SLA 3D Resin Printer #2

I have nearly gathered all the necessary equipment. Only a UV chamber left to obtain and that is on order. 

Apart from obtaining the necessary extra equipment there is some important preparation to do. First was read/watch as many tutorials that I could find. 

One of these revealed the importance of levelling the machine. I had to make some standoffs for the two rear feet due to a sloping floor. 

Another was to print a calibration model to check optimised settings. Several .stl models are available free of charge from the web for this purpose. I selected 'RESIN XPT VALIDATION' as it is low profile for quick printing.

I had previously tested the two main slicer applications Chitubox and Lychee and decided on Lychee since it fully supported both my printer model and resin (Anycubic water washable resin +) and I liked its automatic support creation feature. However, I did not need supports for this calibration model since it is flat. Having configured the default, optimised printer and resin parameters I imported the .stl file and output the printer file. 

I needed to make a heater stand (see inset picture) to accomodate the heater's power cable that sticks out the bottom of the heater. This was made using my FDM printer. The cable was then bought out of the machine via the gap between machine and its cover.

The heater does not have temperature control, just an overload cutout so,  a separate temperature controller is needed to switch power on and off to it. There is a small access hole at the back of the printer through which a thermocouple probe could pass. The probe was taped down in the gap between cover and vat near the front.

Whilst waiting for the UV chamber to arrive I decided to print the calibration model since it does not really need UV curing. The working temperature of the resin is 20 degrees C +. The chamber ambient was 12 degrees and the resin 15 degrees so heating was needed. The heater raised the resin temperature to about 22 degrees in 1 hour at which point the print was started (by the way I used a temperature measuring gun aimed at the resin for accuracy). 20 minutes later the model emerged. 

To find out whether the result was adequate I watched another tutorial about it. The model details confirmed an adequate parametric configuration, even though most of the holes were covered. I think this may be due to being printed flat to the build plate.

This is the heater I am using that fits the available space in the Creality Halot Mage printer. It is an unbranded Chinese product available from many UK suppliers.

To Part 1.

Read about my experience printing my first model here. (4mm scale Matisa Ballast Cleaning Machine & Generator Wagon).

Basingstoke Model Rail 2024

Here we go again. Our annual visit to this show.

It is encouraging to see such fine layouts and bounteous, fully stocked trade stands. The hobby is not dying! Second hand rolling stock prices were mostly affordable for anyone entering the hobby or wishing to expand their rolling stock.

What was a surprise was the ease of parking on site and quick entry. We rolled up soon after opening on the first day. Usually, we don't attend at this time as invariably the car park is full with a long queue at the entrance to the exhibition itself . Not this time. The show was busy but, without uncomfortable over crowding.

Only one layout had been seen before. My top three favourites were:

ROPLEY. Faithfully modelled from the prototype of today. Liked this as it is a station we have visited several times. Always interesting to recognise the environs of a place well known to us.

BAMFYDEL. An authentic looking, uncluttered scene and yet it is an entirely fictitious location.

GRINDLEY BROOK. On entering the first hall we were confronted with this massive layout. Its size should not be surprising as it is a large station complex constructed in 7mm scale. In fact this layout occupied the entire centre space of the hall whereas in previous years you would expect four or five smaller exhibits. Traders stands were placed around the perimeter with (by contrast) a 009 layout stuffed into the corner of the room.

7mm scale done to this level of expanse and detail  can be easier on the eye than the smaller scales. Because of this it was my personal best in show.

Only a couple of 1mm drill bits were purchased from a trader. I could not find any in the local town shops, unless I bought them as part of a larger set that I don't need.

SLA Resin 3D Printer #1

 

I have used an FDM (fused deposition modelling) printer for many years. My decision to invest in Resin Printing is to achieve finer model details compared to FDM. FDM has its place where detail is less important.

SLA (stereolithography) Resin printing is a whole different ball game. About the only common attribute is they both create models by layering the material.

Compared to FDM my research revealed:

1. PPE required (the resin is toxic)
2. Tall models take much longer to form. (all day, or more in worst cases)
3. Resin requires an operating temperature 25-30 degrees C.
4. Post processing necessary requiring extra equipment

There may be more. This is the price to pay for injection moulded quality of models without the high engineering costs.

Having studied tutorials and reviews I settled on the Creality Halot Mage. Its build area is what I need, the reviews were favourable and it is very good value for money. I bought it discounted by Creality and discounted even further using the their discount code. Another influencing factor was shipping from a UK supplier. (As far as I know all resin printers are made in China).

I am not going to review the machine as there are plenty of reviews on YouTube. Suffice to say the quality of build appears high and the user interface simple to understand and quick to navigate. Instead I'll say a few words about my buying experience.

Their UK online shop has the appearance of a UK company. It is well written in English language, easy to navigate and the buying process straightforward and delivery progress reports adequate. I assumed the sales operation was within the UK. Something jarred me though, can't remember what. 

After making the purchase I decided to check out reviews of the company and I am afraid there were some horror stories reported on Trust Pilot and elsewhere. It transpires that the sales and after sales operation is run from China and not the UK. Some people did not receive equipment, the equipment was incomplete or damaged, could not get refunds, damaged goods had to be returned directly to China. I became quite worried. Had I chosen a good supplier? 

One business day after purchase I received an email stating that my order was being shipped by Fedex on behalf of Ascent Transport Ltd. who the hell was that! Is this a scammer email? I researched the company and discovered it was a Chinese owned distribution centre located in Liverpool. Next day I received an email from Fedex stating delivery that morning. And it duly arrived two business days after purchase. Phew!

The machine was well packed and initial set up tested OK. I have yet to print because I need to buy more materials and equipment.

Purchased so far:

1. Nitrile Gloves
2. Washing tank
3. Cotton wipes
4. Resin
5. Silicone Mat
6. Funnel

To Buy:

1. Heater
2. Temperature Controller
3. Temperature Measuring Gun
4. UV curing Chamber

My only concern now, having read supplier reviews is, if it breaks down can it be repaired?

To Part 2.