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[Bryan Young]

This is a subject that I have been musing over for ages. Engineers I have asked about them just seem to talk like the people who write computer instructions. Right over my head....followed by a pitying look. Is the making and use of them a sort of Masonic thing, or can anyone join? The replies I have had range from "Use an old hacksaw blade" to "Be careful with the alignment". None of which are of much use to a beginner.
I have need of such a tool now to make a multitude of identical small "bits". All in either aluminium or brass.
Please, could any replies be written as from "square one" on the (correct) assumption that I know nothing. Ta. Bryan Young.

[bogstandard]

Bryan,

I would attempt to have a go, but you would need to tell me what you want to make, plus also if you have any equipment to make any fixtures and fittings, or is it purely hand tools. Or maybe you want a fixture making?

Either PM or email (preferably) if you want to keep it a secret.


Bogs

[warspite]

my first impression where the term form is used is casting, to me, the form is the shape to be cast, split in two.

[andrewh]

Its what hare leaves its leverets in, too

Bryan, I'm with Bogs - you need to give a clue to the masssed ranks so they can dive in with appropriate suggestions as well as mine

I can reveal one thing, though.  You can certainly join in the Fun of Forming (as long as you can roll up a trouser leg  and hop widdershins

In the whole of engineering there is little that can't be done in the home workshop - it just takes longer and sometimes needs more care

Having reread your post I guess you are turning things?  Lathe, vertical drill, power drill , hand drill?  What have you got as tools and raw material.
If you are turning then a form tool will depend on the shape, length, etc of the part you need.  very hard steels can be good  - industrial hacksaw blades, old files  - anthing that has a long enough edge to be ground to the shape (actually half the shape) you require

But I'm guessing
andrew

[Bryan Young]

Aha! A possible set of serious answers to a serious query!.
1..I have a small lathe (which I'm reasonably good at using).
2..I have a vertical mill/drill with a compound table (that I am also reasonably adept with).
3..I tend not to use steel, preferring brass and aluminium for model work.
You ask what I am making. Does that matter? But for arguments sake, let us suppose I'm making stanchions. But it's the principle of the thing I want! I realise that the "form tool" would have to be a negative image of the final offering....but how would I make it? How would I put on the cutting edge? How would I hold it in a normal lathe tool-holder? How would I turn one part before the final part snaps off? All silly questioins I know, and probably easy for a trained engineer. But I was a "deckie" and like ocean navigation is a black art to an engineer, so making and using a form tool is to a deckie. So, principles and guidance ic what is most eagerly required. Ta for the interest. Now show your teaching skills! Bryan Y.

[andrewh]

Bryan,

Thanks for the reply - Bogs will reveal the ENTIRE correct way to do this kind of thing, no doubt, shortly.

Yes it matters - not what you are making but the ratio of diameter to length - cos this is what dictates how you do the thing and what support it needs!
If it was short and stocky - like say a bollard you could cut it all in one form  - you might rough turn to shape then use the form tool to make them all identical. 

Long and thin like a stanchion - especially in relatively soft metal - needs support! and you can't cheerfully plunge in with a form tool say 60mm wide.

So sensible answers follow.
Snippets in advance as I prepare to head for bed:
Form tool - needs as you say to be the reverse form of some or all of the part.
Geometry says it can't have the positive rake you would like at all points - many form tools are just ground perfectly square, and the top (sharp) face fed in on the work centreline
Yes, it will rub and also cut
I have been known to make form tools out of wood - carve/file the relevant female shape and line the shape with glued-on sliicone carbide paper then apply the abrasive form tool to the work and be patient (and keep it cool)

andrew

[tigertiger]

As an outsider looking in to this topic.

How would you provide support for someghing like brass rod, if you making something like stantions?

