This one shows the big oval fuel tank in progress, the basic shape of the radiator, and the radiator fan. The engine is shown sitting on its front, showing off the pieces of lead fishing weight in the bottom of the oil pan and the cavities of the PTO housing. You see while doing test-fitting of things with the winch box tacked in place and the spar installed, the weight of the spar way out in front would pull the back of the hull up off the bench. Not wanting to trust that the mass of the various other things at the back of the yarder would keep it on the ground, I added weight to the engine...I haven't had to do that since my airplane modeling days!
This one shows the radiator mount installed, and it needs a few bolt heads added. The structure is cantilevered back and up from the base, though this photo angle doesn't show that very well. But now that it is installed, I can continue to build the radiator and associated stuff. I can do this with the engine mocked up, and figure out where to drill the front of the engine to mount the radiator fan. When that is accomplished, I will be able to locate the radiator fan shroud.
"You could probably use some armor. A Sherman can give you a very nice...edge!"
Still plodding along this weekend; more images to follow early next week. The Wichita Brakes and clutches are progressing well. I've only got a few details to do yet on the engine, but those include fabricating the exhaust piping from the headers to the turbo inlet...lots of cutting & splicing styrene tube, then reinforcing with superglue and sanding smooth. The radiator is progressing well, too, and I've started on some of the other subassemblies like the engine oil tank and coolant tank. Those have me thinking about plumbing, since a lot of that is out in the open. It also has to be flexible, so I think I'll use electrical wire of about 20 gauge and smaller. I've been looking at that on Amazon, and will order a few spools shortly. Really small stuff like 24 or 26 gauge can serve to plumb things like the Wichita brakes and clutches, and the banks of hydraulic lines under the cab. The larger stuff will work for plumbing the radiator, coolant tank, oil tank, and fuel tank. I'll model the fittings on those items, with holes drilled in the ends. I'll use the wire for the flexible lines, stripping a bit on the end and tinning it for stiffness. Then superglue it into the fitting and route it where I need it. A lot of it will probably be "disappeared" into the belly of the beast around the engine. And here's something else that came to mind this morning: For years, I've used acrylic texture gels to add mud to various Sherman models, sometimes using static grass embedded within. I need to take a trip to Michael's to select the right texture, but that stuff with some ground spices ought to do fine for the oily goo in the bottom of the hull. These yarders accumulate a layer of ick a couple of inches deep, composed of gear grease, leaked fluids (hydraulic, coolant, and diesel), dirt, and lots and lots of wood chips.
"You could probably use some armor. A Sherman can give you a very nice...edge!"
More images in a couple of days, I promise. The turbo inlet pipes are proving tedious and frustrating, but I'm getting there. I'm also working on the radiator stack (there were really three; I will have two) and exterior guard, and that's shaping up well. I've ordered several sizes of both floral and electronics hook-up wire in black to use for the various lines that have to be plumbed here and there. Not yet ordered but sorted out is several sizes of black ship-rigging thread for the winch cables. I'll rub powdered graphite on them in the end to give them a metallic sheen. The hull has landing pads added now where the vertical posts for the superstructure will sit, and I'll start cutting plastic for that soon.
"You could probably use some armor. A Sherman can give you a very nice...edge!"
Ok, some progress and some setbacks. These first two images show the radiator stack with external guard (separate assembly) and the completed (I thought)engine. I'm pretty happy with both of them. The front of the engine shows some wheels from the spares box as pulleys; I'm still a big believer in Shep Paine's "Creative Gizmology" for elements like this. The angle of the shot partially obscures it, but the big radiator reads "DETROIT DIESEL" just like it should. I used Slater's styrene letters for that. The radiator does still need a filler cap on top, and the guard needs some cutouts on the sides where plumbing will go.
