Toolgrinding: Four facet grind
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- čas přidán 24. 08. 2019
- Grinding drills with the four facet geometry on a Dbit grinder and thinning the web using the t&c grinder.
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gtwr.de/
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#practitioner_of_the_mechanical_arts - Věda a technologie
i really like how you get to the point.
(see what I did there?)
Hmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm.
Its almost like it was his primary focus!
Sometime getting to the point means splitting it ☝️
I think that was a bit of a fluke
Ha ha. Thanks Dad.
My ancient carbide lore warns me of carbide's brittle nature and raises concern for the fragility of highly positive cutting edge angles. The lip of a twist drill is a prime example where the positive angle equals the helix angle of the twist - possibly 15 degrees in the case of the carbide drills you exhibited. My first impulse would be to grab a diamond sljp stone and "back-off" the cutting edge of the lip to 5 - 7 degrees positive to a bright line - 0.003" (0.08 mm) or so. The object is a geometrically stronger cutting edge less likely to chip in the cut. More holes per grind.
My carbide experience began to peter out when I became a bureaucrat in 1985. I understand carbide technology has improved over the years to rival the brittler grades of HSS. Regardless, a neutral or negative rake would normally be recommended for hard drilling. Hand stoning to consistant edge geometry is chancy at best. Could your D-bit grinder reach the back-off angles I referred to?
In any case, I think a D-bit grinder would benefit if equipped with additional work head swivel whose plane of rotation is parallel to that of the spindle. You could reach more wierd angles and planes. It would be a tricky project to implement withour making the workhead cumbersome.
"I wanted to do something new - a series on toolgrinding..."
INSTANT LIKE
The d-bit grinder (PP-U3) and the correct use of drill extension will automatically obtain your sharpened drill with 4 facets. The first is flat and the second gradient conical profile, this with one operation.
You can see detials in my videos about this.
For the chisel point reduction, it is also feasible on the D-bit grinder. If the drill is well sharpened, 2 identical large chips must be obtained and 2 identical small chips caused by bit tip reduction. With this device the latter is difficult to obtain two small chips but it is sufficient that there is one. I only use the chisel tip reduction for cobalt drills and carbide drills.
In attachment of these videos you can retrieve a document about the machine settings with the necessary explanation.
Because you carry out different machining on a separate basis, it means a lot of time and several grinding machines are needed.
The different steps are already well explained, with very good detailed recordings. Thank you Stefan
This was a good time for this video. I recently bought a Deckal clone. Now when I get the current job finished I can learn to use it.
Great we get to watch in the Am this video. We come to learn from Stefan, so lets watch and see and listen to what he is sharing for us. Through hole coolant cutters and drills they are amazing wish they were prevalent in our younger machining days.
Thank you for, as promised more learning here. 35:50 in is for us small micro mini things work for us love it you have a good selection in our area of cutting.
Lance & Patrick.
Hi Stefan i bought a Holzmann dbit grinder which was build in the 90s but was rarely used in a premium condition and it looks exactly like yours ,colours etc all identical...I started metal working with 40+ years about 10 years ago and you and old tony were an important part I thought come on let's try ...now with 50+ I have two rooms full of machines obe with lathes and mills ( CNC and o.g. style😂) etc etc the other with all grinding stuff because i want the grinding dust far away my other machines...my tools i bought costed some ten thousand of euros but i still love it thank you for your help and advice 😉👍
Stefan, thank you for another informative video. I've been watching all of your old videos and am picking up many very useful tips on precision machining!
Another excellent video. You really excel at these in-depth technical how-to explanatory/instructional videos. Thanks for taking the time and effort to make them and share your knowledge.
Great idea for a series Stefan, and a perfect first episode for me (since I have a D-bit grinder and plenty of old drills to play with👍👍)
Thankyou for another lesson, so well explained with pictures showing the important details and the reason behind them. Great idea for a series on tool sharpening as dull tools are painful!
Thank you! I have been wanting to do 4 facet grinding for a long time now, I have 20 kg of dull drills from work. Thanks for showing me how!
One more perfectly explained topic. I've been fiddling around with my d bit grinder for a year now and I've never acomplished to grind a 4 facet drill bit. Now all my drill bits are going to receive the "Stefan's touch". I am really looking forward to find the next video of your " tool grinding series".
I did learn something... I have to grind an endmill edge for a special purpose use and this was helpful.
I think you the most informative channel on machining and tool making on CZcams ! Thank you very, very much.
Thx for your vids Steph. Enjoy your detail to high percision. Keep them coming my favorite European machist. 😁👌🇨🇦
Thank you Stefan that was very enjoyable not to mention informative. Very nicely done.
Nice job, tip thinning is well worth the time and extends the life of the drill, plus more accurate hole size and location, plus more holes per drill. Nice job on the demo and explanation. Enjoyed.
