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View Full Version : Doing some work, need some advice



spkrman15
04-13-2003, 10:31 AM
My brother-in-law has asked me to make some pins and bushings for his loader. Cool finally some paying work. I think?

Anyways. I would like wo know what clearences are normal and/or allowed when making pins. 0.005? 0.003? The bushings will be welded in the bucket some there is most likely some warpage factor there. I don`t want to buy a reamer to re-cut the bushings but i was thinking of maybe honning them out a little if i found everything a little tight

Along the same subject. Any ideas on how to build a line boring tool for cutting out the old bushings?

Spkrman15

wierdscience
04-13-2003, 06:52 PM
I just did a big John Deere bucket last weekend.If you are going to weld the bushings in I suggest making the bushings.005-.010"oversize this seems to be the industry standard anyway.As far as alignment put the pin in the bushings and the bushings in the frame check it out with a tape measure and tack each bushing in four places then check for tight maybe have to knock around with a hammer and make sure that the pin still rotates then finish the weld.You can make the tolerence a little tighter and preheat the bushings before welding and get away with it but I don't recomend it.As for boring in place I had to do it last week and basicly what I did was weld up the eggshape and used a long bar through all four bushings this shaft was 1.5"crs ,I used this to position four 1.5"pillow blocks two on either side of a pair of ears,then I made a boring bar out of that same piece of shaft long enough to bore two bushings at a time and with the bar turnig free in the blocks I powered it with a 250rpm 3/4" electric drill and fed it slowly advancing the cutter no more than .015"per pass.I cut the two bushings out to 2.375"and then pressed sleeves to bush them down to the 50mm pin size.If I had the choice I would have burned the old bushings out and welded in new ones but the bushings in question were oval shaped to allow for a locking bolt to prevent rotation which is also something you will need to make sure of that the pin is held stationary in one set and allowed to rotate in the wear set,if you have any more questions feel free to ask.PS It took me 21 hours to build up and bore out the ones I did so be sure and charge him!

spkrman15
04-14-2003, 05:15 PM
I know i am going to kick myslef but can you describe a pillow block to me. I am drawing a blank. I know i will remember as soon as i see one or get it explaned

Sprkman

darryl
04-14-2003, 05:36 PM
A pillow block just about describes my head, from time to time. It's something that prevents the cleaning lady from removing the pillow case. Seriously, though, it's just a metal chunk that has a bearing, sleeve, ball, roller, or whatever, mounted in it, and some holes to mount it to an assembly of some kind. It usually allows for some misalignment of the bearings.

wierdscience
04-15-2003, 10:46 PM
Let me know how the job turns out.

Thrud
04-15-2003, 11:07 PM
spkrman15:
The bushing that hold the pin need little clearance - in fact clearance here only leads to hammering and distortion of the hole. The pin should haver a running clearance for grease on the pivot only. If you allow too much clearnce the grease will be extruded under pressure - if this happens go from a HD #2 NLGI grease with moly to a HD #4 NLGI grease with moly and it should stop this. If you let it go the grease gets squeezed out and the pins begin to gall. The pins are normally retained by straps, bolts, or large cotters. A 4130 case hardened pin should give good service. The piece that floats on the pin should have a good bore - reamed or ground - it should have a grease nipple too.

spkrman15
04-15-2003, 11:15 PM
well i have made the pins. That is a start. I am still wrestling with my plan for the bottom bushings. I want this to take the least amout of time as possible. AS well as the least amount of $$. I really like your idea with the pillow blocks and shafts. I will keep you posted

Spkrman15

Bob Quale
04-16-2003, 10:10 PM
I have an old JD and want to bore the holes for the pins that hold the Boom. They are egged and loose. Any idea as to how to bore these. I had a thread long ago about this.

Bob

gunbuilder
04-16-2003, 10:48 PM
<font face="Verdana, Arial" size="2">Originally posted by Bob Quale:
I have an old JD and want to bore the holes for the pins that hold the Boom. They are egged and loose. Any idea as to how to bore these. I had a thread long ago about this.

Bob</font>

Bob,
Are you talking about the holes in the boom or the frame?
If you are talking the frame, are there old bushings on the outside of the frame? If you can weld new bushings after removing the old ones that should be fairly easy. If you are talking on the boom between the frame clevises that would be much tougher.

Paul

Bob Quale
04-16-2003, 10:55 PM
Gun builder,

Yes, unfortunatly it is the part on the boom itself. The holes are egged. I wonder if i can buy a new casting for the bottom of the boom? I'm sure it would be REAL expensive!.

gunbuilder
04-17-2003, 11:08 AM
Bob,
I would think the best way is to use a smaller pin with new bushings on the boom. And modify the bucket with new bushings too.

I would use a CRS shaft to keep the boom bushings in alignment during welding. I would drill and tap the bushings for grease zerks.

If you are going to remove the old boom end castings you could bore them oversize and press new bushings in them. Then reweld the rebuilt ends back on the boom with the CRS shaft for alignment.

Yes, new parts from JD may be pricey, but you may be surprised, they may be less than you think if they are available at all.

What model loader is this? My Dad has a 158 Loader on a 4020 with Power Shift.

Paul

Bob Quale
04-17-2003, 07:28 PM
Gunbuilder

My backhoe is a 79 310A John deer. The bushings are the ones that hold the boom to the frame or swing arm. There is lots of meat in them so boring them should be do-able. The bottom casting is available at $1000.00. The removal and rewelding looks like more work than making a line bore and boring, and making bushings and pressing them in. I got a price for a guy to come out and line bore it. If it is all apart and I make and install the bushings it would be around $1100.00 just for the boring. Now I have to decide what path to take.

Thanks Bob

gunbuilder
04-17-2003, 10:38 PM
Bob,
I didn't realize it was a Backhoe boom. All my ideas were for loader arms.

Would a boring head on a mill work? The boom would need alot of support.

Paul