Dodgy Feed Handle Repair on a Lathe
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- Опубліковано 12 лип 2020
- While beginning to commission the feed gearbox and apron, it was clear the feed handle on the apron was dody - simple repair job once it came apart. Mostly hand tools and a bit of shaper work.
Bricks in front of your wheelbarrow is an expression that comes to mind!.
Lathe looking good.
Thanks for sharing, regards John.
Pot holes for sure John.
Mat
You have endless patience Matt!
ATB, Robin
I am sure you confuse patience with me working very sloooooooow :-) Admittedly, I have to edit out the cursing when it doesnt go to plan - but we all do that dont we :-) Great to see you commenting on the vids again Robin - take care and enjoy your weekend. All the best Mat
Nice work. Always good to see a successful repair.
Stay tuned theres bound to be a not so good repair along soon ! Alll the best Mat
The lathe is looking great. I can only imagine how many times that apron traversed to wear that key down like that. Thanks as always for sharing your craftsmanship!
Thanks for watching Russ. All the best Mat
Hi Matt. Good to see some traditional hand fitting. Just a suggestion: if you raise your vice, so that the top of the jaws touch the bottom of your elbow when you hold it horizontal, your cutting and filing height will be optimal. All the vices in my toolmaking training centre are adjustable in height, to suit the different apprentices for this reason. As always, thanks for the great content!
Its not far off, I do hope to get a suitable work bench installed in the workshop once Ive got the lathe running. As it is the vice is G Clamped to the bandsaw table ! - far from ideal. Thanks for the info' I shall have a look it I can add a spacer. Mat
Hi Mat,
Always good to see hand fitting...
Cheers
Paul,,
oddly satisfying i find. Slower to cock it up as well :-)
Nice repair. And bonus points for thinking about the next time it needs replacing by adding the 4mm jacking point. Spending a few minutes adding that will save a lot of time if you, or more likely the next custodian of the lathe a lot of bother...
I doubt it will wear out anytime soon - and I doubt that anyone will take it on after me. Who knows. Cheers Paul. ATB Mat
@@lookcreations If anyone does take it on after you, and would hope someone does, then they'll be getting it in working order and not bodged together. Plus they'll have access to all these videos to see how it goes together :)
I’m sure if you added up your time at a machinists rate this would be a $20k lathe, which makes no sense, but since it is your own machine for fun who cares. And you are saving a fine old machine. Great to watch how you do it. I have several machines waiting in the que for just this treatment.
The saying when this lathe was in serious use, "The Colchester Lathes on the shop floor, cost as much as the bosses car, the Holbrook in the Toolroom as much as his House." I very much suspect if I priced my hourly rate at anything approaching a 'fitters rate' this lathe would be getting rather pricey ! On the other hand, I know folk that have paid out £3k to get a basic introduction to machine tool rebuilding and scraping - I would say, I've learned a good deal more doing the lathe than attending a a years worth of similar courses. I hope I've passed some of those lessons on. This was never about just 'getting the lathe running' or making it 'ex factory condition' - It was mainly about learning how to rebuild a lathe / machine to a high standard and understanding whats involved. All the time developing as many new skills as I could along the way. Hopefuly when Im done I will have a good lathe to undertake work with.
I do wonder what the costs of attending some course / apprenticeship to learn the same would cost today ?
What do you think ? Mat
lookcreations I took Richard King’s 1 week scraping class. It was I think $1800 for a week. It was enough to get started. I don’t have your technical experience so taking in such a project starting from nothing was just too daunting. Certainly 1 week is not enough to learn everything you need but it was a great introduction and I would start small, like the topslide, and work my way up to the bed. Even if one took a longer more in depth course, eventually one has to actually do the work, put in the hours. But that course I took gave me the confidence to get started. I guess with your work experience you already had that.
Nice fix there Matt. Fit right in there like the original, nice hand work!
Here's the thing, I recorded all the hand file work, but man is filing boring to watch so it mostly got cut out, besides most guys would have cut it on a mill Im sure. Glad you enjoyed and thanks for stopping by. Another vid uploading tonight. Mat
Lots of traverse time on that handle to wear that key like that. The clutch handle on my big Moarch is similarly slack and could use some love as well. For now it works though so I avoid working on it. LOL
This worked but it was next to imposible to set the link pin to activate the yoke on the dog clutch. Difficult to describe Brian, but the activation link is 'clamped' on to the shaft end, its absolute position needs to be set with the feed handle in position, clutch engaged in the correct position for the feed and then locked / tightened. I found a 0.020" out was rendering it not reliable. .020" movement of the rack on the end of the shaft was nothing compared to the loss from the wear. It was probably fine 'worn in' but once the position was released the erros started to creep in and the feed couldnt be repeatably engaged.
Thanks for sharing!
Thanks for watching!
The key only ever sees the weight of the handle while sliding and very occasionally the operating force when stopped (or stopping) so the asymmetric wear is explicable.
Nice to see someone using a hacksaw rather than an angel grindr for a change.
Anything to keep th enoise down and increase control. Cheers Andy
Nice work, and I thought the keys on my lathe looked bad
When I first inspected it - I was sure it was cut like that ! My own dumb fault for not researching a bit further.
@@lookcreations At least it is fixed now, my lathe had a bad key on the worm drive of the feed screw into the saddle, it looked like an hourglass, but to replace that you have to tear the whole thing apart..
@@nightraidone9768 Its always a tricky call - on the other hand, you do know it will fail final pass on a really nice project !
Personally I don't agree with the person below who thinks that wasn't the original method used by Holbrook. That key fits the recess far too well and is radiused flush with it's mating part. Screws halfway into both parts is a fairly common method of retaining parts. Without those screws the key would be free to move and start wearing out the recess it fit's into.The screw locations and head counter sinks are also done much too well for what usually passes for an emergency in house fix it fast and well enough to make the machine work. That's not impossible of course, just a bit unlikely given this lathes less than stellar past maintenance. As Andy Pugh has already mentioned the dovetail shape along that key is logical given the weight of the handle loading the key in one direction only, the key would keep rotating as the wear increases and that dovetail shape would be the end result. I agree though, it does look too even, but I sure can't think of a proper reason why the key would need to be thinned and shaped like that when the lathe was new. Today we'd probably use a spring loaded ball and 3 position detent on the handle boss to prevent the weight of the handle from constantly loading the key in one direction.
Very good planning to use those tapped taper pins for location on that casting Mat. Next or if you ever have to pull them again run a nut then a heavy washer onto the bolt first. Thread the bolt into the taper pin then tighten the nut down against the washer to pull the taper pin. :-) If that carriage moves as well as it seems to in the video you did a beautiful job scraping the bed and bottom of the carriage.
The three position detent would have been a nice addition. I shall have a think for a retro fit. I had thought of making the key externally mounted from the flange end and cutting a key way down the sleeve - what I did seamed the quickest simplest solution. It is a very snug fit down the slot - time will tell if it rocks and wears the slot. Mat
No goodbye !
Strange dovetail wear pattern on the key.
Probably caused by years of pressure on the key when moving the carriage.
thats all I could think off.
That method of using a tapped hole 'split' vertically so half is in the part, and half is in the mating part, is pretty common. Is there any trick that allows making a new part with threads that synchronize with the mating part? I haven't been able to dream up anything with even a remote chance of working.
I was wondering about going up a size - but I concluded that as the key is captive within the sleeve and its housing - it cant come out only 'rock' I mage it a good tight fit down through the slot not wedged so it shouldnt rock. Time will tell. Mat
It's starting to look suspiciously like a working lathe.
Does the dog clutch have stops to disengage automatically like the Hardinge or is it just a manual lever and when are you sending out the free cigars and brandy to your subscribers for the switching on party?
There are a pair of adjustable stops and micrometer stops which operate the dog clutch (as I understand it) - I hope to get on to commissionng all that very soon. Am looking at a venue to hire and relcoation of the lathe for the switch on chip making party ! Cigars, Brandy, Dancing Girls the whole lot :-) All the best Mat
Another nice job. A little surprised that that key way on the selector shaft wasn't pointed down? Where it is it can easily load with swarf even micro swarf and with the power of the feed carriage in use and on the hand wheel could easily clog and jam. At the very least wear. Is it possible to re index the selector shaft and handle to have the slot underneath? That is how I would set them up if possible.
Cheers
dazaspc good point. Are you sure it wasn’t incorrectly assembled at one time? Do you have a manual with an exploded view?
@@sblack48 The machines I set up/repaired I couldn't tell you and I don't have a manual for this machine. I was a CNC repair guy for 30 years the number of manual lathe rebuilds I have done you could count on one hand and not use a thumb. I frequently had to work without manuals or not the exactly correct ones. However after seeing the state of the old machine when it was received I would guess it may have had a few rush repairs on it over the years?
Cheers
The shaft went back on as it was removed - the taper pin which secures the bevel gear is inserted from top - i.e. it can be tapped in from above. If the shaft is positioned in another orientation you cant get access to the pin to seat it - too tight for any kind of clamp. We I took the lateh appart on site - I had to get the gearbox off with the gear/shaft still on it to get access to knock out the pin. I cant believe Holbrook designed it like that so I very much suspect the thing had been appart before and put back togther the only way possible at the time. I also believe that the fitters at Holbrook had some bespoke tools for assembly - tasks made easier with such - plus knowing the sequence of assembly ! All the best mat
I suspect it was.
Hiya
Interesting 2 set screws holding key, that can't be original. Nice idea screw through key to remove if needed.
Pretty sure thats normal Holbrook approach, similar to others on the lathe - concider also that the sleeve sits fully enclosed in its housing - the key cant come back out only down !
I have a similar issue on my hendey to deal with
Ive seen a few Hendy and other US made lathes show similar wear / droop. I shouldnt imagine the keys are much different. All the best Mat
@@lookcreations hopefully I will get around to fixing it someday. Kinda got new machine that's way more important. Lots of hours of video to take..lol