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Neil Jones
07-04-2009, 01:01 PM
http://www.novatechonline.com/products/mega/mega.htm#Blue

http://www.novatechonline.com/products/mega/MegaPoint-Blue-Demo.mpg

BadDog
07-04-2009, 04:43 PM
That looks similar to (clone?) the Optima grinders. Very high dollar, even used. Sure are sweet grinders, but hard to justify if you can't use it a LOT.

Do you just want to use it for drill bits? If so, look for a TRD/SRD. I've got one and it is one of the better tool investments I've made (though I did get it way below market value). They sell new for a bit over a thou for the base model, up to well over 2 grand for the deluxe loaded setup. But I got mine (base model) in near new condition at local auction for $40, and have seen others going for a bit over $100 lately. I then bought several replacement wheels (I guess I'll need them some day) along with a "small drill wheel" (what I was after) for $20 on ebay. Combine that with my "1/4 to #80" capable Christen and I'm pretty well set for anything smaller than (almost) 3/4". For larger, I borrow a friends large drill SRD (same guy that got me turned on to SRDs). He also has an Optima (2 actually), but like my Christen, they are too fiddly to fool with for a quick touch up for general use...

Neil Jones
07-04-2009, 05:20 PM
The Optima is the same thing. I've seen them in the thousand dollar price range. I am willing to pay that. I just want to use it for drill bits. The TRD/SRD does not have a built in optical measuring system like the Optima does. How do you quickly check to see that you have equal lips and even point splitting without an optical measuring system? This is the only system I'm aware of where you don't need trial and error to get the drill right the first time.

BadDog
07-04-2009, 06:43 PM
SRD/TRD has a fixed slide/wheel relationship and a fixed 180* "chuck". If you spark it out on both sides, you get equal lips of equal angle, and the "web thin" works likewise. I've looked at the result under magnification (should try it on my new comparator) and it seems perfect every time. My Christen does have optical check, but IMO it's all the more important on bits below 1/8" and more so as you go down. On the SRD I can have the bit touched up and back to work before you can get started with an Optima.

And even it it were a thou more accurate, does it really matter? As others have said before, drilling isn't a high precision operation to start with, no matter how perfectly the point is ground. My top criteria was "repeatable accuracy appropriate for the tool". A close second was "quick and easy so I don't put off touching up a drill". And somewhat more remote third was "reasonable cost". I've found not better answer for those criteria than the TRD/SRD M-80 (or if your lucky, one of the upgrades, but at least 90% of what you see is the M-80).

Neil Jones
07-04-2009, 06:57 PM
"SRD/TRD has a fixed slide/wheel relationship and a fixed 180* "chuck". If you spark it out on both sides, you get equal lips of equal angle, and the "web thin" works likewise."

Can it do these kinds of grinds?

http://www.novatechonline.com/products/mega/grinding_examples.htm

How is point splitting done?

"And even it it were a thou more accurate, does it really matter? As others have said before, drilling isn't a high precision operation to start with, no matter how perfectly the point is ground."

I guess that would depend on what someone is trying to accomplish. If you can skip a reaming operation and the need for a tool change, if you wish to drill more holes without resharpening, if you need to hold a tight tolerance and wish to get away from center drilling; then yes it does matter.

Mcgyver
07-04-2009, 09:17 PM
The Optima is the same thing. I've seen them in the thousand dollar price range. I am willing to pay that. I just want to use it for drill bits. The TRD/SRD does not have a built in optical measuring system like the Optima does. How do you quickly check to see that you have equal lips and even point splitting without an optical measuring system? This is the only system I'm aware of where you don't need trial and error to get the drill right the first time.

the first one? well here's the second :D

http://bbs.homeshopmachinist.net/showthread.php?t=15226

Mcgyver
07-04-2009, 09:23 PM
"I guess that would depend on what someone is trying to accomplish. If you can skip a reaming operation and the need for a tool change, if you wish to drill more holes without resharpening, if you need to hold a tight tolerance and wish to get away from center drilling; then yes it does matter.

you're new at this aren't you? don't get too wrapped up in having to have everything perfect, at least so far as drilling goes. BD is right, drills serve a purpose then there's reamers and single point boring when more accuracy and a better finish is required. the drills you sharpen on that or any other rig are going to cut better than .002" and .002" doesn't replace reaming. My drills cut to a couple of thou but that's still not reaming and nor is the finish.

