|William Ayerst||28/11/2020 20:29:51|
80 forum posts
Andy, beautiful work! Right now, I'm thinking of moving home, so the double-benefit of a milling slide is that has milling and drilling utility (albeit not as great as a dedicated machine for either) but also importantly fits in a shoe-box when I pack up my workshop, instead of a crate. It's definitely on my watch-list, though - If I do find a cheap pillar drill, I will get one.
Nicholas, I appreciate it's probably extremely rote but I'm working from first-principles in this case - I had no idea if I could do it!
Angle plates on the ML7
Am I going to be fine with a simple right-angled plate with some milled oval holes, or is something more like the four-sided RDG plate with the vee groove, etc. ? I assume the latter but I don't have an extended cross-slide and there are no drawings or comments to establish what might be compatible with what.
What to clamp with?
Should I expect to use the same studding for clamping work as I do for my t-nuts? The T-nut slots look to be spot on 3/8" (rather than clearance for 3/8", and the t-nuts and bolts seem to be 1/4" BSF - I can't find clamping 'kits' in either size. How much of a bad idea would it be to just use 5/16" BSF bolts? They appear to have the correct distance across flats to fit into the T-slots on the lathe, and appear to be substantial enough to also clamp work.
Vice and Slide
I've sorted out a vice and a slide, time will tell whether it is the correct combination. I did go for Myford - my logic is that if it turns out to be duff then I can stick it back on eBay and lose only the commission!
|John Olsen||28/11/2020 20:54:53|
|1126 forum posts|
If you need to you can make all the clamping parts you will need. They don't have to be as pretty as the bought ones to work, and even if you have a set you will often find that you need a custom length of stud for something. Threaded rod is fine for these. Plenty of fine work has been done with just the lathe and vertical slide. A better chuck for the milling cutters is good if you can manage it, for instance an ER series chuck that either screws onto the mandrel nose or has a drawbar through the mandrel. If money is tight you don't need the full set of colletts, only the ones needed for milling cutters that you actually have.
Don't overlook what you can do with hand tools if all else fails. Tubal Cain did a series on machining one of the Stuart engines entirely with hand tools some years back. He bored the cylinder with a brace and bit. That was a bit of a tour de force just to prove that it could be done, most of us would at least use whatever machines we have. But you can do the odd bit with the hacksaw and file if you have to.
|William Ayerst||28/11/2020 20:59:10|
80 forum posts
John, fair enough - maybe I'll just sit on my haunches and see how the vertical slide works for now, now that I have it, and pull out the studding as and when required.
Ian T (I think) mentioned about using a faceplate-mounted ER32 Collet chuck and I'm with you there - machining faceplates and whatnot is a whole 'nother thing to learn. I am hoping that the very modest milling and drilling required for the oscillating engine linked prevously will be fine using what I have (on the way) now. Speaking of which - I assume best to use the 3-jaw for milling and the jacobs chuck for drilling, in the headstock?
|83 forum posts|
With a little bit more expenditure you could get a finger collet to hold milling cutters in the headstock spindle (you would need to make a drawbar - e.g. a long bolt + collar), I guess a 6mm and/or a 10mm collet (<£10 each) could cover quite a range of milling cutters.
FWIW, In the limited amount of milling I have done on my lathe (not Myford) I find the cutters run more smoothly in a collet than in a chuck and it's easier to see what you're doing.
|Martin of Wick||28/11/2020 21:28:56|
|222 forum posts|
I have never come across a commercial clamping set suitable for a Myford. Usually Tee bolts and nuts are available from mytholmroyd, but phone to confirm dimensions before parting with your money.
Not generally considered good practice to use ordinary reversed bolts as Tee bolts due to to small head size exerting a high point load and risking damage to the slot - but needs must if there is no alternative, just be careful you are clamping something solid over the top to protect the slot. Sawing up your own Tee nuts is a good discipline as is fabricating some Tee bolts
Myford x-slide tee nuts are pretty small, so that could be your first milling job to test the new slide, traditionally tapped 5/16 F but M8 would do as well if you are standardising on that studding.
Don't recommend using the 3 jaw to hold a milling cuter, too easy for the cutter to be dragged out of the jaws unless it is quite small. If you can't manage an ER collet chuck, then I believe ARC or the like can provide No.2MT collets in say M10 and M6 (or whatever to suit the mills you have available). M10 studding and a nut and washer will do for the drawbar.
