Giles' misc. Work bench.

[simond]

Simon,
This puffer winch might interest you, as it's making offers a Third Option, namely making things "the proper way", but with cheap and speedily-worked PLA:
View attachment 177497

To give a sense of just how small it is, here are components in progress on fingernail - probably a small one, as its owner is a Korean woman - maybe 10mm diameter max:View attachment 177498

These components began as PLA filament, here being laid down with a 3D Pen:View attachment 177499
While still molten, the PLA was squished into a flat sheet between two rulers, then worked like Plastikard.
The fine rods are made by heating and stretching 1.75mm stock. Fatter rods are cast by squirting the 3D Pen into a tube, parts are bent using heat, carved using heat and burrs, and turned using either a mini-drill or a £30 Chinese lathe.

A benefit of this approach is that most regrets, mistakes or omissions waste far less material than they would on a 3D printed Monolith Though the Monolith will always win for Multiples

(I know none of this belongs on Giles's Workbench - I'm just sympathetic to Simon's dilemma.)

For more 3D Pen mastery - including sculptures as well as the complete ship and a BMW motorcycle, look up Hoo's Mini World

https://www.youtube.com/@hoosminiworld

David

Well, I watched most of it, he’s a clever boy (or she’s a clever girl!) there’s some real craftsmanship there, but I’m left wondering why one would start with a 3D pen if a sheet of plasticard would be both quicker and more appropriate for the job in hand.

lovely job though!

thx
Simon

 

[JimG]

Jim,

thanks for sharing your development of Giles idea.

two questions, if I may;

what resin?

which slicer?

and I guess by extension, which printer?

thx
Simon

Simon,

The printer is a Phrozen Sonic Mini 4K with a 35 micron pixel size.
The slicer is the free Chitubox 1.8.
The resin is Phrozen Aqua 4K. This resin is "softish" and a harder resin would probably be better for step chucks. But it gives excellent definition. I got the impression that this resin was brought out to go with the higher resolution mono LCD screens.

Jim.

 

[Giles]

As well as wheels, I have outside cranks to consider (boring). The answer to consistency is of course the same as for wheels, as just as easy.

https://flic.kr/p/2oaynki

 

[simond]

There is something a little surreal about printing a chuck to hold something distinctly irregular / non-circular.

It really does offer some extraordinary possibilities.

 

[David Halfpenny]

Well, I watched most of it, he’s a clever boy (or she’s a clever girl!) there’s some real craftsmanship there, but I’m left wondering why one would start with a 3D pen if a sheet of plasticard would be both quicker and more appropriate for the job in hand.

lovely job though!

thx
Simon

As most of what she does is 'sculpture', I doubt she has a stock of the flat stuff, Simon

But as I do, I'd use a mixture of sheet, extrusion and filament.​

There's some scope for using a 3D Pen for small low-pressure injection mouldings.​

(I've known people use a glue-gun like that, using appropriate sticks of course.)​

​

BUT I'm wary of routinely using heat on Styrene-based plastics: carcinogenic vapours.

​

She's done a sub-titled detailed review of her plastic-modelling toolkit - describing herself as 'Greedy for Tools' (kindred spirit).

This is well worth a watch, even if one never intends to hold a 3D Pen:​

​

​

The other product she uses a lot is UV-cure Resin - including this ingenious Lost Wax cored lamp-glass:

​

And this video also shows good use of a £30 lathe - which could stretch a lot of people's modelling capabilities ​

​

 

[Renovater]

Thanks for the info, that's a handy little lathe for lots of small different things. I've just bought one on the ebay (37 euros !) after reading your post to try it out, the motor runs on dc, so it's easy to fit a controller, wait and see.

Cheers Colin.

 

[Boyblunder]

I like the idea of using a modified cheap electric toothbrush for sanding small areas. Has anyone else tried it?

 

[simond]

Yes, but not with any rigor. I will report more when I have something important or tedious to sand…

 

[Giles]

And finally the collet for boring the crank pin hole in outside cranks

https://flic.kr/p/2ob92G9

 

[michael mott]

I have also been struggling with how to sensibly and affordably hold the wheels for boring centre's true. Finally the penny dropped, and I printed my own collets

Giles this is brilliant! the first one and now these newer collets. The possibilities now are endless for the wierd and odd shapes that are difficult to hold but need a hole bored or a spot turned down.

Michael

 

[Giles]

Bless you Michael - very kind!

On the subject of quartering, there is a very simple solution for accurate quartering of outside cranks in this day and age of CNC, laser and printing, and this is mine. I have lasered these plates in 2mm MDF for my own convenience, but they could just as easily be printed.

The principle is that cranks are fitted to the wheel sets on one side, and then those cranks on both wheelsets are inserted into one of the plates. The cranks on the other side are then fitted to both axles and aligned using the second plate on a flat surface, and left to cure.

https://flic.kr/p/2objaTW

 

[Giles]

In a revisit to the pony truck situation, I decided that my loco will be radio controlled, and therefore by using one of my small gearmotors I can fit the propet full pony truck, rather than a radial truck (due to clash with a larger gearbox).

I decided to use a ball joint to give me decent articulation, and printed a truck with the appropriate A Frame accordingly. The ball socket is slotted at the front to allow it to expand and the ball to click in, and there are two tabs on the front with holes, should I need to wire-lock it closed.

The ball is the vulnerable bit, as the neck is only about 1.6mm dia., and would snap very easily. Therefore the stretcher has 0.6mm NS wire silver soldered as a pin, and the ball has a corresponding hole. The ball is epoxied onto the pin, to give it all the strength in shear it needs.

https://flic.kr/p/2obhU8X

https://flic.kr/p/2obkmhJ

 

[Giles]

I will print correct centres for the pony truck wheels

https://flic.kr/p/2obk7ev

 

[SimonT]

Giles,
what great idea. I am working on a 1:32 design of the Peckit Septimus and it has a similar problem to yours. I may imitate you sincerely!

Simon

 

[Osgood]

This is hardly modelling - better described as engineering in miniature.

 

[michael mott]

Model engineering in miniature, regardless it’s great to see what and how it can be done!
Michael

 

[Osgood]

I was thinking in the case of the spherical pony truck bearing, Giles - when you draw up the two components you have to decide 'up front' on the right clearance as difficult to machine afterwards, so if dead size the bearing may be too tight even with the split outer, if too much clearance bearing too sloppy.

So a leading question (about the trailing pony truck bearing) - did you get it right first time or did you re-print with altered clearance?

 

[Giles]

First time I left about 0.1mm overall clearance, but that was too tight, so the second time I left about 0.2 or so overall, and that worked out fine - but of course I think that will depend very much on printer, resin etc......

A bit of slop isn't a massive problem in this context, as long as it's not too much! What one really can't afford is for any binding to occur, as a derailment would inevitably occur - with one wheel stuck up in mid air! In practice, the pony truck is nicely free to move in all axis freely, which is what I was after.

I left tabs on the front of the split cross-'drilled' so I can wire it closed if I want. I can also tighten it a fraction if I want using a wire.....

 

[Osgood]

Thanks. I'm beginning to think there is no manual for this branch of modelling/engineering - instead very much a build-on-experience process.
Superb stuff.

 

[michael mott]

Thanks. I'm beginning to think there is no manual for this branch of modelling/engineering - instead very much a build-on-experience process.
Superb stuff.

I’m guessing you might have a another little book about this sort of modeling/engineering by a guy named Giles F……some time in the future though
Michael