3D Printing in Lockdown

Like many this year I have been “mainly staying at home”. As you can tell from the sparsity of posts I have not been doing very much either, a bit of exercise on the bike a couple of times a week, pottering in the garden and tinkering in the workshop. My old 3D printer has not been much used recently partly down to a loose print-head. I resolved to fix this by making a new aluminium backplate to get rid of the plastic frame that held the print-head in place. Whilst the printer was in bits I also decided to fit cable chains and “improve” the wiring to make the hot end easier to maintain. The outcome was only partially successful.

Print-Head Mods
Print-Head Mods

The aluminium backplate worked and held the print-head to the X-carriage securely making use of a ready made steel angle bracket from another make of printer. The wiring mod worked by inserting Molex connectors between the hot-end and the main wiring loom from the print-head assembly. Cable chains were a failure the cables not being heavy enough or flexible enough to make them work as intended.

One of the unforeseen problems was that having removed the build plate fans, printing anything small or with small details wouldn’t work. I was going to print new housings for the fans to screw to the sides of the new backplate this proved to be difficult. I am sure I would have got there eventually but being somewhat impatient I opted for a different solution. Buy a new printer!

A New 3D Printer

Prusa i3 Mk3S Printer
Prusa i3 Mk3S

I spent some time researching which printer to buy, not an easy choice. You can pretty much pay anywhere between a couple of hundred to a few thousand pounds for a smallish 3D printer but within my price bracket the Prusa i3 Mk3S consistently had good reviews and I opted for this rather than one of the many short lived strangely named Chinese offerings. At first glance the new printer looks very similar to the old but there are many differences and improvements from old to new.

I opted for the kit version of the printer, it is quite a bit cheaper than the fully assembled one. The kit of course give you plenty of insight into how the printer works for future maintenance jobs. I was going to do a write up of the build but there are so many versions on-line including some excellent videos that I decided against it. Not only that, the build manual is so good it really doesn’t need any help. Assembly is quite straightforward just read the manual carefully, and eat the Gummy Bears (Gummibär) as directed. The most difficult part is putting the print head assembly together. Many of the parts are printed, using the same printers, in Prusa’s 500+ printer farm these are all from PETG with a very good finish. The supplied hardware is also of good quality including, at least on mine, Misumi linear bearings.

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Midlands MEX 2019

EricsArt
Rudyard Kipling
Visited the Warwickshire show on Thursday and the first thing I noticed was that the usual large Warco stand was no longer welcoming visitors by the main entrance having been replaced by a number of smaller trade stands. So this year by the door was Station Road Steam, 17D Miniatures and Keith Robinson Engineering Tools whilst RDG had taken a couple of the spaces to add to their very large sales area.

There were a few new exhibitors this year one of those being Eric’s Railway Art, he had plenty of prints available to buy and was painting a new masterpiece during the show. The image from his flyer is reproduced on the left and his website is worth a look.

Another layout change was that the “lecture theatre” had moved to a screened off area of the main hall. Apparently some attending lectures found the noise from outside a bit off-putting. This also made the show area a bit smaller than normal.

Other new trade stands included: CL9UD or Cloud Nine if you prefer selling various phone related gizmos and cables; ExGlo UK demonstrating something to do with power drills; Just the Ticket traction engine and large scale rail model engineering supplies; Large Scale Locomotives and Steam Age Nameplates, were the ones I noticed.

Hall 2, where the majority of the club stands are located, seemed slightly emptier than usual although according to the plan in the show guide the layout was similar to last year but with a small competition stand placed between Wolverhampton MES and the Gas Turbine Association stands.

Working clockwise around the hall I started at the Guild of Model Wheelwrights who had one of there usual fine displays. I am always impressed by the level of detail in these relatively small models. The combination of metalwork, woodwork and other skills is incredible. I was particularly taken with the Kessler Dumping Wagon by Brian Young but the whole display was excellent. A couple of images below to encourage your wagon building and wheelwright ambitions. (Click On An Image To Magnify)

I note from their website that, sadly, the Guild is no more. Closed from October last year due in the main to declining membership. It is to be hoped that the individual members continue to provide an excellent display at the various model engineering shows for a few more years yet.

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Starting Out – Home Workshop

Well at long last I have added some new pages to help anyone who is thinking about starting a “Home Workshop”. Nothing too detailed but there are plenty of pictures and loads of links, a few hints and tips and a couple of ideas to start you in the right direction.

Blacksmith's workshop
Old Blacksmith’s Shop
There are five new pages in all covering:

Good luck with the new workshop and the many successful projects that will emanate from it.

Long Time No See

Well this is the first post in over a year just to let you know that I haven’t gone away. Life has conspired to prevent any modelling activity since the autumn of 2017. I have not been to a show or exhibition since Spalding in April 2017 and it seems unlikely that I will be able to get to any of the shows this year. I was looking forward to Bristol and the Midlands show but maybe I will get to go next year!

I have not even been able to get into the workshop very often and then only to power up the lathe and mill for a short run to keep the oil and bearings in working order. Apparently lathe bearings can distort if not used for long periods of time going slightly oval with the weight of the spindle. The only useful thing I have managed is to make some shelf space by recycling a load of old magazines, mainly MEW which if I need I can see on-line.

