alignment bar question

[altitude 411]

Hey team, I was having a heck of a time with my alignment. Bar slides in somewhat easy then somewhat hard then easy again. I'm wondering what the??? I took the bar to a friends shop and put it on the lathe with a mic and see that it has .005 run out.
1) Is this enough to be a problem?
2) if I true it up would it be then too small on the end to give an accurate alignment?


My question to the seller is how do you spin a bar on a lathe with a .005 run-out?? Bad chuck? Postal service dropped the shipment? Doesn't seem that it would bend that easy... Seller is on e-bay with lots of sales and good reviews. Anyone check their bar for run-out?

 

[HT32BSX115]

I took the bar to a friends shop and put it on the lathe with a mic and see that it has .005 run out.
1) Is this enough to be a problem?
2) if I true it up would it be then too small on the end to give an accurate alignment?

Howdy,

Someone bent it! I made my own alignment bar on my neighbors lathe and it's "spot-on"

I wouldn't just turn it down to "true" it up though. Just shorten it a little and make the "new" part using the right dimensions.

If you need it longer, you can easily make an extension for it.

Here's a link to info on dimensions. I made mine like the one shown in the picture

https://forums.iboats.com/forum/eng...s/338200-miscellaneous-mercruiser-information

Cheers,


Rick

 

[altitude 411]

Perfect idea thanks Rick. I did find this which states that +/- .005 tolerance is acceptable, but I'm sure that is for diameter and not run-out... I thought this was a precision instrument.

 

[stang32]

they are cheap now a days, you can find them under 50 bucks. why go through the hassle

 

[HT32BSX115]

they are cheap now a days, you can find them under 50 bucks. why go through the hassle

True, But I looked all over the yard and couldn't "find" one. So, I would have had to buy one online and wait to have it shipped to me only to find out it was bent......Then send it back and wait for another one.

Of course, If I had a bent one and access to a lathe, I'd just shorten it a few inches and "fix" it.

That still seems a little more "hassle" than the 30-45 min I spent turning that piece of steel on the lathe.

..... ymmv......

 

[HT32BSX115]

Perfect idea thanks Rick. I did find this which states that +/- .005 tolerance is acceptable, but I'm sure that is for diameter and not run-out... I thought this was a precision instrument.

You're right and 0.005" isn't much. You might just be able to just "tweak" it "straight"

Otherwise, you can just chuck it up and re-machine it, and only losing 2.2" or so.