Volvo G990 Grader

[9W Monighan]

Pretty tricky work cutting that ring to fit inside of the circle. I do that alot at my work on some of the products we build.

[Stefan]

Can sure agree on that. I actually calculated and marked the length to cut before bending. The first cut was just a bit too long (and luckily not too short).

[9W Monighan]

Originally Posted by Stefan

Can sure agree on that. I actually calculated and marked the length to cut before bending. The first cut was just a bit too long (and luckily not too short).

If you think on the lines of the neutral axis of the piece your cut length will come out close plus the flat material on the ends . When you bend something, the outside area is stretching and the inside area is compressing. When we bend and cut an arc we calculate the circumference of the web were we can wrap a tape ruler around and cut to size.

[Stefan]

Yep, I meant the length of the neutral axis . Btw, what dimensions are we talking about in your case?

[Stefan]

Here some "making of" pics. First the brackets for the blade tilt cylinders.

The original. Actually, I just realize I forgot to round of the outer corner Well, better that than rounding of something which should be well defined.


Cutting at an angle saved some material.


Getting the top surface of the pieces parallel with the top of the jaws (having made sure the latter are at a right angle to the spindle axis).




Later, same procedure but new set-up for drilling.


1.2 mm drill.


Tapping M1.4. Always quite scary tapping the smaller threads in stainless 1.4301 (SAE grade 304), since this material has a strong tendency to work hardening. But I need it for its weldability.


To be continued. Thanks for looking.

Stefan

[mazdaparts]

looking good. Wish I had a thimble full of the talent displayed in these projects.

[Stefan]

Some more circle making pics. To start with a "quick and dirty" jig for adapting the bracket base to the radius of the circle ring.







And another setup for rounding the bracket ends. The center of the bracket hole is offset by 0,5 mm from the center of the turning table.







Each bracket was provisionally fixed with two welding spots to a circle arm.




Here the brackets have already been hard soldered and the circle arms are being connected with a 16 mm rod.


Thanks for looking.

Stefan

[D8R]

A lot to do 1 model, here´s 2 at the same time! guess you will have spare parts for rest of life, ha ha.
dan

[Stefan]

Yeah, Dan, assuming the build itself doesn't take rest of life...

Sometimes I wonder whether making two was the wisest decision Now, having come this far, I will, and I'm still motivated to, continue not only building both models, but doing it more or less in parallel, since repeating all steps later for the second model would seem to be less efficient.

Stefan

[gipicarto]

[Stefan]

The tandem bearings are ready. There´s a split outer ring attaching to the tandem box, an inner ring attaching to the rear axle and a bronze ring there between, fixed relative to the inner ring. The bronze ring has the same dimensions as a certain "standard" 4-point contact, thin section bearing with a split inner ring. Unfortunately, however, the only supplier I know of couldn´t deliver .

To the left the two faces of the outer ring.










At the end I decided to split the bronze ring and make a one-piece inner bearing ring.


Finally, everything fits.



Making of

The bronze rings were made first, to allow for easy test fitting with the other rings.










The main outer ring portions being parted off.




Test fitting during grinding.



The stub was barely long enough for machining the other outer ring portions.


I hate making thin things. Either you have this rather insecure and hard to adjust grip or you have to make a jig.




This threading apparatus is really an excellent tool.


Thanks for looking.

Stefan

[Hemi1966]

Once again, excellent job Stefan. I don't have any more words to praise your work

About the threading apparatus for how small tap can adjust it ?

[Stefan]

Originally Posted by Hemi1966

Once again, excellent job Stefan. I don't have any more words to praise your work

About the threading apparatus for how small tap can adjust it ?

And once again thanks, Hemi. This morning I didn´t have the appropriate words for your X-frame , that´s why no comment

As to your question: My device from Vertex (VTA12-JT6) officially takes M3 to M12, but I just test inserted an M2 (shaft dia. 2.9 mm) and an M2.5 (shaft dia. 2.7 mm [sic]) and that seems to work too (for the M2 only the threaded portion was visible). For the smaller taps the lower limit of the adjustable torque might be too high, but I still think it would work for M2 in aluminum. According to the user instruction there´s a smaller model (VTA7-JT6) for M2 to M8.

Stefan

[Hemi1966]

Originally Posted by Stefan

And once again thanks, Hemi. This morning I didn´t have the appropriate words for your X-frame , that´s why no comment

As to your question: My device from Vertex (VTA12-JT6) officially takes M3 to M12, but I just test inserted an M2 (shaft dia. 2.9 mm) and an M2.5 (shaft dia. 2.7 mm [sic]) and that seems to work too (for the M2 only the threaded portion was visible). For the smaller taps the lower limit of the adjustable torque might be too high, but I still think it would work for M2 in aluminum. According to the user instruction there´s a smaller model (VTA7-JT6) for M2 to M8.

Stefan

Thanks for the information, I always thought that those tapping devices don't work with so small taps, but apparently I was wrong.
May I ask where did you by yours ?

[plow jockey]

Your skills are amazing ,a true artist.

[Stefan]

You´re welcome. I bought mine from Wabeco at a fair, but since then I saw it much cheaper (for 199€ - 30% off) somewhere else (don´t remember where), so search carefully.

[Hemi1966]

Originally Posted by Stefan

You´re welcome. I bought mine from Wabeco at a fair, but since then I saw it much cheaper (for 199€ - 30% off) somewhere else (don´t remember where), so search carefully.

Stefan, thanks again for the information of the tapping device, got mine few days ago and it works great I purchase the Vertex VTA7-JT6 from Ebay.

[Stefan]

Can imagine it served you well during the excavator track build

I on the other hand haven´t spent much time in the workshop lately (My wife had some other plans for "us" and the house after the summer, something which will still take some months). Could occasionally sneak into the workshop, but have only managed to turn the end caps and started making the front inserts for the cylinders.



What looks like a shadow in the right uppermost (finished) insert is actually an O-ring (11/1 mm).


Stefan

[speedy8305]

This is definitely a build to watch I love the detail I must say all you guys that work with a lathe and milling machines are very talented

[Stefan]

Sorry "speedy8305" and everyone else, it has not been so much to watch lately, but I did manage to make some more parts for the cylinders.

Here the circle drive cylinder parts. Only the cylinder brackets are still missing. Of all cylinders I´d like to finish the circle drive cylinders first in order to be able to perform tests and find out whether the control valve can be made to scale (if at all ).








Stefan