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Post by Deleted on Mar 23, 2009 21:21:46 GMT
Hi all, I have just taken delivery of my first lathe - I have a drill press also but no milling machine - and have three basic questions.  1) I need to use a 7mm reamer in my first project (a Stuart 10V). I think that I can either buy one of the precise size, or get an adjustable tool, which I gather should cover a range of sizes. Should I stick with the precise size bit, or are the adjustable tools OK? 2) I am intrigued by threads on this site, and others, about using a slitting saw in the lathe to cut sheet metal (mostly aluminium would be my use). Is this really safe? If so, what thickness blades should be used, how many tpi and what width of blade? Or do these all depend on the type of metal and thickness of metal that is to be cut? Are there any "reference tables" anywhere to help with this? How is the sheet metal clamped/held (presumably to the tool post, cross-slide or saddle somehow)? -I would hate to get my hands and fingers anywhere near the saw blade  3) My lathe (Warco BV-20) does not have a vertical slide, although one is available (cost is around £165). Are these attachments worthwhile? Or if I feel I need milling capabilities, am I better saving extra money for longer to buy a dedicated milling machine (which I think could easily cost many hundreds of £s)? All comments gladly welcomed ;D- thanks, Alasdair |
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Post by alanstepney on Mar 24, 2009 7:25:24 GMT
Welcome to the forum.
1. An adjustable reamer produces a hole that has a slight taper unless you can run it right through, and/or from both sides.
It would be easier to use a 7mm one in this instance, expecially for a novice.
But, read about and learn to make D bits, which will save you from buying reamers of every size.
(Tracy Tools are worth contacting for reamers (and much more) as they are usually cheaper than most suppliers).
2.Safe?
Wear goggles and keep fingers away.
Like many activities in the home workshop, it is as safe as you make it.
A lot will depend upon what you are cutting, how thick, and how often.
If you need to cut a lot of material, it might be worth considering one of the bandsaws that are readily available.
With any saw, the rule is that you should have at least three teeth in the thickness of the work.
Speed is less important to us, unlike industry where they need to keep up productivity.
Start slow and gradually increase the speed. You will soon learn what is right for each situation, and, more importantly, your set up.
3.
A dedicated mill is better, but for many years, milling machines were rare in model engineers workshops and a lot of people still dont have one.
Whilst useful, it tends towards the luxury end of equipment.
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Post by drjohn on Mar 24, 2009 7:34:31 GMT
Hi Alasdair - welcome to the forum. To your first question, I would personally go for the fixed reamer, then you know exactly what size the hole is. To your second - gives me the heeby-jeebies thinking of cutting sheet metal like that - I use a wood saw with the teeth ground off and a hacksaw blade attached - works well for bigger sheets - my bandsaw only has a 4" throat.  And to your third - yes a vertical slide is extremely useful for all sorts of jobs - just wish I could get one to fit my Chinese lathe.  No doubt you will get more replies from much more learned enginners - I'm of the suck-it-and-see, self taught brigade ;D DJ |
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Post by dickdastardly40 on Mar 24, 2009 7:52:24 GMT
In addition to the good advice above, non-adjustable hand reamers are tapered for approx the first third of the length of the flutes. Not a problem if you are reaming a through hole but not so good for a blind one. If you can back up the reamer with a centre in the tailstock to keep it straight, pack the flutes with cutting compound (trefolex or similar) have the pilot hole 1/64" (0.4mm) undersize. Don't force the reamer, use firm pressure but allow it to cut.
I have never tried to cut sheet metal with a slitting saw.
A vertical slide is a nice addition to a lathe even if you have a milling machine, I still use mine on occasion. However figure in the cost of a vice to suit (possibly the Warco one comes with), a collet chuck for milling cutters for your lathe and possibly a small angle plate to maximise set ups. You will find that often the base price of anything needs ++ added for tooling. This is especially true with milling machines.
Welcome to the site and the hobby, good luck with your project.
Al
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russell
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Post by russell on Mar 24, 2009 9:15:27 GMT
Be warned. Many drawings of models specify a reamed hole of a certain size and a silver steel or other precision ground axle is expected to run in it. It wont! You will need a thou or two (0.025 - 0.05 mm) clearance. An adjustable reamer can achieve this or you can use a fixed reamer and reduce the axle a bit by spinning it in the lathe against a bit of fine oiled emery cloth. (watch your fingers!)
Russell.
