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Kaejo

market for a saw cutting rig

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I came across a 1/8 hp single phase a/c motor that runs at 1050 rpm from a friend, came out a heater I think.

I started out thinking about pulleys to adjust the speed to cut steel but thought I could do it much easier with a Router Speed Control from harbor freight for like $20, motor shaft arbor and drill chuck for $15, and my own saw arbor(s) and a little umhw.

IF the speed control would work with this motor, wouldn't that be a more stable (no gears and shafts to wobble) and cheaper way to do it?

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&$%@#! nevermind...

A speed control won't work with an induction motor, only universal brush-type motors, which run at about 6-10,000 rpm.

Well this motor would be perfect for cutting Aluminum with a 2" blade, I'll just use it for that and dream about a pulley system for steel.

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update on progress. The motor is going to be what really determines the cost. Variable speed motors are more expensive than single speed generally. I'm going to try and find a variable speed motor that will work and keep my costs down, but if I can't, for those of you that are interested, would you rather spend more on a single machine (up to about $700), or pay a lot less ($300 or so), but have to buy one machine for soft metals and another for harder metals? (I'm not even sure if that will work, I'm just wanting to get opinions before I spend alot of time on the idea)

Disclaimer, the prices listed above are not final, just educated guesses.

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update on progress. The motor is going to be what really determines the cost. Variable speed motors are more expensive than single speed generally.

You can't implement some kind of PWM to vary the speed? Even just a TRIAC or a light dimmer, or a more expensive light dimmer designed for inductive loads?

I'm going to try and find a variable speed motor that will work and keep my costs down, but if I can't, for those of you that are interested, would you rather spend more on a single machine (up to about $700), or pay a lot less ($300 or so)

Amazing how easy everything sounds, until you try to do it yourself, huh? :P Suddenly up, up, up, up, up go the costs a little here, a little there.. and now you're maybe the most expensive option on the market!

Whenever I get an idea in my head and think "Why don't they just...", I first try to make sure I understand why people do things the way they already do them. Somehow defying the principle that most people are idiots, is evidence that most products aren't actually crap, and are somewhat decently thought-out.

Look at drill presses. People often want to vary the speed of their drill.. why go through the rigmarole of pulleys you have to manually change? Why not just variable speed motors? Probably because it's the most cost-effective way to solve that problem.

Though.. if you're looking at a motor that's $400 more expensive in one variant than the other, and the motor being the major cost, (as much as $500 for a motor or so then?), you're paying way too much.

If someone can sell a Drill Press for $60, all included, or buy a lathe for a few hundred, no way you should be paying several hundred for a motor, even a sizable one.

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I was having a similar thought this morning. Previous attempts at this (such as the MKII) have used drills... I can go to home depot and get a variable speed drill for $30. Now, I understand that they have the advantage of being able to make their own motor in bulk... but there has to be a less expensive option.

And I think you're right, some of the cost has been in making it variable speed. If you go to the places where you buy DC motors, the controlers they have are computerized and I don't see any reason why a simple dimmer wouldn't work.

Based on exactly these thoughts, I think I may have been able to reduce cost significantly. I'll have to talk to my machine guy to be sure though.

Edited by Shadowkin
afterthought

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I have been looking around at motors and depending on the hp requirement wouldn't this DC motor (second on the page) be appropriate? runs for about $100

I know the description doesn't say its minimum rpm but you could use a simple gearbox to reduce rpm (maybe $30 for some gears plus some extra fabrication)

Using this type of motor would work because the torque increases as speed decreases.

Comes with controller and motor.

I am designing/building a direct drive sawing rig at the moment for personal use...being the son of a machinist and an engineer and machinist myself doesn't hurt either...

Edited by affinityofmist
fixed link

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I have a bit of an issue with it being an ebay store. If I were only looking to build for personal use, that would be fine. But looking to manufacture a product, having their only storefront be ebay does not instill confidence that they will be around long.

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I'm not buying it...I have a motor that I am using...but I stumbled upon it in my search a while back when I was looking for a motor...just thought I would throw it out there and see if you have looked into anything like that.

but all in all...if you can set up something for ~$250 as a one time purchase that will do any coil size in any metal it will be marketable...it's all the extras that people may have to buy to get it to work for their size/material that give me second thoughts...