[bogstandard]

You couldn't possibly hope to describe what you require in one posting, maybe not even ten would be enough, as there are so many variables to be considered, lathe size (a small lathe can only form small pieces because of the cutting forces involved). Materials, brass doesn't require top and front rake (you should be familiar with that term if you can use a lathe) whereas with ali and steel, you might just get away (if you are careful) with just a little front rake on the tool. The materials for making the cutters also comes into it, if you are going to be using pre hardened tooling (hacksaw blade or HSS tooling) the profile will need to be ground to form by hand, rather than cut on a machine. If you know what gauge plate is (a material that is very easily hardened by heating and quenching in water) then the form can be machine cut, then the tooling is hardened and dressed sharp afterwards.

So I can show and tell you how to make a form tool, but it would need to be for a specific material, using a specific tooling metal (hard, or soft then hardened) otherwise I will be here forever trying to describe everything that is required for all materials. If you can also give a specific shape that is required, as every form tool is made for each individual type of job. There is no be all and end all, again it needs to be specific for the job in hand.

If you can follow the above and agree to doing just one type, then I am sure, that after I have finished, you will be able to do it blindfold.

I would suggest starting off easy with a pre hardened tool and brass as the material. Once you can achieve results using that method, you can then progress onto more difficult shapes and materials.

One thing you mustn't be fooled by are fittings you can buy in the shops, such as stanchions. They will not be cut using a form tool, but a single point CNC lathe or machining centre, and as such they are cut from the end away from the chuck and cut towards the chuck, so the rigidity on the material keeps it all stable. When you cut with a form tool,, say stanchions, you would use the form tool to make the balls, and a normal cutting tool to dress between each ball, again working towards the chuck so the material has some latent rigidity until the final parting off, or making up a blank using normal tooling and a form tool to cut the spheres.

Here is a very small forming job I did a few weeks back, to show you that there is more to it than you think.

I needed to make a load of acorn nuts for an engine I was restoring, so I made up the blank closed face hex nuts.



Then a tool was profiled to cut from the end rather than plunged into the side. Otherwise the cutting forces would have broken the very small 8BA mounting screw.



A mandrel was made to hold the blanks whilst being profiled.



The profile tool was fed onto the end of the work until the saddle came up to a fixed stop.



It took only minutes to profile a load of them, all exactly the same.





Bogs

[Bryan Young]

Amazing! I've learned more in the last 10 minutes than I believed possible.
However, I will beg your forgivnesses (such a word when referring to 2 people or more?) if I take a couple of days to mull over what has been said. Most of it I understand and can apply but there are a couple of things that leave me hanging....I'll get back. Thanks for the interest and I'm sure I'm not the only forum reader who is grateful to you both. Cheers. Bryan.

[bogstandard]

That is what we are here for, there are no trade secrets or black magic, just techniques that have been in use for centuries. A lot of them are dying arts, thru lack of use due to modern technology. I don't profess to know all of it, but I will always try to help if I can.

It just needs the techniques explaining in an easy to understand form.

It is the same with myself, I get lost when trying to understand electrickonical widgets, wiggly amps and electric string. If it is explained in laymans terms, then no problems.

Bogs

[Bryan Young]

I'm sorry about this....really, I am. Although genuinely interested in the idea, manufacture and use of a "form tool" and appreciate the replies given (thanks a lot)....my main reason for asking is because I'm now saddled with the manufacture of the ships wheel.
This thing is at least 4' in dameter and possibly 5'.
I have access to, and have perused William Mowls description of how he made his for either the "Warrior" or "Great Britain". But on reading this I wondered if he had actually made it himself or (like many other tasks on the 2 ships) sort of "farmed it out" to another person.
I don't have a 4 jaw chuck , so turning up from the round is my only option (unless there is a better idea). I would really like to make a decent job of this as it's so prominent....including the small ancilliary wheel.
Hope I haven't upset you too much. Bryan.

[bogstandard]

Methinks 4' to 5' is a little large for your lathe, are you sure it isn't 4" to 5".

Now are you talking about manufacture from wood, or metal?

Basically to get it really spot on you would require a rotary table on the mill to ensure perfect register.

You would turn the outer rim and the separate hub on the lathe. Then mount the parts onto the rotary table or indexer to accurately drill the correct qty of holes around the rim and into the hub. Then you would turn the spindles up and assemble them all together like a spoked wheel.

