Seeking Recommendation on a Bench Grinder with Specific Features.

[Scott Memmer]

Hi, Everyone. I dearly love this forum, although I have not posted in a long time. You folks are so knowledgeable and always have such great suggestions.

Here is my situation. I make a small music accessory and need to build my own saw. Without going into all the details, I've been searching for a sawing solution for eight years. I've finally found the machine that will do the job, but even used ones are $4000-5000. I've made my own tooling before, so this won't be difficult. Thank you in advance for any advice and suggestions you may have.

I am knocking off a very expensive saw by a company named Buehler. Below is the link and specs and a photo. These saw used expensive diamond-encrusted blades that are water-cooled.

https://www.buehler.com/products/sectioning/precision-cutters/isomet-high-speed-pro/


https://i.imgur.com/eSLO3FMl.jpg










IsoMet High Speed Pro


Cut Operation
Automatic, Manual, or SmartCut control Linear Blade Feed


Units
English and Metric


Blade Movement Axis
Horizontal and Linear (X, Y, Z)


Display
6.5in LCD Display with LED Backlighting


Controls
Touch Screen; Precision Controllers


Lighting
2 LED Strip Adjustable brightness


Programming
Retains Last Settings Serial Sectioning


Laser
Optional Green Laser


Blade Position Settings
Horizontal: 0 – 2in [0 – 50mm]


Cut Length Range
.01 – 7.25in [1mm – 184mm]


Cut Length Increment
0.01in [.25mm]


Feed Rate Range
.04 – 1in/min [1.2 – 25.4mm/min]


Feed Rate Increment
0.01in increments [1mm increments]


Blade Speed
1000-5000rpm


Cut Capacity (Diameter)
2.8in [71mm]


Coolant Systems
Built-in Recirculating System, 1gal [4L]


Flow Rate Wash Down Hose
2L/min


Flow Rate on Blade
2.5L/min


Wafering Blade Diameters
3 – 8in [76 – 203mm]


Abrasive Blade Diameters
5 – 8in [127 – 200mm]


Cut Chamber Size
9in x 20in [228mm x 508mm]


Machine Dimensions
Width: 24in [610mm]
Depth: 30in [762mm]
Height (Hood Opened): 36in [915mm]
Height (Hood Closed): 19in [483mm]


Weight
157Lbs[71.2kg]


Electrical


Motor Power at 220VAC
2.68Hp [2kW]


Main Power
100 – 240VAC, 50-60Hz, 1 Phase


Noise Level
58dB


Safety Features
Interlock Hood Switch, Emergency Stop


Compliance
CE Directives



The bench unit I'm looking for is similar to the Harbor Freight model below, except I need a slower RPM and/or a variable RPM model. The features I need or will add are:

1) Water cooling. I can build a well for this.
2) Due to the water cooling, I need a unit with a long "throw" on the arms, to keep the blade as far away as possible from the machine. I will isolate and water-seal everything, but this feature will make the build easier.
3) 1750 RMP speed, or variable 1000-5000 range.
4) I always prefer to buy clean/used, so ideally the saw I buy is popular with many used ones in the market.
https://i.imgur.com/9pUwLnQm.jpg
Lastly, if someone is familiar with the strange world of these saws and has a solution I haven't thought of, I'm all ears.

IMPORTANT: I am a tiny company with zero profit. I cannot and will not belly-up for a used saw at $3-4K, no matter how clean.

Sorry to write a novel.

Thank You,
Scott

[Steve Mathews]

You may want to give a shout out to Cuttermasters. They apparently construct special application machines based on the Tradesman grinder.
https://cuttermasters.com/product-category/tradesman-dc/

[Scott Memmer]

You may want to give a shout out to Cuttermasters. They apparently construct special application machines based on the Tradesman grinder.
https://cuttermasters.com/product-category/tradesman-dc/

Steve, thanks so much. I will check them out right now.

sm

[Richard Coers]

I'd think an old horizontal mill with a vise on the bed would work well. They don't bring much money as most prefer a knee mill. $800 for this good example. https://www.facebook.com/marketplace/item/1535347640665316/?ref=search&referral_code=null&referral_story_type=post&tracking=browse_serp%3A4fb17cc6-144d-4d77-8dfc-e53b4b617116

[Bill Dufour]

Buy a used three phase grinder and use a vfd to run it slower.
Bill D

[Tom M King]

Look at Baldor buffers. They have longer shafts than grinders and come in 1725 rpm plus other choices. They even come up once in a while on Craigslist. You won’t ever wear one out.

