Hello,
Couple of days ago I bought an ZX7045B1. Compared to the rest of the machines I saw on this forum it has an automatic quill downfeed with tapping function and a base casting a bit wider with a small internal coolant tank with pump.
I bought it second hand for 10000kn (1450$ US dollar equivalent) with a stand, coolant pump, 80mm indexable face mill, jacobs chuck, ER collet chuck, large machinist vice and a couple of endmills of different size. New machine costs 18125kn (2665$ US dollar equivalent) and I didn’t want to buy a new machine just to take it apart and make all the modifications that I want to do.
The milling machine wasn’t maintained properly but it wasn’t abused either. Previous owner used it as a drill press. The mill isn’t a horror story as some mills seen on this forum but it’s not best. Typical casting sand leftovers, 2-3 mm bondo on the strategic places on the main column and base.
This forum was helpful with lots of tips on how to disassemble the mill and transport it. Stacking wooden blocks below the head, unscrewing it and moving it away from the column with Y axis. Using an engine hoist to remove it from the stand, taking apart the column from the base are all the tips that I saw on this forum and I’m grateful to the people posting that because it took us only 2 hours to take apart the mill , package everything on a trailer and haul it away.
Why an 7045??
I’m a mechanical engineer, and I like to design stuff. I have a thick background in motorsport coming from Formula Student (FSAE) competitions, local hillclimb/ track day racing , to currently working in automotive industry. I was always interested in machining and 7045 is the biggest machine I can take apart and carry it into my basement where I have space to place the machine.
My plans for the machine:
1. Take it apart -done
2. Clean and inspect it- in progress
3. Make a detailed CAD model
4. Assemble it back and use it as a manual mill
5. Design a CNC retrofit
6. Produce the parts for the retrofit with the mill
7. Take it apart again and do the necessary modifications for the CNC mill.
8. Make parts
When we unloaded the machine, the head was in a large plastic container (TIP* easier for 2 people to carry it since the awkward shape of the head doesn't allow for secure grip on it).
Column was separated from the base (will require tramming on assembly ).
Table (X axis), Y axis and the base was transported in one piece with the engine hoist.
Today I took apart the X and Y axis.
The parts where still covered in cosmoline after 7-8 years of use by the previous owner. Cleaned all the dirt and metal shaving’s with an industrial grade detergent that I usually use to degrease the engine and gearbox blocks. After washing all parts where covered with WD40.
There was some paint in the gibs which I scraped away with a blade and some scotch brite.
All bolts where cleaned in a solution of the same industrial detergent in a ultrasonic cleaner. It’s easier to load everything into it and work on cleaning other parts while the ultrasonic cleaner buzzes away. Only fault with the mill I found is one cracked leadscrew nut. I can TIG weld it to use it as it is. It’s going to be replaced with a ballscrew anyway . Cleaning the leftover casting sand from the bottom of the table went easy with a carpenter’s chisel, I’ll try with a angle grinder and a steel brush tomorrow to get all the little pieces. Castings look really accurate below all that sand. Cleaning the inside of the column will be a bit more difficult because of space constraint.
CNC plans are:
1. Ballscrews 2505 (stock leadscrews are 24mm I’ll have to do some calculations to see if I can gain some more travel and what will fit into the machine ), I have to check the ball size and the possibility to use oversized balls
2. 750W Brushless servo motors with 220V drivers, I found a cool firm in Europe that sells cheap 3 axis kits.
3. HIWIN linear guides as an option to increase travel and reduce the driving losses of the axis.
4. ISO 30 taper spindle, there are couple of firms here in Europe that sell the ISO 30 spindles for these machines or I’ll get one made. Machine currently has MT4. Cheaper alternative is to get a 20mm collet for the MT4 and use 20mm straight shank ER tool holders.
5. For software I have to do some testing between mach3 and linuxcnc, I’ve used mach3 , it works, but I didn’t use it enough to be able to judge.
6. Removing the gears and retrofitting the head with a VFD controlled main spindle motor/ belt drive, to reduce the noise/increase rpm/have PC controlled spindle.
7. Fill all the voids in the main stationary castings with polymer concrete.(requires cleaning the castings of all sand and debris)
8. Bolt the milling machine to a heavy stand filled with sand or polymer concrete.
I didn’t have my hands free and clean today to take some pictures I’ll do my best to upload some pictures in the following days.