by JRinTawa (Started 25th September, updated to roof painting stage on 5th October 2014)
Right from the planning stage of our railway I had intended to build a typical 1900's belt driven sawmill. The likely spot was/is very close to perhaps the most used viewing and operating spot and that spot is pretty much at eye level. So much thought was needed, or perhaps that is just an excuse for procrastination, and many years have gone past with the sawmill only existing in my imagination. I should add my Dad worked as a young man in the type of sawmill I wanted to model, so I guess in small way saw milling is in my blood! Finally though over much of 2014 I have beavered away and at last the sawmill and surrounds have emerged and now others can share my imagination. |
Research
I had a few pictures in books and a very handy booklet "Small Sawmills - their erection and management" published in 1923 by the NZ State Forest Service about setting up a logging operation and sawmill. It included a outline plan of a sawmill with a belt driven "table top" breaking down saw typical of the more basic New Zealand set ups.However I felt I needed more information and while the usual internet search turned up a few more useful photos and a couple of videos most video where of "travelling carriage" breaking down saw type seemingly the common type for America
Of course we need a log being cut up....
At this stage was still thinking the roof would be fixed, but when the query was raised "will you make the roof removable so you can show of the detail" It was time to have a re think. Hmm.
However as of 5th October this is still a work in progress. More, a little more to follow.... ;-)
Higgins Park Sawmill
Finally I struck gold and was told about just the sawmill type I was after that was set up at Higgins Park museum and operated about once a month. Higgins Park is located 2kms up Pigeon Valley Rd from Wakefield, Wakefield is approximately 30 minutes south of Nelson.Link to Higgins Park http://www.higginspark.co.nz
Link to the sawmill http://www.higginspark.co.nz/museums/sawmill/
Two visits followed, the first linked with a trip to Nelson for work and on that visit all was quite at the mill but I was able to spend an hour or so photographing things and getting investigating.
You can find photos from this visit and my second visit here. Higgins Park Sawmill Photos
Working Video
With great excitement, thanks to the very helpful volunteers at Higgins Park, I set up a visit to coincide with a working day for the mill and was able to spend several hours alongside the Sawyer Brian Webby. Now I had some operating footage and more photos, measurements and a proper feel for the working mill. For understandable reasons the mill is now powered by a neat old diesel motor rather than the original stationary boiler, but part from that there is not much changed since the hay day of small NZ sawmills.
Higgins Park Sawmill at Work
The Model
I'm not sure if my sawmill will actually be called Robinson's Sawmill but it's a good enough working name for now. Initially I had thought the mill would live outside permanently but after listening to wise advice from the good fellows here on the Garden Railway Club I revised the plans and the mill has been built as a shelf queen to only be out on the railway during running secessions. This has meant that choice of materials to use in the build has widened though apart from the custom wood base most of the materials would most likely survive outside anyway.
The overall size of the mill is llllxwwww, a scale ft x ft. The breaking down saw can handle a scale ft long ft dia logs. Just to complicate things slightly the Higgins Park mill is a right handed mill, where as mine to fit the space needed to be left handed. The plan in my book was of a left handed mill. There you go, you didn't know you could get different handed sawmills!
Breast Bench Saw
So where to start? It may seem a bit back to front but I decided to start with the breast bench saw. The breast bench saw is the one where flitches are cut to finished sizes.
As you can tell most of the breast bench is made from sheet and sectional styrene with brass angle for the safety screen frame and kitchen sieve gauze for the screen grill. The saw blade is from Ozark Miniatures as are the few nut bolt washer casting used.
Jumping ahead a bit in the build, here is the breast bench completed, the riffing knife has been added.
Feed and Tailing Out Trolleys
Next up come the tolleys that the sawyer feeds the flitches throughout the breast bench saw on, and the opposing trolley the taylor-outer uses as the flitches have pasted through the saw. Both are made from various brass strip and sections. The wheels are from some old HO bogies, the leather strips to protect the workers shins are just that, leather and the bit of chain on the feed trolley is, yes, chain :-)
The Feed Trolley, it has been blacked with Brass Black which on used on most brass throughout the build.
