Here is a list of all the postings Neil Greenaway has made in our forums. Click on a thread name to jump to the thread.
|Thread: harrison m300, spindle run out...bearings?|
|This is a topic that's really caught my interest!|
Could you change the headstock oil....even flush with kerosene or red diesel to remove as much of the contamination as possible. Dry then new oil.....maybe a 68 grade hydraulic oil.
That middle od you clocked is on a sliding gear isn't it so will be subject to tolerance accumulations....even a sliver of the bronze washed inside the splined I/d could give you the eccentricity, and the slight cyclical knock i think you mentioned and even generate friction and heat when running cyclically in contact with the mating gears.
If it were me I would make up a pin wrench....maybe some pipe and a roll pin and a bit of welding and tighten up that ring nut you had your hands on in the last 3 videos. Loosen the socket screw and adjust per the manual. The bearing might actually be ok.....can you do any further damage if it isn't. Even if you were able to flush into the splines in the sliding back gear you might clean out some particles.....maybe a tin of aerosol brake cleaner as it has a bit of force with the spray.
Just some ideas....not necessarily ideal if you are seeking 100% perfection but easy low cost practical ideas that might get you going until you decide if new bearings are needed?
Edited By Neil Greenaway on 19/12/2018 21:51:14
Edited By Neil Greenaway on 19/12/2018 21:52:44
|Wondered if the symptoms here have any similarities?|
What sort of bearings are fitted in the rear end of the headstock - cylindrical roller bearings, needle roller or is it another taper roller bearing? If its a taper roller bearing and the rollers are appearing to not be pre-loaded then this can be rectified with whatever adjustment is provided- if they are cylindrical roller bearings or needle rollers and the rollers are moving in the cage then perhaps this is indicating wear. If you had a headstock cross section drawing you could upload a photo of this might help everybody with the diagnosis advice.
|Another thought.....I think the m390 series had an external oil pump driven inside the changewheel/belt guard. Does the m300 use this forced oil circulation.....if so is it circulating oil as designed or maybe it's just using splash lubrication up to the bearings and causes.|
Don't suppose you took any photos while you had the cover off and headstock opened?did you notice if there was a pair of preload adjustment ring nuts on the back side of the inner race of the front taper roller bearing? When adjusted correctly you may also have similar adjustment on a pair of deep groove angular contact bearings on the rear end which would also need fine tuning.i am wondering if the preload were slightly out could this cause heat generation.i would doubt if there is bearing eccentricity adjustment.....they normally seat in a machined shouldered bore in the front end with the inner race fitting in on the shaft from tailstock to headstock fitting direction and the various preloads being adjusted. My memory is a bit woolly on the exact details however and trying to put recollections into words! Do you have a manual with assembly general arrangement drawings etc?
One of your concerns as mentioned relates to a potential fall or impact in the past.....I could see features such as the carriage and handwheels being damaged......but the spindle is well in board of the outline so just wondering what spindle or bearing damage likelihood is potentially going to be?
If you pre-load the spindle bearings artificially with the tailstock by applying a thrust load with a revolving centre towards the headstock do you experience any movement? I remember this was the case with my spindle and when you force the tapered roller bearings together you can eliminate the "slop". Might be worth a quick check before investing in any purchased parts such as belts etc - although of course belts sitting in one position for a time can take on a "set". If the rubber isn't dozed they may still be OK when warmed up a bit.
I am not sure how similar the M300 is to the previous L5 series. I have an L5, and remember some years ago having some symptoms similar to those you mention - it turned out that the pre-load on the headstock bearings was not set correctly. In fact the lock nuts (plain OD ring nuts with pin holes on the OD face) had not been locked together and had backed off perhaps through vibration of bad cuts and chattering - hence the situation worsened. I was able to remove the top cover from the headstock (2 caphead screws) and adjust the pre-load and lock the nuts. From memory this solved the issue. Perhaps you have something like this occurring?
|Thread: Quick release hook|
Could you use a chain shortener clutch hook of a suitable size which could be attached to a chain link and possible release itself using gravity - these are normally sized for standard lifting chain. The pin end could be fitted with a loose lift chain.