Such and awesome and informative channel, deserves 10x the current subscription number.
Immer wieder eine Augenweide deine Videos anzusehen, Danke fürs Zeigen.
Timely video Stefan, I just bought a Wadkin T & C Grinder and will be learning how to use it as soon as it is setup in my workshop, so this helps me before I even start, Thanks from John, EC Australia. Cheers.
Thanks for the excellent video Stefan, I really appreciate the time and effort you take to pass your knowledge on. Regards Sarah
Thanks once again you prove you talent as a teacher.
More useful info from Stefan,thanks.
Nice video, thanks for the tool grinding tutorial. Will be on the lookout for a tool grinder.
I've been looking at second hand Deckel SOs just in the last week - a very well timed video for me, thanks Stefan!
nice friday afternoon chores grinding all worn drill bits. Stefan gets it all right.
This is great! I can't wait to see some more. THX : )
Many thanks hanks for the video Stefan. It was just what I needed. I doing have a D bit grinder only a universal tool and cutter grinder but it should all transfer. I have a sack of drills that need grinding.
I always thin the webs using a cut off wheel and my angle grinder. Not super precise but it works. :-)
I can do a drill regrind in the field, kneeling on a anglegrinder too ;)
Field Drill Gauge: Two hex nuts held together.
@@StefanGotteswinter 118 degrees, 120 degrees. In the average field, both are good enough! Komplimente an deine technische Sprachkentnisse.. All good stuff.
If you are concerned about the camera being in line of fire of the grinder, you could setup a mirror in line with the grinder and point the camera at the mirror. It might also make it easier to get shots where the camera would not fit.
Long live the D-Bit grinder. A lot more useful than people give it credit for. Thank you for showing how simple it really is. I will be making a right-angle magnifier with an alignment mark to do very small drills (old eyes need some help.) I use an ER16 straight shank chuck, which I cut the back down to give more length clearance (the part right behind the nut doesn't need to be as long as it is).
thank you for your time to produce, discuss, demonstrate this video....enjoyed the lessons
Great video, very informative. Thank you very much. I bought a Decker clone a few months ago, still haven't used it. Need to make a jig for alignment to grind the flutes of end mills. Thanks again!
Thanks Stefan, really looking forward to more episode in this series.
Thanks! Next one is already filmed.
Thin the web.....always. Great video love your work!
Excellent series topic! All the machines and techniques are for not without sharp tools. I bought a D-Bit grinder following your example and videos on the topic; what a world of difference! It is the only way i seem to able to produce perfectly ground lathe tools. All the tool grinding videos you care to produce would be greatly appreciated. I still struggle with grinding radi on the D-Bit grinder - Perhaps you could include that in your series.
Thanks Stefan!
Yes!! Tool grinding series!!
Excellent video! Thank you !
Thank you for a video! Very interesting knowledge 😊
I just love the german pronunciation of "Z" as "Sea" . That is adorable. And authentic.
Always something new for me to envy... your "screaming" German dust extraction compared to my cheap Chinese-American shop vac which is loud enough to break up riots. I love quiet tools!
Hi Stefan, I know it may sound silly, but you can try to fill the drill bits holes with fluid, cutting oil for steel and wd 40 for alluminium. Just put some wax on the holes on the cutting edge, fill the drill, and go, When you start drilling, the wax goes away and the fluid works. I have tried with good results, but you have to make some tests according to materials and cutting speed. Yes, is not how that drills are supposed to work, but for amateur job is good.
I know I need at least a Deckel (clone), and thanks to you knowing and sharing this I know where to start with it.
A+ is your grade for this tutorial Stefan. I know a little about this topic but it is amazing how much you learn seeing it from another perspective. Well done and thank you.
excellent, and good idea
Excellent video Stefan!
You are giving me good excuses to convince myself to buy a surface grinder
I'm 90% convinced
A surfacegrinder belongs in every household!
As always informative, thank you Stefan.
I have dreamed of having a D bit grinder..
Sigh, one day.
And I have bought a clone!
Then, of course, I revisited the masters lesson.
Ohhh, how good are Stephan's explanations!
Thank you again Stephan.
Thanks for the video. Waiting for the end mill sharpening video.
A metric mile. I like it. I added it to my lexicon.
Is an actual unit in Sweden, means 10km
Talking about collets, My U2 grinder shipped with just three Deckel style collets (4,6,8mm) which is severely limiting. I was expecting to buy additional collets but not expecting the price to be so high - £20 each in the UK! So I bought another two collets (10,12mm) for the end mills I most commonly use. I have an ER11 collet chuck on an 8mm shank, ideal for small drills and milling tools, but I'm still unable to grind anything bigger unless it fits a collet. My solution for drills - 3d printed sleeves that fit in the 12mm collet. Simple design - 12mm od with a 15mm flange, id sized for each drill, 1mm slot cut through on one side. Seems to work very well, and they could easily be made from a more durable material.