Breaking Down Saw
On to what I suppose if the key part of the mill, and what the log meets first, the breaking down saw. Can't be that much to it can there? Just a few wooden beam, some rollers for the table to slide on, the table, a couple of saw blades and some belt drums. Hmm, and then you get into it and there are a fare few parts needed to tie it all together. The main beams, intact all the timber work, is cut down on my bench saw from Kwila decking timber. (Hehe, milling by own timber.) Kwila is a hardwood with a rather nice scale grain, and importantly according to my suppliers product info comes from a sustainably managed forest.
All timber joints are glued with Weldbond (and exterior grade PVA) and pinned with Peco track pins. The beams are xxx x yyyymm and overall llllmm long, scale ffft long.
Rollers. Nnnn rollers where needed mounted on sss shafts. All made from styrene tube, rod and channel, glued to the beams with superglue and then Peco track pins used to represent the fixing bolts.
Not having any styrene tube or rod the diameter I wanted for the roller I came up with a quick way to pair off slices of tube quickly so I could then build up the rollers from 3 progressively large dis discs. Yes it's my wife's had modelling the method. Hold a length of styrene tube in a battery drill, press up against a stop clamped in a mitre box, itself clamped on the bench. With a craft knife with it's blade extend out to fit across the mitre box now gently press down the the knife while operating the drill to slowly rotate the tube. It only takes a second or to to slice of a disc and a matter of minutes to produce loads of little discs.
Table. No pictures as I made that bit but it's just two styrene strips with angles underneath that holds the two side on the rollers. So jumping ahead slightly this following picture shows one half sitting in position and the other half awaiting fixing.
And the following picture, in a test fit our side gives an idea of how the table, beams etc work. What holds the two halves of the table so they move together back and forth? A solid section of timber bolted to the trailing end of the table, closest to the camera.Saw, Friction Feed and Belt Drums.
Part way through the assembly, in the photo below, you can see it's a real mix of what ever will look right. The saw blade and gears are from Ozark Miniatures, most of the drums are various size dressmakers domes and some bits from a empty correction tape thingie.
The belts are cut from a bike tyre inner tube. The cable on the friction feed is cotton.
How does it work in real life, best to watch some of the video, complicated to describe in words! However here is a picture of the same section on the real thing anyway!
Laying Out the Mill
With the prime components sorted it was time to set the two saws in place, think about how the mill would be powered and work on the wealth of sundry detail.
With the layout more or less set holes were drilled in the custom wood base and pegs of Kwila were lightly hammered into the holes, a good dollop of PVA glue squirted in the holes first. Once the glue was dry where possible the joints were pinned as well. In the photo below I'm part way through making the feed rollers that the flitches slide down towards the breast bench saw after being cut on the breaking down saw. What will become the mill boiler is from and LGB Otto.
The feed rollers are beads kindly donated from on of H&M's craft kits and styrene angle one a thin styrene base. As you can guess setting the height of the breast bench came first, then setting the slope for the feed rollers with the level for the breaking down saw table being set by the top of the feed rollers.
Position of rails for the various trolleys happened now (the first bit of 32mm gauge track I've ever laid). Of course thinking ahead I knew to cut a channel too. Sigh - why do we forget these things and have to dig out the channel without breaking anything!
Stationary Boiler and Mill Engine
The mill engine is an IP Engineering steam mill ending kit with a few modifications. In particular I reduced the height of the main frame I beams and shortened the length. The kit is predominantly white metal so I assembled it with full temperature solder on the big solid bits and low melt solder on the smaller and thinner bits.
With the mill engine sorted it was time to see if by cutting off some of the mouldings on the Otto boiler, giving it a coat of matt black and making up a styrene base meant to look like a concrete base if if would look like the stationary boiler I had in mind. I'm not 100%, perhaps even 80% happy with it but it will do for now.
