Finalizing Main Table Alignment

[dusty]

You can sneak up, yes but only on two of the bolts. The other two are not accessible until you can tilt the table.

I may try gasketing the interface between the trunnions and the table. A soft gasket just may prevent the table from shifting as the trunnion bolts are tightened.

The movement is not excessive but I would like to eliminate it all together if possible. I can get the table to withing .002" quite readily but then lose it to about .007"-.008" as the trunnions are tightened. With a little fusing and two ot three attempts I get to within my self imposed limit of .005". I would just like to eliminate the extra "fuss".

Once aligned it pretty much remains so until I tinker and I tinker a lot.

[benush26]

Dusty,
I was wondering if you could use a crows foot with a (short extension if needed) on those two basically inaccessible bolts? A neighbor had a motorcycle with come head bolts which were nearly impossible to tighten let alone torque, but a factory rep told him to use a crows foot and that as long as it was 90 degrees (horizontally and vertically) to the bolt and wrench he would get reasonably accurate readings.

Just a thought.

Be well,
Ben

[JPG]

The post by algale got me thinking. Yes, Yes a very dangerous thing for me to do. Anyway... Is there a ShopSmith suggested torque setting for the bolts? If so, could you sneak up on all four bolts in a cross pattern little by little until you reach that number? Tedious, probably, but also I would presume very little chance of changing the initial alignment and even if you did, a chance to correct it before the error grows too large.

Just a thought

Be well,
Ben

The key attribute of 'sneaking' up on the final torque is that the four bolts(screws actually) will not be exerting substantial forces before the other three screws are gradually tightened as well and they in turn will resist later forces as the screws are increasingly torqued.

I know, a but confusing!


About the crowsfoot wrench methinks the added 'lever arm' created by the crowsfoot wrench will 'slightly' increase the resultant torque applied to the screw/nut.

Would be interesting to check this with two torque wrenches and a crowsfoot/nut/screw.

[dusty]

I appreciate the ideas and comments and I will keep trying each until either it works or it does not.

I may need to quite posting about it though. I have received some PMs indicating that the audience is not keenly interested. My gig, so to speak.

The last table that I aligned was done by loosening only two "bolts" while leaving the other two tighter than I normally would but loose enough that a little force would move the table.

Side note:

Capture Bolt or Screw.JPG (45.31 KiB) Viewed 7025 times

[JPG]

An excellent example of common lack of concise use of terminology regarding the distinction between a 'screw' and a 'bolt' when referring to threaded fasteners.

The essential distinguishing attribute is whether the 'headed' end has a precision surface that bears against the object being secured and whether there is a surface(s) for a tool to apply torque for fastening/tightening.(slot/socket/hex...)

Thus there are carriage bolts. No surface for a tool.

There are structural bolts. Non precision bearing surface.

Pretty much everything else is a screw.

A screw can be a machine screw or a wood screw.

Damn Mickyd! He exposed me to the truth re screws/bolts.


And yes the world is full of examples of manufacturers mis-identifying them(especially from 'over there').

[JPG]

BTW Re: those PM telling you they ain't 'interested'.

Their loss!

JMHO


P.S. Your gig, so post whatever. 'They' can simply ignore.

[jsburger]

The post by algale got me thinking. Yes, Yes a very dangerous thing for me to do. Anyway... Is there a ShopSmith suggested torque setting for the bolts? If so, could you sneak up on all four bolts in a cross pattern little by little until you reach that number? Tedious, probably, but also I would presume very little chance of changing the initial alignment and even if you did, a chance to correct it before the error grows too large.

Just a thought

Be well,
Ben

The key attribute of 'sneaking' up on the final torque is that the four bolts(screws actually) will not be exerting substantial forces before the other three screws are gradually tightened as well and they in turn will resist later forces as the screws are increasingly torqued.

I know, a but confusing!


About the crowsfoot wrench methinks the added 'lever arm' created by the crowsfoot wrench will 'slightly' increase the resultant torque applied to the screw/nut.

Would be interesting to check this with two torque wrenches and a crowsfoot/nut/screw.

Yes it does. There is a formula for calculating that. The AF Technical Order on torquing has the formulas for determining the actual torque applied when you add different extensions to a torque wrench. In the aircraft world more fasteners are torqued than not. The tech order is very specific on how torque wrenches are to be use, cared for, calibrated, etc..

[jsburger]

BTW Re: those PM telling you they ain't 'interested'.

Their loss!

JMHO


P.S. Your gig, so post whatever. 'They' can simply ignore.

I absolutely agree. I really love these discussions and the ideas they produce. Sometimes we don't agree but that is OK.

I have said this before, KEEP IT UP DUSTY, and ignore the naysayers!!!!

[Gene Howe]

I'm interested!
Could you use a Master Plate or similar and clamp the table to it, then tighten the bolts? That assume the table's edge is true, I guess.

[dusty]

An excellent example of common lack of concise use of terminology regarding the distinction between a 'screw' and a 'bolt' when referring to threaded fasteners.

The essential distinguishing attribute is whether the 'headed' end has a precision surface that bears against the object being secured and whether there is a surface(s) for a tool to apply torque for fastening/tightening.(slot/socket/hex...)

Thus there are carriage bolts. No surface for a tool.

There are structural bolts. Non precision bearing surface.

Pretty much everything else is a screw.

A screw can be a machine screw or a wood screw.

Damn Mickyd! He exposed me to the truth re screws/bolts.


And yes the world is full of examples of manufacturers mis-identifying them(especially from 'over there').

I just recently ordered and received two sets of trunnion bolts from Shopsmith. See online catalog re: Shopsmith Part Number 426370