Replacing bar tips

[Dan F]

A quick search the other day didn't turn up much, so I thought I'd ask... How hard is it to replace the noses on bars?

I just bought a used 372XP and the bar is showing some wear, though the worst is on the nose. It's got a replaceable nose, but that's something I've never done. If I can save $20 or so, it would be worth it right now. I think it's an Oregon bar (24"). The rails are starting to get a little bit of a groove in them, I assume that would need to be addressed when a new nose was put on?

Any and all help is appreciated!


Dan

 

[Kneejerk Bombas]

The actual changing is easy, you punch out the rivets with a hammer and punch, they are soft aluminum. Then pull out the old tip, insert the new tip, put the new rivets in (they come with the tip), and peen them over with the hammer.
Finding the exact tip you had in there can be a trick. I've had the problem of the tip being a slightly different length, which changes the drive link count on the chain you need.
Another issue is, by the time the tip is worn out, the bar is usually way more than 1/2 way gone. So you change out the tip for $20 and it won't be long before the rest of the bar is junk.
As bars age with use, they tend to wear the thickness of the bar rails, on the inside. Typically, one rail will become thinner than the other, and wear at a different rate, causing the saw to cut crooked. This wear occurs on the inside of the grove where you cant see. As bars get older they need more and more dressing to keep them cutting right.
If you dress your bar and then measure the rails in a few spots with a micrometer, and they are very similar, then maybe it would be worth trying to get more miles out of it by changing the tip. If there is perceivable differences in rail thicknesses, don't throw any more money at it.

 

[Dan F]

I just dressed the bar today with a mill bastard file... I need to get one of those fancy ones, but the MB is what I had on hand...

I checked with feeler gauges, I can get to the bottom of the groove with .050 easily, I think I may have been able to get as much as .052 in there. However, at the depth of the drive links, I could put in about .056. I don't have a micrometer, and I'm not sure how you would measure rail thickness with one- aren't the rails too close together?

The bar itself is in decent shape. As I said, the most severe wear is at the tip, right behind the sprocket, probably from the chain being too tight, too often. Would pics help?

I'll have to find out exactly what bar I have, and see if the local dealer has the tips. Bailey's has them for ~$13, I'm told the local dealer has the whole bars for ~$35.


Dan

 

[Kneejerk Bombas]

Pictures alway help.
When you get chipping just around the tip, that's from running the chain too loose. The centrifugal force of the chain running around the tip lifts it off the rails and then slaps it back down, causing the damage you see. A tight chain keeps the chain close to the rails and reduces this problem.

 

[Dan F]

Ok, it was probably too loose then.

I'll see if I can get some pics in the next day or two.

Thanks, Mike.

 

[Kneejerk Bombas]

My pleasure Dan! I learn more from my posts than I teach, I bet. That's how come I'm so darn smart!

 

[Dan F]

I took some pics today.

The first is of the nose, the top is obviously worn worse than the bottom is. The second is the other side of the bar. The third is the numbers stamped on the bar. The end of the second line is "926420 GB", if it's not clear enough. I'm still not sure who the bar manufacturer is, but I'm thinking its either Husky or Oregon.

Oh, the fourth picture? If anyone can A)tell me what it is (yes, I know what it is) and more importantly, B)tell me how to make it work, I will be eternally grateful!!

I tried to take some pics down the length of the bar without the chain on, but it's really hard to see much.

Thanks!


Dan

 

[jokers]

Yeah Dan, That`s an Oregon bar.

Russ

 

[Dan F]

Thanks, Russ. Do you know what RSN I need for it, by chance?

 

[bwalker]

Replaceable Sprocket Nose.

 

[Dan F]

Yeah, I know RSN stands for that. What I was asking is what PN do I need?


Dan

 

[ray benson]

Looks like # 30853, .050 gauge.
http://www.oregonchain.com/pdf/bars/BarNoses_FB0601.pdf

 

[zombywoof]

Try going to bailey's and getting one of the Carlton (Oregon style) replaceble noses. They last longer than Oregon's and are CHEAPER!

 

[Kneejerk Bombas]

Like I warned you, the new tip might be a different size and change the drive link count.
I'd just change the bar. It'll make the saw look like new and make you feel all warm and tingly inside.

 

[n9viw]

The actual changing is easy, you punch out the rivets with a hammer and punch, they are soft aluminum. Then pull out the old tip, insert the new tip, put the new rivets in (they come with the tip), and peen them over with the hammer.

Just thought I'd set the record straight, but at least as far as my saw was concerned, the above information is partially WRONG.

I purchased a replacement .404 nose for my Oregon bar from ebay user kpoutdoors (EXCELLENT transaction, btw), which came with replacement rivets. This is the old three-rivet style, not the new one-rivet style, so your comment may indeed be correct, if the one-rivet style comes with aluminum rivets. Mine, however, came with STEEL rivets, proven out by the use of a welding magnet, and the rust on one of the old rivet heads.

As such, it was not as easy as described. I had to drill out the rivet heads with a 3/16" drill bit, then punch out the remainder once I'd drilled through the head. I replaced the nose, inserted the rivets one at a time and peened them over with a ball-peen hammer and a tapered punch, using a section of railroad rail as an anvil (no vise yet).

So, as I said, the new ones may indeed be aluminum, but mine certainly were not. No harm, no foul, as I got the job done, just didn't want someone else to spend the time I did, whanging away at these things wondering why they won't just 'come out'.

Nick