Sunday, 31 August 2014

Laser Engravers...To Buy Or Not To Buy?



Well I have finally put finger to keyboard on this subject and as the title suggests this subject may well span over a couple of posts, depending on any queries raised along the way.  I would confidently offer that I get asked at least once per week about our experiences with laser engravers.  The enquiries are probably a 50/50 mix of people from inside the model railway or allied hobbies, and of course people looking to add this technology to an existing mainstream signage, graphics or engraving business or those who are looking to venture into these businesses from start up.


Our business, Harlow Graphics Pty Ltd, commenced trading some 23 years ago and started off as a purely signwriting and sign-making business.  During those early years we outsourced our engraving requirements with patchy results to say the least.  I should add at this point that we have always been focused on industrial signage and engraving with a leaning towards the petroleum, electrical instrumentation and aircraft industries.  Of course these industries are understandably quite demanding in terms of materials, industry terminology, turnaround timeframes and correctness...and so it did not take long to work out, that to control all of these factors meant that we had to move quickly to equip ourselves with all the hardware and software to ensure we were in control of our own destiny...and so we embarked on an expensive "expansion program" to enable us to keep every facet of the business in-house. 

With regards to engraving...we purchased our first computerised, rotary engraving machine some 20 years ago and then moved on to the laser technology over 10 years ago.  While the graphics and digital print / sign making technology has evolved rapidly over those years...the basic principles of laser technology have moved ahead at a relatively steady pace...meaning that this years purchase is not redundant next year.


So...what is laser engraving?...well I always refer to it as "controlled cremation" and, as crass as that comment may seem...that is about all there is to it. While there are a two distinct classes or types of laser machines...we will stick to the traditional CO2 type of combination engrave and cut machines.   While a complete run down of the technology can be researched on the internet and videos can be viewed on YouTube...I will try and stick to the basics and how it relates to our hobby.  To explain the overall operation, I have borrowed a very nice little graphic from the internet and will try and keep it simple.


The laser engraver works something like a dot matrix printer but without direct contact with the material or workpiece.  There is an X and Y axis gantry with the laser "head" travelling backwards and forwards across the bed and the whole gantry can be moved up and down the table...this is all handled by the controller, software and driver and has no real direct "hand input".  The laser beam ( red in the graphic) is generated in a laser tube and is then transferred via a sequence of mirrors and then when above the travels through a lens assembly ( the blue component in the picture) to ensure focus is maintained throughout the process.

There are two main methods to achieve the process of engraving.  The first is what is called "raster" and refers to the actual marking of a material, which is achieved by the rapid backwards and forwards motion of the laser head.  This operation is again like a normal printer and as the laser head moves backwards and forwards the gantry moves incrementally ( again just like paper moving through a printer )...what portion is engraved is dictated by the graphics package you are using and the colour of the infill you have assigned in that drawing.  The second operation is called "vector" and is basically the cutting function of the machine...where the beam follows a computer generated outline or line and cuts through the material.  To reiterate...both of these functions are controlled by the software you are using...while the driver interface is used to control the power, speed and frequency of the machine depending on what material you are using and the desired outcome.

On the software front we tend to use either CorelDraw or Pagemaker  although many other drawing packages and add-ons can be used.


There is quite literally a myriad of uses that a laser engraver can offer to our hobby.  There is also a large assortment of hobby type materials that can be lasered and while the listing is not exhaustive...these include: Acrylic, Styrene, Balsa, Basswood, Most Timbers, ABS Plastics***, Cardboard, Matt Board, Paper and many many others.  I included ABS plastic in this list and while I "dabble" in this material it does have some limitations due to the flammability and toxicity when heated.  I also certainly warn against any product that contains PVC for the same reasons as ABS.

Apart from the shear versatility of the materials that can be machined is the added intricacy and minute accuracy that can be achieved.  It all comes down to your imagination and drawing capability which in reality is no hard slog with the software packages on offer these days. If I had to nail it down to one factor that makes the laser a valuable tool is that it absolutely "eats" repetitious jobs with extremely little or no clean up of the parts required before assembly can take place.

