POTD- PROJECT OF THE DAY: What Did You Make In Your Shop Today?

I was referring to the lead screw in the linear actuator not on the Z axis to raise and lower the mill. Here is a diagram of a similar actuator to the one i used:

1720449113928.jpeg

When the motor is turned in one direction the lead screw turns (E) and the nut is fixed (G) so it moves away from the motor and pushes the cylinder rod (C) out. When the motor is turned in the opposite direction everything works in reverse with gravity pulling on the rod end (A) to retract the actuator.

On the one i repurposed the lead screw shaft had nice bearings on both sides of the gear (I) and runs very smooth. I found that the max load on the actuator i used was 6000N which is ~1300 LBS so i figured it would be heavy duty enough. I cut item E about 1" longer than the plastic clam shell case and turned it down to accept the pulley. Surprisingly it cut pretty easily so i'm guessing it wasn't hardened which makes sense as it had a nylon gear (G) riding on it.
 
@ivel03 - I'm glad you posted that because I was still misunderstanding. You and I are using the terms in the same manner. I now understand what you did. I can see the orientation of the motor housing in your previous pic. Did you put a bearing where the lead screw exits the housing?
 
rwm said:
@ivel03 - I'm glad you posted that because I was still misunderstanding. You and I are using the terms in the same manner. I now understand what you did. I can see the orientation of the motor housing in your previous pic. Did you put a bearing where the lead screw exits the housing?
Click to expand...

No, there is a bearing about where the nut (G) is on the one i used. The shaft seemed to be well enough supported to not need an additional bearing at the end of the housing although i'm sure it wouldn't hurt. I made the shaft as short i as i could to minimize leverage and also to make the some what bulky motor package as small as possible.

Here's a pic of actuator i used:

1720451278890.png

As you can see the bearing at the very left and there's another one to the left side of the lead screw nut. The bearings are spaced about as far as you can get apart and still fit in the case which also helps keep the shaft stable. I mounted the motor upside down on the mill. I drilled 3 holes in the top cover and bolted a 1/8" strip of aluminum to it. The plastic is nice sturdy PA6 glass fiber reinforced so i have no worries about the attachment. On the very far left side is the motor yoke - i haven't yet but will likely trim that off as it sticks out and serves no purpose.

I lucked out on being able to use this motor as it is nice and heavy duty and didn't require too much to make it work.
 
Gaffer, if you have a small slow leak, you might look into a leak sealant. I had a very small leak in on of my 5T AC units, spent $$ having AC experts come out, check for leaks, purge and replace the Freon only to have it leak out by the next year. I subsequently used one tube of the Leaksaver with UV dye and charged the system, never was able to find the leak but the leak was for the most part stopped. If all else fails, may be worth evaluating, in my case it was a lot cheaper than a replacement AC system. As other mentioned the valves can leak and should be replaced. I invested in a Testo manifold gauge set and do my own AC charging after getting scalped by the local AC experts that needed to call into their boss to tell them what to do.
www.leaksavers.com

Automotive

Our Direct Inject refrigerant leak sealants are perfect for automotive and car refrigerant leaks. Other stop leaks simply recondition the o-rings. The Leak Saver is a true refrigerant leak sealant that create a permanent seal. Please note that the Leak Saver has standard 1/4" connections and you...
www.leaksavers.com www.leaksavers.com
 
mksj said:
Gaffer, if you have a small slow leak, you might look into a leak sealant. I had a very small leak in on of my 5T AC units, spent $$ having AC experts come out, check for leaks, purge and replace the Freon only to have it leak out by the next year. I subsequently used one tube of the Leaksaver with UV dye and charged the system, never was able to find the leak but the leak was for the most part stopped. If all else fails, may be worth evaluating, in my case it was a lot cheaper than a replacement AC system. As other mentioned the valves can leak and should be replaced. I invested in a Testo manifold gauge set and do my own AC charging after getting scalped by the local AC experts that needed to call into their boss to tell them what to do.
www.leaksavers.com

Automotive

Our Direct Inject refrigerant leak sealants are perfect for automotive and car refrigerant leaks. Other stop leaks simply recondition the o-rings. The Leak Saver is a true refrigerant leak sealant that create a permanent seal. Please note that the Leak Saver has standard 1/4" connections and you...
www.leaksavers.com www.leaksavers.com
Click to expand...
Thank you. I didn't think about leak sealant, but I'm all in now. I decided to tackle it because the shop rate was too much. I'll report back when I get it reassembled.
 
I'm sure you're all sick of my project by now but i typically don't finish things - i just get them good enough to use and move onto the next thing which means that clamp would forever be there!

PXL_20240709_012704401.jpg


While it is 100% functional it's not 100% done - the variable speed + fwd/rev control box is sitting on top of the mill control box still. Need to mount the control box and put a couple of wire clamps on it. Darn it, i was so close.... :rolleyes:
 
ivel03 said:
Well i wouldn't say that the power feed was a total failure but it didn't work well enough to my liking. There were two issues - first the motor spun fast so it had a very nice travel speed up and down however it didn't have enough power at the very top of the travel and didn't lift the head very well. The second issue is that i used a "lovejoy" like flex coupler and threaded the mill side so that it could jam against the other jam nut on the lead screw. Even after using loctite i had issues with the lovejoy unthreading - and it was pulling threads and stripping out so long term it would not hold up.

Neighbor had some linear actuators from a power adjustable bed like these here. I was able to take the lead screw and shorten it, then turn it down to the proper diameter to put a pulley on it. I am driving the hand crank shaft instead of the top nut to eliminate the issue i had with the flex coupler.

Here's a short video:

https://imgur.com/a/VhvSikn

It moves a bit slower than i really wanted but it works really well with plenty of torque so i'll call it a win. If you look closely you can see a C clamp in the video. I attached a bracket to the plastic gear motor housing and attached a block to the mill. I need to drill and slot the bracket so that i can attach the bracket to the mounting block and eliminate the C clamp.
Click to expand...
Moves about as fast as my factory PM940 setup, looks good.
 
Gaffer said:
Thank you. I didn't think about leak sealant, but I'm all in now. I decided to tackle it because the shop rate was too much. I'll report back when I get it reassembled.
Click to expand...
Be careful with ac leak sealant, it can clog up the expansion valve. I tried some on a car many moons ago with no success (evaporator was corroded and leaking), but when I replaced most of the parts I found that the expansion valve was almost completely clogged up with sealant.
 
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