Re: motor acted funny the other day
What about a simple motor controller with overload protection (aka a heater)?
On Dec 30, 2019 02:42, Jerry Durand <jdurand@...> wrote: I figure the standard green button to start, red to stop.? Green closes the relay and starts a ramp-up timeout.? After that each spoke passing is timed.? Too long, kill power.
And, of course a switch to detect the cut is done.? That kills power immidiately.
---
Jerry Durand
Durand Interstellar, Inc.
On Dec 29, 2019, at 23:38, "Robert Downs via Groups.Io" < cs.com@groups.io target=_blank> [email protected]> wrote:
It will have to have a manual override switch to start it.
?
?
?
I was figuring an inductive sensor reading the wheel spokes.? Simple, doesn't care about dirt/damp.
Something like one of these:
I once replaced all the optical sensors on a production line with inductive ones.? Suddenly we stopped getting service calls all the time.? When I gutted the motor controller box and reduced it to about 4 parts that solved most of the rest of the calls.
The engineer who designed the system was pissed when he saw what I did.
The production manager, however, was delighted.
Durand Interstellar, Inc.
On Dec 29, 2019, at 23:02, John Vreede <vreededesign@gmailcom> wrote:
Yeah I've thought about that too Jerry.
Do you have any particular sensor in mind?
I wonder if a sensor on the motor might be better, as its the motor you're trying to protect.
If it loads up so the motor rpm drops to 1250rpm, it will stall almost immediately it drops any lower, so a sensor that cuts the power between 1300 and 1250 rpm would be ideal.? There must be an electric/electronic solution.? Anyone out there who can comment? - jv??
|
Re: motor acted funny the other day
I figure the standard green button to start, red to stop.? Green closes the relay and starts a ramp-up timeout.? After that each spoke passing is timed.? Too long, kill power.
And, of course a switch to detect the cut is done.? That kills power immidiately.
---
Jerry Durand
Durand Interstellar, Inc.
It will have to have a manual override switch to start it.
?
?
?
I was figuring an inductive sensor reading the wheel spokes.? Simple, doesn't care about dirt/damp.
Something like one of these:
I once replaced all the optical sensors on a production line with inductive ones.? Suddenly we stopped getting service calls all the time.? When I gutted the motor controller box and reduced it to about 4 parts that solved most of the rest of the calls.
The engineer who designed the system was pissed when he saw what I did.
The production manager, however, was delighted.
Durand Interstellar, Inc.
On Dec 29, 2019, at 23:02, John Vreede <vreededesign@gmailcom> wrote:
Yeah I've thought about that too Jerry.
Do you have any particular sensor in mind?
I wonder if a sensor on the motor might be better, as its the motor you're trying to protect.
If it loads up so the motor rpm drops to 1250rpm, it will stall almost immediately it drops any lower, so a sensor that cuts the power between 1300 and 1250 rpm would be ideal.? There must be an electric/electronic solution.? Anyone out there who can comment? - jv??
|
Re: motor acted funny the other day
It will have to have a manual override switch to start it. ? ?
toggle quoted message
Show quoted text
From: [email protected] [mailto:[email protected]] On Behalf Of Jerry Durand
Sent: Monday, December 30, 2019 01:17
To: [email protected]
Subject: Re: [4x6bandsaw] motor acted funny the other day? I was figuring an inductive sensor reading the wheel spokes.? Simple, doesn't care about dirt/damp. Something like one of these: I once replaced all the optical sensors on a production line with inductive ones.? Suddenly we stopped getting service calls all the time.? When I gutted the motor controller box and reduced it to about 4 parts that solved most of the rest of the calls. The engineer who designed the system was pissed when he saw what I did. The production manager, however, was delighted.
Durand Interstellar, Inc. On Dec 29, 2019, at 23:02, John Vreede <vreededesign@gmailcom> wrote: Yeah I've thought about that too Jerry.
Do you have any particular sensor in mind?
I wonder if a sensor on the motor might be better, as its the motor you're trying to protect.
If it loads up so the motor rpm drops to 1250rpm, it will stall almost immediately it drops any lower, so a sensor that cuts the power between 1300 and 1250 rpm would be ideal.? There must be an electric/electronic solution.? Anyone out there who can comment? - jv??
|
Re: motor acted funny the other day
I was figuring an inductive sensor reading the wheel spokes.? Simple, doesn't care about dirt/damp.
Something like one of these:
I once replaced all the optical sensors on a production line with inductive ones.? Suddenly we stopped getting service calls all the time.? When I gutted the motor controller box and reduced it to about 4 parts that solved most of the rest of the calls.
The engineer who designed the system was pissed when he saw what I did.
The production manager, however, was delighted.
---
Jerry Durand
Durand Interstellar, Inc.
Yeah I've thought about that too Jerry.
Do you have any particular sensor in mind?
I wonder if a sensor on the motor might be better, as its the motor you're trying to protect.