[Tom M King]

Wet grinders like the Tormek are limited to 150 rpm so they don’t sling water.

[stephen thomas]

What material are you cutting?
IOW, would a tile saw serve you better?
A step up in precision and locational positioning could be a surface grinder. Old mechanical-auto machines are cheap.
Or as has been mentioned, a small horizontal mill, (probably?) with lever feeds. The big old machines are too slow rpm for your needs.
However, some of the small lever feeds can easily be adapted with an add-on spindle. I bought one at an auction last year for $5 and am building the spindle between work on the house.

Speaking of spindles, there are an awful lot of variable speed router spindles available for a few $hundred, including some that are water-cooled. Popular with cue makers.

As also has been mentioned, 3ph with VFD is the modern cheap means to get variable speed for many ops.

smt

[Bill Dufour]

Pretty much any three phase buffer/polisher will be very good industrial quality. As long as the shaft is not bent and the wheel arbor nut threads are good not much to worry about. Maybe bearings and you do not care about any missing guards or tool rests.
Bill D
Bill D

[Bill Dufour]

Replace the bearings with sealed ones not shielded. if needed.
Bill D

[Tom M King]

We don't know exactly what the end goal is, but I made a little sled for my tile saw out of Corian scraps for cutting multiple pieces exactly the same. With a glass cutting blade (also a diamond encrusted blade, but not sure of the relative rating of expensive), it cut pretty accurate pieces with smooth edges.

[Bert McMahan]

Could you get a small VFD spindle from a CNC machine and bolt it sideways? They make all sorts of blade holders for machine tools (look for "slitting saws" for a start).

[Scott Memmer]

I'd think an old horizontal mill with a vise on the bed would work well. They don't bring much money as most prefer a knee mill. $800 for this good example. https://www.facebook.com/marketplace/item/1535347640665316/?ref=search&referral_code=null&referral_story_type=post&tracking=browse_serp%3A4fb17cc6-144d-4d77-8dfc-e53b4b617116

Richard, thanks very much. Unfortunately, I have a very small shop and that would take up too much room. I guess I pretty much need a benchtop device with a small footprint, maybe 12" x 12".

Thanks Again,
Scott

[Scott Memmer]

As usual, you guys are full of the greatest ideas and options. I had no doubt you'd come through.

To give a little more background (I was rushed with my OP yesterday), we cut industrial, high-end plastics that are similar to Delrin or Ultem but are MUCH more expensive. These would include PEEK, TORLON, VESPEL, etc., some of the most expensive plastics on earth. The problem is that the cost of the sheet stock (vs rod) is about five to one, plus for many of these materials the thinnest sheet you can get is 1/4". We make guitar picks with this stuff, so most of our needs are in the thickness range of .040"-.080" (one to two millimeters). Below is a PEEK rod, for example. We typically buy these at 1.50 mm diameter, then slice off little pizza discs.

Maybe you guys have some other tooling ideas -- and if so, I'm all ears -- but here's our problem. Some of these materials are incredibly expensive -- again, among the most expensive plastics on the planet. For example, we use two materials where a 12" rod x 1.50" costs $700 or more. Therefore, the kerf loss (path of the blade) becomes a huge problem. You cut a .040" thick disc, you lose that much or more on the cut. The diamond blade solution offers blades as thin as .015-.020".

https://i.imgur.com/VA3q2iRm.jpg

I was lucky to find a stash of some of these materials at half of wholesale, so I've just been cutting them with a bandsaw, which works great, but there is a TON of material loss in that approach, along with a jagged surface area (I use high-TPI metal-cutting blades, but it still sucks).

sm

[Malcolm McLeod]

... blades as thin as .015-.020".
Materials listed are all thermoplastics. Have you considered hot wire cutters?

[Scott Memmer]

Pretty much any three phase buffer/polisher will be very good industrial quality. As long as the shaft is not bent and the wheel arbor nut threads are good not much to worry about. Maybe bearings and you do not care about any missing guards or tool rests.
Bill D
Bill D

Bill, thanks. I'm in L.A. and there a BUNCH of used Baldors around me for very reasonable prices. Question, if I may. It appears most Baldor 3-phase grinders run at 1750 RPM. If I hook one up to a VFD, is 1750 the fastest it will go without damaging the motor? I assume so, but I'm pretty much a newb to this stuff.

Thanks Again,
Scott

[Scott Memmer]

Materials listed are all thermoplastics. Have you considered hot wire cutters?

I've looked at this option vaguely. Did you have a particular machine in mind?

The problem is these plastics have widely varying melting points and other properties. Most of them do NOT like my laser cutter and leave a lot of char and clean-up after the cut.

Malcolm, could you please supply a link or two to the kind of machine you're thinking of?

Thanks,
Scott

[Scott Memmer]

What material are you cutting?
IOW, would a tile saw serve you better?
A step up in precision and locational positioning could be a surface grinder. Old mechanical-auto machines are cheap.
Or as has been mentioned, a small horizontal mill, (probably?) with lever feeds. The big old machines are too slow rpm for your needs.
However, some of the small lever feeds can easily be adapted with an add-on spindle. I bought one at an auction last year for $5 and am building the spindle between work on the house.

Speaking of spindles, there are an awful lot of variable speed router spindles available for a few $hundred, including some that are water-cooled. Popular with cue makers.

As also has been mentioned, 3ph with VFD is the modern cheap means to get variable speed for many ops.

smt

Thanks for your post, Stephen. Please see my post immediately about describing the materials I'm using.

Forgive my ignorance, but aren't electric tile cutters very high RPM? I need to be between about 500 to 5000 RPM at the very most.

Could you please post a link of the kind of machine you're thinking of?

Thanks Again,
Scott

[Aaron Inami]

For the round rods, one idea is to get a mini-lathe and then engineer some sort of ultra-thin cutter. It's likely just as much material loss as a bandsaw, but much more accurate.

The Little Machine Shop had the highest quality mini-lathes back when I was researching. This model is a true variable speed using a brushless DC motor (50-2500rpm):
https://littlemachineshop.com/products/product_view.php?ProductID=5100&category=1271799306

If you have square stock, you could engineer a saw cutter blade that mounted in the spindle jaws and then mount your stock on the radial arm. This would allow an ultra precise cut.

[Aaron Inami]

Bill, thanks. I'm in L.A. and there a BUNCH of used Baldors around me for very reasonable prices. Question, if I may. It appears most Baldor 3-phase grinders run at 1750 RPM. If I hook one up to a VFD, is 1750 the fastest it will go without damaging the motor? I assume so, but I'm pretty much a newb to this stuff.

Thanks Again,
Scott

You have to be careful when connecting a VFD to a normal motor such as the ones found in the Baldor 3-phase grinders. These are not considered "inverter motors" and you should really not run them less than about 40-50% (which limits you to about 700-875 RPM.

[Jim Becker]

There are very thin sawblades on the market that are typically used for cutting fret slots. Using or adapting one of these with a "micro table saw" (made for certain kinds of small project hobbies) and a precision sled for thickness stops might be a solution to create your blanks from the rod with minimal waste, but there is also that fine line around ideal blade speed that cuts without heating too much. That's always the big challenge with plastics and similar material.

[Tom M King]

Wire on this is .2mm.

https://www.amazon.com/Proxxon-37080-Wire-Cutter-THERMOCUT/dp/B0017NS8H6/ref=asc_df_B0017NS8H6/?

