Broken bolt = square paperweight

[Rusty Nail]

Yeah..

Soooooooo

Ummmmmmmmmm



what kind of manifold didjya find old boy?
Got anything cool?

Here's a brand new / never installed Holley 300-28Z (701r-28z)

You must be registered for see images attach

That's pretty cool. Great truck manifold.

https://books.google.com/books?id=LdkDAAAAMBAJ&pg=PA69&lpg=PA69&dq=Holley+300-28Z&source=bl&ots=BvLf4jGF8X&sig=WA0KaXM2rUQBo1EDm4TD5Pxv5bE&hl=en&sa=X&ved=0ahUKEwi7063oiYDUAhUp3IMKHVXcAi0Q6AEITjAG#v=onepage&q=Holley 300-28Z&f=false

 

[jake wells]

think i will stick to my stock iron manifold.

 

[RecklessWOT]

And cutting oil. Cools the drill bit.



Depends on what you are drilling, but here are ballpark numbers: 1/4" bit in cold steel, 500 RPM with coolant. Carbide drill bit, slower. Hardened bolt, little slower again. Jump in size to 1" drill bit, 40-60 RPM.*

Remember, the hardened bolt is only surface hardened. Start with a smaller pilot drill bit, the center of the bolt is softer. Then drill with the tap drill bit size.

* A machinist handbook can be very helpful

actually, recommended spindle speeds are 3x that of the speed of regular HSS drills or mills. And feed rate is about 1.5-2x depending on material. They're more brittle and less tolerable of abuse, but by design they can withstand higher speeds and feeds so higher speeds and feeds are not "abusive". if you go too slow they will actually chip out easier because they overheat. Even with flood coolant they can work harden the part which increases tool wear and will cause them to fail prematurely. And when carbide fails watch out, sometimes there's shrapnel. And if not there's at least carbide embedded in your workpiece, hopefully you can dig it out because any drill/mill you send in after that without completely removing it all is ****** too.

 

[Vbb199]

actually, recommended spindle speeds are 3x that of the speed of regular HSS drills or mills. And feed rate is about 1.5-2x depending on material. They're more brittle and less tolerable of abuse, but by design they can withstand higher speeds and feeds so higher speeds and feeds are not "abusive". if you go too slow they will actually chip out easier because they overheat. Even with flood coolant they can work harden the part which increases tool wear and will cause them to fail prematurely. And when carbide fails watch out, sometimes there's shrapnel. And if not there's at least carbide embedded in your workpiece, hopefully you can dig it out because any drill/mill you send in after that without completely removing it all is ****** too.

I'd run a 1/4 HSS drill in annealed toolsteel at 840 rpm, 4.2 feed.

Regular old low carbon steel, 1146 rpm, 5.7 ipm

 

[Shorty81]

Back in the old days I would use a 50/50 mix of never seize and moly grease on the steel bolts into the aluminum swing arms on our mx bikes to combat the chemical reaction. It worked great.

 

[Buickspec6231]

You can try to use I believe it's sulfuric acid and something mixed to dissolve the steel bolt. Allegedly it doesn't harm the aluminum. I tried to find the video where aVe demonstrates it on YouTube, but I didn't have any luck finding it. I remember him doing something like an exhaust manifold bolt that way. You can Google search it and see other examples of other amateur chemists doing the same.

 

[RecklessWOT]

I'd run a 1/4 HSS drill in annealed toolsteel at 840 rpm, 4.2 feed.

Regular old low carbon steel, 1146 rpm, 5.7 ipm

There's the whole school of thought that says cut your speed in half for drilling but I usually do about 80% and come out fine on the other end. IMO that's mostly for dudes on bridgeports with ****** cooling, etc. For regular carbon steel I'd probably be around 750-800 at about F3.2 maybe a tad more. That's for something like SA105 carbon. Most of the stuff we deal with is 300 series stainless or more, 316 is baseline the softest stuff we deal with (the occasional 304 is a treat), it's usually 316L/H, 321, or c276 hastelloy or nasty 800/825 inconnel ****. For the 316 I'd be about 600rpm at about 1.5-2ipm, peck drilling with lots of coolant of course. It really varies on material, how deep I'm going, if the hole is getting threaded after, how the part is being used, etc. The vast majority of stuff I make is for fuel refineries or other similarly corrosive high heat/pressure environments like power plants, etc.

 

[Vbb199]

There's the whole school of thought that says cut your speed in half for drilling but I usually do about 80% and come out fine on the other end. IMO that's mostly for dudes on bridgeports with ****** cooling, etc. For regular carbon steel I'd probably be around 750-800 at about F3.2 maybe a tad more. That's for something like SA105 carbon. Most of the stuff we deal with is 300 series stainless or more, 316 is baseline the softest stuff we deal with (the occasional 304 is a treat), it's usually 316L/H, 321, or c276 hastelloy or nasty 800/825 inconnel ****. For the 316 I'd be about 600rpm at about 1.5-2ipm, peck drilling with lots of coolant of course. It really varies on material, how deep I'm going, if the hole is getting threaded after, how the part is being used, etc. The vast majority of stuff I make is for fuel refineries or other similarly corrosive high heat/pressure environments like power plants, etc.

