Afternoon guys,I finish installing all my oil embedded sleeves into QCGB.But they are just a tad to tight,I can push in the shaft but its just little tight to turn.The shaft is 3/4 and the bushing just slightly smaller so I was wondering if I can take a steel 3/4 ball and drive it through the bushing just to open it up ever so slightly.I know that this will seal the bushing but it does have an oil port.Will this work or how does a person open the ID just enough to where the shaft will have little room?
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Sizing Bushing w/Steel Ball
- Thread starter Kroll
- Start date
- Joined
- Jul 2, 2014
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- 7,594
A sharp tool, like a new reamer. The ball will ruin the bushing for supplying oil to the shaft.
When building a whipstock every run required new bushings for the rollers, 30-40 per whipstock. We would get the bushings close and push them in the rollers and then run a sizing pin through the roller. We could hold tight and consistent tolerances and the .001 or .002 sizing didn't seem to affect the performance of the oilite bushings. Some rollers had to be less than a thousands clearance and some rollers required greater clearances. We had sizing pins for both types of rollers
What is a sizing pin,maybe if you could provide a link to one?Bob I do have a 3/4 reamer but since its my QCGB I have no way of telling if I am straight in line with the bushing or kinda at an angle.I tried making a dry run but I just wanted to see if there is another way
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4GSR
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Install the shaft without the guts of the gear box. Next, take a brass or aluminum round or square bar about 6" long. Place bar on shaft next to bearing and give it a good blow from a 16 oz ball peen hammer. Do it at 90 degrees from first blow. Do like wise at other end of shaft, too. That should seat the shaft and let the shaft turn a little better.
Our sizing pins had a lead in section that would slide in the bushing to start it straight then tapered up to a size determined to expand the bushing for the proper clearance. So if you had a shaft that measured .750 and needed .001 - .0015 clearance you wold make your lead in about .749 or .748 then taper up to about .751-.7515 PLUS the spring back on the bushing. Oilite bushings spring back about a half thousands I think. We made sizing pins for standard brass bushings too but they have little spring back and don't take to compression as easily as oilite bushings. This type of fitment is mentioned on oilite bushing paperwork, maybe not as we did it but it worked for us.
I forgot this part. The pin would be pressed through the installed bushing and size the internal dimension much like you idea of pushing a 3/4 ball through the bushing. The ball would probably work but by using a pin the bore would be really uniform. Once you get the dimensions figured out you can hold really tight tolerances every time.
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cg285
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start at 2:50. this is for valve guides but the procedure is same. if the id needed is exactly .750 then you would need a ball about .751-.7515
you could make one like bto mentioned - just be careful as too great a dimension"change" may crack the boss/housing. ie: if your bushing id is say .740 that would be way too much to ball broach
since you can install the shaft that would not be the case