Thanks for the video.
Superb video Stefan ! Setting up the camera to get those close in shots on the grinder without destroying the camera must have been a very fiddly job .
Just ran across your channel. I do industrial sharpening and grinding. Real good job explaining the geometry! It’s not normal to find a machinist with grinding abilities these days. Good job!!! The drill you are doing should be 135 degrees split point.
Thank you!!!
Fascinating... :)
Excellent explanation, thank you Stefan! However, I fail to see why the web-thinning can't be done on the D-bit Grinder? What am I missing? Surely the work head can be rotated to get the same angle? I don't have a D-bit grinder yet, so perhaps my limited understanding of its limitations contribute to my confusion
really excellent camerawork on this video
I was taught to kick the the spin fixture out of parallel with the table so that the wheel is sort of "chasing the flute" when splitting the point. It's important to leave at least some chisel there.
Interesting, I have to try that , thanks- Just by looking at tool geometries its sometimes hard to figure out how they are ground.
Thanks Stefan.
We just bought a gerardi modular vise. We will send it back today. The quality was bad. It had a bunch of sharp edges ,even on the jaws. But the worst problem was that the moving jaw wasn't mowing freely. It was so gippy that we had to open it with a plastic hammer, and it wasn't chips stuch in the ways. I am looking forward to your review about this vise.
Wunderbar !!
Hello Stephan!
Do you have experience with secondary cutting edges? (it's like a chamfer on the end of the drill bit).
In an article I read some time ago they stated that those secondary cutting edges increase the drill life by up to 700%, decrease the tendency to drill crooked holes and leave a much better surface finish.
Nice video Stefan...Thanks for sharing. I wonder if a small height gauge on the bed of your grinder would help lining up the cutting edges...Probably more accurate than trying to eyeball it in with a stack of parallels.
The Tormek system feels like a really god alternative now that I have seen this. Both regarding price and easy to use 👍😀
Thanks for this bit of useful information. I really like the Why+How approach.
I have a Schaublin SV-51 milling machine that is older than me and I am missing a good vice for that one.
After looking around I found out that most of the vices are just too big for this machine. They would look hilarious sticking half the way out of the table. The Gerardi modular vice was the one that I found suitable. Not because of the obvious accuracy but the size and the versatility. It is not cheap but maybe I can convince my wife to accept the price.
I am looking forward for Your video on this vice.
Which size is the one You have ? ART1 A or B ?
looks like a nice 25.4mm cross-slide there!
I'm a little surprised that your D-Bit grinder doesnt have vernier graduations on the scales. The D-Bit looks like it works better than the Darex we have at work. On those the second operation for the back relief is prone to getting out of adjustment
I think you can read my mind. I was struggling to understand my DRO a while back, and you made a video on storing tools with the SDM function. Last week, I got new drill bits and they have this grind, and I have been thinking "Now how do I sharpen these?" :)
Slightly more sophisticated than AvE with an angle grinder in a vice
Angle grinder? More like Manitoba Monarch.
Nice work Stefan!
ATB, Robin
Thanks Robin!
Great video
Cool man 👍 cool! Thanks
What grit wheel do you use?
And NYCNC did a video on 135 4 facet drills, and found they still wander quite a bit... spot drilling was much more precise.
Machining a drill bit Hmm? Do you believe a Ohioan or a German?
old New England (upper NE USA) adage:
use it up.
wear it out.
make it do.
or do without.
[ yeah, we cheap! ]
New favourite saying: a metric mile
"A very harmonic experience"... sounds like a whale song relaxation album.
Hallo Stefan
Danke für dein informatives Video. Das war wieder sehr lehrreich für mich, da ich seit kurzem auch einer Stichelschleifmaschine habe.
Du hast ja deine Stichelschleifmaschine überarbeitet. In deinem Video, bei 4.45 Minuten ist an der Maschine eine runde Aluplatte mit 4 Inbusschrauben zu sehen. Wozu hast du die dort angebaut? Hast du das irgendwo im Netz dokumentiert?
Mach bitte weiter so tolle Videos.
LG aus Hamburg
6 Facet Drill Grind? As described in the article by Joseph Mazoff in Modern Machine Shop Magazine... in the year 1990's. How would you grind a 6 Facet Drill? Thank you for the fantastic video!
Love your videos, and why wouldn't I?
Have you read or heard of DAG Brown's work on grinding four and six facet drills? He designed a simple jig for manual sharpening of small 4 facet drills which was adapted by GadgetBuilder and further developed by yours truly. He is also known for his demonstrations of 4f grinding on a Quorn T&C grinder at exhibitions here in the UK. He advocates angles more in the order of 10 and 25 for ordinary HSS drills , which give a more pronounced point where your chisel exists , before you add the web thinning.