If it loads up so the motor rpm drops to 1250rpm, it will stall almost immediately it drops any lower, so a sensor that cuts the power between 1300 and 1250 rpm would be ideal.? There must be an electric/electronic solution.? Anyone out there who can comment? - jv??
|
Re: motor acted funny the other day
Yeah I've thought about that too Jerry.
Do you have any particular sensor in mind?
I wonder if a sensor on the motor might be better, as its the motor you're trying to protect.
If it loads up so the motor rpm drops to 1250rpm, it will stall almost immediately it drops any lower, so a sensor that cuts the power between 1300 and 1250 rpm would be ideal.? There must be an electric/electronic solution.? Anyone out there who can comment? - jv??
|
Re: motor acted funny the other day
I'm thinking when I change out the start switch for a magnetic one I might add a movement sensor for the upper wheel.? Stops turning, turns off the power.
---
Jerry Durand
Durand Interstellar, Inc.
On Dec 29, 2019, at 17:46, hepps_29646 < orwhut@...> wrote:
My motor was slow to start.? When I put on a new capacitor the difference in starting speed was remarkable.? Then I left it sawing and it hung in the cut and all the smoke got out.? You're wise not to leave yours unattended.
|
Re: motor acted funny the other day
My motor was slow to start.? When I put on a new capacitor the difference in starting speed was remarkable.? Then I left it sawing and it hung in the cut and all the smoke got out.? You're wise not to leave yours unattended.
|
Re: motor acted funny the other day
I made just a couple of cuts a couple days ago and it ran fine. I've got a couple more cuts (this time just some small angle iron an inch or so) so I'll see how that goes.
On Friday, November 8, 2019, 12:51:47 PM EST, John Vreede <vreededesign@...> wrote:
Jims reply is much more likely - intermittent contact, esp if its never been stalled.?
My only experience with a bad capacitors (on 2 different motors) was that the motors ran unsteadily for a few seconds and then lots of smoke and they stopped.? Replaced capacitors and they've been good ever since - jv
|
Thank you for including me in the transfer!
|
Re: motor acted funny the other day
Jims reply is much more likely - intermittent contact, esp if its never been stalled.?
My only experience with a bad capacitors (on 2 different motors) was that the motors ran unsteadily for a few seconds and then lots of smoke and they stopped.? Replaced capacitors and they've been good ever since - jv
|
?Me too! All automatic
on my end. Got an email that I'd been added to groups.io and
since the subject line still includes the name of the group in
brackets just like the old one did, [4xgbandsaw], even my filter
rule in my Thunderbird email program properly sorted it to the
proper 4x6 folder in my email. Perfect!
On 11/7/2019 7:25 PM, Jerry Durand
wrote:
toggle quoted message
Show quoted text
I see the move is complete, thanks!
|
What a relief and THANK YOU!? I was just thinking about the 4x6 group.? Hopefully this new home will preserve everything from the files after the Yahoo purge.Orwhut
|
I see the move is complete, thanks!
--
Jerry Durand, Durand Interstellar, Inc.
tel: +1 408 356-3886
|
Re: motor acted funny the other day
my motor has 2 of the "big lumps" and then another square box with the power cord going into it. I was wondering if it may have something to do with the caps. I always plug it in to the same group of outlets that I plug other things into so I'm doubting a problem at the output. The 'letting the smoke out" I also doubt because the saw has never ran un attended. It's actually ran very little and I'm always right there nursing it along. Often with tubing or blackpipe I control the downspeed when it gets to where it would possibly feed itself down to fast just by hand,putting a little more pressure with my fingers to prevent it from dropping too quickly and possibly binding the blade. If I continue to have the problem I'll look into the various wiring junctions. With it unplugged of course. I know some years ago I bought an electric meat smoker and it quit working in about a month and when I looked at the wiring at the heating element the female spades that went to the male spades of the element were totally gone. All that was left of them were the area where they were crimped around the wire,so that got me thinking maybe the wiring in the saw is using some pot metal type of terminals and the trip here from china get's some salty air to them and speeds up the disintegration process.
? I also was just wondering if one of the caps are just going bad. I have a little more sawing to do on a project I'm working on now,cut a threaded rod and a few cuts in some small angle iron so I'll see how that goes.
On Thursday, November 7, 2019, 5:37:31 PM EST, Jim.Klessig@... <jim.klessig@...> wrote:
Assuming your motor cap start/Cap run type, (big lump on the side of the cylinder that is?your motor)?I would suspect that based on your description, you have a loose wire connecting to the run Cap. Without that connection your motor (if it is that type) can not generate significant torque.
I doubt it is "having? let the smoke out"-Yet.
I suspect loose wiring because it started working again.? If the cap was bad, then that more than likely would not have happened. This would be in your motor terminal compartment more than likely.
It is also possible that you just have a bad power connection, that is giving your motor reduced voltage, enough to turn unloaded, but not enough to run under load. This could be anywhere from your motor terminals, to your switch, and all the way to your plug, extension cord or wall socket.
