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I would first make sure shaft is good.
If needed make a repair sleeve that slips over shaft, there are shaft repair sleeves available for this to repair where seals go.
Oce that is done then determine how to hold this in a mill and with a boring bar open up the hole until it is round.
With the boring head you can open up the diameter to allow it to work like a fly cutter, you can then use it to touch off the top of the casting to make the top flat and square with the bore.
Last, make a bushing that fits repaired shaft and new round hole, insuring it has a larger top hat on it that rests on the flat surface you made.
Mounting can be epoxy in place, use good epoxy and done.
Bushing can be replaced as needed.
You can add a zerk to allow greasing it or oil cup, that is up to you.
Sent from my SM-G781V using Tapatalk
If needed make a repair sleeve that slips over shaft, there are shaft repair sleeves available for this to repair where seals go.
Oce that is done then determine how to hold this in a mill and with a boring bar open up the hole until it is round.
With the boring head you can open up the diameter to allow it to work like a fly cutter, you can then use it to touch off the top of the casting to make the top flat and square with the bore.
Last, make a bushing that fits repaired shaft and new round hole, insuring it has a larger top hat on it that rests on the flat surface you made.
Mounting can be epoxy in place, use good epoxy and done.
Bushing can be replaced as needed.
You can add a zerk to allow greasing it or oil cup, that is up to you.
Sent from my SM-G781V using Tapatalk
Thank you for the detailed reply. Yes, both the feed rod and the gear shaft it drives are in good shape.
However the wear in the shoe is not uniform. It is definitely oblong, to each side along a line. I like the idea about grinding a surface to use as a mounting surface.
A boring bar can be used to scribe the area to be cut. My primary concerns are centering the part and squaring the top and bottom holes to be bored. Once that is done the boring can be done carefully.
Any additionall thoughts, concerns, or cautions. Dan
However the wear in the shoe is not uniform. It is definitely oblong, to each side along a line. I like the idea about grinding a surface to use as a mounting surface.
A boring bar can be used to scribe the area to be cut. My primary concerns are centering the part and squaring the top and bottom holes to be bored. Once that is done the boring can be done carefully.
Any additionall thoughts, concerns, or cautions. Dan
Update: Plan for alignment.
Let's assume the plan is to move forward with the mill and the boring bar. The problem with that is aligning and clamping the 'shoe' so the boring process is centered and square. My thought is to hold a 3/4 inch rod in place in the shoe with shims and then hold the end of the rod in place in the mill while the shoe is firmly clamped to the base of the mill. This will allow the mill bed to be lowered and the boring bar to be installed in the mill. The result should be the shoe centered and the shoe is firmly clamped to the bed. The shims will allow for some adjustment of the 3/4 inch rod in the elongated hole for the best fit.
Are there issues with this? Is there a better way? Thanks in advance. Dan
Let's assume the plan is to move forward with the mill and the boring bar. The problem with that is aligning and clamping the 'shoe' so the boring process is centered and square. My thought is to hold a 3/4 inch rod in place in the shoe with shims and then hold the end of the rod in place in the mill while the shoe is firmly clamped to the base of the mill. This will allow the mill bed to be lowered and the boring bar to be installed in the mill. The result should be the shoe centered and the shoe is firmly clamped to the bed. The shims will allow for some adjustment of the 3/4 inch rod in the elongated hole for the best fit.
Are there issues with this? Is there a better way? Thanks in advance. Dan
I don't have a good answer, but since you mentioned welding, cast iron will very likely to need preheat and slow cool down (with cat litter or high temp blanket) if you're not already aware of it. Good luck.
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- Nov 24, 2014
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@dansawyer
Following is my concept for how to best establish the correct location/orientation for the bore.
First, early on, you mentioned that the feed rod had some sort of burr (or lip) at the keyway slot. I presume you've removed that anomaly.
Next I would machine two thick (.25"-.50") washers with an ID that fits the OD of the feed rod very closely.
Then reassemble the lathe with the addition of a thick washer, loose, at each end of the 'shoe'.
Move the carriage very close to head stock and check the unsupported portion of the feed rod for droop. Support as required to make the rod straight.
Bond the thick washer (at the headstock end) to the 'shoe' using a five minute epoxy (brittle and easy to remove) and allow to fully cure.
Move the carriage to the opposite extreme (tailstock end) of travel an bond the other thick washer to the 'shoe'.
Having those two precision IDs fixed the 'shoe' should allow you to orient, clamp and machine the part in a way that will not cause binding or excessive wear when the repair is completed.
If the configuration of your lathe allows access to only one end of the 'shoe', use a single tube, rather than a pair of washers.
Following is my concept for how to best establish the correct location/orientation for the bore.
First, early on, you mentioned that the feed rod had some sort of burr (or lip) at the keyway slot. I presume you've removed that anomaly.
Next I would machine two thick (.25"-.50") washers with an ID that fits the OD of the feed rod very closely.
Then reassemble the lathe with the addition of a thick washer, loose, at each end of the 'shoe'.
Move the carriage very close to head stock and check the unsupported portion of the feed rod for droop. Support as required to make the rod straight.
Bond the thick washer (at the headstock end) to the 'shoe' using a five minute epoxy (brittle and easy to remove) and allow to fully cure.
Move the carriage to the opposite extreme (tailstock end) of travel an bond the other thick washer to the 'shoe'.
Having those two precision IDs fixed the 'shoe' should allow you to orient, clamp and machine the part in a way that will not cause binding or excessive wear when the repair is completed.
If the configuration of your lathe allows access to only one end of the 'shoe', use a single tube, rather than a pair of washers.
This all day long!
Thank you. I will give this a try and let you know.
