More Madill Madness

[Beekster]

Well, I thought I had the interior done. Not so much. Got to looking at it and something didn't seem right, so I reread my crib sheet on dimensions. Insert numerous expletives here...I miscalculated the size of the big square crossmember; it's more like 8.25 inches rather than 6. It's been ripped out, and when nearby orange paint is dry I'll clean up the area for a new one. I think I can use the lower piece and the angled supports, but I know better than to make silly errors like this.

[JCON]

You'll get it there!!!

[Beekster]

Yeah, Joe, I will. In hindsight, the odd shape I had to make for the guard on the middle Main drum should have tipped me off that I had something wrong. I have to let paint cure for a few days before I can do more demolition and begin restoration work. I can fabricate a new crossmember, but now that the removal of the wrong one has improved access to the area I will slice out the oddly shaped guard and drop out the middle drum to start over. In the meantime, I can start in on the spar hinge mounts, guyline outrigger, and spar saddle.

[Beekster]

This is better. I've rebuilt and replaced the transverse support between the Skyline & Main drums, rebuilt the guards for the Main & Haulback drums on the inner face of the rear bedplate, and mocked up the in-progress spar hinge and spar saddle. I've also cut down the floor and turned down the bearing on the back side of the Main drum so that with a little fiddling, it can be inserted from the bottom at a later stage. I'd rather not have to paint around it. Speaking of which, I have only a partial bottle of Model Master International Orange, and I need some yet for the Hitachi excavator. I'll be using standard Testor's orange in the little bottles, which is a bit lighter & brighter than the now-discontinued Model Master color. The little bottle color is probably a better match for a recently rebuilt unit anyway.








With the floor cut down, there actually isn't a lot holding this subassembly together. Keeping the dummy shafts in place keeps the thing from racking while being handled, so they'll stay while I work on the right side outrigger and the left side sponson. Adding those will eventually add to the structural rigidity of the assembly; the sponson ties both sides together and I will modify the outrigger to do the same based on reference photos. Adding a beefy brace or two is a pretty common modification.

[JCON]

Looking good!!!

[Beekster]

I've been working on the guyline outrigger the last few days. I've photographed several that have an additional support welded to the front winch bedplate, angled back and bolted to the rear winch bedplate to make the structure stronger. Often those are thoroughly bent and thrashed, but mine isn't since the machine will be shown as relatively recently refurbished.






The addition of this brace seems to almost universally be found with another modification, a reinforcing crossbar between the bedplates at the top with a large angled bracket that's drilled for a shackle or another guyline turnbuckle. I've added those features too. The roughly triangular plate for a pair of turnbuckles had a duplicate, and I will rig the model differently from the first one, like this:


This arrangement doubles the strength of the guyline mount on the yarder and connects up to the lug nearest the Main & Haulback sheaves on the spar. The additional mount seems to be an alternate anchor for the mount usually seen at the very back of the deck, or an additional one.

[JCON]

Good reference pics indeed!!!

[Beekster]

I am sure that to those observing this build, that progress sure seems awfully slow. Well, that's because it really is that way. For example, these are the Wichita clutches & brakes under the front superstructure:

And the rear, where one is missing:


There are a total of seven of these things, which differ in their front details for modeling purposes.

Each of these is a sandwich of material, so making them is tedious. This is the result of two hours' work:


Each disc is a lamination of two pieces of .030" stock, cut from sheet stock using the Olfa circle cutter in the background. The tool doesn't make the cleanest circles on thick material, but that doesn't matter. All of these are a good .050" oversize and will be turned down to size on my lathe in the garage (which needs some rust polished off the bed and some fresh oil applied). Each assembly required two of these laminations, plus a thinner one at the back that I haven't cut out yet. If you count the bolts on the front face, you'll see that there are twelve. That means each layer has a dozen pieces separating these laminated discs, or 24 per unit. That's 162 pieces, and I haven't started chopping those out yet either. Once each unit is together, all of them will get superglued onto some .125" brass tubing, which I will chuck up in the lathe using a live center for support to keep the work from deflecting too much. Then start turning everything down to the desired OD. The two units that have the recessed fronts will each get chucked up again to open up their centers and file in the shallow bevel. Once all the lathe work is done, the rest of the surface detail has to get done and the individual assemblies drilled to match the diameter of the shaft they will be attached to.

These are probably the most complicated elements to model, but there are others that also demand a lot of time: The instrument panel, the cab it sits in, the fuel tank, the PTO housing, the engine, the deck & superstructure. Oh, and there's a hull to build and a track frame to cut up and modify, too.

Yeah, we'll be here a while and if the first one is anything to go by, there will be breaks in the action from time to time.

[Tobi]

With such great reference pictures for weathering, you should overthink your decision to make a rather new machine.

[Beekster]

Apr 30, 2022 3:48:18 GMT -6 Tobi said:

With such great reference pictures for weathering, you should overthink your decision to make a rather new machine.

Check out my first yarder build here, Tobi; it's in the Completed White Stuff area.  That one is beat up and grimy enough to make anyone want to keep their distance, and believe me it would be possible to go even further than I did on that one.  I chose not to bend the deck supports or dent the big fuel tank or a dozen other kinds of damage that these things accumulate over years of working in the woods.  I took the vast majority of these reference images myself when one of these machines was parked for several years just an hours' drive away from me.  Whenever I took a day trip to shoot pictures and take measurements (and I took several such trips) I brought a change of clothes just in case.  I managed to avoid getting thoroughly covered in oil & grease (and stung by bees on one trip!) but you can't crawl around one of these machines without acquiring some of the goo.