The next three here show how the winch box, engine, and radiator all fit together with one another:
Notice how tightly everything fits, which is nice...tells me my proportions are reasonable. The problem is seen in image 08082, where the turbo inlet pipe on the right size interferes with the fan shroud. By the time you read this, that pipe will already be off for rework so that it doesn't extend so far towards the front of the engine. That also means that the angle and length at the top end also need fixing, so this part will probably be on the bench for finessing for a few more days. But aside from that, this part of the build is working out nicely. Once the turbo pipe is fixed and back on the engine, I can prime and paint these pieces. They might end up glued in with Elmer's for a while after that as I work out the frame that supports the top deck. I'll mask off the open spaces on the sides of the turbo, since both of those will need other not-yet-built assemblies attached there. On the right side of the yarder, the frame supports the engine air cleaner which is plumbed to the left side of the turbo. On the right side of the turbo, the exhaust will turn aft and up to exit between the vertical and angled supports for the deck. Puzzles within puzzles!
Another series of mock-ups here. I've started on the top deck and the basics there are done. Seams need to be finished and the way it sits on the hull mounting pads needs refinement, but it does sit level atop the rear winch bedplate so I'm close on dimensions.
The spar wants to orient itself a little funny when secured in the A-Frame travel lock, so that may need to be gently sliced off and moved. The deck has the square oil tank mocked up, and the overhead view shows the various access holes. The cylindrical brake coolant water tank will eventually go on the deck, and a battery box that I haven't fabricated yet. And, of course, the yet-to-be-built operator's cab in the middle. I need to build a small extension on the left side of the deck, and the spaces not taken up with various fittings will get patches of Archer's diamond treadplate.
Finally, I've started on the actuator mechanisms on the bedplate and glued those two Wichita 218 brakes in place. The hydraulic actuators are a little large, but they're what I have. They are copies of the brake actuators from the Trumpeter Chinese 50-ton tank transporter kit.
Damned if it isn't beginning to actually look like a yarder! Now, if only I could get a few more photos and some dimensions on the late-fifties Skagit-Madill yarder built on a stretched M26A1 soft-cab Pacific...but that's for the future, and another forum.
Last Edit: Feb 27, 2017 19:55:49 GMT -5 by beekster: forgot image - Back to Top
"You could probably use some armor. A Sherman can give you a very nice...edge!"
Well, there's a whole lotta orange and that's just for starters. I've dialed down the exposure so as not to sear your retinas, but that is Model Maser International Orange enamel slathered on those elements. The radiator guard needs some work, as putty still shows through on the side. I'll have to sand that and shoot some white over it before shooting more orange. This is where things on the Madill slow down for a while. It will take a week or ten days for all that glossy paint to cure hard enough for serious handling, and the next steps require most of what you see here. The big three winch drums and their associated gears all have to be shoehorned into the winch bedplate box permanently. From there I can add the outrigger sponson on the left side for the three little guyline winches, and their drums seen here are the only parts that are complete. The winch box structure also needs other details fabricated and added both front and back, and then it goes into the hull, followed by the engine. Sometime in here I have to shoot primer and some orange on the hull interior too, before the bedplate box and engine go in. Once the engine is in, I fit the air cleaner to the deck supports and make the plumbing to attach it to the turbo. Same goes for an exhaust pipe that exits from the other side of the turbo. So while this cures, I'll work on subassemblies for the spar and get the big fuel tank mounted. More later...
"You could probably use some armor. A Sherman can give you a very nice...edge!"
OK, been waiting for paint to dry and out of town over the weekend, so this has been moving slow. But here's some progress:
The three large winch drums are now permanently mounted inside the bedplate frame, and the sponson for the three guyline winches has been added. I've made the long L-shaped brackets for those guyline winches, and I've got rough blocks made for their drive housings that still need to be shaped, drilled, and detailed...lots to do. The structure in which the fuel tank sits will come off again, since it is structurally weak and sags. Better to work with it on a flat surface while finishing the fuel tank, and then put it back on. It won't be a strong element until I can glue the deck on top and glue the vertical supports to the bottom of the deck. As usual, this is mocked up for photography. I won't glue the bedplate structure in place until I have some paint on the inside of the hull and the guyline winch area is completed. It's just easier to work on when it isn't on the tank hull.
