BF30 CNC #9 - Homing Electronics

[@JoelArseneaultYouTube]

Interesting, I didn't pick up on it earlier, but now that you mention the MT3, I do recall seeing it in a few earlier videos. The PM30 uses an R8. Collets are designed to get "stuck" in the spindle. This is the whole reason for the taper. If it doesn't get tight, the taper isn't fitting properly and won't be accurate / repeatable and will also likely slip causing damage to your spindle and tooling. My old R8 machine requires a light hammer tap to get the collet free. Some older machines came with a brass hammer and place to store the hammer on the head of the mill. You can do two things to remedy this. 1. Make your drawbar so that it is retained. You would likely have to remake the drawbar with a durable flange on it. Then attach a cap to the top of the spindle. When you tifhten the drawbar, it pressure is on the top of the spindle. When you loosen the drawbar, after one or two turns the top part of the flange pushes on the cap and pushes the MT3 out. The down side of this is that you will almost certainly loose the use of your Z quill feed, as the cap will not have clearance to go inside the spindle. 2. There are many ways to make a power drawbar. This always consists of the drawbar tightening against a stack of special bevelled washers. Basically. this needs to be calibrated so that you can torque your drawbar to the required setting, yet not completely compress the stack of washers. Once you have a spring holding tension on your drawbar, you now can choose some method of pushing down on the top of the drawbar and overcoming the spring, and locked taper. This takes over 1000 lbs of force on an R8. I have seen this done with a mechanical handle that had two levers to step the force way up, but more commonly people use pneumatic cylinders. You can buy a kit from priest tools but it is over $1000 US so many people make them. I'm not sure that this will work oris a good idea on a MT3 so you should do your own research about it... I'm at the disadvantage of commenting on a video that is two years old.... so forgive me if this information is too late, and / or useless.

[@DarkArtGuitars]

Thank you for all your comments, I'll take the liberty to just respond here. R8 is definitely the better choice as it has a steeper taper angle, making it easier to release. Depending on the exact tool and how long ago I put some oil on the taper it sometimes takes quite a bit more than a few "taps", but it works. I haven't really done much with this machine in the last two years as I got busy with other projects and there is still a daunting amount of little things to fix until it works as I would like. I wish you the best of luck with your conversions and hope you get well soon!

[@JoelArseneaultYouTube]

​@@DarkArtGuitars It is obvious from your channel content that you are a very busy person and have a lot of projects on the go. I learned a lot from watching your series. Yes, the R8 is a better spindle for a lathe application. The MT is designed to lock in with very little pressure into things like lathe tailstocks where you don't use a draw bar. Seating it with a drawbar, and then seating it further by using it with tension on it, really locks them in place. My lathe has MT3 tailstock and MT4 in the spindle. I often find myself in the situation where I'm challenged with a daunting amount of work with one or more project. Sometimes I take a look back at my videos from two years ago to give myself some perspective on what I'm capable of, given some time. It looks like you enjoy your projects, so keep doing what you enjoy.

[@mwmxcnc]

Do you mind sharing your acceleration and velocity settings for your motors? I’m struggling a little with a good base setting. And did you connect your alarm signal from your drivers to Mach? I’d like to do that so if a driver alarms, the program stops. But I haven’t figured out how to do that. I have the same steppers/drivers as you. And the ESS but I used a c11g bob. Thanks for the videos, they’re very well done.

[@DarkArtGuitars]

I talked a bit about the velocity in the last video, as for the drivers, they are not giving any feedback to Mach4. I haven't really looked into that, I know they have some sort of proprietary interface for some stuff, but I'm not sure if they also have more simple alarm pins. I'll probably look into that when I rework the electronics cabinet in a little while.

[@mwmxcnc]

I’d recommend looking into the alarms, I think I need a second or bigger bob to hook them up, but it’s a bad day when an axis alarms, but the program keeps running. It’s happens 3 times to me in about a week.

[@makosharkcnc7730]

i'm going to work on my homing switches soon too

[@hippie-io7225]

Love your videos! You have made tons of progress relative to when you first started. Good on 'ya! Have you considered leaving out background music? It reduces the clarity of your dialogue.

[@mrechbreger]

Hast Du mit der Maschine überhaupt schon mal was gefräst? Dachte nicht dass ich mit meiner Maschine schneller fertig werde als Du mit Deiner. Die Endstops/Limits finde ich nicht besonders gut angebracht, ich hab meine direkt unterhalb der Maschine. Ich hab aber auch ne deutlich kleinere vergleichbar mit der BF18 denke ich (musste daher auch deutlich mehr nacharbeiten um die Kugelumlaufspindeln reinzubekommen)

[@ifeelcnc4891]

Hi, you shud put hammer drill on milling machine insted of impact driver then you dont nead to hammer it by hand. keep up good work!

[@DarkArtGuitars]

I'm not sure if it would have enough torque, as it isn't really designed to tighten bolts. Also I would have to find one that has a clutch, to not kill the motor when the tool is clamped. But let me know if you have any experience with using a hammer drill for this application, or know of anyone who does.