# Couple of metalworking questions.



## skipdiver (21 Oct 2017)

Firstly, i need to cut a 5 or 6mm wide slot, about 75mm long in a piece of ali tube, which is 16g, or 1.6mm thick. Obviously a milling machine would do the trick but i don't have one, so is there another safe method to achieve this? Thinking it could be done with my router and a suitable bit or maybe in the drill press with a milling cutter somehow. Any pointers appreciated.

Secondly, i need to produce some small parts from stainless steel rod of 3mm and 4mm diameter. What's the best way to cut and finish the ends, which will need to be rounded over slightly, so they are not sharp. What grade is best to work and can i simply dress the ends on my bench grinder or will that be too rough? 

Not worked with metals much in the past and am on a steep learning curve.


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## Rorschach (21 Oct 2017)

Drill each end of the slot in the drill press and then saw and file out the rest. If it's only a one off it won't be too much hassle.


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## skipdiver (21 Oct 2017)

Rorschach":1rwlh98b said:


> Drill each end of the slot in the drill press and then saw and file out the rest. If it's only a one off it won't be too much hassle.



I need to do quite a few and quite regularly, so looking for something more efficient.


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## AES (21 Oct 2017)

You could make up a small jig (just wood/MDF, nothing too complicated) to hold both the tube and a Dremel-type tool fitted with a cut-off disc of the correct thickness - if you don't go for the modern "Click-Twist" type mandrel, but the old screw-type mandrel, cut off discs are available in various thicknesses (the modern type mandrel only holds the thinnest discs). At worst case you'd have to do the slots in 2 or 3 passes (in width) as I doubt Dremel anyway have cut-off discs quite so thick.

For the jig, have a look on here for a post by Dalboy in the Projects section, where he describes making a superb scale model of a WWII half track truck. There's a jig for doing the wheels fo that in his post and something a bit like that, though not so complex, would work well I think.

Also, if you go for a mains Dremel, I must say that I love mine - I've heard several moans about Dremel here, but I THINK they refer mostly to the new, battery models. Proxxon is another good buy I've heard (though here, they're more expensive than Dremel, hence me owning Dremel) Though from time to time, Aldi have a cheapo version on sale too. Clearly not so good as Dremel (my Aldi isn't any way, it runs very rough compared to the Dremel), but that would also do the job, and all the mandrels, etc, are interchangeable between makes if you use the chuck model, NOT the collet model.

For your SS rod pieces, I'm assuming you have no lathe? If not, then cut off to length as accurately as needed (32 TPI hack saw blade, or cut-off disc as above) then mount them in a rotating chuck (electric drill in bench holder, or better, in a drill press) then just use a smooth single cut file to smooth/round off the ends (see my bit on Files & Filing) - sorry, no self-promotion allowed!!

Seriously, you may mess up the first 1 or 2 SS rods, but you'll soon get the hang of it.

HTH

AES


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## skipdiver (21 Oct 2017)

Cheers AES, much food for thought there. I have a Dremel somewhere that i have never used and had forgotten about until you mentioned one, so that's do-able. Also have a drill press and lots of files i inherited when i bought my house and found them all in the shed. Apparently the guy who lived here before i bought the house made model boats and had lot's of gear which his family sold, but they left a box of bits under the bench containing the files. I will have a root through and see what's what.


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## J-G (21 Oct 2017)

skipdiver":aw0ceihr said:


> I need to do quite a few and quite regularly, so looking for something more efficient.


That is the killer statement.

I've been watching both your threads and find some of the advice given to be seriously 'suspect'. Yes, I'm sure you could do the odd 'one-off' of all of the items you've mentioned by the methods suggested but I'm equally sure that you would very soon be dis-satisfied with both the quality of the items you produce and the time it takes. There is also a serious issue of safety if you use milling cutters in pillar drills - they are not designed for 'lateral' forces and the chance of the chuck detaching itself from the quill is very high - I speak from experience!!

Similarly, using a router free-hand - even guided with a jig - is akin to an accident waiting to happen. Although Ali dose need relatively high speed for best finish (on my mill I work at about 12-1500), routers are far too fast, generally starting at about 3k.

I still think that an investment in a small lathe is your best solution. No. it's not a milling machine but it is possible to do some milling operations on a lathe - just by thinking 'outside-the-box'. The work-piece doesn't _*have*_ to be in the chuck/collet, it can be mounted on the cross-slide - with a suitable jig (which you would have to make of course) - and the cutter can be held in the chuck/collet. I did a great deal of milling work like this on my Myford 7 before I bought the Warco Mill.

The slot in your ali tube is the particular project I'm thinking of here - though you haven't said how long the tube is so I am making certain assumptions that it is short enough to be accommodated in your workshop. The Warco web-site doesn't specify the travel for the cross-slide but since the Osaki is a smaller spec and has 65mm, I suspect that you could anticipate the 70mm you would need to cut a 75mm long slot 5mm wide. It would be better to have a margin of error of course and is a question to ask of Warco.

