Stiffening A Mini Lathe Bed

Ok update!:

I put a 1" dia mild steel bar drilled a center hole and moved the bar all the out..(tail stock is at the end of bed) put indicator in my tool post with left hand grabbed back to headstock right hand tail stock and i tried to twist..... could hardly see it move maybe .0005"! ok good

now i turned down the bar to clean it up took a few passes then a few thou pass and measured less then.0005" taper from end to end but of an 8" cut lenght bar ....actually it was prob dead on but this steel is such quality (teary) just because of that i was getting a dead on reading and the .0005" difference.... ...this coincides with the .0005" twist or not!? I did not shim anything! I just bolted those 2..... 1/4"1045 steel plates on the bottom looks like this is an easy mod still portable and fun! I did have the tail stock center still in while while turn down the bar this could have influenced my reading but I doubt it.....no concrete needed!

Lawrence
 
Last edited:
Well done then! Job done!
I think your lathe is solid as a rock! Is it a 7x12 lathe or bigger?
 
its a micromark 7x16...I will do more tests its very hot out today!
 
Although on the other side of the globe weather is similar here!
 
petcnc said:
Lawrence hi
To measure flexibility just fix a bar in between centers, support the TDI to the toolpost move the carriage all the way towards the tailstock touch the bar with the TDI and zero it (see photo)

View attachment 130444

Now with your left hand hold headstock and with your right hand hold tailstock. Pull with one hand and push with the other while reading the measurement on TDI.
Reverse the push-pull procedure and note the new measurement.
In my case the measurement was + 0.25 and -0.25 mm accordingly.
Needless to say that with a bar that has the maximum length the lathe can handle, you will take the most accurate data.

Petros
Click to expand...
Petros, It would seem to me that to measure flexing of the lathe you would not want to constrain it with the tailstock center. By doing so, the bar will follow the tailstock as does the bed twist. The bar should be floating, secured only by the headstock chuck. In that way, you will be measuring true flex relative to the headstock.

Using your method, I see flex of about .0002" on my G0602 when applying an estimated 100 lbs. of force to the tailstock. With the bar floating, I see about 10x that flex. Also, since you are measuring flex in the bed relative to the tailstock, I believe that the measurement will be the greatest about midway between the headstock and tailstock support.
 
RJ is correct without the tailstock supporting the bar I get about 10thou:(:(:(:(
 
Rj must be right,
It has been some time since I did the test on mine to recall all details!
Age does not come alone!!!
Sorry to mislead you Lawrence!

Petros
(Edit) RJ is wright as I did it this way initially! I desribed the procedure to may 1st post!!!
 
Last edited:
all good petros, we live and learn and make mistakes! no one is an island ;)
 
Thank you Lawrence I have corrected the previous post that desribed the procedure!!

I have learned my lesson! Dont rush! recall all details before you make a fool of yourself

Petros
 
Nah no fool sir....real good information ...your idea made me do mine.... although different in approach I like it...

now what to do I need a new belt for my micromark 7x16 its different then the regular 7x lathes
 
You must log in or register to reply here.
Back
Top