Sorry for the focus problems here, but it's hard to get the whole damn spar in focus since it is 13" long. New structures with discs on top of them are mounted up near the skyline sheave opening (on top) and in front of the hydraulic cylinder mount on the bottom. Both of those will get complicated little swiveling running blocks for two of the powered guylines, and the real ones look like this:
In scale these are .372" tall, .250" wide, and about .120" thick. The running blocks are in process and I haven't started the mounts yet, which bolt to the discs on the spar.
And I think I have it tough when I have to shave off the pour lug on Legends resin.....sheesh!
Well, I have the same issues with pour plugs when working with resin so you aren't alone. Wish me luck when I start work on my MiniMan Factory M911 HET tractor...
But you're right that this kind of scratchbuilding is its own special kind of hard work. But it is intellectually satisfying to work through the problems, and you know what they say about brain health: Keep it thinking and working on something. Normal people do crossword puzzles; I build yarders from scratch.
"You could probably use some armor. A Sherman can give you a very nice...edge!"
Post by Mark Aldrich on Mar 14, 2017 10:02:52 GMT -5
I can't believe that Dragon does not have any styrene T54E1 track shoes. I have ordered a Set of the Bronco but they are weeks out. No one had them locally or internet. Got them off ebay so about 1-2 weeks average. Not that big a deal but still erks me!
I can't believe that Dragon does not have any styrene T54E1 track shoes. I have ordered a Set of the Bronco but they are weeks out. No one had them locally or internet. Got them off ebay so about 1-2 weeks average. Not that big a deal but still erks me!
I'm actually not surprised. They only did T62 and T48 for their original LTL sets, and only added T54 as DS tracks. They had no real reason to tool up for T54.
"You could probably use some armor. A Sherman can give you a very nice...edge!"
With all that T54 track, you need to store 6 shoes on the ass end of most Shermans.
See, that's why I'm building a yarder...no track shoes to store anywhere! Also, I can use T48, T62, an T49 interchangeably and mounted backwards, just to freak out contest judges. Using CDP is possible, too.
"You could probably use some armor. A Sherman can give you a very nice...edge!"
More odd, I would say. I'd say the two are about equal when it comes to inventiveness, though. Madill also built the 171, a larger yarder, with Sherman HVSS suspension on a longer purpose-built hull. The S. Madill thread on Heavy Equipment Forums has images of the 171, and I've seen one up close once...didn't have a camera. They're not common, and there has never been one around here that I could access like I could the Tillamook 071. If I build another yarder, it will be a really old one built on an M26A1 Pacific chassis.
"You could probably use some armor. A Sherman can give you a very nice...edge!"
No, not delusions of grandeur. Having got this far on the 071 I have a good idea of what is required. The yarder on the soft-cab Dragon Wagon chassis might be easier in some respects: The engine for the yarder is fully enclosed in a box housing, not exposed like the 071. But there are fewer than a dozen images extant of the thing, and most of those crappy newspaper-quality grainy images from around 1960. Dimensions? None at all, other than it's obvious the truck chassis was stretched at least three or four feet.
Possible? Yes...I got a Tamiya DW tractor-only kit for less than $20 when Bridgetown closed two years ago. RealModel makes a resin cab. Shapeways makes improved chain drives. But that's a project for another forum, after further research.
"You could probably use some armor. A Sherman can give you a very nice...edge!"
There's also this wrinkle: The images I have are of two different kinds of yarders. The yellow one, frankly, is unidentified...the images were shot about five years ago (!!!) in BC after the RCMP pulled it over for being a rolling superfund site...chain drives with constant oil drip lubrication and all. The others show a different configuration, and Skagit Iron & Steel works did build units with one of their yarders on the Pacific with a Madill spar. Their equipment was yellow when new, and the B&W images definitely show light paint. The BC rig shown is also yellow, so may be a Skagit/Madill (Skadill, in logging circles) rig. I don't know, which is why there's more digging to do.
