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When checking camshaft runout, is it acurate enough to use a set of home made wood V-blocks?

A while back, i made a set of v-blocks for checking crankshaft run out and it works prety good and i have bouble checked it with checking the crank in a block, sitting on the two end bearings and get the same readings, but a crankshaft is heavy!

A couple of weeks ago, i was curious and wanted to check the cam run out. i set the cam up in the vblocks and set the dial indicator on the center cam journal. Rotated the cam and the needle is back and forth all over the place!
I tried fitting the cam back in the bearings and it will only go in about half way and it actually will get stuck. I dont even know how the guy got the dam thing out!
To double check my vblock's, i have another cam that i set up and the dial indicator read less than .001 movement.
I guess I have prety much answered my own question, I am pretty sure the dam cam is bent!

I was just wondering if anyone has used wood vblock's, with success?
 

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When checking camshaft runout, is it acurate enough to use a set of home made wood V-blocks?

A while back, i made a set of v-blocks for checking crankshaft run out and it works prety good and i have bouble checked it with checking the crank in a block, sitting on the two end bearings and get the same readings, but a crankshaft is heavy!

A couple of weeks ago, i was curious and wanted to check the cam run out. i set the cam up in the vblocks and set the dial indicator on the center cam journal. Rotated the cam and the needle is back and forth all over the place!
I tried fitting the cam back in the bearings and it will only go in about half way and it actually will get stuck. I dont even know how the guy got the dam thing out!
To double check my vblock's, i have another cam that i set up and the dial indicator read less than .001 movement.
I guess I have prety much answered my own question, I am pretty sure the dam cam is bent!

I was just wondering if anyone has used wood vblock's, with success?
Chances are, when that thing came apart, the broken rod nailed the cam. Its not that unusal. If you can feel the cam stick, its bent.
Look for a spot around where the rod that broke would hit it, and see if there is any marks.



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When checking camshaft runout, is it acurate enough to use a set of home made wood V-blocks?

A while back, i made a set of v-blocks for checking crankshaft run out and it works prety good and i have bouble checked it with checking the crank in a block, sitting on the two end bearings and get the same readings, but a crankshaft is heavy!

A couple of weeks ago, i was curious and wanted to check the cam run out. i set the cam up in the vblocks and set the dial indicator on the center cam journal. Rotated the cam and the needle is back and forth all over the place!
I tried fitting the cam back in the bearings and it will only go in about half way and it actually will get stuck. I dont even know how the guy got the dam thing out!
To double check my vblock's, i have another cam that i set up and the dial indicator read less than .001 movement.
I guess I have prety much answered my own question, I am pretty sure the dam cam is bent!

I was just wondering if anyone has used wood vblock's, with success?
I would consider getting it to a cam grinder if the shop you are using can't help. If you can get it to me I can have it checked free, and if it can be straightened, he can do it
 

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Discussion Starter #4
Chances are, when that thing came apart, the broken rod nailed the cam. Its not that unusal. If you can feel the cam stick, its bent.
Look for a spot around where the rod that broke would hit it, and see if there is any marks.
Yes Bob, There is a very slight mark on one lobe.
 

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I have seen many cams straightened. The guy who does mine checks and straightens both prior to grinding and after it's ground. Pretty wild to watch him take a hammer and chisel to a cam in the fixture!
For me, it would totally depend on the camshaft, I would have to be stupid happy with it to go through the straightening process on a used cam that sustained damage during a rod throwing contest, one of those things that would always be in the back of my mind.

Probably just me though.
 

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For me, it would totally depend on the camshaft, I would have to be stupid happy with it to go through the straightening process on a used cam that sustained damage during a rod throwing contest, one of those things that would always be in the back of my mind.

Probably just me though.
I have been thru this twice with cams that were bent between journals, which all cams hit by a rod are. And neither time could they be straightened. They aren't bent or warped from heat treat, they are kinked. The distance between any two journals is so short that the bend is usually to severe in one spot to straighten successfully. Then add in that the cam is almost certainly damaged somewhere. The odds of hitting the cam with a rod and not hitting a lobe are somewhere between nil to zero. So now it needs to be reground. To what, the same profile? Some thing else. Straighten plus regrind? If it was some custom ground 60 MM deal I might consider it. But then, if it was a bent 60 MM, you know it had to take a wacking. Throw the POS in the round can next to the bench.