As far as Stainless Steel is concerned, as long as the environment for the component is not 'Marine' then either 303 or 304 would be easier to machine than 316 but whether running them on a grinder would surfice is down to what sort of 'finish' you want. In a lathe with a collet chuck, you could very easily 'dome' or just chamfer the end of a bar, part off, do the next until the batch needed is complete then re-mount each for a second operation on the other end, producing a quality product.


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## skipdiver (21 Oct 2017)

Thanks again J-G. I do want to do things properly and safely. If that means buying a small lathe, then that is what i will do. I've spent my whole life working with wood and am always safety conscious when using machinery, but all things metal are a steep learning curve for me. I didn't take to metalwork at school and have steered clear of it since, as i have no interest in it. However, needs must now, so i will have to learn.


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## AES (21 Oct 2017)

J-G's quite right about a lathe of course, BUT unless you're making literally thousands off, bearing in mind your previous dislike of metal working, AND the budget (for even a simple set up reckon on double the cost of the machine itself - unless you get really lucky buying SH) I wonder if you're not approaching this in too complex a manner?

J-G's right about using a router (IMO - I don't like either the safety aspects or the high rpm), but without beating my own drum, I believe the set up I suggested with cut-off discs in a Dremel will do the job nicely if you make the jig accurately. And frankly, the idea of employing a lathe "just" to make nice domed ends on SS rod of 5 mm dia is sheer extravagance (financially) and overkill technically. Yes, of course a lathe will do a nice job on those rod ends (IF you have one), but you could soon learn to use a file and do without - IMO anyway, FWIW.

AES


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## skipdiver (21 Oct 2017)

Thanks again AES. That's the dilemma for me. Although not one off's , i only require about 20 or 30 pieces every few months. Maybe a hundred a year, if that. 

I am in the market for a new pillar drill, so is there such a beast as a combined mill/drill that can be used for metalwork and woodwork?


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## Rorschach (21 Oct 2017)

You can indeed buy round column Mill/Drills and I think one would be very well suited to your job here.


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## skipdiver (21 Oct 2017)

Then that may be the way forward. Will have to do a bit more research.

Is the mention of a round column significant?


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## Rorschach (21 Oct 2017)

Yes, round column mills are much cheaper than knee/square column mills, they are also not as rigid. This limits the size of cutters and depth of cut they can take, that's why they are marketed as mill/drills. They are sold as heavy duty drills that can handle light duty milling. In practise however they are capable of good work if you take your time and work within their capacity, for instance using smaller cutters and taking multiple passes and using fly cutters instead of facemills etc. For the job you suggest that sounds like it falls right within the capacity of this kind of machine and the advantage also being that they are more portable and take up less space than a large knee mill.
If you might have use for a metal working lathe though, consider a small lathe with a milling attachment, simple slot work is very easy to do on a lathe and you will find that combination a lot more versatile than a mill, also taking up less space on the bench.


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## skipdiver (21 Oct 2017)

Thanks again and to everyone who has contributed. I now have a clearer understanding and will have a look around at my options. I have some time before i need to decide.


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## AES (21 Oct 2017)

+1 for rorsach's comments on a lathe with a simple milling attachment (I have no mill - "if ONLY SWMBO would allow me to stretch the "play toys" budget!!!). But a little milling attachment IS very handy - just as he says, PROVIDED you work within its limitations - especially rigidity.

But again, just a personal opinion, and not meaning to ramble on (again), for the relatively small quantities you mention, you'll honestly spend as much time - or even more - learning to use the lathe (and/or mill/attachment), as you will just learning to use basic hand tools with some simple little jigs.

I repeat myself ONLY because you say you don't like metal work (fair enough, no critical comment here) and I think that although a lathe (for example) is marvellous fun (if you're inclined that way), to learn to use it properly, even to make such "simple" items as domed ends, may well "drive you nuts" before you've got it.

Hand work (filing, etc) would also probably "drive you potty", but to do the small numbers you're talking about, it'll ultimately be quicker in learning curve, cheaper, and produce results which are just as satisfactory.

Right, that's more than my halfpenerth". Subject closed from me now.

But whatever you decide, good luck mate.

AES


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## skipdiver (22 Oct 2017)

There doesn't seem to be a lot out there in the round column mill/drill stakes.


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## DTR (22 Oct 2017)

I agree with the comments above. If you have no other interest in metalwork then buying a machine is probably not economical. If you _have_ to buy a machine though, then a lathe with a milling attachment (or a custom jig) will make short work of it. A lathe is also a lot more versatile than a mill, even for a woodworker.