[Bill Dufour]

Vfd recommendation is not more then 20% overspeed or underspeed without checking if the motor is designed for more. Lower speeds are not a problem if you add another motor to blow cooling air onto the motor. As rpm drops torque drops the same percent. I run my drill press at 50% speed for several minutes at a time with no modifications. If you want low speed just use a more powerful motor. Example you need one hp at 750rpm. Use a two hp 1500 rpm motor at. 30 hz.
High speed is fine until the rotor or cooling fan fly apart from overeving. Regular ball bearing can go to 5,000 rpm or so just fine.
Bill D

[Tom M King]

And small tile saws:

https://www.vevor.com/power-tile-masonry-saws-c_12386/vevor-wet-tile-saw-7-inch-65mn-steel-blade-3500-rpm-induction-motor-tile-cutter-wet-saw-with-water-reservoir-0-45-degrees-miter-angle-for-cutting-tiles-and-stones-for-diy-enthusiasts-p_010524121464?

[Scott Memmer]

There are very thin sawblades on the market that are typically used for cutting fret slots. Using or adapting one of these with a "micro table saw" (made for certain kinds of small project hobbies) and a precision sled for thickness stops might be a solution to create your blanks from the rod with minimal waste, but there is also that fine line around ideal blade speed that cuts without heating too much. That's always the big challenge with plastics and similar material.

I hear ya. I'm looked at those solutions and I've used and do have those blades -- like, 5" w 320 TPI. Still iffy. This solution is better, I think, Jim, because the water offers superb cooling and avoids that overheating. The Buehler saws are superbly accurate too, with an armor that moves the workpiece in precise increments.

BTW, Jim, I just thought of something. I have a raw case of the same saw (pictured below) that came without a motor. I wonder if I could jury-rig this by inserting a higher RPM motor in there. I would probably want something in the one hp range, variable from 1000-5000 RMP.

What do you think?

Thanks,
Scott


https://i.imgur.com/VHjP1z1m.jpg

[Scott Memmer]

You have to be careful when connecting a VFD to a normal motor such as the ones found in the Baldor 3-phase grinders. These are not considered "inverter motors" and you should really not run them less than about 40-50% (which limits you to about 700-875 RPM.

Thanks, Aaron. That would probably be fine. What about the top RPM with a Baldor? How high could you go? Thanks again.

sm

[Wes Grass]

I did a nowhere near comprehensive search for carbide slitting saws. I'm thinking 3" dia the minimum for getting to the center of a 1.5" bar. The thinnest 'stock size' being 1/32" ...

Diamond being about the worst thing I can think of for plastic, basically 'sanding' the thing off. But if the waste is that expensive...

Possibly custom saws that are thinner ... but you also need a decent ... no, REAL ... spindle to put them on.

Hot wire sounds interesting... might also smell 'interesting' ... if not also toxic.

Too bad it's not available as sheet.

[Jim Becker]

I
BTW, Jim, I just thought of something. I have a raw case of the same saw (pictured below) that came without a motor. I wonder if I could jury-rig this by inserting a higher RPM motor in there. I would probably want something in the one hp range, variable from 1000-5000 RMP.
Sounds interesting, but I'm not a machinery guy for the most part.

[stephen thomas]

Thanks for your post, Stephen. Please see my post immediately about describing the materials I'm using.

Based on materials, i think you need coolant, but not abrasives.


Forgive my ignorance, but aren't electric tile cutters very high RPM?

See my previous note, i now disagree with abrasives. To answer your Q, no, not particularly high rpm, but they do have coolant. I think mine is 3250 rpm, but have not looked at the dataplate in years. (see post with pix someone else put up regarding tile saw) I can see very faintly possibly modding a tile saw to take a small saw. However, there are intrinsic limits to the control the sliding table offers. OTOH as a cheap "what-if?" i might well shop flea markets etc for a cheap one and try it out. Again, i would make an arbor to use a small saw and adapt the rest of the machine to suit.

One of the problems you need to understand, is that the saw (or the table) needs to travel so that the saw plate is perfectly flat to the plane of travel perpendicular to the cut. Anything less causes deflection for thin blades. Your idea of abrasives is a bandaide to (slightly) mask that problem, but it will still bite.



Could you please post a link of the kind of machine you're thinking of?

