MWF FEED
26th April 2020, 01:40 AM
Making some new blade drive plates for my mower as the old ones were flogged out.
Shaft is 20mm diam with a 4mm key but since I've got the opportunity I'd like to make the new ones a press fit to help stop them moving.
New plates are 16mm mild steel (old ones were cast aluminium).
I've looked at the fits and tolerances in my Engineers Black Book and think I've managed to get my head around it.
If I've got it right, for a "Medium Drive Fit (Press Fit)" it works out to be from 0.014mm to 0.048mm interference between the shaft and bore.
But the "Force Fit" range only changes by 0.006mm more - from 0.020-0.054mm interference.
I'm thinking I aim for 0.03mm, but they're just numbers to me - I've got no feel for how tight it will be.
I want them to be as tight as I can practically get them, but I've only got a 6T supercrap press so I don't want to snooker myself by making them TOO tight and getting them stuck half way on.
Can anyone give me some feedback on whether 0.03mm interference is overdoing it or not?
Steve
Read the full thread at metalworkforums.com... (https://metalworkforums.com/showthread.php?t=204919&goto=newpost)
Shaft is 20mm diam with a 4mm key but since I've got the opportunity I'd like to make the new ones a press fit to help stop them moving.
New plates are 16mm mild steel (old ones were cast aluminium).
I've looked at the fits and tolerances in my Engineers Black Book and think I've managed to get my head around it.
If I've got it right, for a "Medium Drive Fit (Press Fit)" it works out to be from 0.014mm to 0.048mm interference between the shaft and bore.
But the "Force Fit" range only changes by 0.006mm more - from 0.020-0.054mm interference.
I'm thinking I aim for 0.03mm, but they're just numbers to me - I've got no feel for how tight it will be.
I want them to be as tight as I can practically get them, but I've only got a 6T supercrap press so I don't want to snooker myself by making them TOO tight and getting them stuck half way on.
Can anyone give me some feedback on whether 0.03mm interference is overdoing it or not?
Steve
Read the full thread at metalworkforums.com... (https://metalworkforums.com/showthread.php?t=204919&goto=newpost)