Technical Adjustable reamers (were not the answer to my problem)

This was my first thought, but since this is not the first time I've had similar problems, and since this is not a pressing project, I thought I'd cast around to see if there was some "magical" bit I could put in my battery powered drill that would clean up these very minor imperfections. For now, I'm going to take "DDDENNY"'s advice and try to find "a ball nose burr, 3/8" dia. with the standard 1/4" shank" at a reasonable price for a start.

 

Use a 3/8 mill cutter. It will cut on the ends as it goes through. I use them after taking frame rivets out ,never had one grab. Use it in your cordless drill.

 

Now ya' tell me. It's half the price of the $10 ball nose burr I just ordered! I look at it this way : I already saved $10 by getting the ball end burr rather than the adjustable reamer I was originally considering. If it works, fine, if not, I'll order the $5 mill cutter and I'll have $5 left over. It's a win-win.

 

5/16" bolts should be more than adequate for a collector flange.

 

I can't believe we got two such responses; one, yeah OK, but TWO?

 

Well, I guess I should be the last one to call someone out on something like this. The reason my "downpipe" flange holes are too small is because the bolts that came with the headers are 10mm which are about .040 bigger diameter than 3/8". The bolts to attach it to the engine were the proper 3/8" header bolts. They sent 16 of those and NO 7/16 bolts (this is a flathead, remember). I just ASS U ME d that they were standard 3/8" bolts. Part of what fooled me was that the nice flange nuts they sent with it fit a 9/16" wrench perfectly, even thought they were 10mm. The heads of the bolts were bigger, though. A trip to the hardware store for the proper 3/8" nuts and bolts solved all of my problems (with this, anyway).

This is the first time I've been bit by the "foreign fastener bug". You can bet that next time I'll check 'em at the beginning of the project, not the end. How can they be smart enough to drill the flange holes 3/8" but dumb enough to send 10mm fasteners?

 

Oh Man, do I feel your pain. Went through that on a new Edelbrock intake. All 4 of the Carb studs were metric. Holes were tapped right. Nuts for the studs were metric also, could have been a real issue. Geezzz!
The Wizzard

 

I'm sure many here have experienced this, I have (more than once) and I made a pact with myself, when a metric fastener lands on my bench; unless it was invited it goes directly in the trash can. I chased my tail as the OP did because I just couldn't throw away those shiny new nuts and bolts and they ended up in one of my fastener organizers, never again.
On the VERY odd occasion that I may require a metric fastener the local hardware store is only minutes away.

 

Just to clarify, are you saying Edelbrock supplied metric carb studs and nuts, or were they purchased separately?

 

I keep a small stock of metric, but I do have metric projects. I also use them as theft deterrents occasionally on the old US-built stuff for easily-removable bits.

The problem is the 'bastard' hardware the clever Chinese sometimes supplies. Standard heads/nuts with metric diameters/threads could be a disaster if you get caught not paying attention. I buy a fair amount of imported stuff (who doesn't...), but ya gotta watch 'em....

 

Can you lay a gasket over the ports and use a permanent marker to locate where holes should be? I've a large compressor and a pneumatic die grinder that I use all the time with different high speed burrs. Also make sure you don't buy aluminum burrs, get the steel ones. Since my recent surgery to rectify carpal tunnel and a pinched ulna nerve I can empathise with your condition and feel your pain.

 

I keep a few bins of metric crap, because I end up needing it occasionally (unfortunately I live in the real world). But they stay separate from real hardware.

Glad you figured out the real problem.

 

Just buy a Oregon chain saw file. they are great at sharpening the extremely hardened Oregon chain saw teeth. And will quickly remove enough metal to enlarge those header flange holes.

 

Really?
Just buy metric fasteners and done not a big deal.

3/8 and 10 mm are almost the same ( a striped 10mm will come off with a 3/8 socket
7/16 and 11mm are the same

1/2 and 13mm are the same

9/16 and 14 mm are the same

11/16 and 17 mm are the same

3/4 and 19mm are the same

And in metric when they talk about size 10mm X1.25 they are not talking about head diameter but thread size

Say what you want metric sizing makes way more sense then impiral and it’s only “ yoos guy Liberia and Myanmar “ quite the power houses of countries

 

Borrow a cordless drill with a clutch on it, turn the clutch down to halfway, put the proper sized drill bit in the chuck, and make your holes the proper size. Why go through all the extra trouble and expense....?

 

Can't take the easy way out and use smaller bolts ?

 

3/8" = .375"
10mm = .3937"
1/2" = .500"
13mm = .511"
9/16" = .5625"
14mm = .551"
11/16" = .6875"
17mm = .669"
3/4" = .750"
19mm = .748"

 

Have any of you read the whole thread? It sure doesn't seem like it.

 

Maybe you should kill this thread before the 4 above hurt themselves.

 

Gladly; how do I do that?

 

I know I've done it. Somewhere in the first post maybe. Or just ask Ryan.

 

I also have a couple of 1/4 inch shaft carbide burrs, of various shapes, that I use for jobs like this. Even a high speed steel burr would work well because the lower speed of the drill is not likely to overheat the bit.
I have also used a 1/64 or 1/32 inch larger bit and drilled a larger hole. Just lubricate the hole before you drill it. If you are worried about the bit grabbing, you could attach (even duct tape) a bar onto the drill handle to give you more mechanical advantage.
Bob