Have You considered getting a 3D printer

Tony it's you who has lost the plot and possibly your temper if your actions are anything to go by.

A model isn't just a small scaled reproduction of a steam engine, the fact that steam is no longer used is because engineering is dynamic, the really clever people seek to innovate and find new ways to design and create things that we have not yet seen, then many years later others will make those very same things for pleasure. If you don't wish to embrace the changes that's fine, your not going to lose the skills you have or be thought any less of, but don't knock others for doing things that you can't or don't wish to do.

Now how about you reinstate your membership and continue offering help when it's asked for.

|Posted by Journeyman on 30/01/2021 13:38:35:

|What is a 'Model Engineer'? Depends upon context and definition, it could be:-

1. An engineer who makes scale representations of a prototype machine / mechanism / engine etc.
2. An engineer who is an example to follow or imitate.

-----------------------------------

or even:

3. An engineer who sets up poses of young ladies showing off scanty negligees.

Edited By Peter Greene on 30/01/2021 16:16:52

Tony... it isn't either or. These are both works in progress in my workshop:

Surely what matters here is to respect everyone's creativity and right to do what they wish in the workshop, regardless of how they chose to do so?

Neil

My Grandfather made Sunderland flying boats during WW2, he is is described as an aircraft carpenter on my father's birth certificate and made Sunderland flying boats. He made a good few patterns and jigs and was very proud that some had to be accurate to a thousand of an inch.

I reckon they could have slackened that tolerance a bit, but who am I to know, all he stuff I designed sits on the floor and the Sunderland has an excellent reputation.

Not to mention that great piece of flying furniture, the Mosquito.

I helped to build 2 printers in 2017 with duel print heads. It was our (3 in the team) version of the BCN3d Printer. The upgrades were better rails, Stronger frame, an enclosure, Filament on the outside of the box with moisture bags. The enclosure has a fan to help maintain a constant temp for printing. Had a more powerful heatbed. The extruder parts were all interchangeable between the 2 machines. Made grade 5 Ti heat breaks between the heater and the Bowden tubes. Made our own Ø3.5mm Bowden tubes that allowed easier filament movement. Added a support bearing for the other side of the extruder feed wheel. Without the added support, the feed wheels were bending and causing the problems with the filament feeding. Others went to different extruders, which was still not the fix in most cases. The 2 machines have worked for 3 years now, and I wish that I had made one for myself. As I was sharing a printer, was told that there will be plenty of down time for me to print parts on it. That has not been the case for the last 2years. My son rewrote the Firmware and these 2 printers work very well and very reliably. The most accurate of parts made are more consistent than parts that were injection moulded. A tool was made to mass produce some prototype parts, and the moulders had great difficulty meeting the size and tolerance for the parts. The temp controlled enclosure is the main reason for the very consistent parts. The room the printer is in, is reasonably controlled temp environment as well.

So at some point will have to make another. Not sure if it will be the A4 sizing or the bigger A3 sizing. Lots has changed over the last 4 years of printer design filaments and type of materials for printers as well, along with some very clever combinations of localised heating for the layers, and the use of mixed materials as well. It seems that there is an advantage of a printer that can run 4 heads to make a model too.

I am considering a resin printer for smallish jobs (prototype fishing lures, model,aircraft pilots dummy engine parts and Lewis/.Spandau guns etc. so the ability to reproduce fine detail is important,

A question.,

Is it possible to halt a print halfway or maybe use pre positioned parts (jigged) such as a wire trace such that it is incorporated into the end result? (Fishing lures)

* danny *

It is certainly possible with filament printers and prints can be stopped to insert nuts, magnets etc. I can see no reason why this could not be done with a resin printer although positioning an item might be a bit tricky working in a tank full of resin. There is also the slight problem of the already printed portion not being fully cured and may not therefore take too kindly to being prodded about.

Might be worth asking the question on one of the printer forums. Prusa have a fairly active forum but not much on resin printers despite making one, the SL1 ( Prusa weren't shipping to the UK but seem to have now sorted things out. They are shipping to Australia).

John.

Edit: correct link

Edited By Journeyman on 01/02/2021 09:06:18

This has been a really interesting read with some important issues raised, so I feel inspired to comment....

At the end of last week the TV prog 'Winter Watch' showed Chris Packham and step-daughter with a 3D printed enlarged model of a spoonbill skull and beak. The piece was beautifully formed, presumably to explore the unique dynamics of the spoonbill beak in water when feeding. I sat watching thinkiing that at last here was a 3D item of real value that could have been made by any of the 'shed level' printers, providing of course, that the relelvant programming skills were present.

Personally, I don't see any practical use for being able to print plastic parts because I don't actually need to and anyway, I don't have the programming skills to do so. Were I to knuckle down to learning 'Fusion 360'...something that fills me with dread!, then I would put those skills to using a CNC mill for making my clock parts.....and I would start looking at plasma cutting equipement with much greater interest.

The really important questions here are; do computer controlled machines have a place in an 'artisan workflow' when making one off, or 'bespoke' items. Parts made on a CNC mill are no longer the product of the hand/eye co-ordination of a crafts person.....does this matter?

A few years back while I was helping to run the club stand at the London Model Engineering Ex. I had my first clock on display and we had a visitor who asked what software I had used to make the frames. When I told him that "no computers were harmed during the making of this clock" he became really angry and accused me of deliberate deception! I did'nt know whether to be pleased that he thought my work was good enough to have been made by machine, or upset because he thought hand work might be better!

It looks ‘inspired by Anglepoise’ ... but this is an interesting development: **LINK**

https://futurism.com/robotic-arm-rotrics-dexarm

MichaelG.