I did manage to do a bit of work on my 3D printer in between my “carer” duties though. I have been trying to improve the print head mounting and to install a cable chain. Neither project went very well and I now have a printer that is back in kit form having not been able to finish the work! Oh well, another project for next year. I have also been trying to write another couple of pages for the site but it is very slow going as I can’t spend too long in one session and I lose the thread, some might say I have lost the plot but I lost that years ago…

Workshop Security HTTPS

Not so much about the physical security of the workshop, which is of course important, but about the protocol change I have made to the website. Hyper Text Transfer Protocol Secure (HTTPS) is the secure version of HTTP, the protocol over which data is sent between your browser and the website that you are connected to. Google have for some time been promoting the use of HTTPS and give securely connected sites higher ranking.

The first thing you need is an SSL certificate, this has the encryption keys for the Secure Socket Layer communication setup. Fortunately even the cheapest 1&1 hosting package includes a basic SSL certificate and all I had to do to implement it was to activate it from the 1&1 control panel. The basic certificate is fine for a simple website but if you are implementing a world wide trading empire you will need to pay for something a bit more advanced.

That was the easy bit, getting the website in order is a little more tricky. To start with any internal links need either to be relative or non protocol specific that is they should look like //journeymans-workshop.uk/etc and not http//journeymans-workshop.uk/etc. Once this is done the website .htaccess file needs to redirect any calls to HTTPS this is so that all the old links scattered about the interweb end up in the right place. There are several different ways to do this and I just copied the code from the Apache site, the script conventions for these files is way outside my comfort zone! If you need to do this the code that needs to be added looks like this:-
<ifmodule mod_rewrite.c>
RewriteEngine on
# Begin Force HTTPS
RewriteCond %{HTTPS} !=on
RewriteRule .* https://%{SERVER_NAME}%{REQUEST_URI} [R,L]
# End Force HTTPS
</ifmodule>

What you should see in your browser
Browser View

With that done the next major job is to update the WordPress database so that the media links are right. WordPress stores all the links to photos as complete hyperlinks including the HTTP bit so these need changing. The easiest way to do this is with a plugin. I used Better Search Replace which is fairly simple to use and does a dry run before it alters the database. The image to the right shows the browser result when everything works but I put it in to test that the new images are stored with the correct protocol – it seems to work!

Next job is to sort out Google, as you can see I use their ads on the site and it just about pays for the hosting and domain fees. I had to re-write the XML sitemap with the new HTTPS addresses but also had to add the HTTPS version as a new site? I only have one set of files but for reasons best known to themselves Google want each version of the site shown separately. So you end up with:-
https://journeymans-workshop.uk/
https://www.journeymans-workshop.uk/
http://journeymans-workshop.uk/
http://www.journeymans-workshop.uk/
Which strikes me as a little odd but it seems to be what they want. Once this is done sit back and wait for Google to crawl everything. It is fairly difficult to check if all is working correctly and you need to keep clearing the browser cache to make sure you are looking at the latest version. Touch wood everything seems to be working. It is interesting to note the number of old links stored on the web, I was going to remove my old cign.org and cign.net sites but there are still loads of places that have these recorded.

Did I really need to do this – probably not but I learned a bit on the way and in theory my Google ranking should go up for what it′s worth.

Just a quick update, a few months after doing this I checked Google and there was absolutely nothing happening on any of the “sites” other than the https://journeymans-workshop.uk/ so I deleted the other three. Whether this was the right thing to do remains to be seen but I thought it was neater.

DTI Magnetic Base Stand

Bought one of these from Amazon for £14.99. Not really expecting too much as the real thing from Noga is usually in excess of £100.00. First thing I did was to stand it on a surface plate to check if the base was flat – it wasn’t! Quite a noticable wobble so I unbolted the arm, removed the magnet and trued up the base. The base seem to be made from two steel parts which sandwich a thick central section made from some soft alloy which I suspect is a lead / zinc or similar mix. Looks like the soft alloy is poured in hot to fix the two outer bits together. A large round magnet sits in the central hole and is rotated by the front lever so that sides are magnetised or not. It has quite a reasonable hold when switched on.

DTI Stand With Magnetic Base
DTI Stand With Magnetic Base

Put the base in the mill and machined it flat, it now sits nicely on the surface plate without rocking. Quite how you can surface grind something with a wobble I don’t know but looking at the original finish it may well have been done by hand on a belt sander. The general finish is pretty well down to the same standard. Looking at the photo you may well think the arms are anodised aluminium. Wrong, they are aluminium but are varnished with a semi-transparent lacquer. The finish on the arms is very soft and easily scratched. The black paint on the base is also fairly soft and covers a deal of filler. The clamping action isn’t very smooth so I took the whole thing to pieces and cleaned it up a bit. The arms are assembled with circlips, well bits of bent wire, there are four of them each one a different diameter and different length.

Once apart the action becomes evident, as you tighten the centre screw two wedges engage with the tapered ends of the rods that run up the middle of the arms. The rods push against the steel balls that make up the pivots. I could tell they were steel because they were rusty! The ball joints were also very rough with a good selection of dents. Polished them up on the lathe to improve the action somewhat. The ends of the push rods were also fairly rough so I polished up the wedge end using a fine diamond lap. I also polished up the wedge faces in the same way. All the originals looked as though they had been done either on a belt sander or an off-hand grinder. Also cleaned up the dimple end of the rods on the lathe using the ball to push a bit of wet and dry paper into the depression in the rod end.

Reassembled everything with some lubrication where needed and it seems a little smoother. I still have to turn the clamp knob quite hard to lock all three joints really solid but it is plenty stiff enough to support a DTI. Was it worth the money? Only just, if I hadn’t had the means to adjust it it would have been no use at all.