RE: [multimachine] Re: New spindle drawing needed/car expert needed
Very informative post, Örjan. Thank you.
Jack, here you have some links on gingery type headstock boring.
here is a video
I know this can be done between centres with some slight changes.
for one you would need to have a tailstock with a centre (needs to be as centred as you can get it, that is points meet as well as you can manage, like this
> <both from above and in height above the bed, otherwise the hole will be slightly oval.
the boring bar sit something like this between the centres, the " | " is the toolbit.
>==|==<a temporary tailstock could likely be made from hardwood.
drive it can be as simple as a lathe dog to drive the bar OR even a pulley directly on the bar close to one end,I think wood would be fine for the pulley as 200RPM would be about maximum speed you would want even for a 20mm bore.
of dead centres are used (pieces of almost any hard metal with conical points would do) oil them well and let centres rest when they get too hot to touch comfortably with back of hand, same with live centres by the way.
PLEASE! STOP MACHINE BEFORE YOU MEASURE/TEST/ADJUST ANYTHING!
just remembered, one would need to have the set screw for the toolbit from the side instead of from the front.
scaling this up/down would be a question of available power and speeds, larger bore would mean lower speed for the rotating bit and more power, or less material removed each cut also lower feed to keep forces within reason.
I frequently use paper and a "gingery depthing tool" to set boringbars for rough cuts, place a slip of paper between screw and toolbit at current setting, loosen set screw, remove paper and advance the toolbit, tighten set screw you now have ~0.12mm (most printer paper is 0.1-0,14mm) depth of cut, cigarette paper is 0.04-0.02mm and OK for near finishing cuts.
below is a link to an image of the tool I use when setting cutting depth, just remember that hole will be twice cutting depth larger in diameter.
they both come from bottom of this page
I have a store bought micrometer tool but I still have two of these around when i do not need extreme precision (it is a large diametre vernier screw micrometer, it reads to 0.001mm).
I also have a similar tool that fit my lathe collet-bore (WW-12) that allow me to perfectly set toolbits in my watchmaker lathe toolholder.
here is a video showing the gingery 2jaw "chuck" which should be possible to fabricate from many different materials, if used for small short work "less than 25mm sticking out and preferably more than 1/2 inside the chuck) and at low speed possibly even hardwood would work for the jaws.
I think Gingery's method, boring out the headstock using the bed to guide it is is very sound mechanical practice.
By keeping the boringbar stationary moving the headstock, one can be fairly certain that bearing-bores in the headstock align to the bed and share both axis. Then by using the new headstock to bore the permanent tailstock in similar fashion, you assure the centre axis of both the head and tail stock are exactly same hight and true to the bed.
hope I gave you some ideas for solutions.
--- In email@example.com, jacot <jacquessavard@...> wrote:
> <i try to built one whit my radial sawa photocopier motor whit gear set on vey slow
> I have a drill chuck on one side and a polley on the other side drive whit
> But no real schuck
> Jack 47â€™N 71â€™MW
- I agree also!Homebuilt tools are for those who have no money but do have access to scrap. Other people should look for used tools but should realize that totally accurate rebuilds are very difficult.Don't let rust scare you off unless the machine was totally worn out before it was put out to pasture.Pat
From: David Lee <dsleei@...>
Sent: Thursday, August 8, 2013 2:15 PM
Subject: RE: [multimachine] Basic functioning mill/drill
Excellent advice.DSLeeBoth options have pros and cons,much of the success will depend on the details.IMO:1- buy an old american cast iron 9 or 10" latheand rebuild it. Works great, but not for slotting,even with the "milling" attachment. Est cost $500-900< forget the HF lathe, poor quality for more thanmodel maker sized projects>.2- Buy an old american made cast iron horizontal mill andrebuild it. Est $500-700. Works great for slotting and drilling,lathe work is very limited in size due to the table size / movement.3- Buy one of each. Est $1000. Excellent idea. Con[ space needed.4a- Build a smaller scale multimachine using a motorcycle or lawnmowerengine. Est $200-500 depended on your "junkpile".Pro, cheaper, make it to the size you need / have.Con: time to build, may not look "pretty".4b- look in the photo files for the home-built mill project.Uses a concrete frame and head. Smallish.5- Build a multi axis lathe ala the Concrete lathe with anoverhead arm for the 3rd axis. Con: more complicated build,more $$, more space.Pro: more versatile, more flexible use, greater "cool" factor.lance+++++On Aug 8, 2013, at 12:07 PM, Alan Nauman wrote:
Should I just purchase a lower cost s mall drill/mill/lathe and fight the size limits that come with it or is it reasonable for me to build a Multimachine that would perform limited functions that are not super accurate at a low cost?