rockrockrock
noticing nice landscape pebbles
Member since August 2016
Posts: 91 
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Post by rockrockrock on May 19, 2024 2:07:59 GMT -5
Hello, Everyone. I haven't been on here in a long time, but you folks are always full of great advice and information.
I have need in my manufacturing business for a lapidary trim saw. I actually cut high-end plastics such as Ultem, PEEK, Torlon, Vespel and other ridiculously expensive polymers. I buy these products in rods that are 1.50" in diameter, then part them off in little discs that range from .040"-080" thick. (Please don't recommend buying this material in sheet form. It is insanely expensive in sheet form AND most of them don't come any thinner than 1/4"/.)
I'm going to list all the features I need below; however, the single most important feature I need is VARIABLE SPEED. Since I will have to experimenting with different blades and speeds and adjust accordingly, a variable speed saw simply won't fit my needs.
I see the Hi-Tech Diamond saw out there everywhere, so I may just go that route. However, if there is something similar out there with a metal casing, that would fit my needs better. Still, the plastic case on the H-Tech model is not a deal-breaker.
Here are the features I need:
* Variable Speed (most important)
* 6-inch blade
* metal casing (preferred)
* used or new
* under $1000.00
Thanks in advance for your suggestions.
RRR
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Post by Rockoonz on May 19, 2024 2:30:21 GMT -5
If what you're cutting requires torque, which in my experience of over 40 years in polymers was always important, a high tech, or any of the plastic or even metal direct drive saws will not be sufficient.
Look for a saw without a motor, then add your variable speed motor, I am using a Consew 1/2hp servo on my faceting machine, found on Amazon. I believe it goes about 500 minimum to 3500 or so RPM, variable top speed set on the controller plus a lever to adjust speed or stop it with a floor or knee pedal like the sewing machines it was made for. Since it is made to use a belt, I use pulleys to reduce the top speed and increase the torque.
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rockrockrock
noticing nice landscape pebbles
Member since August 2016
Posts: 91
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Post by rockrockrock on May 19, 2024 14:59:47 GMT -5
If what you're cutting requires torque, which in my experience of over 40 years in polymers was always important, a high tech, or any of the plastic or even metal direct drive saws will not be sufficient. Look for a saw without a motor, then add your variable speed motor, I am using a Consew 1/2hp servo on my faceting machine, found on Amazon. I believe it goes about 500 minimum to 3500 or so RPM, variable top speed set on the controller plus a lever to adjust speed or stop it with a floor or knee pedal like the sewing machines it was made for. Since it is made to use a belt, I use pulleys to reduce the top speed and increase the torque. Thanks so much for taking time to respond. I suspect you're right. The Buehler Isomet saw I'd love to own is over $30,000 new, and even clean used ones are in the $4-5K range. That's way far away from where I an now, or will be in the near future, so yes, I'll probably be looking at DIY project. I've created my own tooling in my business, and I've saved a bundle in the process. I'll probably do that in this instance as well. However, one thing. I'm an English teacher and the belt and pulley thing will drive me insane. I know, I know -- but my brain doesn't work that well, and it will take me too long to learn how to do that, so I'll just have a find the best motor I can closest to my needs. Trust me, I'm an idiot when it comes to math and science. Speaking of math and science, Rockooz, I ran a torque formula on the Buehler saw I mentioned above. The machine has a 2.68 HP motor. Here are the numbers (hope I did it right): at 1000 RPM = 2.85 lb/ft at 5000 RPM = 14.076 lb/ft A few quick questions, if I may: 1) How thick were the polymer pieces you have cut? The thickness I will be cutting is 1.50". 2) How kinds of plastics have you cut? 3) Ideally, how much minimum torque do you think I'll need? I'm not looking for concrete numbers, just ballpark. Thanks again. Your post has been most helpful. RRR |
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Post by Rockoonz on May 19, 2024 17:35:56 GMT -5
In the past I have cut solid SBR rubber over 4x4" to be spliced, had to freeze it with dry ice to get straight cuts with the large radial arm saw we used.
Set up lines to cut a lot of elastomers with a custom built wet saw, mostly rubber and silicon rubber, the plastics I worked with were epdm and a variety of TPE materials.
If what you are cutting is all in the D-shore durometer range deflection won't be the issue it is with A-shore materials, but kerf loss and surface finish may be a consideration depending on the requirements of your application. a 6" blade is pushing the capacity of a 6" blade if the requirement is super high precision.
Seems like a precision chop saw is what you want, better to move the blade than the material.
As far as belts, pulley calculations are as simple as this: Motor speed multiplied by motor pulley diameter, then the product of that divided by the arbor pulley diameter will give you your arbor RPM within a percent or so.
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rocknrob
has rocks in the head
If Costco only sold slabs in bulk...
Member since May 2024
Posts: 611
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Post by rocknrob on May 21, 2024 12:00:54 GMT -5
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rockrockrock
noticing nice landscape pebbles
Member since August 2016
Posts: 91
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Post by rockrockrock on May 21, 2024 14:44:19 GMT -5
Rob, hi, thanks, this looks like an absolutely terrific saw except, as I mentioned in my OP, it absolutely MUST be variable speed, not constant. Nothing else will suit my needs. Here's the reason why. I'm going into an area about which I knew very little. For my application, I will have to do a lot of experimentation to find the correct speed for my needs AND the type of blade(s) to use. Some of these blades are extremely expensive (the Buehler factory blade is $800), and I have neither the time nor the budget to experiment. The Buehler saw I'm attempting to replicate has an RPM range of 1000-5000. I know this saw works because they've done some beautiful test cuts for me. The problem? To job it out to them is $10.00 per cut, and that is far too expensive, so we have to figure out how to do it ourselves. If you know a saw similar to the one you recommended that has variable speed, I'm all ears. Thanks Again, RRR |
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rocknrob
has rocks in the head
If Costco only sold slabs in bulk...
Member since May 2024
Posts: 611
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Post by rocknrob on May 21, 2024 16:03:32 GMT -5
Rob, hi, thanks, this looks like an absolutely terrific saw except, as I mentioned in my OP, it absolutely MUST be variable speed, not constant. Nothing else will suit my needs. Here's the reason why. I'm going into an area about which I knew very little. For my application, I will have to do a lot of experimentation to find the correct speed for my needs AND the type of blade(s) to use. Some of these blades are extremely expensive (the Buehler factory blade is $800), and I have neither the time nor the budget to experiment. The Buehler saw I'm attempting to replicate has an RPM range of 1000-5000. I know this saw works because they've done some beautiful test cuts for me. The problem? To job it out to them is $10.00 per cut, and that is far too expensive, so we have to figure out how to do it ourselves. If you know a saw similar to the one you recommended that has variable speed, I'm all ears. Thanks Again, RRR ----------------- I'll keep an eye out for you but the only things I've seen so far have been these with some strong motors but not variable speed. If you have an engineer friend handy, you might be able to hack an older trim saw with some parts to make it variable speed though via mechanical and electrical means. That's what I meant as a "governor". I'm not sure if that was the correct term but what I was trying to say was an electrical switch that controls the amount of current the motor gets. That way you get the variable speed you're looking for (more current = more speed) But to get above the current maximum speed you would need to increase the saw blade speed. - Rob |
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QuailRiver
fully equipped rock polisher
Member since May 2008
Posts: 1,640
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Post by QuailRiver on May 21, 2024 16:23:13 GMT -5
I have heard of people adding an auxiliary rheostat type speed control to the power feed motors on Raytech and Lortone saws that use Dayton gear motors to power the powerfeed system. Raytech has a 10" slab saw with the separate powerfeed motor and in the past used to make a 6" version which used the same Dayton gear motor for the powerfeed. The 6" ones show up from time to time on eBay and Facebook. This is what they look like:    And I believe that this is the Dayton gear motor that the Raytech 10" and 6" saws use as well as the Lortone 10" saws and maybe the Lorotne 12" saw also. www.amazon.com/Dayton-3M098-Gearmotor-AC-RPM/dp/B018A1IG1KIf you need faster feed speeds I see no reason why a fster rpm motor could not be substituted and a speed control unit added. |
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Post by Rockoonz on May 22, 2024 7:47:40 GMT -5
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rockrockrock
noticing nice landscape pebbles
Member since August 2016
Posts: 91
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Post by rockrockrock on May 22, 2024 12:44:08 GMT -5
Hi, thanks again for this. I wasn't aware of the speed control issues on cheaper motors. Appreciate the info. Honestly, I must tell you that the pulley thing won't work for me. I'm an English teacher and my brain does not work that way. I know, I know -- it ain't difficult. But I teach full-time and every moment is preciious. Thanks again, Scott |
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rockrockrock
noticing nice landscape pebbles
Member since August 2016
Posts: 91
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Post by rockrockrock on May 22, 2024 12:49:47 GMT -5
I have heard of people adding an auxiliary rheostat type speed control to the power feed motors on Raytech and Lortone saws that use Dayton gear motors to power the powerfeed system. Raytech has a 10" slab saw with the separate powerfeed motor and in the past used to make a 6" version which used the same Dayton gear motor for the powerfeed. The 6" ones show up from time to time on eBay and Facebook. This is what they look like: And I believe that this is the Dayton gear motor that the Raytech 10" and 6" saws use as well as the Lortone 10" saws and maybe the Lorotne 12" saw also. www.amazon.com/Dayton-3M098-Gearmotor-AC-RPM/dp/B018A1IG1KIf you need faster feed speeds I see no reason why a fster rpm motor could not be substituted and a speed control unit added. Quail, this is terrific info. Thanks for taking the time to post the pics and links. I'm actually beginning to think that my first step should just be to try a single-speed motor that runs at 3450. That would be a cheap and inexpensive way to find out where the speed needs to be. That's ten times faster than the 300 rpm I'm running right now, so that would likely give me the data I need. Thanks Again, Quail. |
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iamchris
has rocks in the head
Member since June 2023
Posts: 722
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Post by iamchris on May 24, 2024 22:02:14 GMT -5
I'm zero help as to what you're looking for, sorry.
But I am insanely curious as to what this use case is for. This sounds like a whole new world I'm completely unfamiliar with. I'd love to learn more if you're willing to share.
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