Using a pillar drill for milling?
larry phelan 1 | 26/06/2019 09:32:56 |
1346 forum posts 15 photos | I never thought that one could cut gears with a B&D drill ! Just goes to show what some of these old timers could do ! |
Nigel Graham 2 | 26/06/2019 09:43:09 |
3293 forum posts 112 photos | Y4es,. we can only admire the quality many of them achieved with very basic equipment. For decades they were doing well to have a treadle-driven Drummond lathe (which was quite a versatile machine), a hand-operated bench-drill and hand-operated grinder. Early-20C Model Engineer & Electrician as it then was, is a treasure-trove of ingenuity - I've seen in one copy, even how to re-seat a kitchen tap before the days of tap re-seating tools. (On the lathe, of course.) |
SillyOldDuffer | 26/06/2019 10:18:56 |
10668 forum posts 2415 photos | Some pictures may help. These are of an ER32 collet chuck with an MT shank. ER32 is probably the most popular because of the range of collets it can hold 2-22mm. The chuck plugs into the spindle:
And is clamped in position by a 'drawbar' - a long bolt, tightened at the top of the spindle. Nipped rather than tightened enthusiastically. In this simple system, the collet chuck is released by slackening the drawbar a couple of turns and then tapping it with a soft faced hammer. (I use an ordinary hammer and a bit of Aluminium as a cushion.) In bits: Most of my milling is done with ER32 collets because they conveniently take drills, cutters and anything else with a parallel shank like my slitting saw set. My collets are metric which makes them a tad awkward to use with some imperial diameters (more tightening than I'm comfortable with), so I have a Jacobs drill chuck as well. When a lot of different sized holes are needed the Jacobs is worth having because it's quicker changing drills than a collet system. When maximum space, rigidity &/or accuracy is wanted during cutting, it's advantageous to plug tools directly into the spindle rather than via a chuck. Fly cutting and boring are my main tasks where a chuck isn't suitable. Much depends on what you're doing, but I guess most hobbyists do most milling with ER collets. Dave
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Chris V | 26/06/2019 14:22:20 |
![]() 313 forum posts 42 photos | Oh this forum is like gold dust, thank you. Nigel, ok I see a way forward then. move my Startrite drill into my woodworkshop so I have the height to drill holes in tall bits. Get a mill that dosen't have a round column and put in my engineering workshop, there isnt room on the bench (or otherwise)for both. Get the biggest mill I can, but I have max headroom off the bench (sloping roof) of 37.5"/ 950mm. The above idea is I'm sure not ideal but it might be my best option.... Just to cover all bases, is a jig borer designed for milling? They look like they're built like tanks but maybe designed more for drilling? So I had a look at Eurotrade, then looked up where Seig are made )-: I would MUCH rather buy British if I can. I found Cowells which look great but no doubt you'd say too small for general model engineering? I see Myfords made one also but expect that would bee too tall even if I could track one down. Any suggestions of a mill made in the UK? Many many thanks Chris. |
Chris V | 26/06/2019 14:34:57 |
![]() 313 forum posts 42 photos | Thank you not done it yet, yes I figured there would likely be a compromise somewhere along the line, appreciate you point out what it is. I'm thinking buy a mill in due course to replace the drill, but put the drill in my other workshop. Its not i'm sure ideal but at least then I'd have the height available to drill holes at least. Out of interest what make of mills do you have? In due course I'd much rather buy British if I can, even if it has to be second hand.... Cheers Chris. |
Chris V | 26/06/2019 14:44:21 |
![]() 313 forum posts 42 photos | Hi Silly Old Duffer and thank you. I just looked online and at least I dont think I made a mistake buying the ER20 collet set, I dont think the ER32's are available on a 1MT, that would fit my lathe. Actually I have a Tyme Cub woodworking lathe also that they fit, I do my freehand brass turning on this, and cutting threads using taps & dies. But now at least I know a little more of the various types and can take that into consideration when considering Mills. Cheers Chris. |
Neil Wyatt | 26/06/2019 18:21:29 |
![]() 19226 forum posts 749 photos 86 articles | Posted by Chris Vickers on 26/06/2019 14:22:20:
So I had a look at Eurotrade, then looked up where Seig are made )-: I would MUCH rather buy British if I can. I found Cowells which look great but no doubt you'd say too small for general model engineering? I see Myfords made one also but expect that would bee too tall even if I could track one down. Don't buy a Myford VMB then - they were made in Taiwan. Neil |
SillyOldDuffer | 26/06/2019 19:01:00 |
10668 forum posts 2415 photos | Posted by Chris Vickers on 26/06/2019 14:34:57:
... Out of interest what make of mills do you have? In due course I'd much rather buy British if I can, even if it has to be second hand.... Cheers Chris. Offhand I can't think of a British made manual mill in current production apart from the Cowells, which would be too small for me. Second-hand there's more choice, but they tend to be big - sold to users with more space and money than the average Joe. Adcock and Shipley made a clone of the popular USA Bridgeport, which is a shade too big for the space I have (single garage). Have a look at the excellent lathes.co.uk. I think you'll find there's not much going smaller than a Bridgeport. (I expect someone knows better!) Over the past 30 years Industry & Education have largely walked away from manual lathes and mills in favour of CNC. New British made machine tools are pretty much way too expensive for amateurs; high-end stuff, not aimed at men in sheds! Quite a lot of good second-hand about but be careful: condition is everything. Spares can be hard to find and/or amazing expensive. You mentioned Jig Borers in an earlier post. These are a type of smallish milling machine made specially to deliver high-accuracy for tool-making. Very desirable if you can find one in good nick, but likely to be costly. Also, a clapped out jig-borer is clapped out! To get started I bought Chinese; much more choice. Dave
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Former Member | 26/06/2019 19:55:47 |
1329 forum posts | [This posting has been removed] |
Nigel Graham 2 | 26/06/2019 20:36:13 |
3293 forum posts 112 photos | I'm afraid you won't find a reasonably -sized milling-machine made in the UK now. My own is a Myford VMC, but that was made in Far East and Myford no longer make them, unfortunately, Inaccurately described by Myford itself as a "turret" mill, it stands roughly 6 feet high with its belt-cover open. That's on its proper stand. it's decent-size machine that will handle most model-engineering and similar projects easily. Most except the smallest milling machines are made to fit on a purpose-made stand, not on an ordinary bench, as that's not rigid enough, though the stand is often offered as an extra .. They do a need a good rigid base. My present workshop has a concrete slab floor, which is ideal; but my previous was an ordinary wooden shed which I lined for insulation. To stabilise the milling-machine I had then, a Warco " mill/drill " on a substantial frame made by its previous owner, I cut 4 holes in the timber floor and cemented brick pads to the concrete foundation, with interposed plastic discs to act as " damp-proof courses ". A lot of stuff coming from the Far East is of doubtful quality, but the main model-engineering suppliers in this country are careful to import the better machines. You may need to carry out quite a bit of setting-up, starting with cleaning off thick antic-corrosion goo, but the importers will tell you how to go about it. ' To amplify Dave's comments, a Jig Borer proper is a large, very highly specialist machine but the sort you and I are most likely to encounter (and I own one) is the compact but massively-built BCA, sold by Tenga Engineering. It's not really a "jig-borer" by principle, but is a small, precision vertical-mill whose long-travel table is basically also a rotary-table; but " long " is relative here: under 8 inches I think. Its main use for us would be making very small components with a lot of radius-based features. For most purposes a conventional vertical milling-machine, on which you can mount a rotary table anyway, will be much the better choice; and will handle those very small components easily. ' So your best route is 1) Decide what sort of projects attract you, to gain an idea of the sizes of their largest components hence the machine capacity needed. Note that table size is usually smaller than travel. 2) Examine what's on offer, new or second-hand; but note Dave's comments on condition and spares availability; with reference to Point 1) as well what fits your workshop. 3) Again from 1), determine what tooling you will need to hold milling-cutters and a drill-chuck to start with. You can add nice things to have, like a boring-head, later. Also what work-holding. A drill-vice is not suitable for milling as it is too lightly made, but there's no reason you can't use a milling-machine vice on a pillar drill if it fits the table. A milling-vice is a precision-tool with a hefty body sliding usually on dove-tails, as it has to carry heavy lateral loads, and the larger sizes are very lumpy beasts. First and foremost though is a clamping-set with T-nuts and studs appropriate to the machine - and you will soon find you can never have too many clamps! Harold Hall's Milling book (Workshop Practice series) has a lot of advice on safe work-holding. You can add angle-plates, a rotary table etc. later. but these greatly enhance the range of operations possible.