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For me, it would totally depend on the camshaft, I would have to be stupid happy with it to go through the straightening process on a used cam that sustained damage during a rod throwing contest, one of those things that would always be in the back of my mind.

Probably just me though.
I have been thru this twice with cams that were bent between journals, which all cams hit by a rod are. And neither time could they be straightened. They aren't bent or warped from heat treat, they are kinked. The distance between any two journals is so short that the bend is usually to severe in one spot to straighten successfully. Then add in that the cam is almost certainly damaged somewhere. The odds of hitting the cam with a rod and not hitting a lobe are somewhere between nil to zero. So now it needs to be reground. To what, the same profile? Some thing else. Straighten plus regrind? If it was some custom ground 60 MM deal I might consider it. But then, if it was a bent 60 MM, you know it had to take a wacking. Throw the POS in the round can next to the bench.
I offered to have it checked for free for him, can't beat that with a stick?

The ones I have seen straightened were not damaged by engine failures, just routinely checked before grinding.
 

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I offered to have it checked for free for him, can't beat that with a stick?

The ones I have seen straightened were not damaged by engine failures, just routinely checked before grinding.

Not saying anything negative your way Barry, just think that even if there was a question about the condition of a cam from an internal event, the cam would be wall art...

holorinhal has had enough dram IMHO.

Super cool of you to offer that up... First class bud. :thumb:
 

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I have seen many cams straightened. The guy who does mine checks and straightens both prior to grinding and after it's ground. Pretty wild to watch him take a hammer and chisel to a cam in the fixture!
first time I saw that done I was scratching my head for a bit. I'd think a billet cam would have some memory and just spring back after a while.
 

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LMAO!.......:)hammers
I was like ...... " how the hell is whacking that thing with a hammer and chisel going to fix it?" ..... part of the reply was " .... where do you think the term " get a bigger hammer came from" that didn't really help my comfort level ..... :)hammers
 

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first time I saw that done I was scratching my head for a bit. I'd think a billet cam would have some memory and just spring back after a while.
They can. Seen it.
Next we will be talking about straightening bent push rods:))eek:)) They should stay straight........for about 10 revolutions

Its one thing to straighten a cam that has a bow in it. Same with crankshafts. When its bent between 2 journals and its that obvious, its junk.
It makes think about taking a rod bolt that's been stretched and putting in a vice and squeezing it back. I am sure somebody has thought of it.



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first time I saw that done I was scratching my head for a bit. I'd think a billet cam would have some memory and just spring back after a while.
You assumed billet. This guy regrinds lots of oddball rare cams, and all of those get straightened prior to a regrind, and checked again after he grinds them.
 

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You assumed billet. This guy regrinds lots of oddball rare cams, and all of those get straightened prior to a regrind, and checked again after he grinds them.
Every billet cam needs to be straightened and finish ground after it comes back from the heat treater, unless it started out as a full thru hardened core.
Banging a cast cam back straight is a little different because the grain structure is crystalline and has no direction.

That's all totally different than a billet shaft that been wacked and bent over a span of 6 inches.

I don't straighten connecting rods, push rods, or bent camshafts.
I won't spend 5.00 straightening a bent crankshaft that was straight when it was made. The 2 that I did, didn't stay that way long, and the guys that did them warned me they wouldn't. It depends on the material, and the bend. Had stock cranks that were bent from day one that straightened and stayed straightened. But they were out maybe .0015 end to end. Not .005 between main journals.
They weren't all that sharp though. Some fool named Castillo in la Mirada. The other guy named Velsco made the other shaft, but what does he know.

Had both cranks ground straight, and they stayed that way until I sold them.



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One of my customers has a mirror frame made from several halved cam shafts in a hot rod themed bathroom, pretty cool lookin deal. If it doesn't have to many bad memories attached to it you could always do something like that.
 

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I have seen many cams straightened. The guy who does mine checks and straightens both prior to grinding and after it's ground. Pretty wild to watch him take a hammer and chisel to a cam in the fixture!
Same way you straighten a crankshaft. Chisel in the radius while under pressure from the straightening fixture.

It's pretty amazing.

Tell the customer right up front. It might break during the process.
 

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Not in Hal's case, but are any of you checking base circle runout too? How can you know if the cam was ground with it bent or not?
 
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