"New" Gorton Grinder Needs Bearings, and I Need the Right Tools

[Chips O'Toole]

I just bought a Gorton 375 grinder. Paid $1150 including shipping, and now I find that the bearings are fried. I have to change them.

Problem: I don't know how to disassemble the spindle, and it clearly requires tools I don't have. There is a round arbor kind of a thing that looks like it will require a pin spanner of some kind. Then there is a little nut of some kind under it, which also takes a special tool. Finally, there is a big nut about 1.75" wide, which looks like it takes some kind of spanner with square pins.

Can someone give me ideas about what tools I need?

I don't know anything about the bearings. Haven't seen any numbers on the one bearing I can see.

 

[cathead]

Sure, I will be back shortly with some photos for you.

 

[cathead]

The top one is for holes around a cylindrical surface and the middle one is for on the face of a cylindrical surface. The bottom tool
is for grooves cut in the side of a cylinder. They are not real difficult to make, the top two being shop made and the bottom
one factory made. They don't get often used but very handy when needed.

 

[machPete99]

I don't know anything about the Gorton, but some info may be gleaned from here:

Riser's Gorton 375-2 Grinder

Someone recently posted a good video on spindle rebuilding, that gets into a lot of the workmanship stuff.

If your grinder is like the above diagrams it seems there is a double angular contact bearing at one end and a single at the other.
These bearings typically have some form of preloading that must be accomplished to take up all play, and there are different techniques that could be used.

The diagrams seem to show a spacer between the bearing outer shells, which might need to be shimmed to apply the preload.
Different bearings may require different shims. With duplex matched bearings (like bridgeport) there is usually an inside and outside spacer that need to be the exact same length (within tenths).

Some other spindle setups use an adjustable spring loading system, like the Dumore I am currently rebuilding.

 

[Chips O'Toole]

Thanks for all the help.

Regarding spanners, I have a set of hook spanners, but that's about it. The big nut will require some kind of spanner with square pins, and they are not easy to find. I came across a new Facom for around $180. I'm not ready to blow that kind of cash yet.

Tonight I made a spanner and tried to move the large nut, but the spanner broke before the nut gave in, so I'm back to square one.

As for the Riser diagram, I got all excited when I saw it, but then I realized the grinder spindle is not the same as mine. For one thing, I don't have an oiler. I assume my bearings are permanently lubricated. My spindle looks heavier than the one in the Riser picture.

I don't know which part has to be removed first. I don't know how to remove it. I don't know what kind of bearings I need.

I'm wondering if I need a bearing puller to get the back part of the wheel arbor off.

I feel like sending this thing back, but I don't know what my options are with Ebay. If I had the correct parts diagram and some help from someone who had actually disassembled one of these, I would have a fighting chance.

 

[gerritv]

I suggest you start by taking the wheel hub off the spindle first. Insert a correct sized bolt into the end of hub, tighten it up and the hub should pop off. That hub is keyed to the shaft, it should never turn.

Did you get a parts breakdown yet, because without that you are flying blind. e.g. The odds are very high that the big nut your are trying to remove is left-hand thread. The spindle is the heart and key to the machine doing good grinds so treat it nicely
Manual is available/was available from https://famcomachine.com/gorton-lars-cutter-grinders-pantographs/. They might have some parts as well.

You will also want to investigate this statement "This machine's "native" collet type is the now rather rare Rivett No. 4, New Style (i.e., "4NS") collets . " to see what collet type you need, assuming it didn't come with any.

 

[Chips O'Toole]

There is no internal thread on either end of the spindle, so inserting a bolt is not possible. I think the arbor part needs a bearing puller, so I ordered one. Maybe after I remove the arbor's back half, I'll be able to get the nut out with a spanner, which I also had to order. Finding an adjustable spanner with square pins for a reasonable price is surprisingly hard.

 

[gerritv]

On the second photo you posted, there are 2 threads on lh side. the smaller diameter one is the spindle shaft, it had a nut to hold the wheel hub in place. The next thread is for the 'nut' that held the wheel onto the hub itself. On the inside of that hub, are you sure there are no threads? The hubs usually have a taper, on Deckel it is only 1 or 2° so it will stick.

 

[Chips O'Toole]

It doesn't appear to be threaded, but it's not possible to be sure.

I found an Ebay listing for a similar arbor, all by itself, and the blurry photos don't seem to show threads.

The keyseat suggests to me that there are no threads. I haven't seen a key, so I wonder what the keyseat is for. I don't think I knocked one out on the shop floor.

Once the puller gets here, I'll find out what holds the arbor on. If it doesn't pop off easily, it must be threaded.

 

[gerritv]

Would you happen to have a photo of the assembly with a grinding wheel still on it, or did the machine arrive this way? That key way is to keep a washer from turning, the washer being between the grinding wheel and the large diameter nut holding it onto the hub. The intent is that you mount a wheel on a hub, then swap hub and wheel together, thus keeping concentricity and balance intact.

If there are no threads inside that hub end then it could well be a straight shaft (my Alexander 2CG is straight shaft as are older Deckel SO's).

The puller will do the job and all will be revealed