Well seeing more info on your project, slicer-dicers do come up on eBay sometimes for very low money because the chip fabs are done with them, and no one else has a use. So there's a thought.
Slicer-dicer's started out as factory modded surface grinders optimized to abrasive cut silcon wafers off the cast bar. You think your plastic is expensive per slice. :)

One thing about surface grinders is that they are optimized for feeds (steps) in increments of .001" and .0001". So after making a cut, you can reliably feed it in, say, .010" and that will be accurate if you know the actual cut thickness. Then you are just down to part-to-tool alignment, and deflection. :) Slicer-Dicers automate and optimize that process.

Sorry i don't have any easily accessible pix of better approaches to your specific project.
However, this is an over-view of the process. Spin the slug in a fixture, cut it off with the live spindle. Could be a lathe, or mill, too. I agree you need coolant, but still think a saw or parting tool is the better cutting implement.

519922519925

I'm actually modifying a (hardened) Cat50 shank collet chuck, and making a taper socket to fit one of my Hardinge lathes.....to run Ultem. (among other products)

519923519924

If i get a chance, i may be able to mock something up on a mill to show the saw process with Ultem 1000. But don't count on it before next week.

smt

[Bert McMahan]

Vespel is definitely not a thermoplastic, and you definitely do not want to cut it with heat. I'd suspect the same with PEEK but I haven't tried that one.

I'd vote slitting saw. They get crazy thin.

[Wes Grass]

Bandsaw ... I've 'heard' of people knocking the peaks off the set to improve the finish, and save a little material in the process. Make them somewhat resemble a carbide tip on a circular saw blade.

Keep the RPM down, and use coolant, and a hollow ground HSS slitting saw should work well too.

[Wes Grass]

One little, bad, detail re HSS saws. All of them I've seen have teeth that are milled before hardening. Then they're ground, bore and faces.

So they run out and usually only cut with a few of the teeth. So consider you might need to have them properly ground before use.

[stephen thomas]

re HSS saws. All of them I've seen have teeth that are milled before hardening. Then they're ground, bore and faces.

So they run out and usually only cut with a few of the teeth. So consider you might need to have them properly ground before use.

Amen!

Years ago, after making plenty of tooling, i came to the conclusion that somehow, over mulitple tries, i just did not manage to make good saw arbors.
Then one day i busted a saw, and the replacement had already been used up/dull.
So i groaned, pI$$ed & whined, and finally hauled out the fixture for my Cincinnati #2, set up, and sharpend the blade.
Whoa!
What a revelation!
It almost scared me - there was barely any noise. No throbbing, jerking "nYerk! - nYerk! - nYerk! - nYerk!" pulsing the infeed handle.
Just a quiet, steady "whirr" sound and chips pouring out with no fuss or bother.

Gear cutters are often about the same way.

[Rick Potter]

I assume this plastic will melt with friction, but if not, perhaps a 4 1/2'' grinder wheel with a 1/16 thickness?

[Bill Dufour]

Look also at a tool grinder. They are designed to run with a drip oil or water on the wheels.
Bill D

[Ray Selinger]

That saw is a lapidary unit. Diamonds are merely rocks, chuckle. I would look at what is available for lapidary. Then check local rock and gem clubs for used equipment. I have repaired some for my wife, the rockhound, and the rock and gem club see belongs to.

[Scott Memmer]

I assume this plastic will melt with friction, but if not, perhaps a 4 1/2'' grinder wheel with a 1/16 thickness?

Hi, Rick, thanks for your post. 1/16" is too much kerf/material loss. The material we're cutting in rod form costs $50/foot. That's not an exaggerated number.

[Scott Memmer]

That saw is a lapidary unit. Diamonds are merely rocks, chuckle. I would look at what is available for lapidary. Then check local rock and gem clubs for used equipment. I have repaired some for my wife, the rockhound, and the rock and gem club see belongs to.

Oh, my gosh, Ray, I'm sitting here slapping my forehead. I had looked at this option years ago, but thought these saws were too fast. This should do the trick -- and it's cheap! Thanks!

https://www.amazon.com/Hi-Tech-Diamond-Lapidary-Cutting-Trimming/dp/B01N9USCHR/ref=asc_df_B01N9USCHR/?tag=hyprod-20&linkCode=df0&hvadid=693672553565&hvpos=&hvnetw=g&hvrand=2999606005124559953&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9031113&hvtargid=pla-569553510949&mcid=78cda9010f3131a08b95591593f20884&gad_source=1&th=1

[Scott Memmer]

Vespel is definitely not a thermoplastic, and you definitely do not want to cut it with heat. I'd suspect the same with PEEK but I haven't tried that one.