Unplug your motor before you look at any of these areas.
im no electrician either, but I am an engineer.
|
Re: motor acted funny the other day
Assuming your motor cap start/Cap run type, (big lump on the side of the cylinder that is?your motor)?I would suspect that based on your description, you have a loose wire connecting to the run Cap. Without that connection your motor (if it is that type) can not generate significant torque.
I doubt it is "having? let the smoke out"-Yet.
I suspect loose wiring because it started working again.? If the cap was bad, then that more than likely would not have happened. This would be in your motor terminal compartment more than likely.
It is also possible that you just have a bad power connection, that is giving your motor reduced voltage, enough to turn unloaded, but not enough to run under load. This could be anywhere from your motor terminals, to your switch, and all the way to your plug, extension cord or wall socket.
Unplug your motor before you look at any of these areas.
im no electrician either, but I am an engineer.
|
Re: motor acted funny the other day
Hi James I'm no electrician but I suspect that at some time the motor has been stalled before and its 'let some of the smoke out'.? What happens when it stalls is that the current in the copper windings rises drastically and the insulating coating on the wire starts to melt, then burn.? Even melting the insulation is bad because the thickness of insulation between wires where they touch one another decreases and the insulation value between the wires and from the wires to ground decreases too. The effects are cumulative; if it burn would burn out in 30 secs, then 5 lots of 6 seconds will burn it out too, even if it appears that the motor was OK after each stall, the damage mounts up. The only way to know if that's really the case is to have an electrician Megger the windings.? They put a high voltage on the windings and measure the resistance to ground; there are accepted values for what it should be and when its failing. Might be some useful info for you in this doc,? Replacing 4x6 bandsaw motors v3.pdf???(its in the files section) Rgds - jv
|
motor acted funny the other day
I've got the black bull 4x6 I noticed the motor says clark on it. Haven't used it much and maybe have had it a couple years. Anyway,the other day I started to cut some tubing 1/2 inch or so and made a couple cuts and all was fine.Went to cut another piece and the motor stalled out just as I started to make the cut. It wasn't the blade got bound up it was just that the motor seemed like it had very little torque. It still had power to it and was trying to rotate but just couldn't make itself go. Lifting the blade off the workpiece it resumed normal speed then lowering the blade back down as soon as it touched the work piece it stalled the motor again. I just turned it on and off a couple times and turned the motor with it off and it was all normal. Turned it back on and made a few cuts and it worked fine. I'm just wondering if anyone has any ideas what might have been going on?
|
Hi Your saw appears same construction as most of the rest of us except that all ours have some slack in the tongue and groove joint between the guide bar (attaches to saw frame) and guide bracket (has the rollers on it). People say these saws are identical, but they're not.? Your manfr. didn't think adjustment here was necessary so didn't provide it, where every other mnfr. did. Don't be afraid to take a file to the tongue on the guide bar to give yourself adjustment to get the blade vertical.? A wedge of material needs to be taken off both sides of the tongue like in the (crude) drawing attached.? But remember that the guides are 'handed' so the material removed from the bottom guide bar will be opposite hand to the top one. 2 small set screws in the side of the bracket groove (on opposite corners) are all that's necessary to set the amount of twisting of the joint and are really helpful in setting up for square cutting, but again they'll be on opposite sides top and bottom I put 4 screws in each joint on mine (pictured) but only 2 are necessary to stop it untwisting from the setting you give it - jv Hydraulic downfeed is one of the very best mods to make, you can use coarse TPI blades to cut thin stuff and is essential if you cut a lot of tube.? Blade scrapers are better than brushes (see? ?Liquid coolant lube on a 4x6 bandsaw.pdf? in the files section?and, yes, you'll really benefit from a stiffer stand. Rgds - jv?
|
Re: Oil way or grease nipples in main pivot area?
Agree that lubing the pivot is right. You just don't remember to squirt with CRC often enough and most of those type lubes evaporate, (maybe not WD40??) so grease zerk is best.??
Did it on my saw:?
With head horizontal, tapped the pivot shaft out of one bearing supporting the head on a block of wood under the saw frame, drilled through ear 3mm, then drill partially 5mm and tapped M6 for zerk. Suck/wipe it clean of swarf/debris, then tap the axle back out the other way and repeat on the other side.
I dont believe it weakens the bearing unduly - jv
|
Hi, been a member of the Yahoo group for a while and got a lot of info from it.
This is my first post as far as either of the groups are concerned.
I have been rebuilding my old 4x6 saw and is now nearly done.
I only have to complete the wiring and rebuild the blade guides (needs new bearings)
I could never get the blade to run true as the blade guides could adjust up and down but could not twist.
From this group I found out that the up/down grove/key should have some space build into the top of it to allow the guide to tilt forward/back to allow the blade to be adjusted 90 degrees to the work piece.
My blade guides have zero space or shall I say a near perfect fit on the up/down slide. So something that I will have to fix as well.
After the rebuild is completed I want to upgrade with a?hydraulic feed control cylinder, blade brush and a proper stand.
I attached some photos
|
Jerry Durand
John Vreede
Endlesshunt