Spiderplate error (booboo when drilling)

[oddname]

Well I drilled the wrong marking, middle ones on both side :)

My question is, what is the best way to deal with it, plugweld them or relocate as marked on the tape the picture in the link below. Moved them about 1,5cm each. Does the slight decrease in distance between them make it worse?


http://pici.se/p/large/yQgwXizRk/


Added a before and after pic on the bearings are supposed to be placed and how they will be placed if positioned like the tape is marked.

Before
http://pici.se/p/large/SBFJHFBZY/


After
http://pici.se/p/large/NnqIfnAkC/

[MetalHead]

I would plugweld and redrill myself. But I'd wait to see what others say. Relocating the wheels will mess up the spider movement.

[oddname]

In which way will it mess up the movement? It's still linear
Or do you mean it will be... "wobbly"?

[MetalHead]

The length of travel up and down on the spider is supported by the bearings. The motor and gear are moving the axis, but the v-rollers are holding the plate in position and the rollers control the ability to raise and lower the plate to a certain position as seen here.

http://www.mechmate.com/forums/showthread.php?p=13441&postcount=66

[swatkins]

While getting ready to drill my plate I though about this problem quite a bit... I didn't make the mistake so everything worked out fine for me but maybe my solution would work for you...

Because you are welding the stand-off on one side of the plate and the nut on the other you are effectively securing the bolt at both sides of the plate and the hole is really only there for initial alignment. Once the welding is performed the bolt location is fixed..

IF I had made the mistake I was going to slot the holes so that I could slide the bolt side ways, to the correct location ,tighten them and proceed with the welding... The bolt would have been supported by three sides of the hole and fixed in place with the welding of the nut and stand-off.

[Gerald D]

Frallan, the best is to weld the holes and drill again.

[oddname]

I just dropped my piece of at my local company helping me, they claim its a bad idea to work a welded area since its hardened where the weld is, but I will try.

[jeffa]

frallan,

Erick and I made exactly the same "booboo" as you did on our spider. We just welded up the the mis-drilled and tapped holes, ground down our welds and then re-drilled. No problems. The spider is mild steel and so was our welding wire, so no hard spots to worry about. Hope this helps,

Jeff

[oddname]

Hopefully itll work then :)

They just said it could be that the steel hardened due to the heat.
Just picked up the fixed part and it looks nice so a 2nd attempt later today/tomorrow.
Im going to start from the outer markings, any idea on how much to put on extra to get some room för adjustment?

[Gerald D]

Frallan, why did you not see the following thread before you drilled: ;)

Spider Plate Oh-Oh!! (which # mark to drill on?) (http://www.mechmate.com/forums/showthread.php?t=1611)

[oddname]

Well I made a mistake when measuring, forgot to add the depths of the groove on the bearing and then it want as it went :P

At least I got a fresh start now and got my nice rails too finally!
http://pici.se/gal/oddname/MM%20skenor/ Just need to brag a little :P

[domino11]

Nice Rails! :)

[oddname]

Thanks :P (not my work though)

Was measuring and calculating, i will need 138.1mm center to center for the bearing, but it seems stupid to make it that, so what is ok to use to allow some adjustment?
Using the "kit" from superiorbearings. 142mm too much in totalt för adjustment? or how much "play" does the bushing allow?

[Gerald D]

Stick with the plans, they are not "stupid" ;). 138mm is the right measurement for you. 142 will be too much and you will be welding and drilling again. :(

[oddname]

Roger, will be making someone else drill and tap for me this time :P
So 138mm is actually the right measurement on the part itself? (outer markings) made them go away when getting the weld done so using some old reference points