Robin Graham | 23/09/2019 00:10:26 |
1089 forum posts 345 photos | I'm bad at planning machining sequences. Sometimes if I want to make a thing involving new (to me) techniques I'll do the operations I know about, thinking "I'll cross that new bridge when I come to it". It doesn't always, or even often, work out well. This is a very simple project - a handle mounted on a taper, such as one often sees - eg: I turned the taper then thought how am I going to get the handle true? I've ended up like this: ie sticking the piece in the mill vice with a v-block and clocking the taper square. It'll work I'm sure, but it took ages to set the work and I have a nagging idea that I could have done better with more forethought. How would this normally be done on manual machines? Any more elegant ways of doing this? Robin.
Edited By Robin Graham on 23/09/2019 00:11:26 Edited By Robin Graham on 23/09/2019 00:15:11 Edited By Neil Wyatt on 23/09/2019 13:57:48 |
not done it yet | 23/09/2019 00:31:46 |
7517 forum posts 20 photos | Don’t often see one like that, that way up! It’s as good a way as any. Rough and ready might be a level sat on the bevel. An angle vise comes in handy for jobs such as that. But you just do it with what you have available, until your collection of holding options grows. |
Robin Graham | 23/09/2019 00:52:16 |
1089 forum posts 345 photos | Posted by not done it yet on 23/09/2019 00:31:46:
Don’t often see one like that, that way up! ... Just trying to be inclusive NDIY - there are antipodeans on this forum remember. Thanks for your opinion that my method wasn't insane - I'm self-taught mainly and worry about re-inventing wheels. Robin. |
David George 1 | 23/09/2019 06:19:48 |
![]() 2110 forum posts 565 photos | I have angle piece plates which you can put in the vice which set's the angle by pushing the the V block up to. IE 15 - 20 - 30 - 45 degrees it makes such jobs a bit more simple. David |
JasonB | 23/09/2019 07:05:05 |
![]() 25215 forum posts 3105 photos 1 articles | As you have a hole running through it the other way use that to bolt it to an angle plate or block of metal that can be set at an angle. Edited By JasonB on 23/09/2019 18:28:25 |
Brian G | 23/09/2019 08:34:34 |
912 forum posts 40 photos | I have zero trust in the nasty plastic protractor on a mini lathe, and always use a square or an angle gauge to set the compound. This would put me off using an angle plate or angle vice but I just realised that the same angle plate could be used to set the angle of the compound as well. David's method doesn't even require accurate angle plates, and I could make my own as long as I used the same one for both setups. To be honest though, if nobody was looking I would probably not have planned ahead and would have put a square against the end of the vice, then felt guilty that I didn't clock it as Robin has done. Regardless, all the methods on this thread so far look like less faffing around than tilting the head and re-tramming the mill afterwards. Brian |
Andrew Johnston | 23/09/2019 08:45:36 |
![]() 7061 forum posts 719 photos | Good grief, it all seems way over-complicated for a simple non-precision part. Techniques need to be appropriate for the level of precision needed. I made this as an exercise some years ago to prove a long forgotten point on the forum: It was made in less than 15 minutes using no measuring equipment, not even a rule. Everything was done by eye. Precision where precision is needed is good, but precision where it isn't needed is simply a waste of resource. Andrew |
Chris Evans 6 | 23/09/2019 08:58:25 |
![]() 2156 forum posts | Well put Andrew, I never chase thous unless it is required. Following on from Jasons method I regularly bolt two angle plates together to give the tilt required. |
Clive Foster | 23/09/2019 10:04:24 |
3630 forum posts 128 photos | Take a bit of time to set the mill bed (and drill table) level then you can use a half decent spirit level to set the job. I have a baby magnetic one that came with a plasma TV VESA mount which can be right handy on small parts. Not super accurate but good enuf for "needs to look right" jobs. Or just set a longer level behind as an eyeball reference and look across. Whilst you are at it arrange a couple of vertical / horizontal references on the wall behind the vice to eyeball across for quick straight up or straight across setting. My Bridgeport table ended up about 10 or 15 seconds of arc out of dead level when I dropped it in place. More by luck than judgement really but I did make an effort to get the shop floor level when I built the place. Nice smooth waterproof chipboard under flooring surface very, very close to level has proved handy at times when setting stuff up or making large things. Normal long builders level says its level! Clive |
Peter G. Shaw | 23/09/2019 10:13:39 |
![]() 1531 forum posts 44 photos | Horses for courses. Does it really matter how you do it, as long as the end result works. And I quite agree with Andrew, why waste time over measuring something that most people will only glance at before putting their hand on it. Cheers, Peter G. Shaw |
larry phelan 1 | 23/09/2019 13:02:53 |
1346 forum posts 15 photos | I think this is what other Members refer to as "Experience" ! Sad to say, I,m still slowly acquiring it . Long way to go ! This often results in some weird set-up.s, and I mean WEIRD ! But as long as it works, so what? |
Jim Butler 1 | 23/09/2019 13:18:07 |
17 forum posts 5 photos | Posted by Andrew Johnston on 23/09/2019 08:45:36:
. Precision where precision is needed is good, but precision where it isn't needed is simply a waste of resource.
Agreed, good enough is perfect. But for someone who is an amateur machinist, aiming for good precision when it is not really required is good practice for when it is required. I once made a couple of paxolin spacers for mounting a numberplate. I was rather disappointed when I measured them an found that the difference in thickness was 0.005". Chasing accuracy for the fun of it?
JimB
|
Michael Gilligan | 23/09/2019 13:37:27 |
![]() 23121 forum posts 1360 photos | Posted by Jim Butler 1 on 23/09/2019 13:18:07: [ ... ] Chasing accuracy for the fun of it? JimB . ... an admirable pursuit for the true amateur MichaelG. |
Howard Lewis | 23/09/2019 18:45:16 |
7227 forum posts 21 photos | Being realistic, if the part is the base of a clamp for a toolpost clamp, setting with a spirit level, or a digital angle gauge should be OK. Visually, unless it is well out of line, unlikely to cause a problem. Unless you are an absolute perfectionist with time to spare. It won't function any better because it is within a second of a degree!. If it has to interface with some other part so that the angles match then things will be different. Again, as long as the angles complement each other, is the absolute value critical? Howard |
Robin Graham | 06/10/2019 00:15:54 |
1089 forum posts 345 photos | Thanks for your replies, and apologies for my delay in responding - stuff happened. Back in the saddle now. I do take the points about being over-obsessed with accuracy. It doesn't matter too much in this case I agree - I could probably do it by eye - but, as a self-teaching amateur, that's the way that I work. I've read posts from people who have who have had formal engineering training saying that they were required to file down a cube to a thou in size and squareness. Obviously not the most efficient route to the end product but good training. In my own experience, when first I got a lathe I would turn to the limit of what I could measure even when it was unnecessary for the project. That's stood me in good stead in that I can now turn to within a couple of thou confidently and quickly - two thou seems bags of room! It's the same with workholding and the many other things I have to learn. For me it's not all about the destination. In doing something I've not done before I try to get knowledge and skill which will help with something I've not even thought of yet. Lord only knows what the final destination is - for the mo I just like making things from metal! Thanks again for your comments, Robin Edited By Robin Graham on 06/10/2019 00:17:08 |
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