[4]

Using a fly cutter to bore out an aluminum casting

[3]
[10] Like what you see?
Click here to donate to this forum and upgrade your account!

dansawyer

Newbie
Registered
Joined
Jun 13, 2018
Messages
18
Likes
6
#1
The objective is to bore out a 1 1/8 hole in cast aluminum to 1 5/16. The hole is about 1 inch in depth. My plan is to create a centering tool to ensure the casting is aligned and then to bore the hole with a fly cutter. The fly cutter will be tested fist to ensure proper diameter. Given the alignment is correct is this a reasonable approach?
 

bfd

H-M Supporter - Gold Member
Staff member
H-M Supporter - Gold Member ($25)
Joined
Sep 9, 2016
Messages
421
Likes
245
#2
I have used a flycutter to bore a hole. If you are careful and have clearances it will work but it will take time and patience bill
 

benmychree

John York
H-M Supporter - Gold Member ($25)
Joined
Jun 7, 2013
Messages
2,427
Likes
1,820
#3
The reasonable approach, beyond setting the center, is to "cut and try" so far as size is concerned; take a small cut that you know is undersize, cut to that diameter, measure, and take another cut after adjusting the tool out against a dial indicator, until the target diameter is reached.
 

bfd

H-M Supporter - Gold Member
Staff member
H-M Supporter - Gold Member ($25)
Joined
Sep 9, 2016
Messages
421
Likes
245
#4
loosen the screws slightly set a dial indicator on the cutting tip and tap the toolbit out a bit and tighten screws again and take a trial cut. that's where the patience comes in. not a good or easy as a boring head but if you don't have a boring head, do with what you have bill
 

Norseman C.B.

Active Member
Registered
Joined
Dec 21, 2013
Messages
175
Likes
84
#5
Whut them other guys said ........ BTDT !!!! .........:grin:
 

MarkM

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Apr 23, 2017
Messages
269
Likes
197
#6
Once you have centred yourself over the whole. Zero x and y so you can return here. Touch off on an edge of a pc. Of scrap. Centre your spindle over the edge. Now move your spindle over to the size of The radius for the hole size. Mount your flycutter and adjust your cutter until it touches off on your scrap. Now your cutter is set to the size of hole you want. This could be used for your final cut and to be somewhat accurate.
 

Downunder Bob

H-M Supporter - Sustaining Member
Staff member
H-M Platinum Supporter ($50)
Joined
May 16, 2016
Messages
1,016
Likes
410
#7
Yes it will work, but will be difficult to adjust cutter for final dimensions. If your tolerances on dia, are fairly tight, you might want to rethink it.
Can you spring for an adjustable boring head they are not that dear these days.

However if your tolerances are not so important then go for it. As BFD says use a dial indicator to set the tool will help.
 

MarkM

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Apr 23, 2017
Messages
269
Likes
197
#9
There you go! Thx Bill stupac. This video is simialr to what I was talking about. Alot of Automotive, moto, atv, lawn mowers are bored with a flycutter. Usually set and left aside for final dimensions. Nice and rigid and no bar flex. Many ways to skin a cat!
 
[6]
[5] [7]
Top