Here is a list of all the postings Matthew Davenhill has made in our forums. Click on a thread name to jump to the thread.
|Thread: Clarkson Auto lock - 3 ish questions!!|
Gents thanks for the advice, this far I’ve created two albums and added one photo! However it won’t do anymore, not sure why!
Just a couple of more photos of the large chuck
I was given an old clarkson autolock MT3 that has stamped on the side of it type c c’. it came with the below
the collets with nibs on are type c, can anyone tell me what the half crescent Collets are?
i think this is what’s classed as miniature chuck; however I didn’t know they did them with c collets? Am I correct in my assumption?
now on to the 3rd is question.
I’m waiting for the below to be delivered, very reasonable price. It has no collets and is described as very large, I think it’s a large autolock S. Can anyone confirm and will it take all S collets,
|Thread: Bridgeport quill feed gear box|
Not sure if that makes sense, I can try and get some close ups
I’m rebuilding a 2J head Bridgeport, I’m re assembling the quill feed gear box, each gear is held in place by a brass bearing and two set screws. When I tighten the set screws to nipping up level of tight( any of them) the gear box seizes up. Has anyone else come across this?
It is worth noting the gears seem to tighten ever so slightly at certain positions normally.
|Thread: Assessing machine wear|
A straightt forward question I hope! I’m stripping a Bridgeport and it’s seen a shift or two! On each of the machines ways there seems to be what I assume are machined datum surfaces either side of the dove tail. So for the question ! How do I assess the wear and what kit do I need?
Some indication of wear, can see some remnants of scraping on the rear slide, thanks for the advice both.
David- I think I have a copy in pdf format, also have the lion industries book. Don’t really want to scrap it, more because I’m not sure where to start!
I’m in the process of stripping and cleaning a Bridgeport j2, all works but showing a fair amount of wear. Other than scrapping or re scraping the ways, any advice on working with worn machines?
|Thread: Tool grinding|
looking at buying a new grinder, has any one found a better way of doing it that a traditional two wheel grinder? I.e. Something like this. http://www.screwfix.com/p/scheppach-tiger2000s-200mm-whetstone-sharpening-honing-machine-230v/40540
In addition has anyone found a rest that you can set the angle on for sale, I know there are lots of DIY designs out there, or found a bench grinder with a system or the angle already marked?
|Thread: 3 jaw chuck run out after machining|
Tipped tool ,about 3 thou cut an inch from the chuck
This is the reading on the freshly machines surface, any thoughts on the cause? The mounting surfaces are clean.
I'm in the process of commissioning my lathe, when I place a dti on a machined length of bright bar which has been turned in a 3 jaw, I get around 0.02mm run out on the machined surface. Does this sound acceptable?
Edited By Matthew Davenhill on 30/05/2017 19:38:30
|Thread: Accuracy of an old machine|
Thanks for the input, it turns out a gasket I had installed on the saddle was too thick and was removing clearance out of the leadscrew, it was slightly rubbing the lead screw and causing it to lift the saddle and alter the cut
I've checked headstock play in accordance with the Lang manual, initially I put a piece of bar in the chuck and used a length of wood against the ways to lift; however, Lang recommend an end load test of 200lbs from which you determine play with a DTI. I've don't this and it shows 1 thou which is within the tollerence allowed by Lang.
Thanks for the advice thus far, in response to one of the comments, I have the manual from lathes.co.uk. I've done a little more work, unsupported the machine cuts parallel for around 75mm but the suddenly cuts a .05mm taper towards the headstock over the remaining 75mm. (I.e. The dia of the work piece reduces) I did wonder about bed wear but surely it would do the opposite? It has been mentioned that the headstock could be out of alignment, I'm a little sceptical my self. I've put a new gasket between the saddle and the carriage, I did wonder if that could be causing issues. Any thoughts ??
To test for play in the bearings it states the following in the below photo, any idea where I can get a 200lb spring
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