Drill sharpening is a very complex subject and has, it seems, fascinated the likes of Prof. Jorg Hugel for decades, his book might be of interest if you into scholarly tomes.
Can anyone tell me in which video Stephane describes the uses of his magnetic lathe chuck? I found the one where he machines a nut on it but I thought there was another one where he describes its use in detail. I just stumbled on one for my lathe and I would like to rewatch it. Or have I invented this memory?? Pretty soon we're going to need an index as he has produced so much great content.
Very nice
I'm not familiar with the type of collet used on these universal gringers. I'm curious if the head on this tool can be re-cut and ground to fit an R8 style collet as they look very similar 🤔
How the heck do they make those helical coolant holes in carbide???? Great video.
They get extruded into the green, unsintered carbide blank.
Ok didn't realize that those are sintered. Thank you.
@@sblack48 ...Carbide production is a sintered process
Is explained here: czcams.com/video/bo_IUu6U4ao/video.html
OT but I need to know the name of the classical music at the start.. It's been stuck in my head for a month and I tried listening through most all the classical music I know and some I didn't, tried audio recognition humming it etc., it's been driving me nuts.
Also have been using your technique on my drillbits for a few weeks now and it's saved me a lot of hassle when I've been low on certain sizes btw!
Very interesting, thanks. A metric mile??
Darex was mentioned below once. I've followed them for years and found their gear fascinating. I bought the V1 "drill doctor" and it includes fairly easy capability to split the point (thin the web) although the primary grind is more or less the traditional 118 or 135 degree grind. Using it and I gather their more professional machines is the same. A lot like sharpening a pencil although mine requires a bit more skill than that but for small drills about the same amount of time.
I wonder if you have tried sharpening your really small stuff? < 2mm? The drill doctor works fairly well on 3/32" to 3/8" drills. Bigger ones I can free hand grind well enough and smaller ones cannot be held in the chuck. Guy Lautard mentioned a gizmo for very small drills in his MBR series and I wondered if you had tried that method.
Definitely worth sharpening even cheap tools when it only tanks a minute and the cutting performance is so great afterwords. In tough materials I've resharpened the same drill several times for a single drill session (masonry usually).
I also really appreciate tool grinding videos. The D-Bit grinder is new to me and really intriguing.
For small drills 2mm and under I just use a good lighted magnifier and use a slip stone to sharpen them. It usually only takes a couple of strokes to get the tip back to sharp.
does the direction of the grinder matter? ex towards the front of the cutting edge or the opposite?
Hope that grinder does more than drills
👍👍👍👍
I really like video it I inspire me to forward on the trade 😊😊😊😊😁😊😁👌😁😊😁😁
1:00 how do they cut those coolant holes inside the spiral or are they actually just straight holes?
Whats up with that parallel in the mill? Looks like a rat chewed on the end. There has to be a story there.
All the best,
Tom
probably just a rat chewed on it, always go with the obvious.
@@sydneyshinshi or a kitten
@@jeromedumalin9954 One of This Old Tony's kittens?
If I had to guess, somebody tried to grind a radius form tool out of it. I need to clean that end up. Thats what you get when buying a large lot of tooling from your employer ;)
In Germany the rats have carbide teeth! 🐁
Can you do a video on precision polishing
Hi,
Very nice and clear explained👍👍👍👍👍
One Q: is there a reason why you do not use the drill bit holder on the (red) grinder?
Yes, there is a (two) reason: I dont like it very much and I sold it ;)
@@StefanGotteswinter
Ok, good reasons 😁
Hallo
Do you know how these cooling holes wer made into the carbide drills?
And what is the name of this measuring tool? 16:30
Very exciting informative Viedeos really like to watch them.
love that grinder! Can you name the diamond wheel please?
How about "Wheely McWheelface"?
I quite often split the point on hss drills by hand, it's not any harder than doing a nice job of hand sharpening a drill bit in the first place. It makes a massive difference when it's necessary to drill harder steels with a cordless drill and also drastically reduces z feed pressure in cnc's which for larger twist drills is usually the limiting factor.
As for reliability, hss drills in hard structural steel do tend to fail around the relief in the centre first. In softer steel reliability isn't an issue.
I also use a lot of carbide insert drills, which have the same geometry as what you have done. When they are run at the reccomended settings in a cnc, they tend to wear very evenly and are crazy fast. The expensive failures I've seen appear to have been failures of the cutting edge not the Web.
One other thing, if/when a split point drill fails, you tend to have to remove more material from the drill to resharpen it.
"a very harmonic experience" lol
Thank you for stressing dust extraction. I grind presintered carbide and can see what it does to machines and my mask.
will all this fit in my toolbox?