I encourage any reader to take a look back through the older posts on this blog to see what can be achieved and I also invite you to take a look at our "Laser Rail Bits" Facebook page.


I often ask myself whether I would have purchased a laser engraver purely for my hobby pursuits...and the answer is a definite NO....That may come as a hammer blow to some who are either toying with the idea or are deep in the planning stages of buying.  If it were not for the fact that our laser units already have a very hectic "9 to 5" working life and are a registered business item that allows for them to be claimed as deductions under the local tax scheme, then I would be very hesitant to invest in one purely for hobby.  Now, that direct answer certainly has wriggle room for someone who is contemplating a commercial venture or is a professional model maker...but the second hand market is littered with examples of  someone's superannuation payout and the vision of a burgeoning empire forged on the back of a laser engraver purchase.  Certainly industrial engraving is an integral part of our business and so our equipment earn their keep extremely well...but I see many examples where even a well thought out business plan comes a cropper when the unsuspecting purchaser is talked into the Rolls Royce of laser technology, takes out a lease that would make Clive Palmer blush and then witness them attempting to dream up any form of laser produced "trinkets" just to make the lease payments.

And with the above in mind ( and if you are still in the game)...I will attempt to give you some details, tips and running costs that the local laser salespeople will not tell you...

Firstly...consider matching a machine with your requirements v's your hip pocket.  As I alluded to earlier in this essay,  one of the best features of the laser world is that while the features and power output of the machines have certainly improved...the overall philosophy of the laser engraver's basic function has not changed much at this means that what you buy today will certainly see you through for about 10 years (all things being equal).

Therefore the two combinations that are of importance to any prospective buyer is the bed size (workspace) and the power, expressed in Watts. As an example...and part of our arsenal... we have a 10+ year old machine that has a bed size of 610mm x 450mm and has an output of 35 Watts...and when purchased was probably the flagship of engraving technology.  Move forward to today and 120 Watts with a table size of 1200mm x 600mm is fairly common.  The irony is that our old unit still plugs away each day providing admirable service and does everything we throw at it....It certainly is not redundant in today's world and will possibly give another 10 years of service with careful maintenance and a possibly overdue rebuild.  We are presently exploring the feasabilty of adding yet another unit to our "workforce" but the 35 Watt Epilog Helix will continue to be a handy utility machine and will most likely be our modelling unit for many years to come.

And so to the costs involved in the purchase and operation of a typical laser engraver.

Purchase Price: Anywhere between $45,000 - $150,000AUD ex GST

Service Costs: Somewhere around $500 to $700 ( Labour Only ) every 6 months for a preventative maintenance visit...Most manufacturers advise a 6 monthly inspection...but if housekeeping and user maintenance are kept up...annual service intervals should suffice. ( This is a personal must make your own decisions on frequency )

NB.  The main "consumable" parts that will require replacement are: Mirrors and Lenses ( Say $400 per set complete), Belts ( if fitted) $100.00.  The most expensive components that are a possibility are Main Control Board +/- $3000.00
And almost certainly at some point ( anywhere between 2 years and 10+ years ) will be the laser tube and indicative (present) costs to replace the existing tube in our 35 Watt unit and carry out a service...Around $8000.00 total 

Running Costs: Variable... but must factor in the extraction fan system as well as the host computer and software upgrades when applicable.

It must be taken into consideration that an extraction ( to atmosphere) will need to be installed and if in a built up area...the extracted fumes may also require filtration or water bath treatment prior to atmosphere...This is a major consideration...and on it's own could would require a separate post for discussion...


For anyone contemplating any purchase of this magnitude...research is gold.  I hate to say it but most sales staff from any of the major suppliers will offer performance and profit figures well out of kilter with actual in service use.  Of course this practice is not limited to any type of industry where sales are concerned.  While most of these guys are well intentioned and mostly reading from a well practiced sales script...The truth is that very few in the industry have had to stand over a machine in a business environment and make it pay for itself.

The local market is best served with Trotec, Epilog and Gravograph brand units and each of these outfits offers service and backup on the products that they sell.

