replacing chains

[Skiddy]

I am going to replace the chains on my 642B where can I buy a reasonably priced breaker. Anyone know what number of chain they use in the 642B

 

[Tazza]

Angle grinder is all you need. Cut a link and buy a new link, easy! Just cut the larger section that the new link will replace (if that makes sense). Cut through it, pull the chain out then grind the end of the pins that hold the sides on and use a pin punch to knock the pins out. Install back in the chain case install a new link and you are set. The links are cheaper than i expected, i think a set i got for 3/8" chain were 80c each. Your machine will use larger chain though, but its just a guide.

 

[Skiddy]

Angle grinder is all you need. Cut a link and buy a new link, easy! Just cut the larger section that the new link will replace (if that makes sense). Cut through it, pull the chain out then grind the end of the pins that hold the sides on and use a pin punch to knock the pins out. Install back in the chain case install a new link and you are set. The links are cheaper than i expected, i think a set i got for 3/8" chain were 80c each. Your machine will use larger chain though, but its just a guide.

I was told not to use a master link. He said they are the weak link in the chain. ????????????????

 

[Tazza]

I was told not to use a master link. He said they are the weak link in the chain. ????????????????

The ones i got would be just as strong, the steel was the exact same gauge and no doubt just as hard as the chain. The weak point i can see is the clip, but if you clip it on its not going to fall off.

 

[Skiddy]

The ones i got would be just as strong, the steel was the exact same gauge and no doubt just as hard as the chain. The weak point i can see is the clip, but if you clip it on its not going to fall off.

The chains that are in my bottom end do not have any sort of master link. Any one know where I can get a chain breaker/mender? I will have the chain out this week end so I will know the pitch.

 

[OldMachinist]

The chains that are in my bottom end do not have any sort of master link. Any one know where I can get a chain breaker/mender? I will have the chain out this week end so I will know the pitch.

The reason there's no master link is Bobcat sells them a completed loop. They say they are pre-stretched and will last longer than a normal off the shelf chain that will stretch over time. I know several members here have said they replaced their chains with aftermarket chains and master links and have had no problems that they've mentioned. McMaster Carr http://www.mcmaster.com/ has chain breakers but depending on your chain size they can be pricey

 

[Land-Tech]

The reason there's no master link is Bobcat sells them a completed loop. They say they are pre-stretched and will last longer than a normal off the shelf chain that will stretch over time. I know several members here have said they replaced their chains with aftermarket chains and master links and have had no problems that they've mentioned. McMaster Carr http://www.mcmaster.com/ has chain breakers but depending on your chain size they can be pricey

I've replaced the chains and the masterlinks work fine. there is a difference in quality between brands.Ask if they have brands or different grades of chain. I went through two separate events where the chain broke at the most difficult of places.This is within a month of buying new chain. Took the chain back and a guy with experience, ( every shop has a person like that , they are just never there when I come) pointed out that there other choices and that the buyers on the oil industry will only order this certain brand. Both chains tensile out tthe same to the same strength according to the info on the boxes . Take a look at the pic below and tell me which one is the bogus one. This happened ten years ago and maybe the bogus manafacture has refined there product. There was a ten dollar diff in price. Scott

 

[OldMachinist]

I've replaced the chains and the masterlinks work fine. there is a difference in quality between brands.Ask if they have brands or different grades of chain. I went through two separate events where the chain broke at the most difficult of places.This is within a month of buying new chain. Took the chain back and a guy with experience, ( every shop has a person like that , they are just never there when I come) pointed out that there other choices and that the buyers on the oil industry will only order this certain brand. Both chains tensile out tthe same to the same strength according to the info on the boxes . Take a look at the pic below and tell me which one is the bogus one. This happened ten years ago and maybe the bogus manafacture has refined there product. There was a ten dollar diff in price. Scott

I'd say the chain on the right is the cheap one.

 

[OldMachinist]

I'd say the chain on the right is the cheap one.

Okay because of the way my mind works I wanted to dig a little deeper into roller chains. As stated roller chain strength can vary greatly. I looked at size 80 steel chains as an example and found working loads from 1,700 lbs up to 4,100 lbs because of different grades of steel and design. Also I looked at if there much difference between using a fully riveted chain and a master link connected chain. Again in size 80 using a chain in the mid range a loop with a master link was rated at 1,733 working load and the fully riveted chain at 2,600 lbs. In size 100 the difference was 2,727 lbs. vs. 4,091 lbs. The price difference between the lowest rated chain and the highest was only a couple of dollars per foot. Anyway this really just to satisfy my curious mind and is not meant to start any controversy.

 

[Land-Tech]

Okay because of the way my mind works I wanted to dig a little deeper into roller chains. As stated roller chain strength can vary greatly. I looked at size 80 steel chains as an example and found working loads from 1,700 lbs up to 4,100 lbs because of different grades of steel and design. Also I looked at if there much difference between using a fully riveted chain and a master link connected chain. Again in size 80 using a chain in the mid range a loop with a master link was rated at 1,733 working load and the fully riveted chain at 2,600 lbs. In size 100 the difference was 2,727 lbs. vs. 4,091 lbs. The price difference between the lowest rated chain and the highest was only a couple of dollars per foot. Anyway this really just to satisfy my curious mind and is not meant to start any controversy.

All the machines I have, the chains are fitted with master links of various types and have had no problem. In the above pic the chain on the left is the cheap chain that broke and notice no wear. the one on the right is a japanese manafacture and the one on left is not. The one on the right was original that I replaced after I found water in the chaincase and replaced because I was worried that it was weakened. You can see the wear.
I have a hard time relying on manafactures specs anymore but thats all the info we sometimes have. Machine specs that you see on the web site and brochures bother me too. Knock-offs are common but they are getting better. I like to see a consumer report sort of thing where the the specs are tested using the same cryteria.
I just wanted to show a real example of what I found, so people will have a heads up when they go and purchase the chain.The bobcat chain is probably the best choice but all my machines use a masterlink from the factory.Scott

 

[Tazza]

All the machines I have, the chains are fitted with master links of various types and have had no problem. In the above pic the chain on the left is the cheap chain that broke and notice no wear. the one on the right is a japanese manafacture and the one on left is not. The one on the right was original that I replaced after I found water in the chaincase and replaced because I was worried that it was weakened. You can see the wear.
I have a hard time relying on manafactures specs anymore but thats all the info we sometimes have. Machine specs that you see on the web site and brochures bother me too. Knock-offs are common but they are getting better. I like to see a consumer report sort of thing where the the specs are tested using the same cryteria.
I just wanted to show a real example of what I found, so people will have a heads up when they go and purchase the chain.The bobcat chain is probably the best choice but all my machines use a masterlink from the factory.Scott

I too would have said the one ot the right, the links look thinner.