I wouldn't want to try embedding metal parts as the printing process for resin involves the build plate coming down to 0.05m from the FEP film on each exposure. Although it is possible to pause the print, the slightest misalignment could cause a tear in the film, or even a broken LCD screen. Perhaps crimp a ferrule to the trace and print the lure with a tapered hole through it to capture the ferrule?

As far as pilots and engine parts are concerned, that is where the resin printers shine. This is my first figure, printed on Saturday. He is to 1:19 scale, hollow, and weighs only 10g. Created, clothed and rigged using MakeHuman, then posed in Blender before exporting to an STL and slicing in Chitubox. The software is all free, and apart from Chitubox open-source, so you can try out modelling before deciding whether to get a printer.

In this case, I didn't even have to do any 3D modelling, just decide on his build and features (everything from ear shape to gender is adjusted on sliding scales), choose the clothes and set up his pose. Unfortunately this was my first with Blender for over a year (I find Fusion 360 better for functional parts), and I didn't quite get his hands resting on his legs as planned, but as things would have it the unsupported fingers printed perfectly with no missing digits.

Brian G

Some interesting comments since I posted.

I've had my 3 Pro since just before Xmas and have been learning the ropes, firstly with things from Thingiverse and now having kind of got my head around Fusion 360 I've been making simple things for my next project. I have printed the usual mods for the printer, belt adjusters, pcb cover, more rigid Z axis motor support mounts, a modded cooling fan duct etc. I've also printed some holders for my Multifix tool holders from a design on Thingiverse and as I had a few spaced left on the mounting board I designed some bins to put my tool tip boxes in. I can see the printer being very useful in prototyping bits and bobs...

My future plans are to try some linear rails, this brings some engineering input for the purists as I'll have to make the supports, idlers etc. I've picked up a pair of second hand industrial quality item for about the same cost as the (apparently) questionable quality stuff from China. A revised motherboard with quieter drivers and Wi-Fi is on the cards...

Its been a steep learning curve but good to have something to focus on and keep my brain active in lockdown and especially while it has been a bit on the cold side in the workshop.

A great result. Thanks.Brian G. Pilots and MG's quite practical.

So printing a hole to pass a wire through is possible?

As Neil asked, I am considering a 3D printer so now debating the possible use in my workshop and which type to puchase..Filament or resin.

* danny *

I have considered buying a 3d printer but can't see it being used much so I've postponed the idea. Colin

Thank you Brian for the links.

Jim

Unfortunately Bob a poor knowledge of history is not seen as a sin any more.

Spent the last week watching youtube videos on how to build one. I quite fancy having a go at a clone on the Prusa mini. I don't image I need anything bigger, but it seems quite hard to find high quality small printers. Or I might just get an Ender3 V2.

I wonder about the skill-level argument's validity.

I am not likely to use any form of CAM work; be it a putter-onner or a taker-offer of material. I use TurboCAD but my workshop is all manual-operation; and I can't learn CAD enough for pretty 3D pictures of what I want to make.

'

Nevertheless, I don't see an intrinsic problem with using such methods in model-engineering, for two reasons.

Firstly, the aim is to make something by one's own hands using mechanical-engineering knowledge and skills; and not necessarily model-engineering by the definition of a fully-functional scale model. A clock, microscope, or machine-tool accessory is not a model but the necessary tools and skills overlap with those needed to build, say a 5" gauge locomotive or 1/4-scale aero-engine.

Secondly, CAD / CAM techniques are an end to that making. They are tools, just as the hacksaw, file and centre-lathe are tools. They are also tools requiring considerable ability to learn to a level suitable for making the clock or locomotive parts.

'

I would agree that the craft hobbies should not be so diluted by computer-worship that they are devalued to merely justifying the computer or leading to inability to design and make anything; but I propose CA-Draughting and 3D-printing can be valid, high-level auxiliary skills as a part of model-engineering in all its variety.

Applied intelligently and not just as an end in themselves, I see adapting methods used in the modern engineering industry can extend the range of skills we use in model-engineering. Not diminish or replace them. It's still right to be able to saw and file a piece of steel to a line, and draw-file its surface to a beautiful satin sheen.

On that logic an 'artisan workflow' must preclude the use of any machine tools and rely solely on saws, files, hammers and cold chisels for cold working and the forge for welding and hot working. Maybe even the humble rule would be cast aside as an artificial aid. I would say such work would fall under the umbrella of experimental industrial archeology which whilst interesting in it's own right could only be regarded as a subset of what we would call model engineering. So my personal answer you your question would be no it doesn't matter.

I would however suggest that for any individual the red line between being able to say I made it myself is challenged by CNCsubtractive/additive machining. I would hazard a guess though, that few loco's are made that do not encorporate a certain number of bought in parts, if only fixings, and some many more than that so the challenge is not new

Competition entries are a whole different ball game and really should be separated out in the future so we compare like with like in different classes.

I do think it is a fallacy to imagine a golden age of craftsmen who would turn their noses up at any new tool. Most wooden planes went on the bonfire when all metal planes arrived to name just one.

Personally I like hand work but I'm blowed if 'm going to go back to rawl drills and club hammers every time I want to put a screw in a wall. Each person needs to make their own judgement as to 'what counts'.

I would be perfectly happy to see printed parts in a workshop tool but I'm not sure I would like to see them in the clocks I make.

regards Martin

Edited By Martin Kyte on 20/02/2021 23:18:09

Edited By Martin Kyte on 20/02/2021 23:19:42

Agree entirely, Martin. Then there is the situation where the item is ‘hand-finished’ only, with the main ‘rough’ working carried out by other mechanical means. Even buying in the ingredients for a model/build could be considered as using modern technology.