Drill grinding machine
|david gregg 1||09/08/2019 21:17:49|
|7 forum posts|
I need to purchase a new drill grinding machine I would mainly grind grind drills from 5mm to 20 mm dia anything bigger I just grind by hand and anything smaller I just touch up by hand .I have previously used a Darex drill grinding machine with limited success ,but I did find it useful to get the drill lips the same length even I did have to alter clearances by and I wonder if the new Darex is an improvement on my old model,
|Mike Poole||09/08/2019 23:39:51|
2041 forum posts
I picked up a Dormer 108 for £175, it grinds drills like they left the factory. They do turn up at bargain prices but you may need to wait.
|gary shepherd||10/08/2019 05:49:40|
|56 forum posts|
a used drill doctor off ebay works for me great tool. gary
|Clive Foster||10/08/2019 09:55:41|
|1802 forum posts|
If its still available and the price isn't too silly the Kaindl BSG 20/ 2 :- https://www.kaindl.de/en/bsg-20-435.html#amfile_files seems to have a lot going for it.
I took a very good look at getting one some years back but a Clarkson attachment turned up at a price that would have been criminal to refuse. Dunno if there is a UK agent.
Basically a properly sorted version of the common swing over the wheel "too cheap to work well" devices but working vertically across the front of the wheel rather than sideways over the side. Thing I really like is that the drills carrier is reversible so once one edge is aligned the other one is too, an easy process if the instructions are to be believed. So once one edge has been sharpened the whole thing can be just flipped over to do the other edge. Drill carrier is ingenious being a proper pair of Vee blocks segmented toast rack style so anything between 2 and 20 mm can be held.
Instructions say it can also do point thinning, forstener bits and those brad point wood drills although the last two need a wheel dressed to shape which may not be practical. Ends of milling cutters can also be ground but the relief angles will e slightly curved not dead flat. How much that matters I know not.
I'm no fan of Drill Doctor and similar devices where everything happens inside so if it doesn't work properly, Drill Doctors have a reputation for being inconsistent, you can't figure out WTHIGO.
Edited By Clive Foster on 10/08/2019 09:56:31
|52 forum posts||
Seeing the picture, the carrier is the same principle as the Tormek drill sharpening attachment. The Tormek one is also worth looking at to see if it meets your needs. You can buy the attachment separately from the grinder.
|Gary Wooding||10/08/2019 11:30:45|
|572 forum posts|
Take a look at **THIS** It works fine for me, and at about £50 is difficult to fault.
|larry phelan 1||10/08/2019 11:44:20|
|481 forum posts|
Like Gary, I bought a simple unit made by Martex, driven by a hand drill which works very well.
Setting and operation are much the same and the results are quite good enough for my needs.
Anything is better than a box full of blunt drills
Not "Top-of-the-range", but for the price, not too bad.
|John MC||10/08/2019 11:52:54|
173 forum posts
I would recommend one of these,
Not cheap, I shopped around and found the same machine for ~£200 less.
In the past I've used a Draper attachment, looks cheap and nasty but works remarkably well. Also a Martek and a Drill Doctor, both hopeless. Ok for getting an even point but both failed to give any clearance, needed to do that off hand.
There was a recent thread about drill sharpening that encouraged me to have another go with the Drill Doctor, same result, even length cutting edges, no clearance!
Perhaps somebody out there wants it, they might have more luck with it than me.
|Clive Foster||10/08/2019 12:17:39|
|1802 forum posts|
The Tormek system looks well thought out too but its limited to four facet style grinds and is said to be slow. Appears to be best used with a woodworkers style wet wheel dipping into water. I'll bet it puts an awesome finish on the drill tho'. Around £200 I think which at first sight seems bit costly but if just works not too bad a deal assuming you have a suitable grinder.
I too had a Martex pistol drill driven device once. Fairly early one so they may have got better over the years. This was cheap, flimsy flexi plastic without proper shaft bearings. Worked, sort of, when it felt like it. I wasted some time trying to engineer repeatability in before launching into orbit (metaphorically speaking).
Sealey device looks good in principle but, when I had crawl over one, it seemed yet another "made too cheap" device. Drill holder and alignment devices seem on the flimsy side and you are totally reliant on the wheel holding its shape.
I've had far too many drill grinding device through my hands. Either personal purchases or "help a friend get it working" services. My experience has been that the inexpensive ones can be got to work for a while but you do have to be careful. For hobby guy who may sharpen 50 - 100 or so drills in a decade £50 (ish) and a bit of extra care may well be a good deal.
Trouble is the good, just works every time, breed are expensive. Tomek seems to set the starter price. If the market hadn't decreed that Ordinary Joe won't pay more than £50 (ish) even if "some frustration involved" there might be more market room for better devices given the usual mass production price drop. I can't see why the business end of the Kaindl i.e. drill carrier, post and slide couldn't be sold for under £100 as a bring your own grinder device.
Edited By Clive Foster on 10/08/2019 12:18:44
810 forum posts
I suspect you're after a larger machine than I have space or funds, but these two threads might be of interest
Both are related to the Sealey or equivalent and the swing past the wheel type.
The Reliance seems to work OK and it available in three sizes, though I don't think I've seen the biggest on on ebay.
