JasonB | 16/02/2019 07:29:34 |
![]() 25215 forum posts 3105 photos 1 articles | Possibly something in the last photo but not good practice to move the item around when taking the readings, should be laid across the table and then the table wound across. For best results swap slip end to end and take measurements again to eliminate taper in slip. Also best to get rid of the spring adjuster on the DTI stand Edited By JasonB on 16/02/2019 07:31:05 |
JasonB | 16/02/2019 07:46:50 |
![]() 25215 forum posts 3105 photos 1 articles | I'm not sure of how these measurements are being taken. You said you wound the table front to back and got 0.008" difference. yet looking at the two photos taken from the end of the table the dti has been moved or swung. This one is taken from the right of the machine as you can see the handwheel bottom left But this one has been taken from the left hand end as you can see the bellows and DRO wires So either it has been swung and that is a tram measurement or the photos are posed and don't show slope on the table.
Edited By JasonB on 16/02/2019 07:47:37 |
Ron Laden | 16/02/2019 07:52:19 |
![]() 2320 forum posts 452 photos | Posted by JasonB on 16/02/2019 07:29:34:
Also best to get rid of the spring adjuster on the DTI stand Edited By JasonB on 16/02/2019 07:31:05 Jason, I always use my DTI with the spring adjuster fitted, can they throw up errors..? Ron |
JasonB | 16/02/2019 08:04:27 |
![]() 25215 forum posts 3105 photos 1 articles | Yes |
Nicholas Farr | 16/02/2019 08:41:34 |
![]() 3988 forum posts 1799 photos | Posted by Ron Laden on 16/02/2019 07:52:19:
Posted by JasonB on 16/02/2019 07:29:34:
Also best to get rid of the spring adjuster on the DTI stand Edited By JasonB on 16/02/2019 07:31:05 Jason, I always use my DTI with the spring adjuster fitted, can they throw up errors..? Ron Hi, I agree with Jason that these spring adjusters will throw up errors and they a not always consistent errors and especially when chasing the accuracy the OP is after. Your DTI needs to be as ridged as possible. Regards Nick. |
JasonB | 16/02/2019 08:57:18 |
![]() 25215 forum posts 3105 photos 1 articles | Just for completeness this is what I would have expected to see via way of setup when "turning the handwheel" which will give an indication of how true the top of the table is to the dovetails. You seem to have shown photos of teh spindle being rotated as per my earlier video. |
FMES | 16/02/2019 08:59:18 |
608 forum posts 2 photos | Posted by JasonB on 16/02/2019 07:00:54:
Posted by FMES on 15/02/2019 21:53:59:
Robert, if you are holding that DTI in a chuck and not a collet that is probably where a lot of your error lies.
As the dti is not being revolved it makes no difference how it is held or on what part of the machine it is fixed to. Your first photo shows the DTI on something laid across the table but the last seems to show it directly on the table but there is 0.008" difference between first and last reading. Jason, the background looks like its changing in eack of the photos so it is being rotated, Robert confirms he's using an er32 collet - in an R8 holder?? Why not an R8 collet? going from R8 to ER32 may well have introduced errors if not spotlessly clean. In any case, it would be far better to allow the Warco staff to come and have a look at it and advise accordingly rather than play message ping pong trying to diagnose a problem from afar.