While there is now a plethora of machines emanating from Asia ( and in particular China ) at very attractive up front personal opinion is to steer well clear of these " bargains" as the honeymoon will truly end if a major component was to expire and the owner was to look for replacements and at the very least a reputable and experienced, local company who would even consider repairing or servicing an "orphan" brand of machine... Like get what you pay for!

I must state here that everything contained within this post is MY OWN OPINION...and every prospective buyer should conduct their own research.  You may find that some businesses that utilise laser engravers will be reticent to openly chat about and offer advice regarding lasers...It is a fickle industry, with many a tad protective of their business.  On the other side of the coin...I am quite comfortable chatting to people should they wish to get an owner/operators version of the business or any other facet of the laser engraving "trade"

I hope that what I have written here has been of some use to those with an interest...and to those who are possibly now asleep over their cup of have my apologies.

Oh and please leave a comment if I have overlooked any issues that require discussion...and I will either answer via return comment...or email, phone...or god forbid...another post!





Friday, 29 August 2014

Some Weeks Are Just Too Busy...


We have been absolutely smashed with work this week.  Most weeks are busy, but sometimes the planets align or as may be closer to the truth, "misalign" and the business gets swamped.  Mind you I love what I do and am fortunate that we have a steady flow of work.

With the above in mind, it has been a slow week on the modelling front with only an hour here or there to get some progress achieved on the "shed project".  I took the opportunity to "multitask" the laser table and while carrying out some paid engraving the last of the main shed components have been roughed out.

Both side panel components and one end of the shed are almost ready for the paint shop...but a last minute lightbulb moment has me changing the plans yet again.  To add some variety to an otherwise mundane shed, I have decided to incorporate a small office within the shed and to compliment this addition of the two internal walls, a couple of windows will be added to the external panels which will mean a quick return to the laser table before the paint treatment can begin.  I will not machine up the last end wall until the other three sides are finally fitted and this panel can be cut to suit.

Tonight I have been busy making up the ridge cap and roof/wall barge capping pieces.  I decided to utilise styrene angle with .5mm flat styrene to simulate the joints.  I guess I could have used card and paper strips...but the styrene was handy and as much as I thought this would be a quicker way...this has certainly not been the case.  Nevertheless I am happy with the results and cannot wait for these to be installed following painting and weathering.

Strangely enough for such a basic structure, this project has been very time consuming and I now find myself unsure of the sequence of construction going forward.  There is much internal detail that I want to include and this will have to be done with the roof removed.  I am also giving thought to internal lighting and a couple of external "old world" wall mounted shrouded lights adjacent to the truck loading dock and forklift ramp.  Handrails and doors for the additional internal "office" as well as some rudimentary office furniture will also be it may be a while until the roof is installed (either removable or fixed). One other task is to include internal corrugated asbestos profiles (to visible walls) as the Wills product I have utilised for the exterior cladding is only one sided.  I knew this particular task would crop up...but as I am more than happy with the appearance of the chosen Wills product....this will mean only a slight imposition.

For those that are even remotely interested...All plastics behave differently when placed under the laser and as most modelling types of plastics and styrenes are not "optimised" for this type of machining...the results can often be exceedingly good or exceedingly bad.  While I am unsure as to the make up of Wills extrusions...they cut (vector) very well...but attempting to etch or (raster) the material is of little use.  I do get asked most weeks about the pros and cons of a laser for modelling purposes and I am in the process of writing a post for this blog that may be of interest to those who have a fetish towards "cremating" defenceless modelling materials.

Anyway, as per usual I have included some photos to illustrate progress and most will have to look closely for the subtle changes that have occurred over a non productive modelling week...

Roof now in place and barge capping being trial fitted...

Barge capping construction method

I will be cheating on the doors and windows...These examples are from the Tichy range

Wall panels lasered and ready for final prep and fitting


Thursday, 21 August 2014

Shed Progress...And General Banter...


There was a time when I found building structures extremely frustrating.  I always enjoyed the process, but found it hard to be patient and take my time.  Major steps like preparing and painting items before assembly was a major flaw in my approach and I tended to complete an item according to the immediate time I had available.  Obviously the frustration would set in when the finished item displayed major flaws that could have been avoided if I had shown more patience.