Back to the bench now. The little guyline swivel blocks are coming along nicely, and there's much more to do. To get back on topic, this is what the fuel tank looks like now. I still have to make a cap for the filler tube, and an oil filter & housing for the inner vertical support. The black wire fuel line will attach to that, and the line out will get routed into the bowels of the engine bay. The little brown spigot is an HO railroad brake wheel.
"You could probably use some armor. A Sherman can give you a very nice...edge!"
And things were going along so swimmingly, until this morning. Now new challenges and sequencing issues have cropped up. First, that spigot and hose on the fuel tank broke off. The culprit here is materials. I ordered a mix of various gauges of electrical & floral wire to do all the hoses & lines. The material in the image in the post just above is floral wire. It is much stiffer than electrical wire of similar size, but cheaper. Being so stiff, manipulating it put too much stress on the plastic spigot bits. I've salvaged the wheel, and shaved the tube flush with the tank so I can drill out the old rod and make a new assembly. The end of the old rod may rattle around inside the tank, but that won't matter. So, lesson learned: don't go cheap, get the good stuff. More electrical wire will be ordered from Amazon today.
Second, I will have to sort through some assembly sequencing issues and probably make some rather oddly-shaped subassemblies. Let's look at the back of the real yarder and you'll see what I mean:
Everything is cantilevered off of little pads bolted to the sills on the hull. Steel being much stronger than plastic, Madill can do that. I can't. Take that oval fuel tank and surrounding structure on the left side. No way I can glue that onto the hull and have it stay; the plastic is too weak. So that whole assembly will have to be glued to the underside of the deck structure. The deck is much lighter, and I have ways of supporting it during construction. In the end, the deck will be supported primarily at its front end, resting on the winch bedplate box...lots of solid material there. But it will make for an awkward and large subassembly. Now look at the other side. There's that cylindrical air cleaner bolted to the deck support structure. That element has to be affixed to the hull, but after the bedplate box assembly and the engine are installed for good. Why? Because I have to fabricate the intake piping to from it to the turbo. But wait...this gets better. Back to the left side, you see where the exhaust exits through the deck support frame and upwards. That is going to have to be part of the deck/fuel tank structure, with the bend down to the turbo concealed under the deck because that joint isn't going to be a pretty, finished one...can't be as it will be unreachable. All this means I'm working on several things at once, and the winch bedplate assembly is the next critical part to go in. So, I guess I had better figure out the guyline winch drum stuff on the sponson and the ancillary stuff like brake & clutch actuators front & back so that the bedplate box can be installed for good. Puzzles within puzzles....
"You could probably use some armor. A Sherman can give you a very nice...edge!"
Well, a few things are progressing but nothing photo-worthy yet. I am getting the pair of swiveling blocks for the powered guylines dialed in on the second attempt. I was an overly enthusiastic idiot the first time around, trying to make the sheave inside actually spin on an axle. That's stupid; it complicates construction and it doesn't actually have to work like the real one...I can thread it anyway. The fuel tank & top deck are coming together as subassemblies, and with the latter I have to think soon about starting on the operator's cab. I've also spent time this morning trolling the internet to solve an important problem: Turnbuckles. I will need four of them, and I need them to actually work. The real ones allow for the fixed guylines to be tensioned up on the yarder: One each at the front on the diff cover, at the right side on that triangular outrigger, one on the back behind the clutch water tank, and one on the left above the powered guyline winches. Allow me to digress a bit: The three powered guylines all run through pulley blocks at the end of the spar, and are run out some hundreds of feet away and secured to stumps. This stabilizes the yarder when it is working, along with the four fixed guylines. The four fixed ones on the yarder itself, properly tensioned, allow it to move under it's own power short distances with the spar erected.