Edited by affinityofmist
grammar

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I have been looking around at motors and depending on the hp requirement wouldn't this DC motor (second on the page) be appropriate? runs for about $100

1/8 Hp sounds good. It might be a tad light for the big stuff, but.. not too shabby.

I love those motors. They're basically auto-geared. Rather than losing torque along with speed like many controllers, or, barely maintaining torque while dropping speed, when one goes down the other goes up.

Even that's expensive for such a small motor, but considering it's speed adjusted, not bad at all.

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I'm not buying it...I have a motor that I am using...but I stumbled upon it in my search a while back when I was looking for a motor...just thought I would throw it out there and see if you have looked into anything like that.

but all in all...if you can set up something for ~$250 as a one time purchase that will do any coil size in any metal it will be marketable...it's all the extras that people may have to buy to get it to work for their size/material that give me second thoughts...

not as bad as it sounds. 2 kits one of which would come with the machine. one for armor, one for jewelry. Maybe I'll put together a package that includes both at a slight discount.

Edited by Shadowkin
typo

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ok, I'm running into a little bit of a snag and I'm hoping you guys can help me out. I know that with the 1.25" diameter blades that are sold here, harder metals need to be cut at less than 500 rpm, but does anyone know what the optimal speed is for softer metals?

Oh, and I wanted to say thanks to affinity. I looked a little more closely at that company and they seem more reputable than I would have expected from an ebay store. I'm not sure if that particular motor will work, (motors don't seem to be my shop guy's area of expertice, but he seems convinced that there won't be enough power at the lower speed required for stainless and such) but they do custom motors too. I sent them an email and am awaiting a response.

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Ok, I finally have my design about done and ready for a prototype. It does look like it's going to be a little more expensive than the MKII, but I think the quality of the product will make it worthwhile.

Also, I managed to get it done so that the whole seperate kits thing won't be needed and it'll do anything from 12Ga 3/8th ID down to xGa 3/32 ID (I have to test Ga on the small end to see what I can do without mangling the rings)

It'll be self lubricating and easy to use, have a real motor with a variable speed control. and take just a little over 2'x1' of bench space.

The prototype is still probably a couple weeks off and of course I need to do some testing and work on protecting my IP. But as soon as I think it's ready for production I'll talk to TRL about sending them a test unit and if they like it, selling it here.

Speaking of which, does anyone have a picture of the original AMS. Some of what I've heard about it sounds similar to what I'm doing and I want to make sure I'm disclosing all relevant prior art when going for a patent.

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Hey everyone. I don't know if this is of any help or not since I've only used it to cut aluminum but I took a coil of alumimun to have it anodized. Meanwhile I made this little platform for my dremel to cut the coil. All it was was a piece of soft wood 1"x2" cut down to a couple of inches. Using my drill press I made a hole the same diameter as the coil I was cutting down the middle of the 2" length part, this way the coil passes right through snuggly. I made a cut on the top just wide enough for my blade to fit into, the blade was purchased from Mcmasters I think it was. I attached this piece of wood down to another board where I was able to clamp the dremel down to keep it from moving around. You have to make sure you clamp the dremel down on the correct side, you want the teeth to cut from within the coil, so once it's cut it falls down to a bin below. If you have it cutting from the top then the tooth will catch it and shoot it up into the air. Once you turn on the dremel just push the coil through the hole. I used T9 as lubricant because I had no lub on hand to keep the blade cool. Once you reach the end I used a wooden dowl to help me push the coil the rest of the way. I did like 6 coils like this in a matter of minutes and got beautiful clean cuts. If you would like I'll try to post a picture of the rig, I think I left it here in the warehouse somewhere. Only cost a couple of bucks to make since I had most of the materials.

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Interesting thread here. I may have a bit of an overkill solution for myself. I just started the Chainmail stuff but Ive been metalworking in general for a while.

