Topic: Powder coating clean up

[The Gurg]

Frame cb750K5

Powder coater did a descent job. Most bolt holes we’re plugged. Seems like they have a silver gritty quality to the bolt holes though. Read other posts that I should run a tap. Does that apply for powder coated bolt holes or also to get rid of the silvery coating? I can run bolts down the holes with the silvery coating, but it feels like 90ish inch pounds of resistance. Don’t want to snap a bolt, but seems like it’d be fine. Is that ok?

Was able to run the center stand’s pivot pipe through even though that c shaped holes were missed and not plugged and do have powder coating. It’s a tight fit, but didn’t feel like I was forcing it. Should that be pulled and the powder coating removed. Or is that ok? The center stand is connected to the frame by those two c-shaped holes that don’t connect and then bolts pull the c tight. Haven’t torques those bolts yet.

How would you remove powder coating from non-threaded holes?

[Don R]

 The grit may be the blasting media they cleaned it with before coating. I would flush and blow them clean before running a thread chaser through. Center stand should be ok, they're pretty forgiving. Be careful with a tap, some of the guys say they will remove good material.

[The Gurg]

I’d have to go pick up some chase taps. A 6mm and 8mm should cover the frame holes right?

[The Gurg]

Don-
On the thread chaser, do you mean “can” or “should” use a thread chaser.

Don’t want to break a bolt, but on the flip side don’t want to accidentally cross thread a thread chaser.

Is there a point of resistance (like below 50 inch pounds is fine, but above is not) where you get out a thread chaser or is it the kind of thing that if it’s not buttery smooth you get out the thread chaser?

[madmtnmotors]

Clean the threads with a tap. There is excess foreign material in there that must be removed. Thread restorer tools work well in aluminum to prevent removal of too much soft aluminum, but threaded holes in the frame will be steel. Clean the threads in the frame with a regular tap and clean the hole after you're done with the tap with compressed air or even some electrical contact cleaner. Brake cleaner or carb cleaner is pretty aggressive if you get it on any painted surfaces. I know yours is powder coated but I imagine there will be something that is painted and you don't want to realize it after it's too late.

[754]

If you don't clean it... you run the risk of it seizing after install. It will probably go in, but will it come out ?
 Also I would run a light smear of oil or wax on the bolt threads.

[The Gurg]

754-
Thanks for providing the reasoning! Always help me improve to know the why!

Everyone-
All the frame holes (including holes in the swing arm for the stoppers) should be standard coarse right M6 x 1.00 and M8 x 1.25? Can I use a pitch gauge for holes?

Shock mounts (post a week or so ago) was M10 x 1.25 Fine, so that was a bit of a surprise.

[bryanj]

You can use a gauge on holes but its not easy, easier to see which bolt will start easy and gauge that

[754]

You know if you got spare bolts around , you could grind a notch or two,  grease the bolt and it might clean the thread, they just got stuff in them, not smashed or anything.
 I should caution,  if you have any stainless  fasteners, running one in dry to check, can easily lead to seizure..

[The Gurg]

Was working on the front forks. Coming back to this. Looking at running the tap today or tomorrow.

Ordered a set and tried to cancel them after I picked up a set. Canceling the order didn’t work. Now I have two sets. See photo.

1.) Drillco HSS hand taps bright
2.) ARP thread cleaning chaser tap and a thread cleaning tap

Which should I use first?

[madmtnmotors]

Clean the threads with a tap. There is excess foreign material in there that must be removed. Thread restorer tools work well in aluminum to prevent removal of too much soft aluminum, but threaded holes in the frame will be steel. Clean the threads in the frame with a regular tap and clean the hole after you're done with the tap with compressed air or even some electrical contact cleaner. Brake cleaner or carb cleaner is pretty aggressive if you get it on any painted surfaces. I know yours is powder coated but I imagine there will be something that is painted and you don't want to realize it after it's too late.

[The Gurg]

Yeah, I remembered that I wasn’t supposed to use a chaser. Just wasn’t sure if the thread cleaning tap fell into the chaser category or not. They have chasers that are just bolts. Then there’s a bottoming, plug and taper taps. The drillco are plug taps. Assuming that a plug tap would be fine (maybe taper would be the best for the application), it’s the high speed steel part we care about (because the frame is steel)? So I’d say use the drillco hss plug taps. Am I’m on the right track?

And saw some videos that I go a half turn than back a quarter with plenty of oil? Do I need to go back and forth cleaning threads? I know it’s important cutting new threads so the chips don’t build up, doesn’t seem like it’d matter here.

Appreciate that your tamtf!

[madmtnmotors]

A 1/4 turn to "clear the chips" with oil is for aggressive cutting, such as when cutting new threads in raw material. You are merely "cleaning up" contaminated threads that may also have some distress/misshape from exposure to elements, powder coat, and/or heavy handed PO's. Either one will work, I'm merely suggesting you use the less aggressive approach at first. Less chance of buggering something up. 

Not sure what a "thread chaser" is either. Sounds less aggressive than a tap but whether it be a "thread chaser", "thread restorer", or a plain old "tap" they all will work, it's just the more aggressive cutters (i.e. tap) have a greater chance of causing damage if used carelessly, especially in softer material.

[The Gurg]

Ah ok, I think I’m tracking now, sounds like your saying go with the arp cleaning taps. Because they’ll be gentler than the drillco hss.