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Post by Deleted on Mar 24, 2009 9:53:50 GMT
Many thanks Alan, Dr J, DD and Russell for the replies, and thx also for the welcome. ;D I will go for the fixed reamer. I will do further research into using a slitting saw in the lathe, as I must admit I am a little uneasy about the safety angle.  Will also consider the vertical slide, as I think I can find all sorts of uses for it - but take the point absolutely that additional tooling will be required which could easily double the original cost - may look on Ebay for something, but am a little reluctant as I prefer to see "in the flesh" and feel what I am buying rather than going from a picture/photo. Regards, A |
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steam4ian
Elder Statesman
One good turn deserves another
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Post by steam4ian on Mar 24, 2009 10:40:22 GMT
Dr John Thanks for your idea about the sheet metal saw. It is ages since I saw one in the flesh. You have inspired me to make one, may even buy a cheap wood saw to do the job. I will soar to new heights  Regards, Ian |
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Post by drjohn on Mar 24, 2009 14:35:52 GMT
Be careful Ian - soaring when you're upside down in Oz can be dangerous! ;D especially with a saw in yor hand!
DJ
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Post by engineernut on Mar 24, 2009 17:36:53 GMT
Hi all, I have just taken delivery of my first lathe - I have a drill press also but no milling machine - and have three basic questions. 1) I need to use a 7mm reamer in my first project (a Stuart 10V). I think that I can either buy one of the precise size, or get an adjustable tool, which I gather should cover a range of sizes. Should I stick with the precise size bit, or are the adjustable tools OK? 2) I am intrigued by threads on this site, and others, about using a slitting saw in the lathe to cut sheet metal (mostly aluminium would be my use). Is this really safe? If so, what thickness blades should be used, how many tpi and what width of blade? Or do these all depend on the type of metal and thickness of metal that is to be cut? Are there any "reference tables" anywhere to help with this? How is the sheet metal clamped/held (presumably to the tool post, cross-slide or saddle somehow)? -I would hate to get my hands and fingers anywhere near the saw blade 3) My lathe (Warco BV-20) does not have a vertical slide, although one is available (cost is around £165). Are these attachments worthwhile? Or if I feel I need milling capabilities, am I better saving extra money for longer to buy a dedicated milling machine (which I think could easily cost many hundreds of £s)? All comments gladly welcomed ;D- thanks, Alasdair Personally I would go for a separate milling machine. I have found that if one buys a machine/attachment thinking it will be big enough it always (well for me it does) end up where a job comes along where you need that little bit extra room. For the cost of buying a vertical slide plus all the other bits you could probably buy a mill. Just as an afterthought do Stuarts now sell there plans & castings in metric as they always used to be only Imperial? Well they were last year when I purchased two separate engines from them? |
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Post by havoc on Mar 24, 2009 20:23:27 GMT
Euh? I don't know how you use your reamers or what type of reamers of what type of silver steel, but for me and a lot of others this works perfectly. The reamers I have/buy are rated H7 (haven't seen any other except for the adjustable type). Together with the usual ground silver steel this works very well.
The adjustable type can be useful, but in order to use it you should first make a gauge to set your reamer.
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jackrae
Elder Statesman
Posts: 1,333
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Post by jackrae on Mar 24, 2009 21:03:59 GMT
If you want to keep a full set of digits, don't even think about using a mandrel mounted slitting saw to cut sheet metal on a lathe. These tools are for SLITTING slots in rigidly mounted metal securely clamped to some form of movable bed.
If you want a machine and cannot afford a bandsaw then get hold of a guillotine
jack
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wayne
Seasoned Member
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Post by wayne on Mar 24, 2009 21:46:53 GMT
The ideal chose for sawing material would be a stand alone machine ie band saw, guillotine, shears ect I have one a Warco combination roll guillotine bender (see Warco, Chester, Rgd Tools all sell them just in different colours), a good machine to use but it is only rated at cutting 0.6mm thick material, my seven series Myford table saw attachment with bridge can easily cope with 6mm thick + material. So I use both This item is long out of production an the last one on fleebay fetched over £300.00??? if my memory serves me correctly. All is not lost though Hemmingway kits do a saw table and arbour for small lathes in a kit form, the making of it was illustrated a few issues ago in MEW (Model engineers workshop) . It’s basically a same as the Myford item, it is used for cutting thin material which can be clamped to the table, the cut is feed in from the cross slide. It is only capable of handling smaller sheets. See the following links www.hemingwaykits.com/acatalog/Saw_Table_Attachment.htmlOr alternativly www.hemingwaykits.com/acatalog/Sawing___Filing_Attachment.htmlBoth these peaces of kit are really from the days when the lathe had to do all the jobs the model engineer required, however if you do build any tools form kits or drawing you are learnig houw thjings are don and how to use your machines Incidentally both were originally designed by Potts Regards Wayne |
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ace
Statesman
Posts: 528
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Post by ace on Mar 24, 2009 21:53:21 GMT
Welcome to the forum alasdairm.
