Problem with motor on Beseler 45MX enlarger

Photopathe · May 30, 2018

Hi! I have a problem with the motor on my recently bought Beseler 45MX enlarger. The motor struggles when moving the head up. Sometimes it simply won't make it. At some point I saw some fumes and a smell of burning. To add to the confusion, the next day it would work properly (it slows down in the last stretch but I assume this is normal). So it's an intermitent problem. If anyone has an idea of what might be the problem and how to fix it that would be great.
Thanks!

dpurdy · May 30, 2018

The easiest thing to do first would be to put some industrial grease on the gear teeth then motor the head up and down several times while giving some support under the cross bar or the motor box when going upwards. Those motors are very durable. I bought my MXT from a retiring photographer back in 1975 when it had already been heavily used. Then I ran a custom printing business for about 20 years with it and to this day it is my only enlarger.

faberryman · May 30, 2018

May be a dumb question, but is the motor cord caught up?

George Nova Scotia · May 30, 2018

Release of magic smoke is never a good sign. Mine slows down at the top as well. Hidden inside one of the cross pieces holding the head is counterbalance spring. It could be to tight. Instructions are in the manual. It’s not the best design -seems to get tighter as it gets near the top.

Toyo · May 30, 2018

Check that the frame has not been twisted.
This happened to mine and I had the same trouble.
I could not find a fix for it and had to source another frame from a scrapped enlarger
T

Photopathe · May 30, 2018

Thanks! Nice to have replies so quickly!
Faberryman, not a dumb question, it was my first taught but after checking no that's not the problem.
I will try dpurdy suggestion first and take it from there (will then try open the cross bar...). Will report back. Excuse my ignorance but just to be sure I'm not doing anything stupid you mean that I should open the motor box to apply industrial grease to the gear teeth inside? Or more simply apply the grease on the teeth located on metal rail along which the motor runs up and down?

Photopathe · May 30, 2018

The frame doesn't seem twisted. And sometimes it does work without a problem.

Toyo · May 30, 2018

Photopathe said:
Thanks! Nice to have replies so quickly!
Faberryman, not a dumb question, it was my first taught but after checking no that's not the problem.
I will try dpurdy suggestion first and take it from there (will then try open the cross bar...). Will report back. Excuse my ignorance but just to be sure I'm not doing anything stupid you mean that I should open the motor box to apply industrial grease to the gear teeth inside? Or more simply apply the grease on the teeth located on metal rail along which the motor runs up and down?

The motor gearbox is a sealed unit and it is unlikely to be the cause of your problems. The rack and pinions - metal rail and cogged wheels - do not need grease to work correctly and that will only cause you grief as they are exposed..
Get a screwdriver and check to see that the racks are securely screwed down to the frame - there are about eight screws holding each in place. If they have worked loose, then the racks can flex and that may be jamming the pinion wheels.

George Nova Scotia · May 30, 2018

Careful with spring in the crossbar. Follow then directions carefully if you can't find them let me know. Letting a wound spring loose can be dangerous. Not as bad as the exposed ones on some other brands but no fun to fix.

glbeas · May 30, 2018

A set of wornout brushes could be the culprit too. Even if the specific brushes arent available something close like dremel brushes can be carved to fit as long as they arent undersized.

mgb74 · May 30, 2018

First, make sure the cross bars are properly horizontal. They can slip on one side so it's not properly perpendicular to the frame. Then, make sure there's not an issue with the motor belt.

Toyo · May 30, 2018

mgb74 said:
First, make sure the cross bars are properly horizontal. They can slip on one side so it's not properly perpendicular to the frame. Then, make sure there's not an issue with the motor belt.

Yes, the belts do stretch over time - good suggestion
T

mshchem · May 30, 2018

I don't know what you have for light source? The old DG colorhead had a helper spring to lift the extra weight. The spring was part of the transformer that mounted to the crossbar. These motors always have a bit of, for me, a pleasant ozone smell. But smoke is bad. I've been using these for over 40 years never had one fail. The other thing to check is make sure that the shaft for the fine focus on the motor is not bent from something bumping it. I had a bad UPS experience, that knob got whacked and the motor would stall . It was a simple binding situation that I corrected by gently bending the shaft so it wouldn't bind. It's still a bit wobbly but works awesome . Look for anything that could be putting any extra load on the motor.