The spindles should really have the profiling done in say three or four stages along their length, allowing the setting up of a rear support to take the bending force when the profile tool is pushed against the material. So basically, you would cut all the spindles with the first profile tool, then swap tools, set up the rear support, then cut the next section along the spindle, and so on until the whole length of each spindle has the correct profile along their whole length.

Actually, it doesn't take all that long, it is making the tooling that takes the time. Maybe only five or six hours if you get the profile tools right first time.

You would repeat the above for the smaller wheel.

BTW, you don't need to have a four jaw to turn a disc out of square. You just need to have the bottle to do friction turning on your lathe.

Read the first page on here, where I go into detail how to do friction turning, turning plate material into discs for making flywheels.

http://madmodder.net/index.php?topic=871.0

Bogs

[bogstandard]

Now looking at the wheel a little more, it is in fact easier than I thought.

You would really only need two form tools, to shape square wood. The first form would be to shape the handles with the square left on the bottom, the second form tool would be to profile the middle spindles out of a single piece, leaving the square on the ends.

The spindles would need to be drilled right thru and the handles only half way and on assembly, round dowels would be fed thru the spindles from the outside to the hub, then the handles glued onto the projecting dowels. Small flats would be machined around the periphery of hub and rim at the same position as the drilled holes. This would allow the squared ends to sit nice and flush.

Hope you could understand that.

Bogs

[Bryan Young]

Now looking at the wheel a little more, it is in fact easier than I thought.

You would really only need two form tools, to shape square wood. The first form would be to shape the handles with the square left on the bottom, the second form tool would be to profile the middle spindles out of a single piece, leaving the square on the ends.

The spindles would need to be drilled right thru and the handles only half way and on assembly, round dowels would be fed thru the spindles from the outside to the hub, then the handles glued onto the projecting dowels. Small flats would be machined around the periphery of hub and rim at the same position as the drilled holes. This would allow the squared ends to sit nice and flush.

Hope you could understand that.
I understand the language, but have got a bit lost with procedures!. I shall muse again! Thanks for the interest.
BTW....perhaps if you could make these things commercially you would have a steady source of income!
Also....the 4' or 5' was, as I'm sure you posted in jest, the "real size", at my scale it will be 2.5" in the round. Bryan.

Bogs

[derekwarner]

I once knew a wheel builder...........[he is in wood workers heaven now]..... not only did he produce ships wheels ....but thousands of other wooden items......BUT also built his own machinary...lathe, bandsaw, thicknesser, spiral fluting machine.......& many more

If I could be 1/10 as capable as him I would be very proud  ....on ya Dad   ....no rotary tables...bur every set of components were jig produced... including the final assembly & gluing

In the first .jpg...you can see that the handle & spindle is actually one piece & these are secured into the central hub....& also to the outer rim

PS......I think BY maybe talking about a ships wheel that is 4' to 5' in daimeter....the standard size wheels that my Dad built as shown here were 36" diameter ....no not the wheel rim....but the pin to pin diameter.......... Derek

[bogstandard]

Bryan,

Yes, it was said in jest, got to get a bit of humour in sometimes.

Just a note, my workshop at one time catered for any materials, but unfortunately, a while back, after over 40 years, I had to give up model boat making (the front garden wall is now my walking limit), so all tooling to do with the brown stuff was removed, and now basically only works in man made materials (except for the odd model engine wooden base). Now if you wanted one making out of brass or aluminium, that is another proposition.

I have done a rough sketch to explain the method of assembly.



I hope this explains it better than my text did.

Derek,

Lovely workmanship, but where are the other bits of the ships that bolted onto them? Unless you are sailing your house around Goolongong.

But it does explain what I was on about. For ease of manufacture, the wheel rim would be made as a ring, and the spindles would be simulated to be made as one piece, hence the flats and recesses machined out of the rim. Unless you wanted to spend many hours making jigs and fixtures to make it like the original would have been made.