Andy got there first with the finger collets!!!
Edited By Martin of Wick on 28/11/2020 21:30:11
|Michael Gilligan||29/11/2020 10:19:02|
17075 forum posts
I don’t think anyone has mentioned it yet .. but I would highly recommend that you get a copy of ‘Milling in the Lathe’ by Edgar T. Westbury
Amazon link for identification purposes only: **LINK**
One of the most useful little books on the subject that I have ever seen
I bought mine new, in the early 1970s
|William Ayerst||29/11/2020 10:35:47|
80 forum posts
I have 'Milling in the Lathe' on its way, and have just recieved 'Building Simple Model Steam Engines' - thank you. I'm going to read through before applying tool to metal for the oscillating engine as I quite like the look of the horizontal one complete with boiler - but we're getting ahead of ourselves. Either way, I've definitely got my next project lined up!
No milling is required for the stationary oscillating steam engine (nor I gather, the Elizabeth horizontal engine), the vertical slide is just going to be for precision drilling - so I have a little time before I need to figure out the milling component.
It seems that RDG do a backplate, chuck and set of collets so maybe that's a shout? £140 all-in doesn't seem too bad? (have I gone made, or has just the price of this hobby become completely disconnected from reality...). I would much rather get a used, german oro british set - but may bbe more challenging.
Edited By William Ayerst on 29/11/2020 10:36:16
1328 forum posts
I can't advise you whether to get a collet chuck or not, as that's down to your preference and budget.
Also consider getting a ball bearing closing nut, rather than a plain one; it really does make a difference.
Edited By peak4 on 29/11/2020 12:45:43
|William Ayerst||29/11/2020 19:02:23|
80 forum posts
What about the the myford MT2 collets and collet retaining ring? Then it's only £20ish for the ring and I can buy just a 1/4" collet initially, but the upfront cost is relatively low (and I'm not sending all my monies to imperial China)
I'm reading Tubal Cain's "Building Simple Model Steam Engines" and I am heartened by his words (as was described earlier in this thread) about making do with fewer expensive tools. I like the look of his horizontal-boilered Elizabeth but I am struck by how small it is a 1/4" bore against the 1/2" of the 'Simple Oscillating Engine' (both have the same 5/16" stroke).
He notes that bit of brass tube with a port block soldered benefits from heating up quickly compared to the hunk of brass to it needs much less steam to heat it to stop it priming, but it really does look so much smaller.
It would be nice to build a boiler which he details (44 sq. inch capacity with a 3-1/2" x 1/2" solid fuel burner) too. Will 15lbs of steam pressure from this boiler be enough for the larger engine, eventually?
|Nicholas Wheeler 1||29/11/2020 20:00:30|
|457 forum posts|
The ER collets aren't fussy about size, so you can use them for work holding and for unusually sized tools. And a set of square and hexagonal collet blocks come in really handy for other jobs like making squares, cross holes, flats and hand finishing
|William Ayerst||29/11/2020 22:46:52|
80 forum posts
Collets and Endmills
Thanks Nicholas - I'm basically split down the middle - either a cheap-o banggood MT collet holder + collet set for about £30 all-in, or looking at the Myford sets as previously mentioned at £25 per collet.
Tracy Tools do a set of end mills with 5/8" shanks, but I cant find any 5/8" myford collets available online. What size of milling cutter should I be expecting to work in, with a vertical slide? I'm guessing fairly small!
Steam Engine Choice
After some more reading and seeing some of Tubalcain's more recent videos, he builds something very similar to the simple oscillating engine and it runs fine on 5psi so I'm assuming that I'll be OK for boilers.
Both the Elizabeth and Simple Oscillating Engine are single-acting, and the one he made in his video is double-acting. It seems a simple amendment (i.e. two holes in the cylinder and two pairs of inlet/exhaust instead of one). Should I be concerned at all with single vs double-acting at this point?
Is there much difference in the output of the tubalcain single-acting oscillator (1/4" bore) vs the simple oscillator (1/2" bore) ? The fact the simple one is in metric is killing me, none of my drills or tools are in metric!
