Arboga Maskiner EM825

[rodm717]

Here is what i am working with. Surprisingly the bearings are mostly open and it has four composite gears. Looks like phenolic. The good news is that if the one gear is the only issue, I only lose 1060 and 250 rpm and will still be able to operate and control speed with vfd.
I cleaned out any of the debri i found. Upon reassembly, I found there was still noise and realized the gear is still in place and changing gears merely places engagement to one gear or other. The gears themselves do not move. Looks like i will have to remove material, all the teeth from the damaged gear, to eliminate the noise and prevent any damage to the good intersecting gear.
Also suppose i will be looking to replace the broken gear and hope manufacturer still uses or has same gear.
Also the three caps in the top have a hole in each center, and from what i understand, original may have had grease zirks.

 

[f350ca]

Rather disappointing to see phenolic gears. Wonder why? For quieter operation?

Greg

 

[rodm717]

Removing the teeth worked and is now running smooth and quiet. I also packed some fresh grease in the open bearings that were exposed.
Phenolic is excellent at taking heat, is strong, and quiet. I imagine it was also used to isolate and prevent damage if the spindle crashed and appears to have done that well without damaging any other components. If that had been a metal gear, there would have been a lot more damage and other components needing to be replaced.

 

[rodm717]

Unfortunately manufacturer no longer has any drawings or documentation. It's "very old machine"
I decided to do a little more clean up and take some more pictures of gearing and bearings. Really simple and may replace bearings at some point.
Currently rocking FAG 6203 open bearings. They seem good.
At this point I am not going to mess with trying to get a gear made. I believe 415 rpm gearing has plenty of torque at spindle for my needs. Dropping it down with vfd should be fine.

 

[rodm717]

Finally received new micro breaker/disconnect for in front of vfd and will be able to permanently wire.
One of the next projects is going to be putting a slot into the Mt3 ER32 adapter and machining a split plate to utilize the stock nut in mechanically securing the adapter to the spindle.
Currently working between this, a complete headstock rebuild on my Enco
110-2034 lathe and a complete rebuild/refurb of a 1941 Southbend 9A 4' lathe. Very busy, but while I'm waiting for parts or information on one, I'm actively working on another.
While the manufacturer put me off, I can't help but wonder if the newer U2508 uses the same gear setup. Maybe I'll try them again.

 

[rodm717]

Having utilized the machine for a few various milling and drilling projects, I will be replacing the bearings and making new shims that are utilized in securing the bearings and keeping shafts stiff. Runs well, but milling there is definitely some tightening up to do in the gear train. The surface finish is pretty good, but you can hear some slop and noise in the gear train. It's not the phenolic and im tracing back from there. I'll also take a harder look at the snap rings, ect., keeping the gears in place and linkage for shifting. I do believe i will be going with sealed bearings over the open ones that are in there now. They are not immersed in oil or getting any active lubrication, so i believe sealed is the way to go. Fag 6203/c3 rubber sealed, unless i get any constructive info to do otherwise.
I also need to look at the longitudinal acme nut or handwheel tensioning and adjust. There is about .005" of backlash, but can feel it when milling vertically or utilizing length of end mill.
So far extremley happy with purchase and added utilization in my home shop. I've used to make back pulley shaft mounting caps for my Enco 110-2034 and a custom part for work, a carrier piece used in a automated wet/powder part conveyor system.

 

[extropic]

@rodm717

Are you running without using the damaged gear(s)?

What is your plan regarding replacing the damaged gear(s)?

 

[rodm717]

@rodm717

Are you running without using the damaged gear(s)?

What is your plan regarding replacing the damaged gear(s)?

Yes, the damaged gear was used in one of four mechanical gearing scenarios along with two motor speeds for a total of eight stock spindle speeds.
So i lost 4. But, not really, since i am utilizing a vfd, the machine is capable of virtually any spindle speed up to 3450 rpm. The four usable mechanical gear scenarios allow me to utilize different torque for milling. The vfd allows for different speeds, but , you lose torque at low spindle speeds with a a/c vfd.
If you look back to my previous post, i described what i did to take the damaged gear out of the equation and basically keep it out of engagement.
I am not looking to replace the gear at the moment, since i cannot find one available and will need to be custom made. When i change out bearings i may remove it altogether and also make a template from a good gear to make one in future. I need to use utilize this machine in making parts for some of my other machine projects.

 

[Sblack]

I have a manual. There isn’t much to it but I‘m happy to pass it along.

 

[Sblack]

I have idea on how the fine feed quill works on that machine but I found some information about it here:

Arboga EM825, U2508 Cont.

Universal Machine Tool for vertical and horizontal milling, lathe work, shaping, slotting filing and grinding as badged by Arboga, AB Skania Verktyg, Eskilstuna Tools<br>UM400 Miniature Combination Machine

www.lathes.co.uk

It also seems that there is a few different manuals available for it here, but they are not free:

Arboga | store.lathes.co.uk

store.lathes.co.uk

You engage the fine feed by moving the coarse feed handle inwards. That engages the worm wheel.