Jumping ahead a little here is the stationary boiler and mill engine linked up. It took a bit of time to lag the steam delivery pipe with cotton but I feel it tells the story of being a steam delivery pipe than just a plain pipe.
Roof Framing and Interior Detailing
With much of the detailing tied in with, or braced off the either the columns supporting the roof, or the roof framing itself much of the remaining work happened concurrently. The columns for the roof in many early mills were just suitable logs, only later when the mill was expected to be a more permanent operation would sawn posts as I have used. Looking at some early pictures it would have be very hard to model the rustic nature of the mill building with out it falling down as I built it!
The top saw could now be done, and the balance of the drive belts.
The saw doctor's area.Safety screen around the top saw is add info made from what here
While not up to todays standard of health and safety to there was still some screening to be added so workers could step backwards into the drive belt area. I tried more kitchen sieve gauze but it just didn't look right so I splashed out on some slightly expense etched brass gauze which does look much better....and flitches on the feed rollers...
...and a flitch ready to go through over the breast bench.
With the bulk of the detailing done the rest of the rafters were added. It was a bit of a progressive thing, some rafters added with during detailing where they needed to support things like the top saw screen. Proper "birds mouth" notches where cut in each rafter so they would bear fully on each of the roof support beams.
Workers
I'm not a great fan of model people suspended in active poses but rather try to have figures in static animation. I.e standing talking rather then walking. Luckily I had on hand a number of figures from Supply Line Model Railway Figures http://slmonline.com plus a suitable Pressier figure and with a bit of heating to slow down the pose one of those suspect origin figures from China.
So the story is work has stopped while the manager shows his townie brother and sister in law "his" sawmill.
Removable Roof
Clearly I was suppose to have a removable roof because as I struck it lucky at the local model shop when he had a one off of long lengths of brass channel. With this I was able to build a subframe that would support the purlins. Each joint was bolted with M1.6 bolts then soldered. Result was a nice solid frame to work with. It was give a spray of black etch primer before adding the purlins.
Just had to try it for size out on the railway to keep me focused :-)
Jumping ahead to adding the corrugated styrene roofing. Sorry I forgot to photograph the purling stage but suffice to say they, and support blocks between were glued to the brass subframe with Ados F2 contact adhesive. The corrugated styrene I used is supplied by a small NZ supplier City Depot Models.
The styrene comes in individual sheets of scale width and length and with care the sheets can be lapped.
The bottom sheets, as you do, where fitted first. Before fitting the sheets their underside was painted to, I hope, look like galvanised irony. The bottom sheets then joined on the work bench with MEK solvent to be a become a continuous run before gluing onto the purlins with Ados F2.
To fit the top sheets a small amount had to be cut from one corner of each top sheet where the joints in the top and bottom sheets meet. Add to the fact that there was a slight variation in the corrugations in some sheets and each top sheet had to be tailor fitted. Oh yes and impressions with nails are pressed into each sheet with an awl as fitting the sheets progressed. I didn't count how many nail impressions I made in the 112 sheets of corrugated styrene used - I don't count rivets either!
In these photos the top sheets are being fitted and joints between each successive top sheets glued with MEK solvent but not glued to either the purlins or bottom sheets. With all sheets aligned I lifted the top sheets off in tow sections per side (the joint between sheet 14 and 15 on each side not glued with MEK - yes 28 sheets per row). Again the bottom sides painted galvanised iron colour and when dry glued to the purlins and bottom sheets with Ados F2.
Sorry a horrible description to a very tedious job. Perhaps on reflection using larger sheets of corrugated styrene scrubbing joint lines would have been easier. But it did work and does look good painted.
Top sheets under weight while the glue dries. My favoured bush tramway reference has more used than just reading!And yippee, painted it looks more or less okay. A bit of weathering will help though.