Self feeding saw?
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Joined: January 29, 2005
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Self feeding saw?
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Posted on Fri Mar 04, 2011 9:12 am
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Well, laziness is the mother of invention. And my hands hurt from feeding coils into a saw for hours on end. So I've decided to tackle the problem of having the tool feed the coil on its own.

Picture something like this, a pipeline layer,


but miniaturized, so it bolts on to the back of a Ringinator. Along with a small hopper, one could make oodles of coils, and then let it run on its own to cut them all automatically.

Would this be something people would be interested in buying if it was available for sale? No idea on a price yet, but it would be pricey, probably over $500. The servo and electronics alone will be around $150.
If there is interest I can design it with mass production in mind. Otherwise I'll just hack together something for personal use.


Make saw cut rings: http://www.Ringinator.com/

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Posted on Fri Mar 04, 2011 11:56 am
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Certainly interesting. I don't know If I would buy one, but it would be nice to see a prototype in action.

Joined: June 13, 2009
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Posted on Fri Mar 04, 2011 11:57 am
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Why so complicated?

I would think a rubber ram with a triangular notch driven by a threaded shaft through and adjustable channel on an incline into the Ringinator EZ would be an easier method. Much less for the customer to maintain and easy speed control. Just need a limit switch mechanism to cycle the ram back to the home position so it can be reloaded.



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Posted on Fri Mar 04, 2011 12:53 pm
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ive never used a ringinator (did narrowly lose an ebay auction for one a while back...) but i do wonder if gravity feed is an option?
or a pair of slotted wheels? you know, just some ideas, before a lot of time and money go into an unneccessarily complex design. just suggesting that all options be considered.

Joined: January 29, 2005
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Posted on Fri Mar 04, 2011 1:03 pm
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Yeah a ram was my first idea too. But coils don't like to stay rigid. When you put pressure on the end they like to buckle. To stop that you need to support them from all sides. My first plan was like a piece of conduit, with a motor pushing a long plunger-rod in the back, to push the coil forwards. However that would take up too much space and have slow cycles.

I use coils that are 3ft long or more, and all lengths in-between. This is doable for 1-2 sizes of coil, but I want something that will run any size with just the fiddling of a knob. (Same simple way fiddling 4 knobs lets the Ringinator cut any size coil). A ram setup also takes up a lot of space.

My basic plan right now is something that looks like the above, but with only one set of synchronous "wheels" feeding the coil (no treads). With non-moving supports on either side of the wheel to guide the coil down the groove. By adjusting the room between the two one would accommodate all sizes of coil.


Make saw cut rings: http://www.Ringinator.com/

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Posted on Fri Mar 04, 2011 3:24 pm
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Martin you and I think quite a bit alike... I have the basis of a design that would attach to the Ringinator with only minor adjustments.

I was thinking 4 air filled tires so you could change the amount of pressure on the coils being fed. Also it would just extend the V channel on top and bottom much like the Spring making machines I have been looking at.

Joined: March 12, 2003
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Posted on Fri Mar 04, 2011 4:35 pm
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a feeder belt. i've used those in extrution poerations. they work well for riddgid objects but i think you'll find that feeding a flexible opject is not as easy as you might think. that siad it still is better then a ram system. i could see that working for long coils of mid-large rings. still be at a loss for small rings or short coils. small "v" in the belt should hold it stable.

simplification is easy on these, think he is just using that pic as refrance of concept

Edit: i worked out a roller feed wheel at one time. it works for just about any coil. but is built in on the top of the saw, not as a attachment to it...
http://i70.photobucket.com/albums/i90/MaxumX/Maille/SawOne.jpg

you could replace the top wheel with your belt idea. and a stepper motor to drive it.


maille Code V2.0 T8.3 R6.4 Ep.f Fper Mfe.s Wsg$ Cpw$ G0.25-2.5 I0.5-30 N31.31 Pa Dacdjw Xa27g37w1 S94

Joined: December 19, 2009
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Posted on Sat Mar 05, 2011 1:59 am
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honestly i like the concept, but i do belive the application would just not be justified. there are many factors you have to take into account. just a few off the top of my head are, feed rates would have to be adjustable on the fly with some kind of force sencing thing. granted in a perfect world feed rates should be maintained acording to rpm and metal cutting, but things happen, coils bind and catch. there are just to many varialbes to take into account that a machine cant feel and adjust for reasonable priced. if the feed rate is to high, or to much force your going to just jam the coil into the blade endeing up in breaking a blade. to slow and the saw will dull faster. also make a "once size fits all" machine for this is just going to be a complete nightmare.


with all that said like i said i do see merit in the concept if you are looking at setting up a full fledged jump ring manufacturing shop were you plan on cutting 100's or 1000's of lbs daily.