Ive got a bridgeport milling machine that with a couple of small fixtures would make a real nice coil cutter

Bridgeport1-1.jpg

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Hey everyone. I don't know if this is of any help or not since I've only used it to cut aluminum but I took a coil of alumimun to have it anodized. Meanwhile I made this little platform for my dremel to cut the coil. All it was was a piece of soft wood 1"x2" cut down to a couple of inches. Using my drill press I made a hole the same diameter as the coil I was cutting down the middle of the 2" length part, this way the coil passes right through snuggly. I made a cut on the top just wide enough for my blade to fit into, the blade was purchased from Mcmasters I think it was. I attached this piece of wood down to another board where I was able to clamp the dremel down to keep it from moving around. You have to make sure you clamp the dremel down on the correct side, you want the teeth to cut from within the coil, so once it's cut it falls down to a bin below. If you have it cutting from the top then the tooth will catch it and shoot it up into the air. Once you turn on the dremel just push the coil through the hole. I used T9 as lubricant because I had no lub on hand to keep the blade cool. Once you reach the end I used a wooden dowl to help me push the coil the rest of the way. I did like 6 coils like this in a matter of minutes and got beautiful clean cuts. If you would like I'll try to post a picture of the rig, I think I left it here in the warehouse somewhere. Only cost a couple of bucks to make since I had most of the materials.

There are a few problems with what you're describing, but it's not bad for a homebuilt rig. The biggest problem with it is that is that a dremel spins too fast to cut harder metals.

I started working on this because machine cut just doesn't cut it for me anymore (pun intended) and saw cut is either time consuming or expensive unless you have something like this set up. But there are some issues with the current rigs for sale and I felt there had to be a better way. One of the issues is that I can't justify spending $400+ dollars for something that looks put together at home depot. Another being that lubricating the blade wasn't handled well. And finally, it seems that the ones that do handle harder metals are never in stock. I had thought to just make one for myself, but I figure if I can solve these problems, there are others that would like one too.

A lot of time and thought has gone into this and I think those people that aren't interested in engineering their own rig and want the quality of saw cut rings are really going to like it. And if not... well at least I've got one for myself :D

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Interesting thread here. I may have a bit of an overkill solution for myself. I just started the Chainmail stuff but Ive been metalworking in general for a while.

Ive got a bridgeport milling machine that with a couple of small fixtures would make a real nice coil cutter

Bridgeport1-1.jpg

heh, yeah, you could probably put something together with that... but I'm going for something a little smaller and I'm guessing less expensive :D

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heh, yeah, you could probably put something together with that... but I'm going for something a little smaller and I'm guessing less expensive :D

Seriously though, if you guys need something made up, milled/drilled or whatever, Ill be glad to help.

For a good cause I may work really cheap to free:cool:

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For a good cause I may work really cheap to free:cool:

Sold. For the price of Free.

Maybe I can talk you into machining a few spot welder ring cradles hrm? :P

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I have the potential of sufficient income in the near future, and am interested in trying one of the devices when they are ready.

Now that I have the money for the table saw I needed to make Harmony's coil feed guide, I have forgotten how to make it, as well as where I put the link. -_-

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Hello Shadowkin do you have pictures

I have a ring cutter - it is a pepe tool and it is OK.

But If I decide to get into this seriously I would like something

'More Professional' as you said earlier.

I would be interested in updates as your design progresses.

Aaron -beginner

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I have some drawings at this point but I'm not releasing them untill they are pattent pending. Unforunately, I'm at a bit of a hold up because the machine guy needs 3d drawings of the parts that need to be machined and my CAD guy is estimating an additional $600-1200 to do that which means I either need to come up with that myself, or get it from an investor. I have someone that has already invested some, but they aren't going to want to invest further without a business plan, and in order to do that I need a quote from the machine shop. It's a vicious circle.

At this rate, we are likely looking at public release in January.

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Originally Posted by Shadowkin

...Unforunately, I'm at a bit of a hold up because the machine guy needs 3d drawings of the parts that need to be machined...

Any machinist I know, (and I know quite a few) are able to make parts from regular 3 view orthographic projection. As a matter of fact all of them I know prefer the latter...

Why does he need 3D?

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