I'd vote slitting saw. They get crazy thin.

Agreed, Bert. I've got a segmenting saw, but it only goes up to 300 RPM. I need something possibly ten times that fast.

Just be clear, Bert, are you talking about a CNC machine for the slitting? If so, I would have to job this out, which wouldm make our costs too high. I do have a CNC machine, but it is a small benchtop model with no water or coolant.

If you're referring to benchtop units, the industry standard is pretty much the Buehler Isomet line. However, the high-speed model I need is $4000-5000 for a clean used one, well beyond my means at this point.

If you have another specific saw or application in mind, I'd love to hear more.

Thank You,
Scott

Thank You,
sm

[Scott Memmer]

Bandsaw ... I've 'heard' of people knocking the peaks off the set to improve the finish, and save a little material in the process. Make them somewhat resemble a carbide tip on a circular saw blade.

Keep the RPM down, and use coolant, and a hollow ground HSS slitting saw should work well too.

Wes, hi, you and another poster mentioned the same thing, something about a smoother blade for a bandsaw. The little nine-inch band saw I have cuts this stuff beautifully, but the surface is very rough. Are there other blades I might try? I'm cuirrently using a metal-cutting blade with 18 TPI.

sm

[Ray Selinger]

Lapidary saw blades are measured in thousands of an inch. Gem stones are even pricier.

[Scott Memmer]

Lapidary saw blades are measured in thousands of an inch. Gem stones are even pricier.

Ray, yes, I'm familiar with the specs on lapidary blades. That's not the problem. As far as pricing, that is also not a problem. There are "diamond" blades to my spec (.025" or thinner) that will work just fine. (I suspect the cheaper diamond blades are synthetic, but they work just fine.)

The challenge is what kind of machine can I mount these blades on that will do the job. All the lapidary saws are water-cooled, as the excessive heat -- esp at 5000 RPM -- can burn and damage the diamond edge. I already own a Buehler Isomet segmenting/wafering saw, but at 300 max RPM it is far too slow. I cannot afford the faster Buehler saw, even used.

Again, I need the following features. I am now leaning toward a DIY solution, which I can do for probably under $500.00

[Bill Dufour]

Why not just change out some pulleys for a higher rpm. Is it plain bearing?
Bill D

[Bert McMahan]

I meant using a spindle from a CNC machine to make your own slitting machine. Something like this one:

https://www.amazon.com/Spindle-Inverter-Engraving-Milling-Cutting/dp/B073TRP92V/ref=sr_1_9?crid=2WGD6VOCWHXPS&dib=eyJ2IjoiMSJ9.L9-CnTIpsjhrdTl4sc0jzzGSXFhs8Gk2qmajpoZS7KRcsZRbS-KCZC5_px8SHDlR0C5xE-Ns8ycYlyLhvS2UMNPBjaHj7tGxkQ-Al3R2iAg8KRw2eQXr9fsPilv1W3RsLb5wTetS2ZWVL4-pcwr0mbB7Zs6MY8NlbqmTxiYJdNCDF7upbFcEqvEAFmQREGUWa-Zp9dG8mtA0S_YM3VoF_SGuJ3rCKtqoQUp6e-8fM9ewweNtfVEzfrybr3Rkk9uqAMdZKLMzPadYjocM4zOvVO8Y Aq3rorF4lq_mSopUnsY.D0KXxxPz2iu2JuJ5S9cFhoXkAgCUtA AcnC6m4UX1vHE&dib_tag=se&keywords=cnc+spindle&qid=1716238309&sprefix=cnc+spindl%2Caps%2C129&sr=8-9&ufe=app_do%3Aamzn1.fos.1740e8b9-be2d-46a4-a376-9d8efb903409

(No experience with them, just searched "cnc spindle")

You'd need to make your own system, but you could stick a slitting saw into one of those mounted horizontally and make a small slitting machine.

[Ray Selinger]

I repair the machines, I don't use them.I work with wood and metal, not rock. I checked one of the wife's 6" trim saws, it uses a 1725 motor 1to1. Just a quarter horse. This one uses mineral oil for coolant and lube. Her other one is for opals. The colour in opals is in contained water, so any heat would be a great problem, it would ruin the stone. They make your material seem like chicken feed. This 6" trim saw has even finer blade and uses water. The saw bases are filled with oil or water and the blades run in it. It is not quick. We paid around a hundred for the used saw, about that much for the blade, and we had a 1/4hp kicking around. I mounted them to a plywood base, added a guard and switch, and one of those lamps on an arm. A magnifying one would be deluxe. . The larger 10" trim saws also slab the stone. They have clamps for holding the stone for cutting. You could easily work something like that out in wood.

I joke I'm so cheap my wife has to make her own jewelry . She also does silversmithing.

[Tom Bender]

Not familiar with this material but here's an out of the box idea. What happens if you try to hand plane this stuff? If that works maybe you can shear it to the correct thickness (with a very sharp blade) and result in no waste and a pretty good surface.

No, a hand plane won't work, you'll have to make a shear with a good sized lever and a serious blade and a die to hold the stock.

[stephen thomas]

Per my earlier notes, tonight i played around with cutting a 1.5" dia piece of ultem 1000.
Also per my earlier notes, alignment is critical, deflection the enemy.
Using a 1/64" x 4" saw, using a set up that was on one of the vertical mills, i kept generating cones while gradually iterating the dividing head spindle a few (arc) minutes at a time to ameliorate the deflection.
This yielded improvement, but did not ever yield satisfactory (flat) results.

Next, i mounted a 1/32" x 4" saw, cut straight in, and then rotated. (As opposed to dialing in gradually while constantly rotating)
This looks promising, except it revealed a slight front-to-back lean between the work spindle and the tool spindle.
Basically, i have a good idea of what should be done, but don't really have the time to dedicate to doing it on a machine that nods. It may surprise some just how much time can get eaten up dialing all the axes in for a sensitive project to levels that are unnecessary for run of the mill but still close, work.

Saw plates/stabilizers to limit the blade rim projection to just over 3/4" (to cut to center of 1.5") would make a really big difference over the 1-1/4" projecting now. Or going down to a 3" saw and a slightly smaller arbor.

At the same time, since initially i envisioned this as live tooling on a lathe, (saw blade on a lathe) i began to wonder "what if" a parting blade were simply ground to 1/32" and set up on that machine. Way, way easier to dial in. But it will have to wait a few days again.

I do not think that abrasives at the speed you envision will be any less subject to deflection.
But of course would be interested to see what your experiments yield.

How do you currently cut the discs?
How much oversize?
How do you flatten them uniformly after parting them off?

smt

It also occurred to me that if it were my project, i might just get a small bandsaw (14", e.g.) and hollow grind a blade for it, down to say .020 cutting thickness, then set up the dedicated saw with coolant, perfect tracking, minimal strain, and a carriage with micrometer stop. However, my interest does not extend that far. :)

[Ray Selinger]

A band saw uses guides for their thin blades. I use graphite impregnated phenol board for my old Beaver band saw. Old saw mills used litne vitea pucks (some pretty bad spelling) on the saw blades on the big pony saws. This kept the blade from defection. The saw blades were slid back and forth for each slab, so the guides held them in line.

[Wes Grass]

Wes, hi, you and another poster mentioned the same thing, something about a smoother blade for a bandsaw. The little nine-inch band saw I have cuts this stuff beautifully, but the surface is very rough. Are there other blades I might try? I'm cuirrently using a metal-cutting blade with 18 TPI.

sm

I think I'd try flipping the blade 'inside-out' so the teeth are trailing, and pinch it between a couple stones until there's still just a hint of set.

Or, if you've got a vise with smooth hard jaws, you might be able to squeeze the set out. It's always going to spring back a bit, so you'll still have some clearance. Although I think there will always be a bit of a 'corner' left to generate a rough surface. But it might save a lot of stoning.