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Posted on Sat Mar 05, 2011 2:21 am
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Dravin wrote:
feed rates would have to be adjustable on the fly with some kind of force sencing thing. granted in a perfect world feed rates should be maintained acording to rpm and metal cutting, but things happen, coils bind and catch. there are just to many varialbes to take into account that a machine cant feel and adjust for reasonable priced.


Generally speaking the only reason most binds happen is because of a slack in pressure on the coil. Having a constant feed would drastically eliminate that issue. Plus no one said anything about really setting the machine and leaving it. A simple variable speed motor would allow for control as needed.

Dravin wrote:
if the feed rate is to high, or to much force your going to just jam the coil into the blade endeing up in breaking a blade. to slow and the saw will dull faster. also make a "once size fits all" machine for this is just going to be a complete nightmare.


I disagree on the too slow and the blade dulls faster aspect. If you are using the correct lubricant to help cool the blade it can only get so cool. Last I checked having a blade spin without cutting anything didn't dull it.

One size fits all machine could pose a nightmare. However the one I am working on I have a machinist with an engineering degree at my work who is helping me with this one for fun. And he doesn't see it to be very difficult.

Dravin wrote:
with all that said like i said i do see merit in the concept if you are looking at setting up a full fledged jump ring manufacturing shop were you plan on cutting 100's or 1000's of lbs daily.


I would love to output that amount of rings per day. However at the current ability of feed rates I can only produce between 60-140 Lbs per day depending on the gauge of wire and the size of the ring. (obviously larger ID makes this even faster)

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Posted on Sat Mar 05, 2011 4:11 am
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Yeah, this whole design assumes you have a steady RPM hooked up to it. When I cut aluminum/copper I have it hooked up directly to a 1100rpm motor. At 1/2Hp no amount of pressure will slow that down. By hand I can feed about 1ft every 10 seconds. The problem is that it takes about 10lbs of constant pressure to feed the coil against the blade. Doing that by hand takes its toll quite quickly; 10lbs doesn't sound like a lot, but it is, especially when its all focused on 2-3 fingers clamping down on the coil.

The first iteration will be for aluminum/copper alloys. While it'll have enough oomph for stainless or titanium, I'd have to test it first.

The biggest reason coils bind is operator error. Even the slightest twisting action on a coil puts side pressure on the blade, and that causes the binding/breaking problems. A servo fed coil will not twist, it will be fed in straight, every time.

Using a servo and controller the feed rate should be easily controllable with a rheostat. And a decent servo will have plenty of torque to push any coil with sufficient power behind it. Pushing at a constant 10lbs of pressure works out to something like 50 in. lb. of torque, so quite a bit of power is needed.

Using a self feed system will allow the larger producers to use multiple machines per operator. Right now its one person feeding one machine. With the self feed it could be one person feeding several machines. Assuming 45 seconds to cut a full 3ft coil, 3 machines could be staggered 15secs apart, allowing one person to triple production. For 16g aluminum rings that means going from cutting a max of 25lb/hr/person to 75lb/hr/person. A significant increase that would pay for the upgrade in very little time.
15 seconds is also a long time. Grabbing a coil and feeding it into a tool takes more like 5-7 seconds. So depending on the operators speed, production can be increased up to 500%.

That's more rings than most people use in a year, but I know there are many people out there who go through that much material in a very short time.


Make saw cut rings: http://www.Ringinator.com/

Joined: December 19, 2009
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Location: Chippewa Falls, Wis

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Posted on Sat Mar 05, 2011 5:51 am
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ChainedReaction wrote:


I disagree on the too slow and the blade dulls faster aspect. If you are using the correct lubricant to help cool the blade it can only get so cool. Last I checked having a blade spin without cutting anything didn't dull it.


its a proven fact in the machining world that if the tool does not move through the material at the recommended feed rate the tool will dull faster. just having the coil sitting there and the tool moving, and not cutting it will dull faster, but the difference might be only a few percent of the blade life depending on the materiel.

but anyway lets just agree to disagree

Joined: December 19, 2009
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Posted on Sat Mar 05, 2011 6:02 am
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Martin wrote:
Yeah, this whole design assumes you have a steady RPM hooked up to it. When I cut aluminum/copper I have it hooked up directly to a 1100rpm motor. At 1/2Hp no amount of pressure will slow that down. By hand I can feed about 1ft every 10 seconds. The problem is that it takes about 10lbs of constant pressure to feed the coil against the blade. Doing that by hand takes its toll quite quickly; 10lbs doesn't sound like a lot, but it is, especially when its all focused on 2-3 fingers clamping down on the coil.

