Metric to SAE...

I've searched, and searched, and searched... and cant find anything that gives anything relative to an answer to my question. Basically; I would just go ahead and give it a try (scrap material first of course), but I dont have access to the tools just yet...

Im trying to find out if re tapping a M6x1.00 to a 5/16-18 is doable. The wiggle room is there, but is it enough to create decent threads? Its not a critical part; just plastics stuff. But heli-coil is not an option, and i would rather NOT have to go bigger then 5/16... but will do what I gotta do to keep myself happy...

First question is why? It probably could be done but youre going to be looking at poor fitment quality compared to stock

I would take a wild swinging guess that something is stripped.

I think that should work fine. The F size drill bit used to drill the starter hole for the 5/16 x 18 should completely obliterate the 6mm threads for a fresh hole.

Agree w/ TR42. 5/16 is almost M8, so if you wanted to stay metric (having one SAE head in a metric assembly might be an asspain) you could consider that.

Oops.... I was meaning M8 not M6. My bad. The M6 I want to tap out to 1/4-20's. But Im trying to go from M8-5/16. And the reason why? Because i want to! :thumbsup: Nah, I did strip out a hole, and helicoils are NOT an option (thin sheet metal body tab).

But dont want to keep metric... because im picky. But yea, I uhh... wasnt thinking, and its actually going from M8 to 5/16... Its like a M12 and 1/2 - Cept its so close on fine thread of those; they can damn near tap eachother...

you could do it but the threads wont be nearly as strong, you will be taking away from the current threads instead of cutting new ones from a simple hole.so doing it is really not a good idea.

if your going through thin sheetmetal though your cant really cut threads not enough metal for it, so maybe a good question is how thin of sheetmetal is it.

you could do it but the threads wont be nearly as strong, you will be taking away from the current threads instead of cutting new ones from a simple hole.so doing it is really not a good idea.

if your going through thin sheetmetal though your cant really cut threads not enough metal for it, so maybe a good question is how thin of sheetmetal is it.

Its my rear fender bolt tab thing... prolly 1/4 inch thick. Enough to tap, not enough to heli-coil. So i dont need STRONG threads; just strong enough to hold the plastics on. But... i may just bite down and enlarge them to 3/8... even tho thats like stupid big; if i remember correctly; its a pretty large hole thats stripped out tho...

Thanks...

Do you have room to tack-weld a nut on the back side, or simply fill the hole with a bead of weld and re-drill and tap it?

Its my rear fender bolt tab thing... prolly 1/4 inch thick. Enough to tap, not enough to heli-coil. So i dont need STRONG threads; just strong enough to hold the plastics on. But... i may just bite down and enlarge them to 3/8... even tho thats like stupid big; if i remember correctly; its a pretty large hole thats stripped out tho...

Thanks...

You beat me to it...that's what I was going to say!

I'd shoot for something with a few more threads in there, like this:

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You know what they say......."Great minds think alike".

You beat me to it...that's what I was going to say!

Lol, neg on the welder (unless you wann come do it :thumbsup: ) Never welded, dont have one. But I didnt think about the u nut things. Only downside is im picky. oh well, we'll see what im more picky about... thanks guys!

One more suggestion. If you really can't repair the threads reliably why not just drill it clean and put a longer bolt through the hole and thread a locknut on it.

I've searched, and searched, and searched... and cant find anything that gives anything relative to an answer to my question. Basically; I would just go ahead and give it a try (scrap material first of course), but I dont have access to the tools just yet...

Im trying to find out if re tapping a M6x1.00 to a 5/16-18 is doable. The wiggle room is there, but is it enough to create decent threads? Its not a critical part; just plastics stuff. But heli-coil is not an option, and i would rather NOT have to go bigger then 5/16... but will do what I gotta do to keep myself happy...

Like you said here and in another post it's not a critical area. What about drilling/tapping to the size you were thinking (5/16--1/4-20) and use a NyLock bolt? The dab of nylon may help hold the bolt tighter without having to re-engineer this thing!

so i meant to ask this earlier but what kind of picky has to do with having SAE vs Metric?

theres no strength difference in the 2

so i meant to ask this earlier but what kind of picky has to do with having SAE vs Metric?

theres no strength difference in the 2

Im so gonna get flamed for this... None of it is strength, is all cosmetic. Im doing a Grey/Green/Black scheme on my bike, and wanted Gold Grade 8 Hardware... the equivalent in Metric (class 10.9) does not come gold. And, no matter what i do to this one; i have to do to all screw holes a like, due to my OCD of being all the same and such.

Im so gonna get flamed for this... None of it is strength, is all cosmetic. Im doing a Grey/Green/Black scheme on my bike, and wanted Gold Grade 8 Hardware... the equivalent in Metric (class 10.9) does not come gold. And, no matter what i do to this one; i have to do to all screw holes a like, due to my OCD of being all the same and such.

Are you sure you can't get them in "gold"? Where have you looked? There are several companies that supply mfg companies with "colored" hardware like cadmium, or zinc coating...

Mcfadden-Dales is one...been out of the biz for a while I can't remember the others at this time.

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