Technical Best Filler for Banjo Axle Tubes?

I’m getting ready to put my banjo rear back together and figure now will be the easiest time to fix the minor pitting in the axle tubes and paint them. I just got them back from sandblasting and they have some minor pits. Nothing too bad at all but enough to need some treatment I think. I was going to use Bondo but was worried about the heat. I’m not really sure how hot the axle tubes get under normal conditions. What would you all recommend?

 

Bondo is what I would use. Easy to work with. I wouldn't worry about the heat. I have used it on rocker covers with good success before.

 

That makes me more comfortable for sure. Thanks @porknbeaner.

 

Have you ever heard of a product called All Metal?
Goes on like bondo supposed to be pretty durable.

 

Good grade filler is fine, but decide what the finish level will be. Do you plan to grind off the weld seams and have a ready to chrome smooth finish or just as they left the factory with all the forging marks? "Was pitted then Bondoed " look is easy to spot if done poorly. Bob

 

I have heard of that. Just not sure I need the extra strength. Seems like Bondo may be easier to work with.

I’m definitely going to keep the weld seam and other factory marks. Just looking to smooth the other areas for a nice glossy paint.

 

Use Good Quality body filler like other have said

 

are you painting it high gloss black?

 

You'll be fine with Bondo. If the rear get's hot enough to melt or whatever your concern is about the filler, you have bigger issues.

 

This stuff I swear by... Hardens quick, an sand's better than Anything on the market imo...

 

I would spray it with a few coats of high build primer. If the pits are minor filler and/or putty is going to be more trouble than it's worth.

 

The high build primer will give you a nice uniform surface finish.

 

After looking closer it's not what we have in the North East rust wise , Couple Good coats of 2K urethane primer would probably do it also

 

Yes, primer would give a more uniform finish, with less work. Bob

 

I blew the photo up, the pits look like they need more than just primer. primer COULD fill them, but plastic filler will be easier and faster and most of it can be done with a D.A.. then prime and sand again [for high gloss black].

 

Here’s a better pic. I think I need some filler but defer to those with more experience than me. I am planning on a high gloss black finish.

 

While on the topic, how does a guy block the filler with out getting an irregular surface on something round like that?

 

Round sandpaper.But really one of those foam sand pads.

 

If you use long strips of paper it is the same motion as a rag polishing your shoes. Bob

 

Epoxy prime. Plastic filler not finish glaze. 2 part primer sanded to perfection.
Under the car is a rough environment.

 

I would sand that out with a D.A sander, using the steel surface as a guide, get it close with 80 then finish with 180. the beauty of "round" is you can not see a wave/dent around a corner. the trick to getting it to look right, as alluded to by The37kid, is finishing/blending the edges, so the whole surface has the same finish. this would be done by hand. prime and block out any blemishes.