Stripped Bolt?

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Duncan
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Stripped Bolt?

Post by Duncan »

There's a fellow Paceship owner having a hard time getting a bolt out over here - anybody seen anything like this, got any ideas?
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bcooke
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Post by bcooke »

No good news from me I am afraid. The point where a little finesse might have done the trick is past. It sounds like something has deformed inside the mast which is holding the bolt. Aluminum is softer than steel and when the hammer struck it was probably the softer material that deformed first.

I would grind the bolt ends smooth with the mast and drill into the bolts. With some luck, as soon as you have drilled down the thickness of the mast wall whatever is holding the bolt will be released and the bolt will come out or at least the fitting will come out so that you can attack the bolt from a better position. To drill stainless, turn the bit slowly, use a lot of pressure, and use lots of cutting oil. If the bit starts to smoke, STOP! because the bit is a second away from losing its heat treating and turning into mush. You should see steady curls of material if every thing is going right. I should add that I rarely get it to go that good. Have extra bits handy.

Failing that, identify whatever part is cheapest to repair, replace or fabricate and simply destroy it to get the bolt out. That would be either the fitting or the lower section of the mast.

Note 1: always think twice before swinging the hammer.
Note 2: always protect the threads of the bolt. Usually by threading the nut loosely in place.
Note 3: Think again before picking up that hammer.
Note 4: NEVER let a buddy help you out when he/she has a hammer in hand.

An experienced well struck hammer blow (plus a little luck) can do wonders. It can also make the project significantly more complicated. Trust me, I live a complicated life...

-Britton
Duncan
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Post by Duncan »

Thanks, Britton, especially for the step-by-step on drilling out, which it may well come down to. I certainly agree about the hammer - high risk, high reward! Too bad the other guy didn't just double-nut the bolt, instead of mangling the exposed threads with the visegrips (i.e. your Note #2).

After thinking about it and asking around a bit, I'm inclined to the theory that there's an aluminum sleeve inside. The fact that it turns freely, but won't come out, suggests the steel bolt has corroded to the aluminum sleeve, and the two are turning together?

In this case, it sounds like trying to get some penetrating oil in there would be a good start ("first, do no harm"). Trying to get a nut back on, putting a backing plate on the other side of the mast (with a hole for the bolt head), and then applying force to the nut seems like the best bet so far.

I'd be inclined to see if the bolt would thread out under pressure (i.e. it's stripped or jammed, but may cut its way out). If it still just spins, then whacking the sucker with a sledge starts to sound more realistic, so long as it's done with great determination and precision.

As you say, after that, it's down to drilling, or destruction.
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Ceasar Choppy
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Post by Ceasar Choppy »

I've had very good results with Kano Kroil penetrating oil and a little heat. Kroil isn't always easy to find except if you frequent gun shops. A gun enthusiast turned me on to it which is how I found it.
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Post by Tim »

Most through-spar bolts like that should have an internal spacer (sleeve) to prevent the bolt from compressing the spar when tightened. It's almost certainly that sleeve, which is probably made from aluminum, which is preventing the bolt from coming out.

Another option might be to use a hole saw just bigger than the bolt head to cut out the spar in that area, which would then allow the bolt and sleeve to come out easily (assuming that is actually the issue at hand).
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Post by Tim »

These are the pictures from the other forum that show the assembly in question.

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Duncan
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Post by Duncan »

Thanks very much, gents - the sleeve theory is well-supported by someone reporting the same thing on a Pearson 10M at the spreaders.
The super penetrating oil sounds good, and using a hole saw certainly sounds much more elegant and precise than some of the alternatives!
I'll link this topic so Peter can get to it from the Paceship forum. Much obliged!
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bcooke
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Post by bcooke »

Kroil, PB Blaster, and a few other penetrating oils have a pretty good reputation. Whether they can break the bond between the spacer and the bolt is probably a 50/50 proposition but it is certainly worth a try. It would take a lot of corrosion to stand up to the hammer blows so that is why I am not more positive.

I had never thought of using a hole saw on aluminum but I guess it would work. As a general rule there are better ways of cutting holes in aluminum but in this application I think it would be the right way to go. You will still have to think about patching the hole when you are done unless you want to replace the bolt with a much oversized one.

As for getting the nut back on, you can buy files with teeth that fit the threads on bolts (called thread files not coincidently). If the threads are not too bad (they don't look too bad in the photo) this would be a good way to recover the threads. Failing that you could get a thread die and cut new threads. The problem with that is that the new threads probably won't align with the old threads but I suspect the bolt will be replaced after it is removed so that might be an option. You might even find a 'thread restorer' which straightens out mangled threads without cutting new metal.

Just some thoughts. With a little luck, a little juice and a little iron persuasion the bolt will hopefully decide to come out with little fuss.

-Britton
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Post by martin »

If you decide to go whacking the threaded end be sure to support the aluminum around the headed end. By support I mean something hard like steel, wood will not be hard enough and will allow the mast to deform. You are probably correct thinking there is a sleeve in there to stop from crushing the mast. Aluminum and stainless have a less than happy relationship on a good day. If you can warm up the bolt head before you pour some penetrant on the threaded end, as it cools it will pull the penetrant in to the threads where most of the white powdery looking stuff will be. That stuff is very abraisive and is what is holding things from moving. Once its wet it should move fine. If you can actually submerge the end on the mast in kerosene to the point the bolt is covered for a couple of days it should be a breeze to knock it out. Kerosene is one of the best penetrants around. Good luck and go slowly.......martin
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Post by Duncan »

From another PY23 owner:
I have had mine apart. I agree that the sleve that the bolt passes through have seized together. soak it with a lub oil and use a larger hammer. If that doesn't work grinding off the head so the sleve can come out with the bolt should do the trick.
And from Peter:
Thank you all. I couldn't imagine why the bolt wouldn't come out. It all makes sense now.

It looks like I will cut the bolt head off. That sounds like the most likely way to avoid damage to the aluminum mast. I'm afraid a bigger hammer could tear a bigger hole at the bolt head end if the cylinder didn't separate from the bolt.
Thanks for the assistance, one and all.
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Figment
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Post by Figment »

huh?

how does cutting off the bolt head help the problem of the siezed sleeve?
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don't know

Post by kendall »

how it will help there, but often if you cut the bolt head off, then use a C-clamp with a tight fitting socket over the threaded end, maybe a smaller socket on the other end to push on the bolt you can push the bolt out of the sleeve with little effort, use a GOOD C-clamp though, the chinese products twist around on you.

ken
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Post by Duncan »

Figment wrote:how does cutting off the bolt head help the problem of the siezed sleeve?
There's an aluminum "compression tube" or bushing that is slid in from the nut-end of the mast hole. The hole on the bolt head end is smaller and the bushing snugs up against the interior of the mast, sitting flush with the exterior of the mast at the nut end. The only way to get it out is grind off the bolt head.
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