Neil Jones
07-04-2009, 10:37 PM
"don't get too wrapped up in having to have everything perfect"

My idea of perfect is cutting cycle times and making more money. What's your idea of perfect?

BadDog
07-04-2009, 11:29 PM
Can it do these kinds of grinds?

http://www.novatechonline.com/products/mega/grinding_examples.htm

How is point splitting done?

The base model does standard helical and 4-facet grinds (aka "web thin", or some call split point, but not really) easily/quickly, plus it can do 6 facet with an extra step. That covers most of those pictured. There is also a point split attachment if you want "real" split points. So that only leaves the 3 flute and flat bottom (plus boring bars, but that's OT). And those (and a lot more!) can be done with the up graded models/attachments, all for less than an optima.



I guess that would depend on what someone is trying to accomplish. If you can skip a reaming operation and the need for a tool change, if you wish to drill more holes without resharpening, if you need to hold a tight tolerance and wish to get away from center drilling; then yes it does matter.
Getting away from spot drilling (not center drilling) is a function of bit aspect ratio (ex. screw machine vs jobber) and chisel point/web geometry. Longevity is more a function of lube/coolant and speed/feed as well as bit material. "Perfect" sharpening will have little effect on either once beyond the point of diminishing returns. Optima, SRD/TRD, Lisle, Christen, Darex, most anything beyond a Drill Doctor will get you well beyond that point, so not really relevant in my mind.

If you expect reaming finish/precision with any drill, I think you're either barking up the wrong tree, or have lower expectations/requirements than I envision for something expected to take the place of reaming/boring as a separate operation. If a "near perfect" drill gets you close enough, and an SRD drill won't, AND it's a matter of time/money (i.e. production business) then dropping a grand or more for drill sharpening would surely be worth it. But for HSM or short run (which is the focus of this board, hence my assumptions) I sure don't see it. I've got access to Optimas that I can "borrow" time on, and I have no inclination to do so. The only exception is that I have a solid carbide counter sink with a tiny chip in the edge. One of those Optimas has a diamond wheel, so now that I think of it, I may be borrowing a bit of time after all... :D

Either way, good luck with your search. For me, the SRD was perfect, I just wish I could find one of the "large drill" versions and one of the swiss-army knife versions to fill out capabilities beyond just drills. But my Toolmaker TC Grinder will cover that stuff once I've finished it.

oldtiffie
07-04-2009, 11:35 PM
Part of "cutting costs" - or cost-control in general - is amortising what ever you buy for the purpose over a reasonable time with reasonable risk with a reasonable internal rate of return on invested capital.

In short, do only what is needed at least cost and risk and show a profit.

All or many of these tools are really mechanised ways of paying for what should be basic skills.

I'd be more interested in making jigs and fixtures to do the job quickly, with minimal skills on a pedestal drill.

If I were going to "mechanise" it, I would use this grinding accessory for my grinders. I have two of these accessories which are brilliant in doing what they are designed to do - but I rarely if ever use them. They would be ideal for a small production shop as I'd have a box full of each drill I needed (cheaper in bulk) and just change them as and if required and re-sharpen at the end of the day or when I had time.

These are expensive new but should be about at reasonable cost in good condition. All that is required is to set the angles and the number of teeth/flutes required, turn the handle and away ya go. Couldn't be easier. It can "index" as well as doing the ends of end-mills and changing the "rake" of drills and web-thinning etc. A good one shouldn't cost much. The big "secret" is that long-nosed 6-jaw very accurate chuck. I have used it for limited cylindrical grinding (IC engine valve faces included) and form grinding on a shaft/spindle/tool etc.

In short, I'd suggest specifying what you need to do a job and then set about finding a tool to do it rather than finding the tool and "making it fit" or "seeing what I can do with it".

Short of that - Mcgyver's accessory is hard to beat if you want to make a tool. Put a "vise" on that tool and you can grind just about any lathe tool very accurately - and without a "Baldor" or similar grinder.

That's as nice a bit of work as regards detail, finish and "fit for purpose" as I've seen for a while Mcgyver.

http://i200.photobucket.com/albums/aa294/oldtiffie/Drill_grinder1.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Drill_grinder2.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Drill_grinder3.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Drill_grinder4.jpg