Polishing your lower unit

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Jeffmaturo

Jeffmaturo

Well-Known Member
Joined
Jan 20, 2015
Messages
547
What do most of you do to polish your lower unit including the skeg?

  • Do you sand the lower first?
  • If so what grit do you use?
  • What type of polish do you use?


Are most lowers made out of pot metal?
 
Cant answer your polishing question, but Im curious to know what brand lower and what class your running it in ?
 
Me, well I smooth out casting with 400g wet and dry, plenty of water. Then might go 800g and a quick go of Brasso to shine it up a little
 
Jeffmaturo said:
Andy Greene said:
Cant answer your polishing question, but Im curious to know what brand lower and what class your running it in ?
Click to expand...

It is an os and I run it in stock....
Click to expand...
Careful, I have seen people called out over less in stock , just sayin
default_ph34r.png
 
The higher you take the steps of sand paper the easier it will be to polish, luster lace is a great polish works on anything
 
Randell Doane said:
Jeffmaturo said:
Andy Greene said:
Cant answer your polishing question, but Im curious to know what brand lower and what class your running it in ?
Click to expand...

It is an os and I run it in stock....
Click to expand...
I'm not sure this is allowed in the stock class...
Click to expand...
Sadly the advantage gained by polishing the lower isnt enough to stand hands and feet above the unpolished lowers- yet somehow- it can be considered a gain in performance if you spank the other " stock " boats with un polished lowers. Similar to someone protesting taking the blue anodizing off of a " stock " cooling jacket. Not trying to stir the pot here- SIMPLY REMINDING EVERYONE of what can and cant be evaluated as NOT STOCK - It only takes one prick .
 
Last edited by a moderator:
Andy Greene said:
Randell Doane said:
Jeffmaturo said:
Andy Greene said:
Cant answer your polishing question, but Im curious to know what brand lower and what class your running it in ?
Click to expand...

It is an os and I run it in stock....
Click to expand...
I'm not sure this is allowed in the stock class...
Click to expand...
Sadly the advantage gained by polishing the lower isnt enough to stand hands and feet above the unpolished lowers- yet somehow- it can be considered a gain in performance if you spank the other " stock " boats with un polished lowers. Similar to someone protesting taking the blue anodizing off of a " stock " cooling jacket. Not trying to stir the pot here- SIMPLY REMINDING EVERYONE of what can and cant be evaluated as NOT STOCK - It only takes one prick .
Click to expand...
Are you implying that you are allowed to polish the lowers of stock outboards? Is this in NAMBA or IMPBA or both? I really don't know myself so maybe someone else does
 
In NAMBA, you can polish the lower unit in the Stock Classes. You can also sharpen, polish, and modify the shape of the skeg. However, you cannot increase the size of the skeg. The IMPBA rule book probably has some type of similar language regarding the lower units.

I've probably raced model outboards as long as anyone on IW and haven't spent any time polishing lower units. However, I've spent time sharpening and changing the shape of the skeg.

JD
 
Stock class what's that.Can't even spell S(ock

Dave
 
Last edited by a moderator:
bob miller said:
are you polishing just for looks or do you feel polishing will make your boat faster ?
Click to expand...
Honestly, I do most things for looks.

I cannot sed how sharpening and sanding off the cadting finish is going to be a negative. UNLESS you have you boat setup perfect on the edge with a standard unit, then Sharpen it up...this can cause the boat to ride differently.

So in other words, it is a tuning option
default_wink.png
 
NAMBA Rules

Section 19.g.ix & .x

ix) Cowlings, shrouds, or painting of the engine case to resemble fullsized
outboard engines will be allowed to promote a more scale-like
appearance.

x) The lower unit may be externally polished or painted, but must
otherwise remain unchanged from the prop shaft housing up.
However, the skeg may be trimmed, thinned, shortened, or removed.
The skeg may not be lengthened or widened.
 
IMPBA rules (referring to B Sport):

  1. [SIZE=10pt]The lower unit below the cavitation plate may be trimmed, sharpened or polished. No material shall be added to the lower unit. [/SIZE]

Looks like I was wrong in both cases, shouldn't be a problem!
 

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