[Beekster]

More progress on this one lately. I've built the left side sponson, and the long L-shaped beams that support the powered guyline motors are setting up now. I haven't started on the motors yet. On the back face of the rear winch bedplate, I've detailed the band brake that controls the speed of the Skyline drum and added the cover plate that accesses the bearings. There's an identical plate on the front face of the front winch bedplate, so I built them both at once and set the other one aside for now. I can fit all the gears that are covered by the front superstructure, and a couple of them even mech well enough to turn each other if I spin the shaft! That's just lucky. I am aiming for at least as much detail in here as I put into the first yarder. This one will have a different shape to the superstructure as a result of being on a new hull & excavator frame, so there might be different sight lines into the area or I might make an door that actually opens. We'll see what happens, but I'd rather have more detail in case things can be seen than to find out later I ought to have added something and finding it impossible to do properly later on.





The drums are once again mocked up, but now all three of them can be dropped out the bottom with no drama and reinstalled just as easily. The inside of the winch bay is now ready for paint. If only it would stop raining and the humidity would go down. Just finished the wettest April on record in Portland, following above average precipitation for the previous three months, too.

[JCON]

One day at a time brother!!! You are getting there...

[Beekster]

Here is another one of my indispensable tools, even if it doesn't get used all that often. Behold the Sherline miniature lathe:


Thirty years ago I worked for a company that made scanning ion & electron microscopes, and we used these machines. Actually, all we used was the headstock & bed; we would chuck up cylinders of molybdenum and use several grades of aluminum oxide paper to polish them to a mirror finish. When a change in manufacturing processes meant that we no longer had to hand-polish lens elements, these were declared surplus and I snapped one up, along with a couple of spare motors, the transverse tool bed, the tool steel cutters, and the tailstock. I bought the live center in the tailstock myself. Seen here are the four guyline winch drums, superglued to a piece of .125" brass tube and the operation to turn them down has just concluded.





For operations like this, the cutter isn't needed and nail buffing sticks will suffice. I get mine at Sally Beauty Supply; these things are about a buck and a half apiece and last quite a while. Once the work is done, some superglue debonder and work with a scalpel and some twisting will soon get the work to come loose from the brass tube. Then just sand off the remains of the glue and wash the parts and the job is done.

If you keep the lathe in good shape, you can do some really fine machining with it. Mine, as you can see, is spotted with rust (you should have seen it before I cleaned it up & oiled it again this morning...). It was also rather worn when I got it, but real precision work isn't necessary for what I do. Most of what I mill is plastic, and occasionally brass. It's accurate enough for models like mine since I'm not trying to machine working metal parts to a fine tolerance like you would if you built a miniature engine. For scratchbuilt things that need machining, a lathe is worth having. I haven't done it, but there's no reason that you couldn't turn your own metal gun barrels with this tool. Getting a constant taper is a challenge because it's a manual feed for everything, but with some real machinist skills and good coordination it can be done.

[JCON]

Very nice tool!!!

[Beekster]

Here are most of the brakes & clutches either complete in rough form or being assembled on the fixture:


Several have crude notations scribed in and picked out with a little paint for visibility; this is to readily identify each one and those are the back surfaces anyway. One subassembly is incomplete on the fixture showing how I layer things together to build up the structure. As you read this, that assembly and a duplicate are now complete. Those are the last two, and when all the plastic cement has cured I can superglue them to the brass tube and start milling on them with the lathe.

Note that the assembly fixture has one side longer than the rest. That's intentional. That is the 12 o'clock position so that I can get the first four of the small bars aligned properly. The other eight shorter ones get adjusted by eye, and the same goes for each layer as the assembly is built up. Such fixtures are easy to make and really help keep things square and true.

Once the machining is done there's lots more to be done to these. The base will get the circumference built up with strip stock to make a flange for the mounting bolts; details need to be added to the front faces, and more bolts added there too. These are going faster than the ones on the first yarder, but there's still a lot of time involved.

[mustang1989]

Jeez!! I can't wait to see more of this brilliant work.

[Beekster]

It's bloody cold out in the garage today, but nevertheless I got the five larger clutch & brake assemblies milled to a constant outside diameter.


As you can see, a lot of the holes are hard to discern now, being obscured by junk produced by the milling process. Next step is a thorough scrubbing with soap & water and a toothbrush, alternated with scrubbing with a wire brush. That will get most of the gunk out of the crevices. Then work with the debonder & old scalpel to work everything loose and off the shaft. Finally a lot of work with needle files & scalpel blades to clean all the openings. Meanwhile, the other two assemblies will get milled down to their proper size, which is two scale inches smaller than all these, and they will follow the same clean-up process. Two of the units seen here, the Wichita 218 brakes for the Main & Haulback drums that live in the engine bay, will have to go back to the lathe to have their front faces bored out to the larger diameter and a depth of about an eighth of an inch, and the gentle bevel done with a needle file.

[mustang1989]

Cold is not easy to deal with when trying to work.  

But you're doing some amazing work here.

[JCON]

Great job Beekster!!!

[JED]

Amazing work Beekster