Prepping a Bike Frame for Powder Coating with Logos

Step 4 Adhere the Logos

Once formed, the logos need to be bonded to the frame. The difficulty with this part is the choice of the adhesive given that the powder coater will cure the frame at above 400 degrees F. Most epoxies burn at these temperatures, but standard JB weld does just fine up to 500 F. So, despite a wonderful selection of aluminum adhesives - Hysol, 3M Aluminum Series....etc - I choose JB weld.

The best way to affix the logos would likely have been to vacuum bag them to the frame. I was too lazy for this, so I used a clamp and clear packing tape. The nice thing about clear packing tape is that it will not bond to anything (that I have found yet). This makes the clean up easy.

Try to put a small amount of epoxy on the logos as you adhere them to minimize the finish work after they cure. I found that the finish work (getting rid of excess resin) was best done with a dremel.

Comments

[reinovator]

You can add metal filings to the 'JB weld' and it will conduct and adhere. Also it's a static charge which holds the power to the surface not just an electrical charge the key is melting point of the glue. but this is just my experience others may differ.

[skrubol]

The biggest issue I've heard with JB Weld for using with powder coat is that it's not very electrically conductive. I guess not a problem when using it as an adhesive (you did it,) but as a filler I've heard the powder won't stick to it.

[corwin]

There was a section of the frame that had been cut out by Specialized to prevent anyone from riding the frame because the dropouts where not straight. I did not take any pictures of this, so I could not include it in the instructable. However, I straightened the dropouts (filing) and machined an elliptical part to bridge the gap. The point of all this is that I faired in the gap with JB weld as well, and the powder coating stuck just fine.... although, I do not know if the powder coater prepped the surface with something once I gave him the frame.

[Handsy]

Since JB contains steel powder, I think it worked itself out. Nice instructable!

[Pkranger88]

Any time you apply a non-electrically conductive material prior to powder coating you have to spray or apply a conductive paint to prep the surface.
http://www.caswellplating.com/kits/silvaspray.html
It can be expensive if you're only doing it once, but powder shops should have the spray