Doremus Scudder · May 31, 2018

Do check to make sure the rack-and-pinion gear hasn't jumped a tooth on one side. Adjusting the spring helps if the problem is spring tension, but if it is happening intermittently, then the spring is likely not the culprit. Does the head have problems moving down as well as up? If so, there may be friction somewhere. Make sure there is no stress on the frame from anything and no impediments to the moving stage. The rack gears are held on by screws, make sure these are all tight and that the gear strip isn't bowing out.

FWIW, when I'm raising the enlarger head fairly long distances, I help it out with my free hand (I've got a Chromega 5x7 color head mounted on one 45MX).

(Edit: MSChem's suggestion is very good too!)

Best,

Doremus

John Koehrer · May 31, 2018

Magic smoke making an appearance isn't usually a good sign #4.
I've got a motor and horizontal shafts that I'd peddle. It from a 45Mkll.

Send me a message if you would be interested.

M Carter · May 31, 2018

To check that the frame isn't twisted - I don't think you can tell by eyeballing it, and it's part of the alignment procedure to check and adjust it. I just use the cheap plastic non-digital version of this angle finder to check mine.

The spring on my MXT is shot - someone obviously broke the screw when adjusting it, there's no tension at all and the screw is just stuck in there for looks - so I help push the thing up and ease it down with my free hand. But making sure the carriage is properly aligned (level) with the teeth is a good idea and very easy to do. Start with a spirit level on one of the tubes, if the level doesn't match the baseboard you drop the whole thing out (remove the lower stop screw and I'd remove the condensers or head as well to keep the weight down), push it back up, hit the motor and check again.

mgb74 · May 31, 2018

A while back, I took apart the motor assembly. I was able to search on the motor model # itself and found sources (other than Beseler) to purchase that component.

I may also have a spare motor someplace here. PM me if you think you need one.

darkroommike · May 31, 2018

You just loosen the bar with the spring in it, no need to disassemble, you can then tighten the spring up a bit and try it again. I had an older 45 MCRX that barely moved up without a boost before I tightened the spring. The instructions go something like this, from the back loosen one of the screws while holding the bar with the other hand and then rotate the bar a bit and tighten the screw, try the motor, if you need more boost, do it again.

Photopathe · Jun 7, 2018

Thanks for all those replies! The head is a Ilford Ilfospeed Multigrade 500H, I probably should have mentioned this from the start just in case. I checked a few things that were mentionned. It never has difficulties going down, only going up. Helping it going up with the free arm does help, I guess I'll be systematically doing this from now on. I have found a basic instruction manual on the internet but nothing that seems to explain such things as complete alignment procedure or playing with the spring bar. If anyone has a more complete instruction manual available (as a pdf or jpgs) that would be great!

Mainecoonmaniac · Jun 7, 2018

Photopathe said:
Thanks for all those replies! The head is a Ilford Ilfospeed Multigrade 500H, I probably should have mentioned this from the start just in case. I checked a few things that were mentionned. It never has difficulties going down, only going up. Helping it going up with the free arm does help, I guess I'll be systematically doing this from now on. I have found a basic instruction manual on the internet but nothing that seems to explain such things as complete alignment procedure or playing with the spring bar. If anyone has a more complete instruction manual available (as a pdf or jpgs) that would be great!

Here you go!
https://www.evernote.com/l/ARoIVlzbXP1OlrVZn7Yr8bs1ZV6tFvWmbQ0

I'm thinking that on one side, of the rack, one of the gear jumped a tooth on the enlarger causing misalignment. You might have to take the assembly off the geared rail and put it back aligned. I have had my 45MXT for over 30 years and it's a great enlarger.

mshchem · Jun 7, 2018

Mainecoonmaniac said:
I'm thinking that on one side, of the rack, one of the gear jumped a tooth on the enlarger causing misalignment. You might have to take the assembly off the geared rail and put it back aligned. I have had my 45MXT for over 30 years and it's a great enlarger.

This is the first thing I would make sure was right . It can be something simple. Take the head off. If it goes up fast without the head, you may have to give it a hand. The old DG dichro head had a supplemental spring you attached to the very top to help with the excess weight of the head .

Problem with motor on Beseler 45MX enlarger

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