Barry Smith 4 | 22/04/2022 12:43:56 |
![]() 29 forum posts 2 photos | Hi, does any have experience they can share on hi speed bench drills particularly modern (proxon) vs traditional Pollard/Herbert ie old proper drill presses. I will be using it to supliment my belt drive bridgeport which has, like me seen better days when used at high speed. thanks Barry |
lfoggy | 22/04/2022 15:33:22 |
![]() 231 forum posts 5 photos | What speeds and what size drills are you looking for? I have a modern Amercian made Cameron model 214 drill press with a speed range of 1000 - 30,000 rpm that I use for my clockmaking. Its an excellent machine that easily drills holes down to 0.3mm. Cameron claim you can go smaller than this but have not tested this myself. Not much use for anything above 2mm though. |
John Haine | 22/04/2022 16:57:02 |
5563 forum posts 322 photos | There's a little Proxxon drill press which is best avoided. |
AJAX | 22/04/2022 17:05:10 |
433 forum posts 42 photos | We have about 6 of those little Proxxon drill presses for PCBs. Some are mains powered, others use a brick adapter. I don't particularly recommend them. The chucks are low quality and there is a lot of slop in the mechanisms. |
AJAX | 22/04/2022 17:05:49 |
433 forum posts 42 photos | Posted by Barry Smith 4 on 22/04/2022 12:43:56:
Hi, does any have experience they can share on hi speed bench drills particularly modern (proxon) vs traditional Pollard/Herbert ie old proper drill presses. I will be using it to supliment my belt drive bridgeport which has, like me seen better days when used at high speed. thanks Barry How "high speed" do you need? |
Brian G | 22/04/2022 17:26:21 |
912 forum posts 40 photos | I have a Proxxon TBM220 which has three speeds - 1,800, 4,700 and 8,500 RPM, although to be honest I have never needed to use its top speed. Using the included collets (which don't go below 1mm) isn't very convenient, but the nose is threaded 3/8" to take a 0.5-6 mm screw-on chuck, and Proxxon sell a decent Rohm chuck for it. (I also have a 10mm Rohm chuck which would theoretically let me drill 10mm holes in aluminium on the slowest speed, but it seems a bit unkind on a tiny machine with an 85W motor to try this.) As a comparison, it seems to be at least as rigid as my Unimat SL in drill mode (both are more than rigid enough for small drills), and can go faster than the Unimat's 6,000 RPM. Brian G |
Barry Smith 4 | 22/04/2022 18:07:25 |
![]() 29 forum posts 2 photos | Thanks for these useful comments looking to be able to use in the range 3000 to 8000 for sub m3 holes in alloy and steel. I have been making do with my bridgeport with belt drive head but it does not like going more than 2,000 rpm, or at least my ears don't like it. Ideally a high speed head for my F3 Aceria would be nice, but almost impossible to find, hence deciding to look at alternatives solutions. I do like old iron, but just a little concerned wrt wear on the spindle bearings but I guess that means trying before buying, which is a good maxim. Barry |
bernard towers | 22/04/2022 18:55:43 |
1221 forum posts 161 photos | Could you fit a elf powered drill head to the Bridgeport that way you still have X and Y movement? |
not done it yet | 22/04/2022 20:20:28 |
7517 forum posts 20 photos | Posted by bernard towers on 22/04/2022 18:55:44:
Could you fit a elf powered drill head to the Bridgeport that way you still have X and Y movement? Bernard, How much is one ‘elf power’, compared to Brian G’s 85W Proxxon?🙂 |
Brian G | 22/04/2022 20:39:05 |
912 forum posts 40 photos | Posted by bernard towers on 22/04/2022 18:55:44:
Could you fit a elf powered drill head to the Bridgeport that way you still have X and Y movement? Or possibly an epicyclic speed increaser like the one offered by Hemingway Kits, that would give you up to 6,000 RPM without running the mill beyond 2,000? Brian G |
Mike Poole | 22/04/2022 21:31:28 |
![]() 3676 forum posts 82 photos | A sensitive feed is an important part of a high speed drilling spindle, sub millimetre drills need a high speed and sensitive feel to avoid breakage, the sensitive feel is probably more important than the optimum speed which can reach extremely high levels for non ferrous materials. Mike |
bernard towers | 22/04/2022 23:58:02 |