I am unsure whether due to age, constant disappointment or maybe just a pure self determination to improve, I now approach my modelling in a very different way.  Like most  I have a very long way to go before I will feel competent as a modeller and happy with the end result...but I now thoroughly enjoy the JOURNEY rather than worry so much about completion of a project.  Now, ironically, I do experience a certain sense of sadness when an item is complete and it is time to move on.  A complete mindset reversal from my earlier years.

The shed I am presently building is in reality a mystery.  What started out as a way to develop and prove some modelling methods, just seems to be evolving.  I normally commence any project with a firm set of plans and a visualisation of the finished article.  Not so in this case, and while this approach normally ( for me ) ends up in disaster, I am happy with progress and now with the skeleton taking shape...I can see the final outcome.  It is certainly a hybrid with the material list now consisting of cast acrylic, basswood, Evergreen components, Wills products and DAS modelling clay.

The included photos show that the "steel" structure is now complete, besser block brick-up also totally finished and as of today the concreters have been and gone and the floor is now drying.  From a roofing point of view, the trusses and all roof timbers are completed and the first completed samples of the asbestos roofing and cladding have been treated and the result can be seen in the photos as well.  A final decision regarding access has also been arrived at and this now consists of a ramp for bagged or palletised product being transferred via forklift and on the opposite end of the shed an internal, truck loading dock has been installed with rail loading being available from a semi open side of the shed.  The shed will lend itself to many industries from bagged cement to grain, flour or indeed as an adjunct to many other manufacturing type industries.   

With this project now reaching the half way point...I have also been perusing the myriad of other structures that adorn my workshop and many other locations while looking for a slot to store the shed, and while regrettable...I have reached a decision to sell many of the items.  This will be a difficult process but there is only so much that can be utilised on the layout and with the joy I get from building...I can always build another in some varied way...Any excuse to build!


Saturday, 16 August 2014

Time To Build...


With the besser block trial now out of the way, it was time to begin incorporating the end product and commence construction of a structure.  At this stage I really have no intended final position for this structure, but as the design and style lends itself to many differing types of should find a home as a complimentary structure to one of the industries planned for the layout.

The basic construction for this shed will be... besser block foundation to a suspended concrete dock level... with the skeleton being steel columns with timber truss roof frame and clad in corrugated asbestos and once I am happy with the overall material mix, the same methodology will be adapted to a few other planned industries.  At this stage, the task at hand is to marry everything together and end up with a believable end product.

To aid in construction, an acrylic base was machined with the structure footprint and column locations laid out.  This has taken a fair amount of  "site survey" work out of the project and the pre-weathered columns were pretty much a press fit into the base.  The besser panels were fitted as the columns went along...not unlike a panel fence construction.  I had visions of constructing the roof trusses from a smaller size of RSJ or ( H section steel )...but in order to move construction along and because of the fact the roof trusses will be largely hidden...I reverted to laser cut basswood trusses.

I am now deciding whether to allow for internal rail access or just stick to external with one side of the structure being open for rail loading with an awning incorporated.  Irrespective of the final choice there will be an internal concrete ramp to allow forklift access from ground level.

I have incorporated some photos of the progress to date and as can be seen the end besser panels are yet to be fitted and this will be finalised once the internal rail and forklift issues are decided upon.  I have been able to use single sided besser panels in this structure, as the inside surfaces of these walls will not be visible once the deck slab is "poured"

As the structure is progressing I can see many variations upon the theme and these could be...A smaller incarnation that could be used as a package store in a petroleum depot, bagged wheat, flour or cement...while the overall methods could be adapted for many uses.

At the end of the day it is proving to be a very enjoyable project and I am looking forward to weathering and fitting the corrugated asbestos cladding...



Sunday, 10 August 2014

All With A Grain Of Salt...


Funny how the most insignificant things can occupy, and to a degree, take over your mind.  This was the case this week with the besser block project. I certainly took on board the comments of fellow modellers and reassessed the various components manufactured thus far and upon reflection decided to trash the whole DAS clay "besser block" experiment...but as it turns out...not completely!

