[hive8]

I bought those two bearings for the head when I ordered the rest of my bearings. Figured they were cheap and of known quality. The screw keys into the R8 collet.

Can you direct me what you ordered and where from? I think i just update it too since i have the whole thing apart...

I found the bearing info for the spindle per Hoss's link on his g0704.com site but no info on these 2...

[rob_b]

from my spreadsheet...

VBX.com
Part #.......Size..................QTY...EA............ .RPM.........Use
8891.........35X62X14 AC....1.......$12.95......9,500.......Spindle
8889.........25X47X12 AC....1.......$9.95........13,000.....Spindle
9569.........45x85x19 BB.....1.......$18.88......7,800.......Drive
9537.........35x62x14 BB.....1.......$11.80......12,000.....Drive

As you can see the 45x85 limits the spindle speeds to 7,800rpm. Using the stock motor I sized my pulleys to top out at 7,000rpm.

[photomankc]

I don't know about the G0704 but those upper radial bearings on mine were actually decent bearings as they were and most stuff that was affordable was not really much of a step up in any meaningful way. I was not happy at all when I buggered them up getting them out for something I was doing. Personally I would leave them be.

[hive8]

Thank you for that, i think i will go with a higher on on these 2 somewhere in the 12k range with grease...

9569 45x85x19 BB 1 $18.88 7,800 Drive
8891 35X62X14 AC 1 $12.95 9,500 Spindle

Thank you for the information

Now other question is how do i get them out, kkk... I got the H/L Gear spindle and gears out no problem.

Main Spindle bearings like in the post above giving me a little problem, which on to start from the head side top or bottom, please someone who did it advise.

[rob_b]

I was not happy at all when I buggered them up getting them out

That is another reason I replaced them, during dis-assembly I put a punch through one of the seals. I have also read that a rubber sealed bearing has a slight increase of friction/heat compared to a metal shielded one.

[hive8]

That is another reason I replaced them, during dis-assembly I put a punch through one of the seals. I have also read that a rubber sealed bearing has a slight increase of friction/heat compared to a metal shielded one.

I will take them out since i want to replace them anyways... Question is how to get them out see post before...

[rob_b]

edit: you got it out...

[hive8]

Yeah i got it out... They stuck in there pretty good...

Now one thing, since all the gears are out, there is a lot of room in the head now .

Maybe I make a new design for a belt drive, if there is a good motor, something where i don't need to change the belt from high to low or the other way around. thinking, thinking...

[691175002]

An electric motor will always have (relatively) constant torque, its just the way they work.

If you do not want to switch belts, your motor has to be enormous since it must provide the required torque at a disadvantageous reduction ratio.

You see it in commercial machines all the time, take this hass office lathe as an example:
Haas OL-1 | Haas Automation, Inc. | CNC Machine Tools

There is no way in hell you need 7.5 HP on that machine, but you need a motor that large to "do everything" with a single belt.


You can't really stick a 5HP+ motor on your g0704 so you pretty much need at least two speeds for an effective machine. You can always try to automate the speed change mechanism, but that seems excessive and if it is unreliable could cause some major problems.

[hive8]

So i started today with the scraping, this really goes into your hands, kkk had to do an hour then take a swim in the pool, then an other hour...
I am all hand scrapping, anyone has a idea on how to make a scraping machine, i go any buy on of these vibration cutter, maybe i can mod one, anyone has a other idea?

but you can see a difference...

Before:


After:

[hive8]

So i tested a little more to see how the tapered gibs fit together... Please see picture below on the dove tail i have one side of the tapered gib hit the complete surface on the other side its at an angle that doesn't match the dovetail... it it correct that both surface need to touch each other over the whole surface area?



Just for reference...

[691175002]

Both sides of the gib should make complete contact with their corresponding surfaces.

The misalignment could come from several sources - the dovetails could be at incorrect angles or the gib might be thinner on one edge.

It looks like you are going to have to remove a lot of material to fix the problem so the gib will need to be shimmed (or remade).



I would recommend worrying about the gibs last since scraping the dovetails will change how the gib fits.