I want to display the model with the spar either erected or lowered, and for display erected I have to support it like the real one with the fixed guylines. My materials being lighter, I don't need wire rope but can get by with ship rigging thread. But I still have to get it taut, and that means tensioning it with the turnbuckles. There's nothing in model railroad or RC car worlds that is remotely close in size. So I'll have to build my own. I originally thought plastic for the frames, with threaded rod made into open-jaw ends for tension. Nice, but weak in that the plastic could strip out. I've found that metric M1.2 machine screws and nuts are about the size I need, and about $30 for a pack of 100 each. I can superglue two nuts to thin brass strip cut to length, and Bob's your uncle there will be the bodies for the turnbuckles. I can cut the pan heads off the screws, clean the threads with a die, and glue another nut onto the cut end. Add some drilled styrene strip and I have open-jaw ends for shackles. Or maybe I use brass, if I can drill it without breaking a bunch of drill bits. So I'll be calling Minitaps in Seattle tomorrow to ask about what specific die I need to restore threads on cut ends, and then order screws, nuts, and a die. A plan is coming together...
"You could probably use some armor. A Sherman can give you a very nice...edge!"
So, virtually nothing happened last week. I spent it in the garage, detailing one of my cars and installing a convertible top control module. if you've met me, you know that I am more fanatical about my cars than I am about my models. But despite no bench time until the weekend, some things are progressing:
These two show the swivel blocks for the powered guylines. I think they look pretty close to the image a few posts above. I haven't cut that curved slot, and I might ignore that. I do have a tiny cutter ball bit for my Dremel, so I may give it a try. I'll practice on some scrap first.
I was musing above about turnbuckles to tension the fixed guylines. Below is the solution, a work in progress:
I got 100 each of these tiny M 1.2 metric screws and nuts from an outfit in Seattle for $35. These are typically used for eyeglass repair. I need four assemblies, and you see three here. The bodies are made with two nuts and two strips of brass superglued together. I tried soldering, but could not keep the nuts in place; they wanted to migrate towards the heat source. This method ought to be strong enough. The incomplete ends are two 15mm screws with their heads cut off (pan head, no slot) and a nut soldered on the end. What I have to do now is fabricate open jaws to attach to the nuts so that a shackle can be fitted. Still looking at shackles; RB Model in Poland has some that might work but they are a bit large for this application. They might work for the running blocks on at the end of the spar, though.
I mentioned ordering some thinner-gauge wire. That didn't quite work out as I had planned. This is the stuff:
It is silicone-wrapped and not as small in outside diameter as I had hoped, so I will still look for more wire (I'm building up quite the collection!). However, this stuff is really, Really, REALLY flexible, so I can use it where I don't want stress (like my problem fuel tank) or need a lot of movement (like the two connections for at the base of the spar that run back to the engine bay).
Not shown are some Plastruct items which arrived, a railing that will be used around the perimeter of the top deck and a ladder for the side of the spar. It's narrower than it should be, since it's 1/48 scale, but the mock-up looks far better than the 1/32 scale version I bought previously. Removing every other rung got the spacing between them looking better; it scales to 17.25" and standard is 16". No one but me will measure it, and it will look right. I will get the ladder finished and on the spar this week, along with fittings where the hydraulics will attach.
"You could probably use some armor. A Sherman can give you a very nice...edge!"
A little progress this week. First, let's look at the spar: This is an overall view which shows the ladder fitted and the hard hydraulic lines underneath it. The swivel blocks are in place for the photo; the mounts are on for good but the swivels themselves are press-fit.
These three show the ends of the hydraulic lines, and in one image the corresponding attachment point on the hydraulic cylinder. Yes, there were holes there before...that's because the Tillamook yarder had these hoses disconnected and dangling and I wasn't paying attention. The hex nuts were made with a really nice punch set by RP Toolz, courtesy of Historex Agents in the UK. These are big ones, but the engineering for the small ones is clever: Each punch has a guide rod alongside the hex punch tool, to ensure that the tool lines up correctly in the die. If you whack it hard enough, you'll even get a tiny little disc from the guide rod to go with your punched hex head! These are places where I will definitely use the flexible silicone-wrapped wire so that I don't put stress on these points (though the superglue which will affix them will also help secure the hex heads).
This is the rear bedplate, and I've got the band brake and linkages done for the tag winch drum. What you see is done, the band brake goes around the drum and the Wichita 216 clutch is glued onto the shaft. The drum still turns, so that I can spool thread on it.