1221 forum posts 161 photos | Problem with the hem speed increaser is its reverse rotation, but I have some half finished drawings for one that travels in the right direction, watch this space!! |
Barry Smith 4 | 23/04/2022 10:52:31 |
![]() 29 forum posts 2 photos | Thanks all very useful. As always the requirements expand as thinking if I go down the speed increaser / self powered route I might include some milling with small end mills. So I need to steer away from chucks. I have seen some planetary speed increasers with two 10mm shafts for less than £40 but not sure re bearings and what the tir would be when fitted with an er chuck. Obviously the main gearbox would have to be located as per the hemingway kits model. Not too concerned re reversing as all my Mills are on vfds. Barry |
Dave Halford | 23/04/2022 12:12:50 |
2536 forum posts 24 photos | As Mike mentions, the beauty of a proper high speed drill is that you can drill small holes with the pressure of one finger. If your Bridgeport quill lever delivers that OK, if not then you buy a lot more small drills. |
steamdave | 23/04/2022 12:49:45 |
526 forum posts 45 photos | Posted by Mike Poole on 22/04/2022 21:31:28:
A sensitive feed is an important part of a high speed drilling spindle, sub millimetre drills need a high speed and sensitive feel to avoid breakage, the sensitive feel is probably more important than the optimum speed which can reach extremely high levels for non ferrous materials. Mike Chuck Fellows (RIP) described a small sensitive drill table and I based mine on his design. It uses a linear bearing for the vertical slide. The screw holes are spaced to accept a Myford vice and extra counterweights are available to maintain a neutral balance. It mounts on the milling machine table or in the main vice easily. It may not suit Barry's requirements for the high speed but Mike mentioned a very valid point about sensitivity. Dave Edited By steamdave on 23/04/2022 12:50:15 Edited By steamdave on 23/04/2022 12:51:13 |
bernard towers | 23/04/2022 13:16:06 |
1221 forum posts 161 photos | That’s really nice Dave. |
ega | 23/04/2022 14:45:51 |
2805 forum posts 219 photos | steamdave: When I saw your drill table I immediately thought that it could be incorporated into GHT's UPT instead of the original minidrill design. Can you point me to details of your own or Chuck Fellows design, please? |
steamdave | 23/04/2022 17:13:18 |
526 forum posts 45 photos | ega Send me a private message with your email address and I'll send you all the info. There is too much to put here. Dave |
Barry Smith 4 | 23/04/2022 18:24:28 |
![]() 29 forum posts 2 photos | Steamdave, very nice and a good solution to part of my conundrum. Just need to look at getting the spindle speeds up. Barry |
Rod Renshaw | 23/04/2022 18:53:11 |
438 forum posts 2 photos | The points about sensitivity are well made but I sometimes wonder if we worry too much about speed. Clearly someone wanting to make 10,000 very small widgets an hour on an automatic machine needs to consult tables of optimum speeds but for less demanding requirements less speed may not be a big problem. Think of those traditional watch and clockmakers and their bob drills and bow drills and Archimedian drills. One would need to be some sort of athlete to get more than a few hundred RPM with any of those. In one of the early MEs a highly respected author wrote there is "no speed too slow to get a good finish or a true hole, it just takes a little longer." So if one only needs a few small holes, and has a machine that does not wobble, has a concentric chuck or collet, reasonable bearings and a sensitive feed, and is not impatient or ham-fisted then small holes are not a problem. I don't know about anyone else but I find the setting up of the machine, the marking out of the job, the clamping and general alignment of the work all take a lot longer than the comparatively few moments that the actual drilling takes, I do like the rising table idea for small holes on a big machine. perhaps the design could be written up for MEW? I have a traditional sensitive drill of the Edgar Westbury type which I bought from a forum member who had made it himself from a set of castings and was giving up due to age and ill health. it has done me well for small holes down to about 0.5mm despite not going more than about 2,000 RPM on the fastest of it's 3 speeds. Rod
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