Edited By William Ayerst on 29/11/2020 22:59:21
1328 forum posts
I doubt you will do, I believe they only made them up to ½"
|Jeff Dayman||30/11/2020 02:20:35|
|1990 forum posts|
Don't worry about metric William, just make a photocopy of the plans for the simple oscillator and mark it up with the mm dimensions converted to inches with a calculator - just divide mm by 25.4 to get decimal inches. Example - you might not have a 6 mm dia drill for a cylinder bore but you may have a 6.35 mm one (1/4" ) This is very close to the metric size. If you adjust the piston size to suit a 1/4" bore rather than 6 mm it will likely work fine.
If you have a smartphone it likely has a good calculator app already. There are many calculator apps online. You don't need a handheld calculator anymore.
A handy tool set for any shop is a full 128 piece set of twist drills with fractional, number, and letter drills included, from #60 to 1/2". You will find sizes very close to many nominal metric dimensions in these sets. The 128 pc sets don't cost much from China now, and some are very good quality drills.
Edited By Jeff Dayman on 30/11/2020 02:20:58
|not done it yet||30/11/2020 07:06:17|
|5428 forum posts|
I would def be looking somewhere else. The price quoted HERE for an ER32 set is £920!
Now, that is disconnected!
19603 forum posts
RDG (and others) always do that when out of stock, saves having to relist the entire item, been said many times before on the forum.
19603 forum posts
Not quite as simple, you need to close in both ends of the cylinder, not familiar with the exact engine but at 1/4" bore I suspect the piston is also the piston rod all being 1/4" diameter. You would need to use a smaller diameter rod and short 1/4" piston then fit a cylinder cover with suitable hole for the piston rod.
That Minnie traction engine in my Avitar was done on an Emco lath with Myford slide and cutters held in the 3-jaw so basic stuff works.
Rather than a simple metric to imperial calculation suggested by Jeff, on a basic wobbler I would say just multiply each metric dimension by 1.0583 which will give you imperial stock sizes as well as proportional lengths.
|not done it yet||30/11/2020 09:52:55|
|5428 forum posts|
I know that, but it doesn't change my post - if he wants it, possibly this side of Christmas, does it?
|William Ayerst||30/11/2020 10:43:01|
80 forum posts
OK, for the sake of simplicity then I'll go for the simple oscillator scaled to imperial. It appears that as long as I get the inlet and exhaust ports, the pivot, the piston/rod length and the crank throw lined up the rest is academic...
Thank you all!
|Henry Artist||30/11/2020 10:59:43|
120 forum posts
< SIGH >
The Tubal Cain of YouTube fame is a 'merican gentleman who I believe used to teach machining in a high school. The author of the books was T D Walshaw, an English engineer, academic, and prolific contributor to the Model Engineer magazine.
Only one engine in the book is double-acting (Hercules). The others are single-acting so only require the cylinder to be closed at one end. There are many "rites of passage" in the world of model engineering and one of them is making a Polly. Even I have made one -
These days most people use gel fuel for their toy steam engines. No bad odours like you get with Esbit tablets and more convenient than Meths. In UK you can get gel fuel from B&Q.
The engines and boilers in Stan Bray's book can all be made with a lathe no bigger than a Unimat 3 or Sieg C0. The final project in the book is a locomotive.
Most toy steam boilers operate in the 10 - 20psi range.
The engine suggested by David George is an excellent project but will work better as a pneumatic engine than one run on live steam because there is waaaaay too much material in the cylinder which results in priming.
Edited By Henry Artist on 30/11/2020 11:04:22
|William Ayerst||30/11/2020 11:39:09|
80 forum posts
Thank you for taking the time to respond. I'm a little confused that Tubal Cain is listed as the author of the book, and in your video - if the author of the books was T D Walshaw? Is it a branding thing? Certainly I was confused to hear about various local british firms from an ostensibly Illinois-based engineer!
I definitely want to build a steam boiler if I get the engine running - after all, the whole point of this is to get ready to build a locomotive! So maybe an Elizabeth really is a better choice after all as it's already in imperial, is horizontal rather than vertical, will work on steam, and has a boiler designed to work with it...
As written the plans suggest brass tube with a 1/4" internal diameter, but I can only find 6mm and 8mm internal diameters. Is it feasible to just use the 8mm I/D tube and increase the piston diameter? I assume, if the boiler can deliver up to 15psi and Tubal Cain's double-acting equivalent with a 1/2" bore was running at 5psi, it would be fine. An alternative would be to machine down some 20mm stock to have an integral port at the back end, and reduce the material down to fairly narrow elsewhere?
Edited By William Ayerst on 30/11/2020 11:43:46
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