Reamer size for a light-press fit for .7515dia bushing?

[danielm]

I want a fit that will be remove-friendly....just in case.

 

I'm guessing a .7505 will do. But should I go with a .7510?

 

Mat'l is T6 Alum.

 

Thanks. DM

[crazy^millman]

I would go .7505 in Alum since it will grow some after that.

[Greg_J]

We use to ream with a carbide reamer at .7508 for a good press fit.

[Chris Rizzo]

Removable with what? Fingers, hammer, arbor press, hydraulic?

 

It is getting annodized? That will change your ball game a bit...

 

If not .7505 will be pretty darn snug.

 

.0005 will give you finger-fit.

.0015+ heat & arbor press at that 3/4" size.

[Oppiz]

Unless the hole is deep, have you considered circle pocket or boring? That way you are in control of the end result.

[Müřlıń®]

A half is plenty. If you go a full .001, use a heat gun @ 400 degrees to install them or there is the possibility of shear in aluminum.

[djstedman]

Best way to figure fits at pretty much any size is to use the classes of fit info from the machinery handbook..

 

Since people have gone to the trouble of determining all this information and providing it in a nice format for use its what I always use to determine sizes for fits.. hasn't steered me wrong.. and it eliminates guesswork and over engineering that often hapens designing fixtures etc..

 

Should be able to find the section under allowances and tolerances for fits in MH#26 the important parts start on page 633

[Brad St.]

This conversation is soooo old around here at our work. Press fit starts with size on size and goes from there.

 

What's the bushing material / surface finish / coatings?

 

What's your positional tolerance for the final placement of the bushing?

 

Will you give the bushing a nice lead in or the hole to get a decent alignment started?

 

+1 to djstedman, the handbook has some good information.

 

as for all of my questions don't take them wrong, they are just part of the years of the continual evolvement around here of Engineers re-engineering the physics of reality.... in a nustshell getting a bigger BFH. And I could add alot more to the list...

[Reko]

I would go .7505 in Alum since it will grow some after that.

 

Don't forget, you can vary the size a reamer will cut by using coolant to hold the reamer size... or use cutting oil and you'll get .0002"- .0003" bigger size than the reamer.

[SledGeek]

+1 Brad

 

in addition ..........What is it's function ? Bushing-what kind-oilite? composite? hardened steel? , bearing-what kind ? Steel , plastic ? loads applied- radial, axial?

[Newbeeee™]

1/2 a thou is plenty for press fit.

But depending upon what it is, you can make it easier for yourself by going for a slide fit and using loctite 603. When you want to get it out heat gun or press and it will come out ok.

[Guyinthedesert]

1/2 a thou is plenty for press fit.

But depending upon what it is, you can make it easier for yourself by going for a slide fit and using loctite 603. When you want to get it out heat gun or press and it will come out ok.

 

+1 That's what I do.

[danielm]

Thanks for all the input!

[horsepowered]

The heat is a good sugestion. Another trick I use use to coat the Aluminum with a light oil to help avoid the shearing/galling of the aluminum during the press. I usually shhot for a .001 press.