Warping Commando frame in Powdercoating

Could Commando frames be warped in a powdercoating oven? I wouldn't worry too much about a Featherbed, but everything about the Commando frame is so thin, especially the headstock. I checked a frame that I have and the there's about ten thou oval. This could have been caused by the welding and has always been there. No big deal probably. One powdercoater told me that he warns people that bring in aircooled cylinders that have already been bored and honed that he's not responsible if they're not round when they get them back. He says powdercoat'em first.

BPatton
I had mine powdercoated and it seems to go OK...don't think it is warped.
Had several featherbeds done without trouble too.
Stu

Powdercoating will not hurt a Commando frame, or any other frame.

Had my frame powder coated in 1998 ('72 750) and have put on over 24,000 miles since. Always has handled very well, so I don't suspect any warp.

David

bpatton said:

One powdercoater told me that he warns people that bring in aircooled cylinders that have already been bored and honed that he's not responsible if they're not round when they get them back. He says powdercoat'em first.

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Slight diversion but I would warn against powder coating aircooled barrels.

1. powder coat goes on very thick and will insulate the barrel far more than regular paint or stove enamel not good if you're air cooled
2. It's applied electrostatically which means on heavily finned barrels the charge all collects at tip of the fin giving an even heavier build up than normal there and poor penetration deep into the finning.
3. Newly rebored engines run hot

Combination of a new bore and powder is not good - I know this from experience, mine overheated during running and I had to start all over. Not a cheap lesson.

Interesting question on the frame - is there any heat in the powder coating process? If there isn't then it is hard to imagine where any warping could come from. As far as i know that actual coating is a cold process but is there a curing/baking type finishing process? Anyway i have been wondering too...
I had my frame coated along with a rewire and the fitting of a number of bits i had bought and not fitted over the last few years - all by a shop which specialises on Nortons. After getting the bike back and with not much riding I found the spring on the Dave Taylor head steady (which i have had for a few years without issue) had broken. When fitting the replacement it was obvious why - the head is no longer centred in the frame so that one side of the spring is under much more tension than the other.
I haven't started playing yet to work out why but frame straightness is an obvious query.

ntst8 said:

Interesting question on the frame - is there any heat in the powder coating process? If there isn't then it is hard to imagine where any warping could come from. As far as i know that actual coating is a cold process but is there a curing/baking type finishing process? Anyway i have been wondering too...

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Coating is at room temperature. Curing is in an oven at approx. 425˚ F for less than an hour (IIRC). I've done it at home.

I wasn't really too worried about the general dimensions of the frame as much as the headstock in particular. Has anyone checked their frame to see if it's round or oval where the bearings go in? A snap gauge or a caliper would do it. Mine's out by ten thou, and I wonder if that's significant. That is for tapered rollers.

Fred at Old Brits goes into great detail on preparation if you are going to powdercoat a frame or anything that's got to have reliable fastenings. The stuff's so thick and soft that you're just asking for it if you try to bolt something to it. The cradle's a perfect example.