[David589]

I really enjoyed all the photos. I may someday make the plunge and get the BF20 to cnc convert as you have done.

[zamazz]

Get Tapatalk... It's the best $3 I've ever spent on an app. It's actually the only $3 I've ever spent on an app, but it is well worth it. You can always remember the codes for the smilies if your that devoted. It's easier to do than pulling up that menu, especially if you only use a couple of them regularly.

[Mad Welder]

Get Tapatalk... It's the best $3 I've ever spent on an app. It's actually the only $3 I've ever spent on an app, but it is well worth it. You can always remember the codes for the smilies if your that devoted. It's easier to do than pulling up that menu, especially if you only use a couple of them regularly.

hi there zamazz:wave: welcome to my thread...don't think I've come accross a post from you in here yet.....as I blunder my way through all thingys CNC and electronically related....all comments welcome, and thanks for secconding BAMCNC's taptalk suggestion and I suppose guys really the reason I hadn't gone down the taptalk route was I misunderstood the one off purchase fee and thinking that once you signed up you'd get the usual app popup of "you must update your version of taptalk today for the tiny fee of $$" so thanks guys I suppose it really IS a one off signup fee.....

now next thing is to increase the size of my mobile phone screen so I can read the 'dust mite' sized letters...I was thinking maybe a screen size of 4' x 4'..

[Mad Welder]

With my progress of adding a Power Drawbar(PDB) upgrade what I have found so far is that the MT2 taper may not be a really suitable spindle taper to add a PDB to...it seems to me that the taper is simply too long to make it practible I suppose what I mean is with the length of the small angled taper the actual surface area of the tapered collet that is in contact with the angled taper of the spindle is longer than that of and R8 or ISO 30's or similar taper tooling.....what I'm finding is that the MT2 tapered collet just simply gets stuck solid........now so far I haven't added my DIY PDB control motor just yet as I'm machining the mounts that go with it.....so I maybe a liittle to quick off the mark to condemn it before it's built.... but just an observation...I did machine the drawbar end to accept a 17mm wrench..

[diyengineer]

Using Tapatak 2 on my iphone 4S with no issues. As much as im on cnczone, its money well spent.

[Gary588]

Flippin heck I think I should change my user name, didn't login to youtube from my normal routine to get my youtube link in response to BAMCNC's request, but......

[BAMCNC.COM]

Tapatalk fixes any font size issues, no more zooming in.

[ChrisAttebery]

+1

I use Tapatalk on my 4s and my Nexus 7. Both versions work great (when Tapatalk works with the site).

[Mad Welder]

Thanks for the assurances guys

[Mad Welder]

I tried but failed to up load these pics in my previous update post so hopefully this will work


http://i1303.photobucket.com/albums/...psaf812615.png

http://i1303.photobucket.com/albums/...psd253816a.png

http://i1303.photobucket.com/albums/...pse44505f2.png

[SCzEngrgGroup]

With my progress of adding a Power Drawbar(PDB) upgrade what I have found so far is that the MT2 taper may not be a really suitable spindle taper to add a PDB to...

MT will not work well at all - you'll find it takes a LOT of force, or a good shock, to pop the taper free. If you must use MT, just apply the release force directly to the spindle, and you should be able to make it work. Also coat the taper with a very thin film of anti-seize, and clean and re-coat it every few weeks. All the hand-wringing about applying force to the spindle bearings is just that - they are more than capable of handling the load of a PDB release, especially on a smaller machine like a BF20.

Regards,
Ray L.

[waltpermenter]

MT will not work well at all - you'll find it takes a LOT of force, or a good shock, to pop the taper free. If you must use MT, just apply the release force directly to the spindle, and you should be able to make it work. Also coat the taper with a very thin film of anti-seize, and clean and re-coat it every few weeks. All the hand-wringing about applying force to the spindle bearings is just that - they are more than capable of handling the load of a PDB release, especially on a smaller machine like a BF20.



Regards,
Ray L.

hand-wringing? who are you putting down with that statement? read tormachs white paper on the subject did you? NO strain on the bearings is still more advantageous no matter how you look at it.