This is the front bedplate, and only the band brake and linkage are glued down. Everything else is mocked up. I will take this apart to get paint on the bedplate before putting the gear wheels, straw drum, and four more Wichitas on there. I'll pre-paint the Wichitas before they go one, and the fit of a couple of them is a little loose so I will probably put some .005" shim stock in their axle holes to snug things up.
And with that I'm going to go dark again for a little while. The weather-guessers around here say we are in for four or five days without rain, the first such stretch since October (we're a full half-year ahead of normal on rain this season...and a normal Oct./Oct. water year is 36 inches). This afternoon I've got spring cleaning & maintenance on my pond to do, and over the weekend I'll get going on the wash, clay, polish, and wax of our trusty daily-driver C230.
"You could probably use some armor. A Sherman can give you a very nice...edge!"
At least not without a good reason. These two are the front bogie assemblies for the yarder, and they are built completely compressed. The wheels are pretty badly chunked up too, using a couple of steel cutter bits in the Dremel and a scalpel blade. I've also added the usual four bolts for the return roller bracket, single bolt for the inside of the track skid forward, and the holes in the front face, and one pair of wheels even has the service work order applied to plate over the holes. A Sherman in wartime service wouldn't look like this. Wheels this bad would get replaced, and the springs would not be collapsed. Even Jumbo didn't sag this badly. But this was common on yarders, which weighed over 42 tons with a lot of weight forward. The other bogies will be built to ensure a serious nose-down attitude.
Oddly enough, the other project on the bench will get similar treatment, though without trashing the wheels. The M31 Bridgelayer also overstressed the suspension with the bridge attached. The difference is, the bridgelayer was run that way for a matter of hours. A yarder could be in service for years or decades this way.
You weren't kidding Greg!!! They could be completely different vehicles! I imagine they are local variations eh? I like the mesh 'variant' but may go for the mix door/mesh. Many thanks for the wealth of information you've provided for this build and the corrections you've pointed out - you're a gent!
Always glad to be of help, Dick! I've been modeling Shermans for almost two decades now, and without a doubt building a Madill 071 is the most challenging project any Sherman modeler can take on. Everything but the hull has to be fabricated, and the hull itself needs alterations at the back. I'm glad I decided to tackle this, because it has definitely advanced my skill set. Of course, it's been on and off the bench for five years but in hindsight that's just how it goes with a project that goes this far into uncharted waters. Months may go by before a solution to a problem presents itself, and even then it may take a change of approach or three or four iterations before you get the result you want.
As for these machines being completely different vehicles, you aren't far off. The factory brochure I have lists the option of three or four powered guyline winches (four shown on the cover of the brochure, at the top of this thread), a cab with skylight or without, optional A/C, and three different cable diameters for the main, haulback, straw, & tag drums. Smaller diameters allowed more length to be spooled on the drum, and an operator would specify that based on the kind of terrain he was logging in and the distances he had to yard logs. The spar also exhibits variations. The placement of the brackets for the swivel blocks on the top & bottom of the spar isn't the same on all yarders. Madill apparently had more than one standard spar design, so that might account for that difference. It could also be a result of an operator torching off the thing and moving it. With the engine door, I'm sure that cooling was an issue in some locations and a more open design facilitated air flow. The water-cooled clutches and brakes could get pretty damn hot. Add to that the oil cooler for the torque converter, engine, and possible A/C and that makes for a lot of heat that has to be dissipated. Interestingly, the transmission apparently wasn't cooled. Of course, it was only in use when the yarder was being moved, so it probably never got very hot.
"You could probably use some armor. A Sherman can give you a very nice...edge!"
Time for another update. Things are progressing in fits and starts, but things are happening as shown in the photos below. The winch bedplate box and the engine are now permanently installed so that other things around them can be fabricated. The top deck has been glued to the oval fuel tank structure, so that it sits on the rear bedplate and the hull pads. It doesn't sit flush on the right side of the bedplate without pressing it down; I think the structure is racked a little because it is so light. Superglue in final assembly ought to fix that.