Bogs

[Proteus]

the wheel ring could be laminated then turned with the last laminate held with double sided tape then removed to fit the spokes then glued on permanently


Proteus

[derekwarner]

John...according to Max [dear Dad] the premise of the laminated construction in ships wooden wheels was to optimise strength........afterall the larger versions onboard larger vessels...eg., HMS Victory & irrespective if the rope reduction ratio...the actual wheel structure was placed under great mechanical stress

I understand stagered or segmented wheel construction had been used for centuries...& prior to HMS Victory

So we see the shear line in the grain of a one piece rim construction as opposed to the segmented wheel construction ...not really all that different as to why we use steel forgings ...for boundry grain strength  .........Derek

[Colin Bishop]

This sort of thing is way beyond my abilities but in view of the comments about wheels having to take physical stress the two pics below may be of interest. They are of HMS Warrior and the sloop HMS Gannet.

Colin

[derekwarner]

Thanks Colin......in IMG4090 we can see that eight seaman could man the wheel/s if needed.......there was no power steering...just the number of turns of rope reduction which went below to another drum with the same number of turns...then hence aft to the actual rudder chains...this concept is the same as multiple reeving in overhead crane applications

In the same .jpg you can see the brass cap on each wheel handle or pin @ the 12.00 o'clock position which represents that the wheel is @ dead ahead position

In the .jpg of Gannet we can see two ropes coming down from the bulkhead to hold the wheel pins on a set course......in an HM Man of War vessel no such contrivances would have been permitted........... - Derek

[bogstandard]

Very nice indeed, and super interesting, maybe an article on a dedicated post would be good, but wandering slightly from the question on this post.

I am trying to show the easiest way to produce a good facsimile of a scale wheel using machine tools to assist in the making.

Surely there are other people who have done this sort of thing, who can add to this post and get Bryan out of his self imposed predicament (been there and got the t-shirt).

I can only show how I think it should be done, others who have done the same thing might have an easier way to do it.


Bogs

[DickyD]

Is this any help.

http://www.modelboatmayhem.co.uk/forum/index.php?topic=13720.msg158824#msg158824

[Proteus]

this is prob the easyest way to do it a temp mod of your lath


http://www.youtube.com/watch?v=omQ4m0vUDLQ&feature=related

Proteus

[derekwarner]

Yes Proteus....this is exactly how Max constructed his mass produced ranges of components ...I loosley used the term 'by jig construction'.....in this case clearly I could have used the term 'by manuel copy attachment' .....Derek

[Bryan Young]

Methinks 4' to 5' is a little large for your lathe, are you sure it isn't 4" to 5".

Now are you talking about manufacture from wood, or metal?

Basically to get it really spot on you would require a rotary table on the mill to ensure perfect register.

You would turn the outer rim and the separate hub on the lathe. Then mount the parts onto the rotary table or indexer to accurately drill the correct qty of holes around the rim and into the hub. Then you would turn the spindles up and assemble them all together like a spoked wheel.

The spindles should really have the profiling done in say three or four stages along their length, allowing the setting up of a rear support to take the bending force when the profile tool is pushed against the material. So basically, you would cut all the spindles with the first profile tool, then swap tools, set up the rear support, then cut the next section along the spindle, and so on until the whole length of each spindle has the correct profile along their whole length.

Actually, it doesn't take all that long, it is making the tooling that takes the time. Maybe only five or six hours if you get the profile tools right first time.

You would repeat the above for the smaller wheel.

BTW, you don't need to have a four jaw to turn a disc out of square. You just need to have the bottle to do friction turning on your lathe.

Read the first page on here, where I go into detail how to do friction turning, turning plate material into discs for making flywheels.

http://madmodder.net/index.php?topic=871.0

Bogs

I'm now on my third reading and beginning to realise that I am mentally deficient. I knew that this wasn't going to be easy, but I cannot give up just because I can't understand the instructions!
"Nemesis" dropped a book off for me ...a "tome" rather than a book. I think it was published in 1750 or thereabouts. Now I have to buy a "new" lexicon to translate it all. Ah,well. Such is model making I suppose. BY.