Author Topic: could use some help with a diy belt grinder  (Read 7913 times)

Offline Neubert1975

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could use some help with a diy belt grinder
« on: August 04, 2015, 10:03:12 AM »
Hi all
I have made my self a belt grinder, and after the build i found out that i needet a larger drive wheel, wich i made.
But i have a problem, when i start the motor the belt pulls to the motor side, and when i turn it off it wants to run of the grinder  :bugeye:.
Belt is 3x72" mortor 2 Hp drive wheel 190mm

Any idears what wrong here ?


Offline Arbalist

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Re: could use some help with a diy belt grinder
« Reply #1 on: August 04, 2015, 10:30:53 AM »
Crowning the wheels will help but you'll probably need some kind of tracking adjuster as well.

Offline Neubert1975

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Re: could use some help with a diy belt grinder
« Reply #2 on: August 04, 2015, 10:36:03 AM »
Hi
Thank you for the reply.
There is an adjuster wheel the one hanging near the motor, it is crowned some, but i dont know if its enough ?

Offline bertie_bassett

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Re: could use some help with a diy belt grinder
« Reply #3 on: August 04, 2015, 11:52:48 AM »
from looking at the pic, it seems tht your tension adjuster isn't parallel to you other wheels,( looks like its drooping from here)
that would easily make the belt run uphill towards the motor whilst running.

with regard to crowning, I think Arbalist was meaning the main drive wheels, not the adjuster. though while it may help the belt stay centralised, I think it would also ruin the flat surface I assume you require for a belt grinder.

as Arbalist also recommended, a tracking adjuster may well be what is required to actively hold the belt in the right place.
maby 2 rollers would be best, one each side of the belt, possibly fabricated into your tension adjuster?
a competent engineer uses the tools and knowledge available, to get a challenging job done.

 An incompetent "engineer" tells his boss that the existing equipment "can't do the job" and to get another machine

Offline trapper

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Re: could use some help with a diy belt grinder
« Reply #4 on: August 04, 2015, 12:58:44 PM »
Normally theres two rollers one has adjustment so after you have put a new belt on you can start it then adjust the roller until the belt goes central-if your is doing what you say it is the rollers

Offline Neubert1975

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Re: could use some help with a diy belt grinder
« Reply #5 on: August 04, 2015, 01:11:22 PM »
Hi thank you all for your reply.
Ill grab some food and then i will go out a check the alignment of the rollers with a metal bar, and if needet adjust them  :beer:

Offline Arbalist

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Re: could use some help with a diy belt grinder
« Reply #6 on: August 04, 2015, 03:33:46 PM »
My belt sander has only two wheels, both of which are crowned. I believe you can get away with only one of them being crowned but I'm not sure having a crowned adjuster wheel is doing you any favours. Try crowning the driving wheel if you can and see how that works. Just a simple wooden temporary version will prove the point. If you have to use a third "adjuster" wheel I suspect it would be better uncrowned.

Offline Neubert1975

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Re: could use some help with a diy belt grinder
« Reply #7 on: August 04, 2015, 03:57:40 PM »
The one i have made is with 4 wheels, but i do see your point in not having the adjuster wheel crowned, so i will try to "decrown" it
On top of that i did find out that boath the adjuster wheel and the motor wasent lined up with those on the front, so tonights project will be to fix that, it must help on it, and if not then i can try to crown the drive wheel.
Thanks for the help so far, and i will get back with the outcome of tonight  :med:

Offline Arbalist

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Re: could use some help with a diy belt grinder
« Reply #8 on: August 04, 2015, 04:07:05 PM »
Might be worth having a look on some of the knife making sites for ideas as well. Belt grinders seem to be one of the primary tools for small scale knife making and many folks make their own grinders.

Offline chipenter

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Re: could use some help with a diy belt grinder
« Reply #9 on: August 04, 2015, 04:07:39 PM »
I have an old linisher and if the belt gets hot on one side it expads and moves away from the hot side , the ajustment is quite senative .
Jeff

Offline Neubert1975

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Re: could use some help with a diy belt grinder
« Reply #10 on: August 04, 2015, 04:21:29 PM »
Arbalist
Your right about that, when i seartch for the grinder, most sites i came to were related to knifes, wish we had one back when i made knives, took almoast a whole day to make a blade from old files and so

Offline Manxmodder

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Re: could use some help with a diy belt grinder
« Reply #11 on: August 04, 2015, 04:56:36 PM »
Neubert, I would agree with Arbalist that the tension adjuster idler wheel being crowned  isn't going to be very effective at stabilising the belt tracking. A generous crown on the drive wheel is where I would start,and add crown to the driven wheel only if necessary....OZ.
Helixes aren't always downward spirals,sometimes they're screwed up

Offline Neubert1975

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Re: could use some help with a diy belt grinder
« Reply #12 on: August 04, 2015, 05:48:52 PM »
Manxmodder
Thank you, i did realign the motor and wheels, and removed the crown from the adjuster, all of  it helped alot,
but could use a little more stability, so if i got the time for it tomorrow, then i will crown the drive wheel.

Thank you all for nice and fast help  :beer:

Offline Neubert1975

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Re: could use some help with a diy belt grinder
« Reply #13 on: August 06, 2015, 05:00:25 PM »
Managed to crown the drive wheel yesterday, and today som other little things, now i have a well working belt grinder  :D
Thank you all for the help.

No its on with next project, a rotary table for the mill  :thumbup:

Offline Arbalist

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Re: could use some help with a diy belt grinder
« Reply #14 on: August 07, 2015, 05:59:28 AM »
Nice one, glad you managed to get it sorted.  :thumbup:

Offline Neubert1975

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Re: could use some help with a diy belt grinder
« Reply #15 on: August 07, 2015, 06:07:02 AM »
Nice one, glad you managed to get it sorted.  :thumbup:

Thank you, so am i, only thing left is to tro ty reduce the noice from it, but that not as important as the rotary table  :dremel: