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I had some time over the last week  and decided to test if block filler will hold the blocks shape similar to a torque plate after the head has been removed. 1, 3 and 5 were measured at 9 points each before and after. MY goal was to see how much impact a torque plate has on the shape of the bore.

The first set of measurements were taken with the main girdle and head off with no filler. The block was then filled with grout up to the water pump (half fill) and the girdle and head were torqued to spec. The block sat leveled for 7 days and was disassembled. The second set of measurements were then taken.

Results are presented as the delta between the original and new value. All values in the PowerPoint are presented in inches because America. The largest changes were 0.0035 in or 0.0889 mm between cylinders 3 and 5. There may have been even greater changes if the block was filled to the top with grout.

I hope this information is useful and I'm curious to hear what you guys think.

 

 

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Notes:

My block had the most wear in cylinders 3 and 4. Due to the amount of change in 3, I measured 2, 4 and 6 separately. 4 was also all over the place. 6 was similar to 1. They were not included to keep the test objective.

 

 

  • Like 1

I think you'll find we're confused about what you were trying to do and how you were doing it.

I would have thought that block rigidity was something you measured while loading the block in beam or in torsion, and that you would do so before and after grout filling, to see if putting material in there created a "composite" construction with the expected rigidity increase. Notwithstanding that the true function of grout is less about gross rigidity than local (ie preventing bore deflection/splitting and tying the bores to the main bearing locations a little better, etc etc).

It is nearly impossible to follow your description of what you've done without closing ones eyes and making "aliens" hand shapes in front of oneself to try to follow the manipulations you've made.

It's still unclear to me what you were trying to prove.

  • Like 1

I didnt present too many conclusions because I wanted your opinions and feedback based on your own experiences.

I don't know the exact material, but it is similar to concrete and therfor only has valuable strength in compression. The forces on the set material once the head is removed would mostly be in compression since the grout wants to retain its shape and the block wants to return to its relaxed state since it's still within the elastic region. The grout would theoretically make the block more rigid. The exact amount would take a better setup on my end.

Thought experiment: Instead of aliens, twist your favorite fleshlite. Now fill it with grout and allow it to sit for a week. Now try to twist it again. Observe what you see. Now get your other one and blow into it. Observe what you see. Now put it into a can and fill the space between your fleshlite and the can. After it sets blow into it. Less movement in torsion and less expansion i hope. 

 

OK. But what about parts of the block that, when assembled, were twisted into a position that pushed into the void space, which, when disassembled, then released that force and opened back up, thus putting the grout into tension? Would effectively just pull the cast iron off the grout at the interface, leaving a tiny void and benefitting not much at all.

Swings, and roundabouts. It's like putting something tiny into the fleshlight and finding out you needed a smaller one, to perhaps follow your area of expertise.

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