Author Topic: Powder coating vs Stove enamelling  (Read 879 times)

Powder coating vs Stove enamelling
« on: February 09, 2020, 04:42:45 pm »
All,

Mrs hatler would like to have her old Orange P7 frame coloured pink (promotional reasons).

There's an outfit near us (Jura Spray) which I've used before for a variety of odds and sods. Quality seems pretty good.

If I strip all the parts off the bike and hand it over to them, what do I need to consider ?
What should I do to prepare the frame (if anything) ?
Also, what's the panel's preference, powder coating or stove enamelling ?

Many thanks, as ever, for all input.
Rust never sleeps

LittleWheelsandBig

  • Whimsy Rider
Re: Powder coating vs Stove enamelling
« Reply #1 on: February 09, 2020, 04:45:31 pm »
Put sacrificial bolts, etc. into any threads. It is a bugger getting powdercoat out of threads. Tape up any interfaces with pressfit components e.g. headsets.
Wheel meet again, don't know where, don't know when...

Re: Powder coating vs Stove enamelling
« Reply #2 on: February 09, 2020, 05:18:53 pm »
And cover bottom bracket threads.
I am often asked, what does YOAV stand for? It stands for Yoav On A Velo

Socks

  • FFCT rally, France 2012
Re: Powder coating vs Stove enamelling
« Reply #3 on: February 09, 2020, 05:19:22 pm »
I've used powder coating on several vintage bike restorations.  Good results and there is usually the option of an additional protective clear finish.  You do have to make sure any traces of oil or grease are removed beforehand, so that it coats smoothly. 


LittleWheelsandBig

  • Whimsy Rider
Re: Powder coating vs Stove enamelling
« Reply #4 on: February 10, 2020, 06:26:30 am »
Some types of transfers don’t stick to powdercoat.
Wheel meet again, don't know where, don't know when...

robgul

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Re: Powder coating vs Stove enamelling
« Reply #5 on: February 10, 2020, 07:44:07 am »
To answer the question : powdercoat vs stove enamel  - chalk and cheese on cost and finish.     In both cases the original finish needs to be removed - either grit blast or chemical.    From experience with probably 20 or so refinishing jobs get the whole job done professionally - don't try paint stripper etc.

If you are wanting an original finish masterpiece then the expensive stove enamel is the bee's knees - for a good result at a fraction of the price then powdercoat does a good job, especially if you have the colour and then the clear overcoat.

AND as Dave says - make sure you put old bolts in any threaded holes and old-style BB cups in the shell to make sure the finish (especially powdercoat which is quite thick) doesn't clog the threads.  The powdercoater will normally mask the head tube and fork crown.

Rob

Re: Powder coating vs Stove enamelling
« Reply #6 on: February 10, 2020, 07:49:57 pm »
Brilliant !  Thank you all.

Time to fire up a couple of quotes methinks.
Rust never sleeps

Re: Powder coating vs Stove enamelling
« Reply #7 on: February 10, 2020, 07:56:23 pm »
I had an old frame powder coated. Its brilliant. Much much tougher than enamel and perfectly nice finish, unless you want some sort of showroom piece.

Re: Powder coating vs Stove enamelling
« Reply #8 on: February 11, 2020, 08:04:19 pm »
roughly, in terms of toughness;

Good powder coat > more basic powder coat > two-pack solvent based automotive paint > 'enamel' offered by frame refinishers > almost anything you can buy in a rattle can.

Good paint finishes of any type have good prep on the frame first and use corrosion-resisting undercoats; that is where the longevity of the paint finish really comes from.

The best looking finishes on bike frames are still not powder coats, but good powder coats are not at all bad these days.

cheers

guidon

  • formerly known as cyclone
Re: Powder coating vs Stove enamelling
« Reply #9 on: February 12, 2020, 10:02:29 pm »
Try to explain to them that cromoly tubing is not that tough no carrying about on a fork lift, for example....Great powdercoat but not so the dents in the tubes  :(

Re: Powder coating vs Stove enamelling
« Reply #10 on: February 12, 2020, 10:53:28 pm »
Most commonly,  powder coating will be polyester or polyurethane based. Neither of these take well to adhesives.
As has been mentioned elsewhere, you may struggle to get stickers / transfers to stay in place.
I had an aluminium frame (not bicycle) powder coated at one time. We then needed to deploy some Tonka double sided tape to attach something to it.
The advice of 3M's industrial tapes division was sought, and adhered to (can you see what I did there?).
It was rubbish, and would not hold. Nor would anything else.
Eventually, I had to design, and have manufactured, a spring-clip fitting, to mechanically attach whatever it was we were trying to attach. (Fabric covered foamex panels, as I recall).
Of course, you may decide not to have stickers.
I'm not aware of similar problems existing with stove-enamel.

Re: Powder coating vs Stove enamelling
« Reply #11 on: February 12, 2020, 11:17:14 pm »
roughly, in terms of toughness;

Good powder coat > more basic powder coat > two-pack solvent based automotive paint > 'enamel' offered by frame refinishers > almost anything you can buy in a rattle can.

cheers
Is DuPont Imron of the type highlighted above?
My current Thorn is painted with it and it's become my favorite finish, it's tougher than the powder coats I've had (Though I know they're not all the same) yet still has a deep gloss.  The one minor scrape it has in two years hasn't gone to bare metal, so probably a well prepped frame, it still looks like new. 
I had a frame previously with some sort of polyurethane finish, it was soft and scuffed quite easily yet didn't chip, it ended up looking a bit scruffy but still well protected.  I'd have gone for it again when it needed re-spraying after a repair but they were no longer offering it.
I wouldn't trust a powder coater unless I'd seen some similar examples of their work, those I've seen have been very variable, from almost paint like to a dull industrial look.

Re: Powder coating vs Stove enamelling
« Reply #12 on: February 13, 2020, 01:55:18 am »
IMRON is the tradename for a range of two-part polyurethane finishes. They vary in make-up depending on the VOC, but they are one of the harder types of paint that you can get. 

cheers

Re: Powder coating vs Stove enamelling
« Reply #13 on: February 13, 2020, 07:04:06 am »
Is the frame valuable and will you need to display the frame number at a later date? My Harry Quinn was powder coated and I'm pleased with the result, BUT the distinctive frame numbers are now difficult to make out because of the thickness of the coating. This is important on a Harry Quinn.

I had no problems attaching transfers onto my frame and I also lacquered them afterwards without issue.
Haggerty F, Haggerty R, Tomkins, Noble, Carrick, Robson, Crapper, Dewhurst, Macintyre, Treadmore, Davitt.

Gattopardo

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Re: Powder coating vs Stove enamelling
« Reply #14 on: February 14, 2020, 01:47:28 pm »
Thought stove enameling was not good for a frame as the frame has to be baked at over 120-150c is that good for certain frames?

Re: Powder coating vs Stove enamelling
« Reply #15 on: February 14, 2020, 07:26:09 pm »
Any steel frame will be fine - even silver solder has a flow point of several hundred degrees C. I wouldn't do it with a carbon one or anything that is bonded together.

Re: Powder coating vs Stove enamelling
« Reply #16 on: February 14, 2020, 08:53:32 pm »
Wet paint, every time.  Most powdercoating I've seen is rubbish.  It won't take a polish, is orange-peely and the steel corrodes briiliantly underneath.  Factory stuff on new bikes is good but will include a decent phosphating and a lacquer.
Never tell me the odds.