Member postings for JasonB

Spray "high build filler/primer" will do a lot of small surface inperfections. Put that on and it will show up larger problems which can be knifed and then rub it right down before using grey/red primer. Something like U-Pol's "High-5" is what I use.

More detail of how I prep and paint castings in this thread

Sounds like a threaded version of a clevis pin like this one with an end that pivots to lock in place.

Thanks again Barrie, I do seem to remember from the videos that you can pick certain areas of the contour and specify different speeds, cutting directions etc which is something I will have to study more. I also need to find where to change stepdown to step over. Will also look to reduce the roughing steps.

I just changed the tool to a 6.0mm dia 1.0mm corner radius one and ran the simulation. At my max speed of 5000rpm it gives a surface speed of 95m/min which is the full 6mm dia so allowing for the 1mm radius the cutting speed when the very bottom of the tool is being used at the top of the dome would be around 63m/min at 4mm diameter which is quite an improvement on the near zero speed of the 3mm round nose tool. I also has the bonus of being able to finish the flat areas in the corners and would not be too bad to do the initial roughing as well so no need to change tooling.

Blue line shows path of ctr of the tool which is now further from the finished surface so actual cutting speed is up.

Thank's Andrew, you assumed correctly that the contour was a series of circular cuts and as you say the middle of the cutter will not be doing much at the top pf the dime. I remember Murray's post about tilting the work which worked well, not having even 4th let alone 5th axis the other option that may be more affordable would be to invest in a radius corner cutter or "Bull Nose" as the Americans call them which would get the speed at the cutting edge up. I may simulate that as F360 has those cutters already in the tool library. Only downside I can see in using them is you can't get into tight internal corners in the X-Y plane.

Barry, there are several options that I still need to get my head around depending on the orientation of the curves on the part where the path can be set to give a more suitable step over. I need to watch the video again and do a few more trials to see what works best.

For the clearing I used 0.5mm cuts and 1mm vertical steps, the final contour to the dome was done with 0.1mm steps. Purple is waste still to come off, set to leave 0.5mm which I assume its at teh thinnest points and that would be about 1.3 at its thickest.

Had a go a 3D machining this evening, just a simple dome but quite pleased with it for a first attempt. Did adaptive clearing to get rid of most of the waste, then finish machined the 4 flat areas at the top of the square with a 6mm 3-flute cutter before changing to a 1/8" HSS ball nose to refine the dome.

Ball nose was a bit past its best so possibly explains the poor cuts towards the top and I did not spend long enough setting tool heights right so a bit overcut where the dome fillets out to the flat.

I too use the ones from Polly though mostly I buy direct from their supplier GHW in Germany. They are all machines and not stamped out though I think M4 is the largest they do having a 5.5mm hex. I do find the M4 a little bit tall so tend to skim 0.5mm off the bottom, the smaller sizes are OK.

Looks good Ron, hope the traction engine will run as well.

As the carrage sits on the front vee and the rear flat the cutting loads are not going to be over a pair of either. I think you will find the spindle is centered over the whole be give or take a few mm.

Regarding the other questing I'd be looking into why your discs wear so fast unless you are doing many miles or the car is sitting with them rusting away.

You will also find that the two legs of the carrage stop you getting near the disc so tool overhang will be a lot, I have found this when turning 10" flywheels which will hit the yellow bits.

Edited By JasonB on 24/04/2019 13:40:19

This is why in this thread and the one linked to by Neil requests about your system, etc have been asked for, yet are not forth coming. It saves people wasting time guessing what you have.

From Neil's lack of posts over the last couple of days I assume he is not wearing his MTM gnomes hat at the moment but I'll ask him to look at this thread again when he is back in the grotto.

regarding size of old back issues, once you click on a page it will become larger and then a roll of the mouse wheel will allow the size to be altered, just did it to confirm on the oldest mag in the archive.

I would be interested to know how you are printing from the most recent mags as anything published this year can't easily be printed apart from snipping which reduces resolution and is a long winded way to do things. These use an HTML5 viewer not a Flash based one.

Did you get your touch screen up and running Steve?

I did use Cut2D for the first few test items but have not used it for any actual parts. agree it is quite easy to get the hang of but I have not found F360 CAM any harder to pick up and that is what I'm using now. As it imports a STEP file you get heights which you don't when using a DXF in Cut2D and no need to join all those vectors together.

Nick as has been suggested by me, Neil and in the linked to thread you could try another Browser, I managed to print OK using Chrome. Neil generally uses Firefox and he says he was able to print OK so may not be a Firefox issue.

Have you tried another device as I suggested earlier?

Yes I'm just a volunteer and this is about as far as I can help. Do have a read through the thread that Neil linked to yesterday as that has some suggestions such as trying a different browser etc. If that does not work give more details of your system as was requested from the user in the linked thread and hopefully Neil or Kate may be able to help further(they both get paid to do that)

Also look at your inbox -top of page.

J

Edited By JasonB on 23/04/2019 16:32:58

I've used Vee blocks and ER Collet blocks in the past. if the block is placed in th emiddle you can locate off the same side of the block which will pick up the length and having a flat surface you can register that to the table so there is no risk of round parts twisting out of position when moved about.

I have just printed off a page without a problem this time using the icon at the side of the page this time.

Have you tried printing to PDF rather than a paper copy I have also done that OK, you should then be able to view the pdf or print from that.

As someone who makes bespoke kitchens and other cabinets the standard size is 5mm, dowel drills are 5mm and all studs and other cabinet fittings are made to suite 5mm nominal holes.

Assuming it the ones that start in 4189 then you should be able to print. If not what issues are you trying to print from?

When you get to the page you want click it which will zoom in and at the top you should see a tab "print this page" click on that and it can be printed to paper or PDF.

I don't think it will make a lot of difference, not sure what size your gear is but if say 2" dia then it is only a thou off the tooth at its outer edge. If you recalculate the offset to this new angle then that should be reduced.

I suppose you could work out the roll for the other gear and go the opposite way so you either have big gaps with big meshing teeth or small gaps in this wheel with larger teeth on the pinion.

Edited By JasonB on 23/04/2019 08:40:31

Page 110 shows which way to move but basically you want the middle of the cutter to still line up with the ctr of the cut at its inner end so if your roll rotation makes the groove lower then lower the tool, if when you roll the gear the groove is above ctr then raise the tool.

Edited By JasonB on 23/04/2019 07:07:28

10.5" dia and very heavy due to the thick section rim.