The first iteration will be for aluminum/copper alloys. While it'll have enough oomph for stainless or titanium, I'd have to test it first.

The biggest reason coils bind is operator error. Even the slightest twisting action on a coil puts side pressure on the blade, and that causes the binding/breaking problems. A servo fed coil will not twist, it will be fed in straight, every time.

Using a servo and controller the feed rate should be easily controllable with a rheostat. And a decent servo will have plenty of torque to push any coil with sufficient power behind it. Pushing at a constant 10lbs of pressure works out to something like 50 in. lb. of torque, so quite a bit of power is needed.

Using a self feed system will allow the larger producers to use multiple machines per operator. Right now its one person feeding one machine. With the self feed it could be one person feeding several machines. Assuming 45 seconds to cut a full 3ft coil, 3 machines could be staggered 15secs apart, allowing one person to triple production. For 16g aluminum rings that means going from cutting a max of 25lb/hr/person to 75lb/hr/person. A significant increase that would pay for the upgrade in very little time.
15 seconds is also a long time. Grabbing a coil and feeding it into a tool takes more like 5-7 seconds. So depending on the operators speed, production can be increased up to 500%.

That's more rings than most people use in a year, but I know there are many people out there who go through that much material in a very short time.


maybe instead of going with a servo and a controler, maybe think about going with a motor with some sort of break away clutch setup. this way you will get a constant force pushing on the coil. i'm also thinking of more like a wire feeder type set up might be ideal here, were you have one powered roller pushing on the coil, that rides on either 1 or 2 guide rollers. also with the clutch set up feeder rpm and speed would all be moot points. and also with some testing of course, it might work with the harder metals as well. with this sort of set up i could see i could see some type of magazine setup were all you would have to do is place all your same size coils into some kind of v shaped hopper and it should self feed.

Joined: March 12, 2003
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Posted on Sat Mar 05, 2011 7:19 am
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well i think somthing like this would work. (some parts not renderd, tightending screws variose manufacturing reduction items, eta)







if you allyed the right attachments to it.


maille Code V2.0 T8.3 R6.4 Ep.f Fper Mfe.s Wsg$ Cpw$ G0.25-2.5 I0.5-30 N31.31 Pa Dacdjw Xa27g37w1 S94

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Posted on Sat Mar 05, 2011 10:00 am
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Yeah, kinda, but without the belt. That could be a separate thing for a hopper though. That's a good idea. It wouldnt even need a lot of power, as all it has to do is move the coil in far enough for the drive mechanism to grab it. Something like those ribbed automotive timing belts turned inside out would would well.

Quote:

i'm also thinking of more like a wire feeder type set up might be ideal here, were you have one powered roller pushing on the coil, that rides on either 1 or 2 guide rollers.


Kinda. I was thinking more like this:



Using the circled portion, but with solid guides on either side. One drive wheel and one "free" wheel. The free wheel assembly would be adjusted by a screw/knob for different heights. If they are made out of metal with a hard rubber coating they will have enough friction to move the coils, and enough squishyness to adjust for slight coil imperfections.

The coil would ride snugly in the solid guides (like in a ringinator) and the rubber wheel would jut just slightly into that groove. Friction and mechanical force doing the actual moving.

Imagine a ringinator, but with a drive wheel instead of a blade, and instead of a plastic cover, another wheel on top to keep the pressure. Maybe with one of those one-way mechanisms, so it can only turn one direction. (the name eludes me atm)

Quote:
a motor with some sort of break away clutch setup


I have no idea how to build a clutch like that, or where to buy one small enough and cheap enough to work for something like this. However powerful servos are cheap and easy to find. Lots of DYI CNC retailers carry them, along with plenty of stock sizes of gears and drive mechanisms.

If it proves that 1 power wheel is not enough, then two could be linked together. Kinda like this:



Does it make sense?

If I get the design right, all parts will be mirrored across the tool, cutting down the machining costs to just a handful of parts that will be interchangeable. Maxums design is cool, but it would be expensive to machine that many different parts.


Make saw cut rings: http://www.Ringinator.com/

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Posted on Sat Mar 05, 2011 10:30 am
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more like this then?



my design there uses commen parts that you can buy. none of those rolles need to be machined. just buy some 3x3in puller wheels. guids are everyday 1in roller guids. the frame has to be fabricated, but that not much more then your EZ would require. and this would be a tool for more industrial use. so a little extra coast can be justified.


maille Code V2.0 T8.3 R6.4 Ep.f Fper Mfe.s Wsg$ Cpw$ G0.25-2.5 I0.5-30 N31.31 Pa Dacdjw Xa27g37w1 S94

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