The moulds and stamps that had been created certainly had some basic flaws and I had to either look outside the square...or track down some proprietary off the shelf offerings...certainly not my choice of options.  I feel that the work to date had not been totally in vain, as there are definitely a few processes that could be utilised for the future...but just not this project.

While messing around with options, I decided turn out some walls using the same product as the earlier moulds had been manufactured from and this time carry out a "reverse" the most recent incarnation of the besser block walls now is laser etched and cut cast acrylic sheet.  The advantages with this material are is rigid, accepts paint perfectly (if prepared correctly), can be easily machined on both sides for applications that require visibility of both sides and the material use minimises construction time.   The mortar joints were cut a little deeper than would be normal and taking on board the methods of Iain Robinson...a DAS slurry was mixed and squeegeed into the lasered mortar joints to reduce the depth and add definition....kind of like grouting tiles.

I have included a couple of photos showing the phases of manufacture...

 Top...Directly from the laser and after first paint coat.
Middle: Following DAS slurry to the mortar courses
Bottom: Mortar joints softened with paint/satin mixture.
( Middle and Bottom example could be used according to required appearance)

   And so the weekend continued...

Apart from the above besser intended structure will also include a steel "H" frame sectional framework...or "RSJ" construction.  While I had the air brush and other equipment running...I decided to also conduct some trials on the required steelwork and reincarnate a method I have not used in many years.

The base material is store bought Evergreen extruded styrene...Plastruct ABS will give similar results with the right prep. 

Most of you guys would be aware of the "salt weathering" method and as much as I have used it on rollingstock and other flat surfaces over the years with a fair degree of success...I felt it would give me the effect I am after with the shed and I was keen to see if it was as achievable on smaller sections of material.

I have included some photos of the tests so far and I am fairly happy with the results...even on these smaller items.  It is a very handy method with a host of "methods within a method"  to achieve a great deal of variation...  and if readers would like a detailed " How To"  post to get you started...just let me know...

Showing the base colours (various rust browns) with the salt applied and the second coat being added...

Another variation with lighter corrosion spots and an incomplete paint layer...

Severe pitting and corrosion...Residual salt not yet removed... can be seen

Rust and pitting showing through several layers...


Thursday, 7 August 2014

A Sad and Humbling Experience...With a Happy Ending!


During any given week I normally get at least a couple of visitors to my "trackside" workshop.  While the primary focus of my week is to earn a living...the outside contact and interaction is in reality much appreciated and certainly takes the monotony away from my fairly solitary working environment.  Of course having an absolute front row seat to the passing parade of trains traversing the main south on a day to day basis and being fortunate enough to get a "noisy" greeting from most crews that are either friends or aquaintances is a luxury never lost on me.

Amongst the regular visitors is a bloke by the name of Leon Oberg.  Leon normally drops past while out on one of his almost daily photographic adventures to check on the latest position of a train that he is chasing. On other occasions it will be a combined visit that also includes "sorting out the problems of the world" as we see it.  Now, as much as Leon has only a passing interest in the model side of the rail hobby...he does however have an appreciation of it and is always intrigued by my latest project that is taking up bench space somewhere in the workshop.  It must be said that Leon is a bit of an enigma in this town mainly due to his almost lifelong career as a senior journalist with our regional newspaper and as much as he is an extremely accomplished photographer and prolific author of many rail related is his tenure as a journalist of long standing and his involvement in community organisations that he is normally recognised for locally.

With the above description in mind, Leon never lets an opportunity for a "story" to pass him by...and when he first laid eyes on the "G" gauge layout that once adorned the backyard here some 10 years ago, he leaned on me pretty hard to create a story for the local paper.  I resisted many of his overtures, mainly due to the fact that I did not want to divulge the location and my details for many reasons... security probably being the most uppermost in my mind...and also because I saw my little empire as a not very newsworthy subject amongst the locals here. 

Moving forward to earlier this year and during one of his visits , we were discussing his latest story in the Byways Of Steam series that covered the Captains Flat Line and I proceeded to show him the early version of the Captains Flat ore loading structure that I was working on.  Almost immediately he suggested that a story covering the "hows, whys and wheres" of what I build should be turned into a story and this time I decided to submit to his wishes...after all what damage could it do and hey it might well be a bit of fun...He immediately produced his ever present camera gear and photos of some model items were taken and a field trip was organised for the following week so he could get a better feel for the research side of things.