It will be worth your finding someone who can traipse around a major exhibition to examine machine-tools with you... though I gather one of the largest suppliers, Warco, has announced it is no longer attending the shows. (BTW... your drill, is it a Pillar drill, or a Bench drill? The difference is simply that the Pillar Drill's column is very much higher, rising from a heavy base that must be bolted to a flat, level and solid floor. The Bench drill has a fairly low column and is made to be bolted to a rigid bench; even if the head is identical to that on the same maker's equivalent pillar-drill. The advantage of the pillar-drill is much greater height-range for the work.) ' Finally I think you asked about lathe change-wheels. Yes, they are for fine feeds as well as screw-cutting, depending on the range of wheels your lathe has. Books on turning detail the calculations, but I can show the principle by example. Say your lathe's lead-screw has a lead (= travel of the saddle per revolution) of 1/8 inch. If you connect the spindle to the lead-screw by gears of overall ratio 1:1, one turn of the spindle will turn the lead-screw 1/8 " so moving the saddle 1/8 ". For cutting an 8 tpi thread (tpi = threads per inch). Double the ratio denominator to 1:2, the lead-screw rotates half a turn, the saddle moves 1/16 " - a 16tpi thread. 1:4 = gives 1/4 of the lead, 1/32 " travel: 32tpi (a standard Model Engineering Thread-count). And so on. Eventually, with a compound gear-train, the lead-screw turn is such a small fraction per turn of the spindle that it moves the saddle only a few " thou " per spindle revolution, giving a good though not necessarily satin-sheen finish (assuming all else being just so!). I think the finest listed on my Myford 7's change-wheel chart is 0.004 " per spindle rev. This probably matches a lot of reasonable trade turning where the surface is be tidy but not critical to function. ( Lathes don't like being over-driven to cut, say, a 4tpi thread, by the way.)
Eventually, assuming you have the change-wheel |
Chris V | 27/06/2019 09:08:04 |
![]() 313 forum posts 42 photos | Thanks Neil, oh ok, add that to the rest of the stuff I didnt know! (-: Cheers Chris. |
Chris V | 27/06/2019 09:10:44 |
![]() 313 forum posts 42 photos | Thank you Bill & Silly Old Duffer, seems like I'll have little choice but to go Chinese, still think its a shame though. Cheers Chris. |
Chris V | 27/06/2019 09:34:24 |
![]() 313 forum posts 42 photos | Thank you Nigel G2. Well if I want one it looks like it will be imported and small, I only have one available place for it and that's at one end of my workbench. Whist the bench is substantial I take on what you say about rigidity etc but I'm restricted to the bench only. My drill is a bench top model. Yes I had looked at the BCA's and agree it sounds like its not ideal for me. Yes I was looking at Warco's offerings, I could get to their showroom ok to see first them hand. Looks like machine size will more determine what I can and cannot take on to mill, but I have to start somewhere. Having a modest capability rather than none will help guide me as to what I want to end up machining, most likely stationary engine kit/s. I wont be rushing into buying that's for sure. So I had to look up what DRO meant, ....as its available on new machines is it now considered a must have? That said I didn't want digital calipers as I knew the batteries would run out and they would likely go wrong...Well I was right but that, but I'm so grateful I can see the display to read what I'm measuring!!!! (-: So maybe the same holds true for DRO? Cheers Chris. |
Former Member | 27/06/2019 09:43:30 |
1329 forum posts | [This posting has been removed] |
Chris V | 27/06/2019 11:15:47 |
![]() 313 forum posts 42 photos | Regarding the milling, also metric or imperial??? I'd probably find metric easier to get my head around than fractions of an inch, but would be interested in your thoughts? Cheers Chris. |
Nicholas Farr | 27/06/2019 11:47:10 |
![]() 3988 forum posts 1799 photos | Hi Chris, something you can only answer yourself really, and if your not that good at imperial measuring, I would think is easy to solve. Regards Nick. |
SillyOldDuffer | 27/06/2019 12:38:48 |
10668 forum posts 2415 photos | Posted by Chris Vickers on 27/06/2019 11:15:47:
Regarding the milling, also metric or imperial??? I'd probably find metric easier to get my head around than fractions of an inch, but would be interested in your thoughts? Cheers Chris. I'm metric, partly because I have scientific interests, partly because metric is easier and less error prone because it's internally consistent and eliminates unnecessary conversions in the maths. Two main reasons I would have gone Imperial:
A third valid reason for preferring imperial is having a lifetime's experience of imperial measure. Not many youngsters in this group, unless you are an American! (And even they are gradually going metric.) The tide in the UK is running against buying stock and tools in Imperial sizes. Not a major problem yet because a lot of Imperial is still about. But, in broad terms metric tends to be cheaper and easier to find. Some older Imperial systems like Whitworth are no longer mainstream, and only available as 'New Old Stock', to special order, or is even Unobtainium. Doubly difficult to be imperial in historically metric countries. Worth putting a little thought into what your workshop is for. Far Eastern metric equipment suits me because I like learning and I mostly make metric objects. I see tools as consumables, to be used rather than cherished, Others like to celebrate traditional techniques and enjoy well-made British tools as icons. At one side of hobby are chaps embracing computers, CNC, cheap foreign tools, and experimental work (aka bodging!). At the other are chaps who making superb steam locomotives from LBSC plans with 50 year old manual lathes, where skills and quality are relished. Most of us I suspect are in the middle, mixing tools, techniques, and outputs to suit our interests and budgets. In the end, it's your hobby, so spend money on what you want. My main regret is not getting stuck in earlier due to indecisiveness. Too much conflicting advice! Eventually I realised that flashing some cash on Far Eastern kit (a mini-lathe) would get me started with minimum bother. Not the best of all possible lathes, but I had lots of fun and learned a great deal from it. For me, cutting metal today is more important than setting up a top-end workshop in the distant future. I'm messy, care minimally about finish, and potter. I will never win any medals! What's your intent and ambition? Dave |
not done it yet | 27/06/2019 13:17:28 |
7517 forum posts 20 photos | Hi Chris, My mills are old - 1960s. A centec 2B and a Raglan. The Centec can be used for either horizontal or vertical milling, so is quite a popular model among hobbyists, but certainly not a light machine. |
Nigel Graham 2 | 27/06/2019 13:52:22 |
3293 forum posts 112 photos | I owned a Centec 2B for a while, even fitted it with a raising-block from Tony Griffiths. "... not a light machine.. " in weight, I agree. It is a good little machine, and it will fit on a strong bench, but its capacity is quite small. If I were looking for anything similar now, I think I'd investigate the smaller Tom Senior or equivalent mills. As it happens I have a Denbigh H4 horizontal mill, but it's quite basic and not designed to take a vertical head. I think people have made such heads for similar machines, but it's a lot of work and the base machine's flowing curves don't exactly help. |
Chris V | 27/06/2019 16:34:20 |
![]() 313 forum posts 42 photos | Thank you Nick, Dave, Not done it and NG2 I will investigate further. In terms of my work I'm used to BA, BSB & Whitworth threads, though I normally use metric drills. I find most of my raw material suppliers still supply Imperial sizes. But measuring myself anything under 1mm my metric digital calipers come into their own...referal to conversion charts for drill sizes etc is frequent. My lathe the old Myford ML1 was bought on grounds of size, ie small, basic, and looks, I like old tools & machinery. I am gradually learning the basics of how a lathe works and what does what, not that its running yet. Before buying I was aware a ML10 or ML7 is much more sophisticated and up to date but I felt it better to start basic. Someone mentioned Drummond treadle lathes I think, I was SO tempted but being tall I figured I'd bang my knees and maybe that was a step back in time too far, oh and space was against it too, I can store stuff under the Myford. Apart from the general ability to turn steel (I hand turn brass on my wood lathe) the aim for me is to be able to make a stationary engine kit such as a Stuart Turner James Coombes. I started one years ago and put it down when self employment work took over. By started I mean I did some basic work like chain drilling and cutting out apertures in the plate steel, filing up castings and taper turned the 4 columns on my Unimat SL. Leaving the tricky stuff.... A few years back I gave it away to a relative to finish but hes not touched it so I might be able to get it back, if I don't I'd like to build something like the Polly Benson engine kit. But I don't have a mill and can see a dedicated machine would be better than trying it on my basic lathe. So I then looked at German Bengs kits, as they don't need milling, its already done. But they use metric threads of which I have very few, though I guess I could use imperial. I expect the S Turner kits specify any milling required in imperial but I don't recall? That why I asked about metric or imperial, in a nutshell Cheers Chris. |
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