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babelloyd
04-30-2010, 01:06 AM
Hi folks!

The beginning of page 113 (in the Kyoto Cruiser plans) says "After a little grinding and filling...". Does this mean filling the holes in the curved wall of the bottom bracket tube? Figure 99 shows a bottom bracket with mounting plates installed that has a hole in it.

I'm a bit confused.

Thanks for your time!

Dave

savarin
04-30-2010, 02:58 AM
I believe its worth filling in the holes to keep out the crap.
If you have a good feel for the molten puddle it can be done in one go.
Untill you get the confidence for this I would suggest weld around the hole in one pass, allow to cool a bit, then another go round what hopefully is a smaller hole, cool a bit and so forth.
You may have to refill bits once you grind back to smooth but that not a big deal.
Good luck.

schu777
04-30-2010, 09:14 AM
.... I would suggest weld around the hole in one pass, allow to cool a bit, then another go round what hopefully is a smaller hole, cool a bit and so forth.

Yep - I've been practicing my welding on the remains of a donor bike. I've been blowing holes here and there, but the filling does work just going around the hole, let cool, then do it again until it is filled. My only problem is that it gets to be kind of high - so maybe doing some grinding as one goes - I guess it depends on how BIG the hole is...I've had some big ones :rolleyes4:

Michael

Big Moe
04-30-2010, 09:50 AM
A realwelder friend I once knew would pick out a washer which fit the hole he wanted to fill and tack it in, leaving a much smaller hole to weld fill. MOE

savarin
04-30-2010, 10:38 AM
I fill all my holes vertically down with gas shield mig. Not a problem.
The washer idea also works very well but I'm too lazy to get one, curve it, tack it then weld.:rolleyes4:

babelloyd
04-30-2010, 12:05 PM
Does it matter if I get molten metal inside the bottom bracket? Is the bottom bracket useless if I burn a hole through it?

jimFPU
04-30-2010, 12:30 PM
To some degree it matters. Try not to get spatter on the threads, or you will have to take it to the LBS to get cleaned up, unless you have a BB threader.use foil or copper to help protect them.

babelloyd
04-30-2010, 12:42 PM
Right, good point. Sadly, I don't know what the LBS is. Or how I'd use foil or copper. Would I press foil into the thread all around the inside of the bottom bracket on both ends?

64c10
04-30-2010, 02:17 PM
Right, good point. Sadly, I don't know what the LBS is. Or how I'd use foil or copper. Would I press foil into the thread all around the inside of the bottom bracket on both ends?

Local Bike Shop, yes with foil , you want to cover the threads so you dont get the small weld spatter stuck to them

vrooom3440
04-30-2010, 03:38 PM
Actually from what I have read... the best bet is to keep the bearing races screwed in when welding the BB shell. That prevents any splatter issues AND helps keep warpage from becoming a problem.

That is how I would take care of that problem anyways.

babelloyd
04-30-2010, 03:55 PM
Great tips! Thanks so much!

schu777
05-01-2010, 07:36 AM
Actually from what I have read... the best bet is to keep the bearing races screwed in when welding the BB shell.

As long as they are metal...not plastic - I had put in a new bottom bracket on my road bike - self contained and it had an outside plastic on one side, so I don't know if that would be true with the types of bikes we use in Zombie land.