There's lots of info on the web about the Picador and the far eastern ones which are of a similar design but slightly different geometry. The Picador seems to work out of the box, but the others seem to need work to get them to function. See Mr Meek's articles
|brian curd||10/08/2019 12:42:43|
|102 forum posts|
I Have A Drill Doctor 700. After a quick read of the instructions I sharpened a set of drills plus some Morse taper ones up to 3/4" with two failures . Replacing the offending articles back into the machine resulted I success. I ignore the "turn it an equal number of turns " instructions and after setting the end stop to the minimum position continue sharpening until their is no more sharpening noise . Split points are very easy . The critical bit is setting the drill in the correct position and making sure that it does not move when the chuck is tightened .
|gary shepherd||10/08/2019 14:56:38|
|56 forum posts|
you hit the nail in the head there brian, read the instructions. to many people willing to critise products without sdudying the instructions, they expect the tool to work perfectly every time with very little input from themselves. gary
|John MC||10/08/2019 16:45:12|
173 forum posts
The last two posts, should we ignore or follow the instructions! I (and others) have taken both approaches, still doesn't work. My 20 year old (I think) version of the Drill doctor was notorious for variable results, newer versions seem better. It was the second one I had, first one returned to the supplier, really should have sent second back but never got around to it. Anyone want it, free to a good home......
Edited By John MC on 10/08/2019 16:51:50
|brian curd||10/08/2019 16:57:50|
|102 forum posts|
I chose to use the 'Grind it until is stops' approach because the 'equal number of turn' method assumes that the original cutting edges were correct , if blunt. Setting the end stop on 700 restricts the amount that can be removed and ensures that ,in the end, the two faces are as close to the same as the machine is capable off. As I said, the only problem that I have found is that after turning the drill until the flutes meet the clamping system it tends to twist as the chuck is tightened . This certainly messes up the relief angle
|brian curd||10/08/2019 18:12:00|
|102 forum posts|
I have sent you a PM
|Mick B1||10/08/2019 19:29:43|
|1151 forum posts|
I bought a little Parkside drill sharpener at Lidl - IIRC you set the lip of the drill against a datum edge, then apply the drill to a diamond-coated wheel in a fixture.
It's not that it doesn't work. It does, if you set everything right and inspect what you've done between setting and grinding.
But frankly, it just sits on the shelf, 'cos it seems more trouble than it's worth. I learned to grind drills offhand as part of my Government Training Centre Lathe course in 1975, along with about 20 others. Most of us spent most of a day getting our angles and lip lengths right enough to drill holes within a thou or so of size and with more-or-less even chip flow from both lips.
There was nothing special about this - it was a standard expectation that you'd routinely sharpen your own drills with nothing more than a bench grinder plus a couple of basic measuring tools, like a good pocket rule and maybe an angle gauge if you really needed it.
I've done the same ever since. I'm struggling to understand what a drill-sharpening fixture or machine would really do for me.
|david gregg 1||10/08/2019 20:15:04|
|7 forum posts|
Thanks to all those who posted a reply ,I can only say there is such a lot of confusion about suitable drill grinding machines .The man who found the Dormer 108 for the ridiculous price is a lucky man .The motor has burnt out on the Darex which I have at present and I only had inconsistent results ,good for getting the lips both equal but the clearance often had to be altered freehand .I have sent an enquiry to Kanidal about there machine ,but it may be to expensive so thanks to all
|Speedy Builder5||10/08/2019 20:27:37|
|1800 forum posts|
Kaindle also make a similar machine for sharpening end mills, it would be great if the same machine did both drills and end mills.
|Clive Foster||10/08/2019 20:53:51|
|1802 forum posts|
The Parkside drill sharpener you got from LiDL is a "not quite right" copy of the original Plasplugs device. I have one of the Plasplugs one which works very well indeed. Blooming miracle for (mostly) flexi plastics construction.
As you found out the LiDL one generally doesn't behave unless you invest silly amounts of care in set-up and even then its a bit hit or miss. Basic inspection of the one I bought for a friend doesn't show any obvious reason why it doesn't behave although I'm less than sanguine about those "plated on to a sheet steel former" grinding wheels. If anything the plastic and moulding quality are a touch better than Plasplugs. So glad that I checked the LiDL one before a 40 mile round trip to drop it off. Even though I now have yet another shelf filler.
Totally agree that a drill sharpener should just work without faffing around and / or "interpreting" the instructions. The only acceptable process should be :-
1) Insert in carrier. 2) align by simple line or better fixed abutment for right every time. 3) Zzzipp, sharpen one edge. 4) Flip, Zip sharpen the other one. 5) Inspect and if not quite sharp adjust cut by simple screw then repeat steps 3 and 4.
That should be it every time for a simple conical or 4 facet point. Point thinning should be just as easy.
If its not just like that, right every time there is hardly any point to a jig. Although I will admit to sticking up blunt drills for a session with the Picador device. Mostly 'cos it always seemed to take a couple or three to get my eye in.
|Andrew Tinsley||10/08/2019 21:42:14|
|911 forum posts|
Yes I have a Plasplugs device and I am amazed how well it works. As Clive says it is a plastic unit and quite flimsy, but it does the job of sharpening remarkable well. As long as you take care to get both edges the same length, then I can't fault it.
Please login to post a reply.
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.
Click THIS LINK for full contact details.
For subscription issues please see THIS LINK.