The only stainless I like is 400 series! Lol
**** the 3xx series!!!!

 

[RecklessWOT]

The only stainless I like is 400 series! Lol
**** the 3xx series!!!!

Yuck. I just had to deal with a bunch of 422 today. Bunch of nappy **** that leaves a poopy surface finish finish and makes a mess in the machine. Not to mention it clogs up the chip conveyors on the lathes (for however infrequently I run those). Might as well be carbon but you also gotta go slow. No fun no matter how you look at it.

When I started working where I am now it took me a little while to get used to the hard stuff, but now I actually prefer the 300 series. Something about making mirror surface finishes tickles me in just the right way lol

 

[gotyourgoat]

Haven't gotten it out but haven't made it any worse either. It sits as it was apart from some penetrating oil on the infected area.

For good or bad I don't have a welder or any easy outs. The manifold and bolts are from the previous owner. It has been regasketed already because the gobs of blue rtv they used were not sealing. The idea and all the work of pulling this intake again and putting a new one onto this oil burning son of a bitch was not the next step in the upgrade plans.

Thanks for the ideas and I do appreciate any and all thoughts on the subject. Just sort of in limbo weighing methods, parts costs and time/work to unbrick ol brown. Most routes at the moment aren't giving me that warm fuzzy feeling.

 

[wanderinthru]

Haven't gotten it out but haven't made it any worse either. It sits as it was apart from some penetrating oil on the infected area.

For good or bad I don't have a welder or any easy outs. The manifold and bolts are from the previous owner. It has been regasketed already because the gobs of blue rtv they used were not sealing. The idea and all the work of pulling this intake again and putting a new one onto this oil burning son of a bitch was not the next step in the upgrade plans.

Thanks for the ideas and I do appreciate any and all thoughts on the subject. Just sort of in limbo weighing methods, parts costs and time/work to unbrick ol brown. Most routes at the moment aren't giving me that warm fuzzy feeling.

Being a steel bolt in an aluminum manifold, that broke off instead of breaking loose, I personally would figure on a 0% chance of ever screwing it out. It will need to be re tapped at best, more than likely require a helicoil or insert. My guess is it was put in to tight and the alum threads are pulled a tick. You don't have anything to loose by drilling it out, get so far off that it cant be helicoiled or inserted (Can ream the holes in the cap/nipple if need be) the intake will be useless.....which is what it is now. Good luck!!

 

[Ricko1966]

Haven't gotten it out but haven't made it any worse either. It sits as it was apart from some penetrating oil on the infected area.

For good or bad I don't have a welder or any easy outs. The manifold and bolts are from the previous owner. It has been regasketed already because the gobs of blue rtv they used were not sealing. The idea and all the work of pulling this intake again and putting a new one onto this oil burning son of a bitch was not the next step in the upgrade plans.

Thanks for the ideas and I do appreciate any and all thoughts on the subject. Just sort of in limbo weighing methods, parts costs and time/work to unbrick ol brown. Most routes at the moment aren't giving me that warm fuzzy feeling.

Seriously do not even try an EZ out,drill and tap it since you don't have a welder. When I worked at the machine shop we'd have 1 customer A week come in with an EZ out broke off in it, and not understand why it cost more to fix han if he hadn't messed with it. You have to drill a hole for an EZ out anyway so drill the hole than drill it bigger, than bigger than you can collapse the hollow bolt, if you can do that the hole will still be right.Push comes to shove you can still tap it.Even if your drilled hole and tapped hole is off a little, you can fix that.

 

[rt66paul]

Working around steam and hot piping in my early years taught me that graphite grease is a good thing. Never seize, copper coat, even lead coat are great dressings to keep bolts from galling and coating gaskets means they come off when you need them to.

 

[jjester6000]

I remember trying to replace my thermostat once (preventative maintenance) and I broke off one of the bolts. Then I decided "Nah, thermostats fine, I don't need to replace it." 2 years later it never leaked, and I replaced the whole engine.

 

[Craig Nedrow]

As a machinist, I have a system that works, literally have removed thousands of broken bolts. If that is a 3/8-16 bolt, the tap drill is 5/16 for 75% thread. If you have a drill press, and can secure the intake so it is steady, here's how I do it.
1) use a #3 centerdrill, line up on the center of the broken bolt. This is an eyeball thing. Use a little black oil, or some type of lube, this is probably a grade three bolt so not to hard so run around 1000 RPM conservative speed. formula is 4 X cutting speed divided by tool dia. = 1600 as #3 c-drill is .125. Cutting speed for 1018 is approx 100 SFPS, alum 4 times that, alloy steels approx 4 times divided, gets you in the ball park. Drill the hole with the center drill until you get close to the diameter, clear chips. If you notice that you are not quite on center use a smaller drill then 5/16. Drill out the rest of the bolt, use a pick on what is left, and carefully run a tap into the original hole clearing often as you break the chips. Here are some pics:

Various center drill sizes
intake on drill press with 5/16 drill
gun tap 3/8-16
easy out if you drill an under size hole. If you use the easy our method, beat on the bolt with a flat punch, and use heat, helps break the bond.
The oil I use, can't beat sulfur based oil, Aerospace, and nuclear, it is often not legal to use. Hope this helps. Would do it for you if you were close.

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach