Need Help - Drive Belt Advice

[Alan Turner]

On my Griggio slot moritser (1980 or so vintage, got it used from an estate), there is a drive belt, 1/2" or so wide, .30 thick or so, and about 42.5" long, measured on the O.D. It may be a replacement belt. Prior owner died. The OEM sheet I have, such as it is, has no specs. The pulleys are misaligned a bit, and there is no room to get them better aligned. The are not in the same plane - out about 1/8" or so - and that is the best I can do. Can't move the pulleys, and there is no room in the case to move the motor forward. The two shafts are about 16" apart, measured from the centers.

The issue is -- is there a type of belt which will accomodate this misalignment? Poss. a link belt? Or, a special type of belt? I looked in the MSC catalog, and became confused quickly. I am not a mechanic at all. TIA

[Jim Becker]

A link belt is going to be more forgiving, but even then, having alignment would be preferable. Trying out the link belt wouldn't be horribly expensive, however...

Could you replace the pulleys with some that could give you more lateral adjustability?

[Bill Lewis]

Can't move the pulleys, and there is no room in the case to move the motor forward...
...I am not a mechanic at all.

These two statements mean to me that there might possibly be a way to better align the pulleys. Pulleys are mounted on shafts, therefore they should be able to move along the shafts. If the shafts are parallel, then the pulleys can only be out of plane with one another, and this should be correctable by adjusting either the drive or driven pulley.

The only other possible condition would be if the pulleys are out of plane with one another (shafts not parallel), e.g. the motor tilted. This too should be a correctable situation.

I doubt the manufacturer built the misalignment in to the design. Without seeing it firsthand, or with photos, it is difficult to say exactly how to fix it.

[CPeter James]

I use these on most of my machines and they do really help. I think that the 1/8" misalignment in 16" would be OK, not perfect, but it would work. They wear like iron and run smooth. This is their web site and the belting is available from you LOCAL bearing distributor.

http://www.fennerindustrial.com/prod...twist_ind.html

CPeter

[lou sansone]

hi alan

I agree with bill, but from my some 25 years of machine experience I would say that it might not be a real big problem. It will cause some vibration, but may not be that bad. Have you powered the unit up and watched the belt flutter ?

It does seem strange that the mfg would have misaligned the pullys to beging with though.


lou

[Bill Lewis]

You know you're right Lou, it may not be a problem. I naturally assumed it was, otherwise why pose the question? I just figured the belt had been worn out by the mis-alignment problem.

[Rick Lizek]

I believe I have the same Griggio mortiser in our shop and it takes a 3V 450 belt. Griggio is Italian so always think metric. 1/8" or 3.175 mm isn't a big deal. No big deal to move it closer either but it shouldn't present much of a problem being slightly off. People think the Fenner is the answer to everything. Not so in my opinion and I'm a wood machinist.
www.mcmaster.com has the belt if it is the same Griggio I have. Probably about the same vintage I suspect.

[Alan Turner]

Rick,
I ordered a MSC Direct belt, an A40, P/N 88029848, on the theory that it said this belt would tolerate slight sheave misalignment. It will arrive today, and I will try to remember to report back. I'll try your suggestion next if it does not work.
Great tool, of course, and you just about never see one of these on the used market. I got quite lucky.

[Alan Turner]

Belt worked fine, and I am back in business. thanks, guys.