The screened engine access door is also permanently affixed to the rear bedplate, and the right rear vertical support for the deck has been glued to the hull. I added a brace below the door to tie the rear vertical supports to the bedplate for strength, and used that stringer and the door to hold the vertical structure in place while it dried. The yarder I measured had no bottom stringer, but others did. Once the vertical support was dry, I put the model on it's rear and added the air cleaner.
The front side is still largely mocked up. The gyrations required to get paint on the front winch bedplate were too much for the band brake that goes around the small tag drum, so I have to rebuild that before I put that drum on for good along with the Wichita 216 clutch in front of it. The overhead shot shows where the air cleaner sits, and it has yet to be plumbed to the turbo inlet. In the background you can see the bottom of the deck structure with the fuel tank.
If it looks like I'm entering the final stretch on this one, allow me to shatter that illusion. Among the things left to do:
Make an exhaust pipe that runs along the bottom of the deck straight aft and then up, and work out how to make it line up with the engine. Add details to the top deck, including treadplate and guardrail. Build the operator's cab. Build the front irregular box structure to cover the clutches and gears. Add guyline attachment lugs to the hull. Build the structure for the powered guyline winches that sit atop the left side sponson. Get some brass shackles and finish the guyline turnbuckles (order to RB Models in Poland happening this week). Add the radiator and plumb it to the engine, square oil tank in the deck, and other places. Fabricate and add fuel filter & plumbing to the oval fuel tank. Add a couple of hydraulic oil filters (and plumbing) and a fire extinguisher to the rear of the fuel tank support structure.
And more that I'm probably forgetting right now...
"You could probably use some armor. A Sherman can give you a very nice...edge!"
Well, since I've been on vacation for a week and consumed with the usual chores that precede and follow time away from home, there's not much progress to report. While I was gone, my order from RB Model in Poland arrived with nifty little brass shackles. The ones I thought might be useful for finishing the turnbuckles might not be quite the thing, as they seem too large (though they are the smallest ones RB makes). These, however, are just the ticket:
The two seen here will be joined by another, and these will hang the yet-to-be-built sheaves for the powered guylines from the spar end. I will have to modify these, since RB only makes them with a non-threaded shank on the pin. They are secured with a bit of wire through a hole in the shank of the pin. I will don my Optivisor and add hex heads to the large round end of the pin for a more accurate appearance, and will probably do the same for the other end too...punch the hex heads to size, laminate for thickness, and drill a hole for the pin. Probably add a round washer there too. This method will look more like the real thing.
So this week I'll keep moving on the box cover for the front of the yarder, start in on the three guyline sheaves I need, and try to find a solution I like for finishing the turnbuckles so that they are strong enough to keep tension on the fixed guylines and hold the spar erect at the proper angle. Styrene strip is easiest to work with, but I'm not sure it's strong enough. I may have to use brass strip instead. We shall see...
"You could probably use some armor. A Sherman can give you a very nice...edge!"
OK, so this turnbuckle thing might not be as difficult as I believed it to be. Below are images of the prototype and of my rendition:
Mine is somewhat different, of course, but it is made from brass strip for strength. It took an hour to get this first one done; the other seven will go somewhat faster. Drilling takes a while, and so does grinding & shaping the rounded ends of the jaws. You see some solder residue where I tried to solder these parts together, but I can't reliably fixture them so after the first try messed up one of the screw ends I made a fresh one of those and superglued the jaws onto it after filing the mating surfaces smooth. This method ought to be strong enough, since superglue is strongest when subjected to the kind of pulling force that will be applied. The force of holding up the spar will also be distributed among four of these assemblies, so the load on each one isn't all that large. This jaw is OK and I'll keep it, but I will try to get the others to have a slightly narrower opening in the jaw. After the superglue has set up good and hard I will slap a little primer on and use files, sanding sticks, and more superglue to refine the shape of the joint at the base of the jaws.
"You could probably use some armor. A Sherman can give you a very nice...edge!"