|Paul M||09/07/2020 15:43:25|
|42 forum posts|
I am building a 31/2" Lifford Hall loco. I fear I have somehow managed to get one of the driving wheels running out of true. I machined the axles between centres and used loctite to secure the wheel. There now appears to be about 14thou sideways (lateral) movement on wheel at the outer edge. The tread is concentric to the axle. I fear I may have not gone through square with the reamer as I did suspect a bit of lateral movement before loctiting but assumed it was the clearance between the wheel and axle prior to fixing.
What puzzles me is that I used a jig set in lathe to machine each wheel.
I really don't want to start another wheel so am looking for suggestions/advice on the way forward. My initial thought was to drill out the axle and somehow set the wheel up and bore out a few thou remake the axle and hope.
Things were going well up to this point!!
18329 forum posts
For an accurate fit I always prefer to bore as you can size the hole to whatever needs to fit with a loctite joint having a smaller hole than say one in a bearing.
Drilling then reaming particularly into a casting is also prone to problems as any hard spots, voids, etc in the casting will cause the drill to wander and then the reamer will just follow the path of the drilled hole.
You could possibly bore out the wheel and loctite in a piece of bar and then bore that out to fit your existing axle.
|Paul M||09/07/2020 16:15:11|
|42 forum posts|
I appreciate your advice. I have realised too late the possible problems with drilling and reaming especially into cast iron.
|Phil H1||09/07/2020 17:07:46|
|292 forum posts|
Unfortunately, It feels like deja vu. I had almost exactly the same snag with one of my Rob Roy wheels. I ended up cutting the axle and reboring on a face plate. I also had to make a wheel quartering fixture because I fouled up the quartering on the lathe.
As Jason has explained, I suspect reamers can sometimes follow the drill and produce a wobble on locomotive wheels and other similar parts.
|410 forum posts|
A reamer will always follow a drilled hole, best way for things that matter is to drill, bore and then ream.
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