|Thread: Coolant pipe seals|
I take it the gland nut butts against the steel shoulder and then the brass insert fits into the elbow bore? I have seen some connections like this with a gland nut having an o-ring on the groove at the steel/brass joint area and a plastic (normally PEEK) back-up ring to allow actual tightening of the joint and compresion of the o-ring whilst allowing flexibility in the joint. The back-up rings would be a plastic ring with a split to allow it to be pusted on to an oversize OD and then set inside a groove - would be easy to turn from some durable plastic and then form a scarf joint with a sharp knife blade. Make a pair of backup rings and use an o-ring that will crease a good sealing fit on the OD of the pipe and the bore of the elbow I hope this makes sense?
|Thread: Lathe bearing oiler wicks/felt|
try https://hardy-hanson.co.uk/ - they appear to have a range of different industrial felts including wicking rope types.
|Thread: Power Hacksaw|
I have a rapidor and it cuts on the forward stroke. At the end of the forward cutting stroke the saw frame will have risen to the top of an incline, and the dashpot oil/piston will hold the saw frame in a slightly elevated position during the return stroke (provided the oil bleed is set correctly on the dashpot. By the time the saw frame has returned to the start of the cutting stroke, the frame should have lowered itself ready for the next cutting stroke. The axis of the slide bars is at a slightly different angle than the axis of the blade from memory in order to give the correct geometry for the incline during cutting and holding the blade off the cut surface during the return stroke.
I hope this makes sense.
|Thread: Leaking shed flue plate|
A Decktite flashing would be the best option as it is rated for high temperature use, and can be fastened to both the flue and the roof - it uses a flexible silicone rubber boot which takes up expansion and could be screwed tight down onto the roof.
Might be worth a try..
|Thread: Vertical Shear Lathe Tooling|
I think the round toolbit you are talking about was described by LC Mason in "using the small lathe" book.
|Thread: Nemet - Lynx|
I remembered there was an article some time ago as a work colleague was interested in this area of coil winding - turns out a lego machine was designed and article published in Autumn 2011 issue, but with a view to using this as a prototype for a more commercial version - perhaps this might be useful for an update on what happened - did it go commercial?
|Thread: Need contacts with high speed lathes (to make a firing pin)|
Have you contacted any gunsmiths to source a suitable manufacture - some have machine shops and would be very capable of manufacturing such an item - and to add to it they would be in a better position to maintain the legal aspects in the correct order. I believe Hollow farm guns in Northern Ireland have done work of this nature in the past. Even if your local gun shop does not have a machine shop of their own they may be able to have a pin manufactured very ligitimately with less queries?
|Thread: Earth fault on lathe|
Got time to test things yesterday and found a few faults or so I thought! Ranged from continuity between 2 phases making me think that the main supply cable was faulty to a voltage reading between neutral and earth before tripping of about 150v! I narrowed it down after eliminating all other faults to the 415v to 110v transformer. Upon removal it was open circuit on the 415v tapping on primary side. Testing on 240v test block resilted in a small puff of smoke and the open circuit. New transformer needed. Lathe tested by manually pulling in the contactors and mo tripping observed with thr transformer removed. Still need to check the contactor coils are ok as cant get at them but fingers crossed after I replace the transformer.
I have a Harrison M390 which has just started causing problems - tripping out the 3ph RCD on the generator we run it on - At first I thought it was dampness allowing earth leakage from some other electronic circuits also connected in the workshop (DRO's etc) so we ran a small heater to dry out the panels just in case - this has helped a little and allows it to run a little longer before tripping. I think the 110v supply might be part of the problem - it supplied the safety circuit and the brake caliper solenoid. The problem also started last week after a heavy downpour of rain - bit of a mystery but just need to get time to properly look into it.
|Thread: Need to make a spring|
Is there any chance that a 2 stroke engine recoil spring could be adapted to provide return action? They are easy to obtain from garden machine service agents and not too expensive at just a few quid! Look at one from a small strimmer or chainsaw engine.
|Thread: Noise Insulation/Suppression|
Rockwool or saint gobain isover also make varieties of sound insulation materials which could be used inside a plywood wall sandwich. This is available from local building merchants.
|Thread: Universal Grinding machine construction series?|
I would be interested to read this article however only subscribe to MEW - if you look at the title of MEW I would have thought it would be better suited to a workshop magazine. I do find it difficult recently to see what direction MEW is heading in for the future? My interests are more around workshop machinery but still enjoyed learning about other machines (clocks, steam, stirling etc) as it was another wing of my engineering career and hobby so to speak!
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