collecting the stuff to to dop my toe into the league of EZ hackers and make some connector clamps as you described. We'll see how it goes.

Ken K

bumpnstump
01-26-2016, 09:42 AM
Rick, I am proud to tell you that I am in the process of collecting the stuff to to dop my toe into the league of EZ hackers and make some connector clamps as you described. We'll see how it goes.

Ken K

Go, Ken! I'm guessing you'll find it's actually easier than it seems. Please post any tricks/tips you discover.
Rick

Dik Harrison
01-26-2016, 10:59 AM
Rick,

I tried the paste wax with taping aluminum, and it is great. Not as messy as oil. Thanks for the tip...

bumpnstump
01-26-2016, 11:21 AM
Rick,

I tried the paste wax with taping aluminum, and it is great. Not as messy as oil. Thanks for the tip...

Good to hear, Dik- glad it was an assist; we're all in this together, eh?

tomp913
05-01-2016, 12:48 PM
Revisiting an old thread - I needed to make some male knobs with longer threads for my adjustable height workbench. Here is a photo showing all the bits & pieces, including the piece of scrap wood with the through hole and slot for the hacksaw that I used for cutting the pieces of threaded rod to length.

aaronp
05-01-2016, 02:56 PM
Thanks for posting the all-thread cutting jig. New to me. I always just free handed it. I assume it will also help cut down on all the grinding and burr removal afterward.

tomp913
05-02-2016, 12:28 PM
That's the theory - the nut being unscrewed pushes any overhanging burrs to the end of the piece where it is much easier to file them smooth. If I did more cutting, I would perhaps look at one of the small (cheap) abrasive cut-off saws similar to those sold by HF. The set-up I use is quick, cheap(a big consideration) and gives good results - firmly clamped in a solid vise, a few strokes with a sharp hacksaw easily cuts the part and leaves minimal burring.