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## skipdiver (22 Oct 2017)

Thing is, i am in the market for a new pillar drill anyway, so if i can get one that takes care of my usual wood drilling needs and also has the benefits of a small mill, then that's the best of both worlds for me. I am currently paying someone to do the tasks i want to tackle, so buying some machinery to perform the tasks will quickly pay for itself. A drill/mill seems ideal to me. 

One of my problems is limited space, so selling my pillar drill and replacing with a drill/mill won't upset my layout.


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## DTR (22 Oct 2017)

This is perhaps a moot point now given your last post, but I've just posed some photos of how it could be done on a lathe, as J-G, Rorschach and AES have suggested.

Milling cutter held in a morse taper collet in the headstock. Tube clamped to a milling attachment; the tee slot is a handy way of holding the tube a bit like a vee block. You could use a similar method with the tee slots on a milling machine table, and screw a stop block to the table to set the tube length. Note that the clamps were also home-made on the lathe: 





Cheaper alternative using an angle plate and some packing to raise the tube up to the right height. The packing could be bolted to the angle plate so that it's permanently set when needed:





After taking the above photo I realised you could go a step easier and use a bog-standard toolmaker's clamp or G-clamp on the angle plate:


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## MusicMan (22 Oct 2017)

A couple on eBay might interest you. The Warco is pretty good:

http://www.ebay.co.uk/itm/Warco-Mill-Dr ... 0005.m1851

and the Arboga is superb:

http://www.ebay.co.uk/itm/AB-Arboga-U25 ... Sw4GVZ4RxS

With a mill drill the important thing to check is the rigidity of the alignment when the head is cranked up and down. The Arboga is excellent, not sure about the Warco. A trapezoidal column Warco is fine.

Keith

Keith


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## J-G (22 Oct 2017)

skipdiver":1amoqzhi said:


> Thing is, i am in the market for a new pillar drill anyway


In that case look seriously at the Warco WM 12, 14 or 16 Mills depending upon your budget.
Not as versatile as a Lathe (You can 'Mill' on a Lathe but you can't 'Turn' on a Mill) but if the majority of the potential work is Milling and Drilling (rather than reducing Ali tube by 0.6mm !!) then these are ideal replacements. They can be fixed to your workbench and the 14/16 have floor-stands available.

They all come complete with a 13mm Jacobs chuck but no Collet Chuck. The issue about using a pillar drill for milling is mostly removed because even the Jacobs chuck is held in place with a draw-bar (so can't 'drop out') but I would still recommend buying an ER32 Collet chuck, I've found that much more stable for milling operations.

This would also remove all the concerns about having to buy a vertical slide or angle plate for a Lathe and mounting that on a cross-slide with limited travel - even the WM 12 has a 250mm travel and the others have 330mm. You will naturally need some work-holding equipment (Vice, Vee-Blocks, clamps etc.) but you may already have such which you use with your pillar drill.


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## skipdiver (22 Oct 2017)

I've been looking at the Warco stuff. The WM 12 is do-able but they only have it in imperial variant; sold out of metric. Don't really know what that means on a practical level.

Second question would be suitability for use with wood, which is still my main area of work. I imagine it would be well powerful enough to drill a 50mm hole in wood with a forstner bit for instance? Are there any other considerations when using this for wood over metal?

Also been looking at the Chester Conquest, which is a bit cheaper if anyone has any thoughts on that machine.


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## DTR (22 Oct 2017)

skipdiver":2ofosjrg said:


> I've been looking at the Warco stuff. The WM 12 is do-able but they only have it in imperial variant; sold out of metric. Don't really know what that means on a practical level.



If you're comfortable switching between systems, it means very little. I often make metric parts on my imperial machines. The size of the slot you're cutting is of course defined by the size of the cutter (slot drill) which can be either imperial or metric. If you set up stop blocks on the mill table, and set limit stops for the table itself*, you'd only have to set it up once and all your parts would come out identical. 

I don't see drilling wood being a problem as long as the speed goes high enough. Personally though I prefer not to mix wood and metal where possible. I don't like sawdust getting into my machines or swarf getting near my woodwork. Needs must, though. 

* if the machine has that facility, that is. Mine doesn't, but it's not a conventional mill.


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## skipdiver (22 Oct 2017)

I don't mind working in either metric or imperial, but am at a bit of a loss as to why these machines come in both variants. Is it the parts you fit to them, ie chucks that differ? Is it the register marks and displays that are in inches, instead of cm's?

Ideally, i wouldn't want to mix wood and metal on the same machine bit space is the issue i have. I think if i rig up a good extraction system, i can minimise cross contamination.


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## MusicMan (22 Oct 2017)

It's the lead screws for the traverse stages and maybe quill that are metric thread and indicate in metric.