[ihavenofish]

With my progress of adding a Power Drawbar(PDB) upgrade what I have found so far is that the MT2 taper may not be a really suitable spindle taper to add a PDB to...it seems to me that the taper is simply too long to make it practible I suppose what I mean is with the length of the small angled taper the actual surface area of the tapered collet that is in contact with the angled taper of the spindle is longer than that of and R8 or ISO 30's or similar taper tooling.....what I'm finding is that the MT2 tapered collet just simply gets stuck solid........now so far I haven't added my DIY PDB control motor just yet as I'm machining the mounts that go with it.....so I maybe a liittle to quick off the mark to condemn it before it's built.... but just an observation...I did machine the drawbar end to accept a 17mm wrench..

mt2 is self holding. once tight, you can remove the drawbar entirely. it will stick to the point of needing a 5lb sledge to remove. even if you just barely tighten it, the forces from milling and drilling will push it in. generally not suited to ATC.

[Mad Welder]

MT will not work well at all - you'll find it takes a LOT of force, or a good shock, to pop the taper free. If you must use MT, just apply the release force directly to the spindle, and you should be able to make it work. Also coat the taper with a very thin film of anti-seize, and clean and re-coat it every few weeks.........

Regards,
Ray L.

I had already replied to your post yesterday but I guess it's floating around in the either abyss. ..so here's it again

Never thought of the anti-seize...nice one..........and I kinda figured that the MT2 wasn't really suitable but either way I'm learning a lot as I go on

[Mad Welder]

mt2 is self holding. once tight, you can remove the drawbar entirely. it will stick to the point of needing a 5lb sledge to remove. even if you just barely tighten it, the forces from milling and drilling will push it in. generally not suited to ATC.

And also my reply to you yesterday is floating around the either abyss too

So here goes again. .....Thanks for that and I came across that on Wikipedia when I Googled 7/24 taper too.....typing this from my phone so I don't have the link but it's interesting reading there for anyone else reading this post and is looking for info on all available spindle and tool holder tapers....

[Mad Welder]

It's not the best video and I should have cut the last minute of it. .....I didn't realise that the phone was still recording

anyway the video is cutting the mounting plate/bracket for the planetary gear box I'm going to try out. ....not sure if anyone has attempted like me to use the planetary gear box of a hand drill.....I have a 17:1 ratio and I'm going to use a 960ozin stepper nema34 frame. .and as the gearbox has its own alloy frame I have made a plate in two halves and these plates will secure the planetary gear box to the stepper motor (pretty good as it has turned out thankfully)

http://m.youtube.com/watch?v=H-lGVLtHV88&feature=plcp

[Mad Welder]

[SCzEngrgGroup]

The stepper motor and planetary gearbox should work fine - I've built several PDBs this way. The drill/driver gearbox will be very inefficient, and noisy. Be sure you support the output shaft well, so the load on the gearbox is purely torsional - no bending - or you'll wear out the gears, or break them, quickly. Also, use a smaller stepper motor - with that one, you'll have FAR more torque than you can use, and if something goes wrong, it'll break your drawbar, strip the tool holder, or wedge the collet into the spindle so tight you'll have one helluva time getting it out. A motor with half that torque would still be more than adequate. Use current limiting on the stepper driver to limit tightening torque to less than the loosening torque, or you won't be able to reliably release the tool. Even worst case with TTS, 30 ft-lbs on the drawbar is mero then enough.

Regards,
Ray L.

[Mad Welder]

Yeah I knew you'd gone the planetary route as it was you had suggested to me a good few months ago when I started a thread asking for info regarding the use of electronic linear actuators. .....I was curious though if anyone had used the gearbox from a hand drill?......however thanks again Ray as the linear force causing unwanted damage to the small gearing hadn't occured to me and I guess this was the answer I was looking for as whether the little gear box would be suitable for my use....








When I use additional force (like my vice) I can close the two brackets completely.....I guess when I measured the alloy casing I never allowed for fitting so tis like a bearing fit now as I must press fit the bracket to the casing and I'll either drill and tap or drill and fit spring roller pins to keep it secured..

[SCzEngrgGroup]

As I said, the gearbox should work fine, if you mind its limitations. Those drill/driver gearboxes have been used successfully in all kinds of machines, and they're very common in robotic applications, due to their low cost. Don't know where you got yours, but are you aware you can buy them brand-new as replacement parts from the drill/driver manufacturers?

Regards,
Ray L.