The next week, we met up on a perfect Autumn morning somewhere along the (long closed) Crookwell Line and amongst the chit chat he took some more photos and the "story" was roughly cobbled together. During that chat we of course discussed our families and what they were up to and as lunchtime approached...we went our separate ways and made a "rough" timeframe to meet up finalise the story.

As fate would have it...only a couple of weeks later I had reason to ring Leon as I had promised earlier in the day to update him about a train that he was chasing.  Immediately upon answering my call...I knew that something was extremely wrong...After what seemed like an eternity he had composed himself enough to describe that he had just had a call that all parents dread and the result was to ultimately change his family, relatives and friend's lives forever.  It has now been widely reported that his son Peter, was lost at sea due to an incident during a fishing trip...

The only positive to come from these "life experiences" is that you tend to reassess what is important and re evaluate the real priorities in life.  It was heartening to see the vast amount of locals who turned out for the memorial service for Peter... and the support for the family in the weeks that is a credit to the family's strength and that Leon now outwardly has returned to normal...but no doubt the empty feeling of the loss would still be close by.  And so it was with a great deal of surprise when I became aware that the story that he had been quietly and silently working on had been resurrected, completed and now adorned the pages of the latest Track and Signal Magazine...very humbling to read his offering, knowing what had occurred in the previous weeks...

As for the "Happy Ending" to this story...well, that all comes from the fact that Leon has returned to some form of normality in his life and seems to be in a "good place" presently...He is now regularly track side and has returned to writing....certainly inspirational.   For me I guess there is still a certain amount of bewilderment as to how things so prophetically changed in such a relatively short space of time from that initial decision to do this article through to now...I guess the silver lining to the whole experience has been the ability to do my little bit to promote such a great hobby....OUR HOBBY!       



Saturday, 2 August 2014

Are We Getting Any Besser???


Are we getting any closer, would be a more apt statement.  More trials to replicate besser block walls have been conducted and while I will leave the verdict of success up to you guys...if nothing else it has been fun so far!

It was very heartening to get the feedback following the last post and a very sobering experience as well.  It is always amazing how with hindsight and third party comments, the subtle flaws (or room for improvement and refinement) are pointed out and then re-examined.  I have to admit that the original block facing did resemble "face bricks" and a way of softening the faces needed to be achieved before production could take place.

This time as planned, I ran up a set of moulds machined from cast acrylic and in this case I thought it wise to use clear material so I could keep an eye on things as they progressed.  The moulds are basically a two piece affair so that when the DAS is almost dry the finished "block panels" can easily be released from the mating parts.  When I am finally happy with the overall method, a larger set of moulds will be manufactured allowing for a few panels at a time to be completed.

Upon close examination of the latest trial there is still some minor lateral "ridging" of the blocks.  Certainly this ridging is not as pronounced as the first trial and this improvement is a combination of laser settings and the choice of material for this trial.  At the end of the day the laser process does have limitations and will never give the excavated surface finish of glass.  My ever suffering wife entered the debate with a fresh set of eyes and suggested that the best idea may well be to finish sand the face of the completed components with a very fine grade of wet and dry before colouring the faces...I keep reminding myself that I married the right girl!!!

Also in this trial I have also eased up the depth of the mortar joints and will also take on board the sage advice from Iain Robinson (refer last post and comments) and look at a vey light slurry finish coat of the blocks during the construction phase.

In the end I would suggest that some of the factors I am labouring over will not even be easily visible on the completed structures and possibly what I am trying to replicate may well be readily available in plastic...but the main aim is to vary my buildings so that they don't all resemble Walthers Cornerstone kits and to also experience as many facets of the hobby as I can, while all the time challenging myself...

And so... I have included some shots of the latest attempt and in my haste to evaluate the sample I decided to dry brush the DAS clay with a base colour before it was completely dry hence the mottled appearance of one or two shots... I also note that the photos display the blocks as rather dark with the wash applied...they certainly are lighter in reality...

Enjoy your weekend!!!