As I have done why not visit one of your local engineering shows and look around some of the second hand stalls, I have picked up many a good bargain on reamers, taps and dies etc. Also this is how I have managed to buy second hand milling equipment to fix on to my Myford lathe this way I could see what I was buying. I have done well using the old stuff and then bought newer as and when I have the cash and on a need to have basis.
Good luck
ace
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Post by Deleted on Mar 24, 2009 22:22:04 GMT
Just as an afterthought do Stuarts now sell there plans & castings in metric as they always used to be only Imperial? Well they were last year when I purchased two separate engines from them? Hi Engineernut - although the Stuart 10V plans/instructions with the casting kit are imperial (and very brief indeed!) the booklet that I purchased from them at the same time called "Building a Vertical Steam Engine" by Andrew Smith, revised by Pengwern, includes both metric and imperial.  As I am so new at this game, I really do need the book, as I cannot imagine me having any joy at all just working from the plans/instructions with the casting set itself! ;D Regards, A |
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longor
Involved Member
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Post by longor on Mar 25, 2009 10:17:53 GMT
Hi Alistairm, can I add my twopenneth. The best way to cut sheet metal in small quantaties ,if to thick for snips, is a power jigsaw with metal blade, a bit of practice with speed and feed and it will cut almost like a nibbler, grind back of blade to cut small curves. I've just been cutting 2mm MS. Use parrrafin on alluminium. Milling etc. on lathe:- dont buy anything until youve had the lathe for some time,milling & boring can be done by bolting to topslide using packing, angle plate, bits of wood even,for one off jobs. Make a tapped plate for topslide as was suggested to me on this site recently, good idea.
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Post by engineernut on Mar 25, 2009 17:45:15 GMT
Just as an afterthought do Stuarts now sell there plans & castings in metric as they always used to be only Imperial? Well they were last year when I purchased two separate engines from them? Hi Engineernut - although the Stuart 10V plans/instructions with the casting kit are imperial (and very brief indeed!) the booklet that I purchased from them at the same time called "Building a Vertical Steam Engine" by Andrew Smith, revised by Pengwern, includes both metric and imperial. As I am so new at this game, I really do need the book, as I cannot imagine me having any joy at all just working from the plans/instructions with the casting set itself! ;D Regards, A I think once you have built an engine you will find reading the plans becomes easier. ;D I have built quite a few engines over the years and although the majority of the time there is not a lot in it I find Stuarts are probably the easiest, especially if used in conjunction with their books on building. I think you will also find on quite a few plans that there are slight mistakes. If I am making a mating part I always check the other bits that go with it to confirm all the sizes are compatible. Some plans I have used have, initially, been a right pain but there is certainly a feeling of pleasure when you suss them out and everything works. After a 10V one of the first engines I made was the Stuart Beam (still have that) and I am just finishing another Beam from a different supplier. Good luck in your first project. |
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Post by engineernut on Mar 25, 2009 17:57:23 GMT
As a quick thought when you come to turn the flywheel, rather than go into great detail now as there are threads on here dealing with this, but just to confirm when you drill the hole for the axle you finish the final hole size by boring it. You will get a perfectly true running flyheel then.
Cannot remember offhand but say axle is 1/4" dia then drill hole in flywheel say 3/16" and bore it out the last 1/16".
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jasonb
Elder Statesman
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Post by jasonb on Mar 25, 2009 19:11:12 GMT
Be careful if using the metric sizes from the book as the bar and rod supplied with the kit is likely to be imperial. eg a 9/32nd rod won't fit a 7mm reamed hole, Maybe this was Russells problem Jason |
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russell
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Post by russell on Mar 26, 2009 9:05:31 GMT
Jason,
Of course a 9/32 rod won't fit a 7 mm hole. Equally a 7 mm rod will fit a 7 mm hole but it will be a push fit. It won't spin. For a normal running fit (according to Tubal Cain's M. E. Handbook) you require 1.0 to 1.5 thou clearance per inch diameter. A slightly bigger proportional clearance is required for smaller diameters, a 1/16 shaft won't run very easily with less than 1/10 thou clearance.
Havoc,
My reamers cut to size (the worn ones slightly under). I haven't come across the H7 rating. Can you explain what this is? Is it slightly oversize?
Regards,
Russell.
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Post by engineernut on Mar 26, 2009 18:56:28 GMT
If a rod is going through a piece of metal for say a flywheel then the hole should be bored. ;D If the rod is going through a piece of metal for another reason and boring is not practical or needed then a reamer is used the same size as the "say" axle. ;D If then tight a rub over with scotch bright does the trick.  We are only talking of microscopic amounts here and if one tries to take that extra 1/2thou off with a cutter then sods law it will be more resulting in slop.   These extra little bits get removed in running in of the engine. That’s why it is called that. |
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