Keith


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## Rorschach (22 Oct 2017)

Difference between metric and imperial will only be the dial, on a mill the leadscrews etc won't matter as long as the dial graduations are correct. Leadscrews are only important on a lathe for screwcutting.


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## skipdiver (22 Oct 2017)

Cheers chaps; steep learning curve but i'm getting there.


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## SteveF (22 Oct 2017)

that arboga is crazy money
it does have a nice table but still
I recently paid a fraction of that

Steve


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## MusicMan (22 Oct 2017)

I only paid £400 for my Arboga (a bit bigger). It's not crazy money for what you get, but with patience you could get one cheaper.


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## skipdiver (22 Oct 2017)

I'd be quite happy to pay £400 or more for what i require. I will keep an eye out on all the usual sites as i am in no hurry. I have enough parts machined up to keep me going for a while, so thought i would start looking at possibilities well ahead of time, given that my metal working skills and knowledge are negligible.


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## SteveF (22 Oct 2017)

I just paid 430 for my arboga
but without a table
so add that and then a vice on top the price did climb up quite a bit
mine is imperial but with the addition of some linear scales (more money) this would give you metric as well
so while you are keeping an eye out, be mindful if you want\have to add extras

Steve


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## J-G (22 Oct 2017)

skipdiver":1b5x1259 said:


> I don't mind working in either metric or imperial, but am at a bit of a loss as to why these machines come in both variants. Is it the parts you fit to them, ie chucks that differ? Is it the register marks and displays that are in inches, instead of cm's?
> 
> Ideally, i wouldn't want to mix wood and metal on the same machine but space is the issue i have. I think if i rig up a good extraction system, i can minimise cross contamination.


As MucicMan has said, it's the lead-screws which determine which measuring system is used and that means that the dials have to match. The tool-holding and work-holding parts can be whatever you want/have. Chucks are held in Morse tapers with draw-bars and both Imperial (3/8" BSW) and Metric (M10) draw-bars are supplied with both variants.

I have the WM 16 and use it for all sorts of materials - Steel, Brass, Alum, Delrin, Tufnol, Perspex, all manner of exotic and home grown hardwoods plus plywood and chipboard. There is nothing extra to take account of when switching between wood and steel than there is between Brass and Alum - yes you need to be aware of potential cross contamination of swarf and sawdust if you are disposing of it considerately but that's just a part of normal workshop etiquette.

The 12 has a top speed of 2000 and the others 2250. Not the speed of a router, planner/thicknesser, spindle molder, Dremmel or Kress, but if you work that much on wood the chances are that you already have that sort of equipment anyway. I used to have a Proxxon MF 70 - two in fact - both of which had a motor burn out and Proxxon didn't bother to answer my requests for replacement (motor that is). That ran at 5-20000 and when I bought the WM 16 it was one of my 'issues' but in reality I haven't been compromised - I've made more use of my router table, but even that only runs at 3000.

I'm not convinced that the 500W of the WM 12 would handle a 50mm Forstner bit in (say) Oak but it probably would in chipboard. I only have up to 40mm so can't do a test in my 750W WM 16. I know that my 370W Pillar Drill doesn't perform well with my 40mm in softwood or chipboard! 

If your budget can stretch the extra £150 to the WM 14 you gain a number of benefits, 12½% more speed, 20% more power, 32% more travel, 25% longer table, 20mm more 'throat' - and the metric version is in stock. 

It would be worth giving Warco a call to determine how long the metric WM 12 is likely to be out of stock, it may well be that they have a shipment due or recently arrived and in their pre-sale inspection dept. (that happened when I bought mine, I had to wait about 10 days).

I must disagree with Rorschach (cross-post). Metric Dials on Imperial Lead-screws would be the worst of all worlds. Assume 10 tpi, one turn would be 2.54mm so the dial would have to have a mark every 14.173228° (for .01mm) with a space of 5.66929° !!! - - I know we now have CNC options and it could easily be done but why? If you have Glass Scale DRO that's a different kettle of fish and both systems can co-exist.


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## skipdiver (22 Oct 2017)

Thanks for the first hand info J-G. It's always nice to hear from someone who has the tool you are considering. I'll probably never drill a 50mm hole in oak. I do have a 50mm forstner bit, but it's not been used in anger yet. I think the 12 would be adequate for my needs but i'll talk to Warco and see what they have to say before i make any decisions.


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## MusicMan (23 Oct 2017)

Imperial Arboga? That's unusual, as they were made in Sweden and Germany. Still as you say, with linear scales you'd never look at the dial.


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## SteveF (23 Oct 2017)

MusicMan":39gnb2ot said:


> Imperial Arboga? That's unusual, as they were made in Sweden and Germany. Still as you say, with linear scales you'd never look at the dial.


sorry should have stated the drill is metric
the table is imperial

Steve


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