Regards |
JasonB | 16/02/2019 09:03:32 |
![]() 25215 forum posts 3105 photos 1 articles | FMES I have also posted above that the photos seem to show the dti being rotated which was not what was said hence my comments. Until it can be confirmed what test was actually done and how then we can't help much as one result is fixable and the other not. I would also say if tramming the table as the photos seem to show then don't have the vice sat on one side of the table as can be seen as it WILL affect results. |
Former Member | 16/02/2019 09:46:32 |
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Former Member | 16/02/2019 09:49:41 |
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Robert Askew | 16/02/2019 10:10:58 |
32 forum posts 2 photos | Well I will know for sure this afternoon the maintenance guys from where I work are coming this afternoon with all there test equipment to tell me how far it’s out and before I get comments on how good they are we work for a well known helicopter manufacturer |
Nicholas Farr | 16/02/2019 10:15:35 |
![]() 3988 forum posts 1799 photos | Posted by Robert Askew 1 on 15/02/2019 16:35:35:
.008” over full with of table 8.5 “ Hi, am I missing something here. Your DTI is reading a tad over .08mm, which in my book is around .003" Regards Nick. |
Former Member | 16/02/2019 10:16:02 |
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Former Member | 16/02/2019 10:16:59 |
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Chris Trice | 16/02/2019 10:17:51 |
![]() 1376 forum posts 10 photos | One could simply machine a block of something and then check for consistency of thickness as at least an indicator of what is going on. A sheet of paper under the block will help stop marking the surface if it needs to go back. My first test would be clamp a piece of aluminium L section along the y axis, skim the upright edge and then measure it. Edited By Chris Trice on 16/02/2019 10:21:19 |
SillyOldDuffer | 16/02/2019 10:18:08 |
10668 forum posts 2415 photos | Hi Bob, I hope you don't think the posts questioning your measurements are unhelpful. Rather they are trying to confirm whether you have a genuine problem or not. No advantage to you rejecting an acceptable machine due to a misunderstanding - though it sorts out in the end, the bother and hassle of making a return is considerable! Background to the questions is a forum history of chaps buying new Chinese for the first time and starting by taking dodgy measurements to prove to themselves the machine is OK. The problem is that taking accurate measurements demands a level of understanding, skill, and technique that not everyone has. It's not easy and beginners often get it wrong. Actually, experts get it wrong too, it's just that they are alert to the possibility and don't automatically trust anything! Sometimes these chaps are right, sometimes they're just torturing themselves. One hint that mistooks may have been made is posts saying something like "x Axis spot on front to back y axis.008 out". Suspicions of beginnerism arise because units aren't specified, nor the distance over which the slope was measured. Also, there's no information in your posts about the method used to take the measurement, plus a sense of a man in hurry! From my armchair, it suggests - probably wrongly - that your measurement technique might be the problem. I suggested earlier that you test the machine by cutting metal and looking at the results. The advantage is cutting shows what the machine is actually capable of rather than inferring what it might be. Also this type of simple test is less error prone. Of course, if the machine produces poor results, then you measure the machine to identify the cause. None of this questioning means we think you are wrong, only that it saves you a lot of bother by confirming you're right. It's entirely possible that your machine is faulty or out of adjustment. On first installation, adjustment errors do happen as a result of transport, lifting into place, operator error, or a problem with the stand. These can be fettled. But although Chinese machines seem to have improved over the years they aren't assembled or inspected to high standards making it possible yours is a wrong-un. The best resolution is that an ordinary non-intrusive adjustment fixes the problem. Second best is Warco replace a faulty machine with one that's within spec. Third best is you get your money back and start again. If your measurement is correct, then the tilt is about 7x what it should be - not good. Dave |
Bob n About | 16/02/2019 11:31:24 |
60 forum posts 1 photos | My setup for tramming the mill and setting the table or accessories bolted too it. I'm not going to fret over the vice being present or some bits of tooling on the table, the power feed is hanging off the left hand side !!! My front to back readings, note the indicator is at the same angle and lever adjusted to reduce cosine error. For tramming the head I move the vee blocks around the table to get best readings. 300mm in X, and about 200mm in Y The machine here is used for work, so I am not going to spend hours chasing precision an order of magnitude greater than required. This really is good enough and no doubt that will shock the purists, but hey. And finally. Those eagle eye'd will notice my mag mount hanging off the drill chuck. If your spindle is that bendy, machining metal ain't for you my friend. I can set this up get the mill as true as I need it in the space of a few minutes. |
Neil Wyatt | 16/02/2019 15:48:47 |
![]() 19226 forum posts 749 photos 86 articles | Posted by Ron Laden on 16/02/2019 07:52:19:
Jason, I always use my DTI with the spring adjuster fitted, can they throw up errors..? Ron I recall JS telling me the best improvement to any of those stands is to replace the sprung bar with a solid rod. N. |
FMES | 19/02/2019 06:13:47 |
608 forum posts 2 photos | Posted by Robert Askew 1 on 16/02/2019 10:10:58:
Well I will know for sure this afternoon the maintenance guys from where I work are coming this afternoon with all there test equipment to tell me how far it’s out and before I get comments on how good they are we work for a well known helicopter manufacturer Come on Robert, don't keep us in suspense, what was the outcome? Regards
|
Adrian 2 | 20/02/2019 12:52:26 |
104 forum posts 19 photos | I have been considering one of these machines for a while now, and followed Robert Askew's posts with interest regarding the problems he is experiencing with his new machine. His post generated a lot of discussion and opinion. I am sure like me, other members would be interested to know the latest developments. Over to you please Robert. Regards Adrian. Edited By JasonB on 20/02/2019 14:35:35 |
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