Volvo G990 Grader

[D8R]

Looking good Stefan. Can almost see the smile on your face when putting the parts together. Will parts be TIG ' ed together?
I learned from my model that if MIG 'ed it was easier to have the fingers a little shorter, more room for weld in hole.

Dan

[Stefan]

Thanks! I'm glad you realised that, Jens. However, this time it was necessary to file a little bit on the fingers after the bending before everything would fit .

Dan, I usually spot weld using the TIG and afterwards the rest is hard soldered or glued (where strength is of less concern). I haven't actually learned TIG'ing and prefer to just fuse together touching parts without adding any additional material and therefore it's actually good to have the fingers a little longer to have some spare material for TIG filling the gaps where the fit between the finger and the notch is not prefect.

Stefan

[Heavy Metal Doctor]

Top notch work! A lot of the 1:1 equipment I work on have parts built by the same tab / notch system -- makes welding everything together fast and accurate.

[Stefan]

Thanks! That´s really interesting. I didn´t know it is actually used in real life 1:1.

[Stefan]

I have now started assembling the "quadrants", i.e. the immediate supports for the grader blade. This is the original right side quadrant:







Here the left side one:


And here my 1:8 attempt:


























Stefan

[Hemi1966]

Stefan, I´m speechless

[SmallHaul]

Amazing work!

[Lil Giants]

Alot of intricate parts... your head must be spinning at times!!!

[dirtpusher9]

Nice work. This thing will be indestructible.

[Stefan]

Thanks guys!
@ Lil Giants
You are right, it´s mostly spinning Despite a 50 page document with notes for all parts and some excel pages.

Here a few close-ups of parts for the articulation:




The two center bolts (M3) and their nuts will be replaced by ones having a scale head.







Edit: The rear eyes for the articulation cylinders are combined with the rear axle supports.

Stefan

[Stefan]

I made some additional brackets and fixed them to the quadrants. As you´ll notice, the outermost parts of the bearing holders have now been attached. Today I´ll hard solder the joints.







At a late stage I noticed that there is a recess in the quadrant for the cross bar, so I added that to the model (adding by removing ).


Stefan

[D8R]

Soldering the joints looks realy good, did you have a owen to heat the parts (I don´t see any darkening in material from heat)?
And you used TIG to position the parts before soldering them together?

Dan

[Stefan]

Hi Dan, I already polished those parts rather thoroughly. Next pictures show the same parts after final soldering and acid cleaning in 25% vinegar with salt for some hours but not yet rubbed (which I´m not going to do this time, as they will later be sandblasted). They are a bit darker but right out of the torch they looked pretty ugly . I use an oxygen/propane torch. And yes, they were positioned with the TIG, some 70 amperes for 0,5 to 1 seconds.





Stefan

[Stefan]

Hi, below some pictures from the build of the front frame.











































Stefan

[Brian in PA]

WOW!!! This is amazing! Great work. your moving along good too.

[Espeefan]

Very interesting! I get so used to seeing guys machine all these great models that I forget all about the possibility of laser cutting parts, and welding them together. Seems once you have your parts, the build would go a bit quicker then having to machine everything. You're making excellent progress! Keep it up.

[JensR]

Agreed, although we should not forget that the skill to design something like that in CAD in a cost-effective and functional way is also considerable.
Ideally, you'd still need have some machined/turned parts, like Stefan's axle carriers.

For smaller scales/models, I think you might find that glueing degreased metal offers more than enough strength, especially if you take it into account during design.

[9W Monighan]

Very nice hard soldering joints. Looking like a 1:1 machine with all those weldments. Modern machines such as this are built from welding plates together. Much cheaper than yesterdays iron casting for everything. I'm stuck in yesterday with my antique machines; Riveting,casting,bolting, and sometimes welding.

[Vanisle]

That's a great idea for building, using the tabs. It is inspiring to see what can be done. Any idea how long it might take you get this completed? Do you think the building process is going quicker with the tab design? Sure seems like a solid design.

[Stefan]

Thanks for the comments guys!

@ Espeefan & JensR: Yes, as 9W Monighan said, the real one is mostly plates, and since there is in any case quite enough work to be done, I decided to have most of the plates cut in a laser cutting shop. But some parts, like the hose bundling plate, I did myself What to do yourself is of course a trade-off question between time, money, difficulty and fun, but in the case of the plates, everything speaks for having them done. I´ll give you an example, for the moldboard slide guide I´ll need four stainless strips (for the two models I´m building) 487 mm x 9 mm x 1,5 mm (about 19” x 11/32” x 1/16”). Not a big deal, but also not much fun and only four bucks apiece from the cutting shop...

Even by the size of my model there are several small-strain-to-area-ratio parts for which gluing will be quite sufficient.

@ Vanisle: Someone in this thread said that the tab concept is used on some of the real machines, too. And yes, I reckon it´s much faster for a given accuracy (at least the one I want), in particular when you take advantage of the inherent accuracy of laser cutting. Just think of it - once the parts are made you can put them correctly together almost blindfolded.

Regarding the time to completion I´m sorry: What you see started almost five years ago and is surely bound to take another five, if not more (but positively seen, I´ve saved you five long years )

And here´s the hose bundling plate (never shown to anyone, anywhere before ). It´s used at the waist of the machine.