BT48 Rebuild

[dewey_dog]

I started this thread in modifications but other things drew me away from the rebuild of this BT48. I have now completed it, this is where I started. I disassembled the entire machine to start from the ground up.
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27683&stc=1

First was to make the legs rigid and to set up the base plum,level and square. I dropped the cross members down to accommodate linear bearings and a t-slot aluminum table.
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27684&stc=1

[dewey_dog]

Table set up and then off to the weld the base together will continue soon.

http://www.talkshopbot.com/forum/attachment.php?attachmentid=27690&stc=1

http://www.talkshopbot.com/forum/attachment.php?attachmentid=27691&stc=1

[GeneMpls]

[QUOTE=dewey_dog;189208]I started this thread in modifications but other things drew me away from the rebuild of this BT48. I have now completed it, this is where I started. I disassembled the entire machine to start from the ground up.
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27683&stc=1



How did you get that tiny dog to balance on the blue upright is what I would like to know?

[dewey_dog]

I took a lot of training but he has mad balance skills now. I wondered how long it would be till someone noticed that.

[James M]

Oh! I thought you photoshopped the picture! LOL

Congrats on the success of your dog training program!

[dewey_dog]

Actually Otis (the dog) is standing on my bench waiting to get his nails cut when the photo idea came to me.
I digress back to the build, the THK linear bearings for the moving table were difficult at best to properly align and it took a special iron manipulation tool with optional torque enhancer to co-horse the large angle iron within shimming tolerance for the linear bearings.
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27694&stc=1
This level made it much easier to shim the bearings level with precision washers from McMaster Carr. but bolt hole layout must be
precise.
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27695&stc=1l
After the base was welded I painted the base SB Blue again. I then focused re-building the gantry. I then quickly found that the old gantry sides were not going to work because there was not enough clearance. I had two new sides and gussets milled.
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27696&stc=1
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27697&stc=1

[Ajcoholic]

This is very awesome so far.. Are you done and just documenting the build? Or is it as you go in real time??

I love your dog. I miss having one around the shop. My shepherd used to jump up on the work benches too. Usually wanted to lie right where I needed to work too. All 85 pounds of her.

[dewey_dog]

Ajcoholic thanks, this is done and running. Kudos to SB supports Frank and Tom for the help on the power up snafu's.

So after the sides were milled it was time to reassemble the gantry. I was going to use the v-rollers but as I was knee deep already I decided to troll ebay again and found a set of NOS THK SHS 25 bearings for the Y axis. One thing I have learned doing this is read and educate yourself on the working parameters of the linear bearings. SHS can be used in any orientation where SR should be used horizontal etc. and only use new not used ask me why....
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27709&stc=1
The placement of these rails is obviously critical so I set the first using a caliper and the second lower with a scrap piece of aluminum bolted to the bearing trucks so they were equidistant.
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27710&stc=1
The y axis now needs to be addressed as the linear bearings hold the Z car out further so a piece of 1X1.25 stock created the proper offset and the rack was attached with 3M tape like factory.
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27711&stc=1
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27712&stc=1

[dewey_dog]

Next came the Zcar I trolled ebay again and found some bearings that worked. I made a new car from .5" machined plate and the bearing mounts from .75"
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27761&stc=1
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27762&stc=1
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27763&stc=1
Then mount the gantry sides

http://www.talkshopbot.com/forum/attachment.php?attachmentid=27765&stc=1

[dewey_dog]

It was time to mount the gantry.
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27766&stc=1
This went better than I expected and the hoist made it safe and easy.

[dewey_dog]

The machine was now together and I wired it and set the new spindle.
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27775&stc=1http://www.talkshopbot.com/forum/attachment.php?attachmentid=27776&stc=1
http://www.talkshopbot.com/forum/attachment.php?attachmentid=27777&stc=1http://www.talkshopbot.com/forum/attachment.php?attachmentid=27778&stc=1
I am running the machine with a lenovo all in one which is on a swing arm to get it out of the way when not in use. I cut some aluminum engine mounting brackets for a flat bottom drag boat and the machine cut flat and true. Thanks for reading.....DD

[Ajcoholic]

Dang that looks awesome! I thought my modified table was cool... your's is another level up!

I often thought about weighting the bottom of the buddy (I have mine now in permanent position and dont wheel it around) with sand bags, as many with large turning lathes do. You know, close in some of the frame and add 1000 pounds of sand bags to give mass and damp vibrations.

Any thoughts as to whether it would be beneficial or not?

[dewey_dog]

Dang that looks awesome! I thought my modified table was cool... your's is another level up!

I often thought about weighting the bottom of the buddy (I have mine now in permanent position and dont wheel it around) with sand bags, as many with large turning lathes do. You know, close in some of the frame and add 1000 pounds of sand bags to give mass and damp vibrations.

Any thoughts as to whether it would be beneficial or not?

Thanks AJ, I made gusseted L brackets out of 3/8 steel and bolted all 4 legs to the concrete with 5/8" bolts needless to say it doesn't move.