Silent block bushing and powder coat

[A10 Tim]

Hi all,
       is it possible to powder coat the swinging arm with the silent block bushing still in place,or would they have to be removed first because of the heat involved.
Many thanks for your comments.
Nice bike in your picture.

[Brian]

No, the silentblocs have to be removed. Powdercoating is baked at around 180° C and the rubber will melt.

[A10 Tim]

Hi Brian,
          they will have to come out then, I think I will farm that one out, looks like a difficult job to me.
Cheers Brian for the much needed info.
               

[RichardL]

Otherwise, you could make the swing arm the one piece you paint with spray cans.

Richard L.

[A10 Tim]

Hi Richard,
              As the bushes are in very good condition I think I will do that, paint the swing arm and powder coat the frame.
Many thanks Richard

[Greybeard]

The bits on my bike I sprayed with rattle-cans have not done well after three years. The plunger trunions were damaged by my careless spannering, the plunger spring shrouds were scratched during assembly and the top fork yoke from my bunch of keys. In fact I've replaced the shrouds with new ones that came powder coated, (care of Beezermac AKA Andrew Guttman). Other parts I've been repainting with a good quality camel hair brush. I used Halfords cellulose primer/undercoat with their acrylic top coat. I'm very happy with the result.

The frame was powder coated and it's a great tough finish.

I guess if your swing arm finish doesn't hold out well you can get it powder coated later.

[bsa-bill]

The frame was powder coated and it's a great tough finish.

Certainly is but it is not not a hard finish so polish only with non abrasive wax

removing the bushes is not too difficult, I removed mine by drilling out most of the rubber with a metal drill bit but one of those scrolling bits that cut up the length of the bit might work well, the inner metal tube can then be removed without much effort grab it with thin jawed vise grips and just twist and pull.
The other metal sleeve I cut up it's length with a padsaw ( one of today's reciprocating saws would be ideal I think), then collapse one of the cut ends in with a hammer and punch or chisel, it can then be wiggled out.
PS no need to cut right through with the pad saw but if you do one small mark in there is not going to affect any thing (affect - effect never could sort them out, must Google them sometime)

[Greybeard]

...affect - effect never could sort them out...

Same here. This might just confuse more: https://goo.gl/tRsvyB

[tommo903]

Tim,
Whilst I agree with bsa-bill, the best solution is to remove all items before painting, however, the other option you have would be to have the swinging arm painted with '2 pack' by a painter. It may not be as tough as powder coat but far more resilient than spray cans. I believe it's also low heat bake but not sure of the temperature, however, any decent painter will advise.

Steve

[Billybream]

My frame complete with swingarm still assembled was painted with 2 pack and oven cured, from memory I think it's approx. 55C with no damage caused to bushes.
Will agree 2 pack not as good as powder coat or similar process but has stood up well. 2 pack seems easy to chip during bike reassembly so you need masking tape for protection or plenty of grease. 2 pack finish is excellent.

[RichardL]

Due respect to Bill, but replacing good bushes (for the sake of paint) for anyting other than a concourse restoration seems like waaay too much trouble. Getting the old ones out might be considered fairly basic (but still a hassle) but putting in new ones that have some history of oversized ODs can be a difficult task. 

Richard L.

[coater87]

Due respect to Bill, but replacing good bushes (for the sake of paint) for anyting other than a concourse restoration seems like waaay too much trouble. Getting the old ones out might be considered fairly basic (but still a hassle) but putting in new ones that have some history of oversized ODs can be a difficult task. 

Richard L.

 And thats no joke. Especially if you have a 70 ton shop press available that raises and lowers with a push button.

 I get mine out by welding little bits of round bar into the bores, then pushing them out. Originals out in a few minutes.

 Then I did not measure the outside diameter on the new ones, just centered one up and and push it in.

 The press gave a tiny grunt, and new bushing mushroomed over.

 After very careful measurement with nice tools, new bushings are oversized .006 to .011 and thats two totally different looking types from two suppliers.

 Its easy enought to turn the OD down on a lathe, as long as you are aware of the problem.

 Lee

 Added this. The OD of the bushing should be .001 larger than the bore for a tight press fit (measure your bore carefully, and many different spots. Average out your measure and thats your bore diameter). Larger than that, and you are going to have a lot of trouble getting them in. Once its painted or powder coated, adding heat to the swing arm to ease a tight press is out.

[DuncanF]

Thanks to the advice given on this site, got mine out in 20 mins today. I did use my die grinder to weaken the outer sleeve, after melting the inners out though, instead of the dremel suggested.

[bsa-bill]

thanks for the "due respect" guys,

 I was assuming the powder coat was the preferred option, another thing that swayed me to remove my silent blocks was how can you judge how good they are when you can only see two ends of fifty year old rubber, you can try wiggling the S/A but mostly that just shows wear in the holes the rod goes through, OTOH they don't move/twist much anyway so maybe do have a life measured in centuries

[Triton Thrasher]

you can try wiggling the S/A but mostly that just shows wear in the holes the rod goes through,

Tjere won't be movement or wear, between the rod and holes, when it's assembled properly.