Crankcase repair

[mheim1]

I'm in the process of rebuilding a 066 and plan to powder coat the crankcase.
As expected, the case has some corrosion (pitting) that I want to smooth out first (have to post some pictures later).
Anyhow, does anyone have first hand experience with either Thermobond 3 or Lab Metal (don't think I need to use Hi Temp Lab Metal) or a better solution?
Thanks.

 

[blsnelling]

Do the holes go through? If not, just clean it up good.

 

[Scooterbum]

Lab Metal works fine. Just do a good wash first. I use an Iron Phosphate solution but you could use just about any solvent that will clean up any oil residue.

 

[jbighump]

could one use filler putty intended for auto body work???

 

[blsnelling]

Are we talking internally or externally? Exposed to fuel, or not?

 

[mheim1]

Do the holes go through? If not, just clean it up good.

No. They just look rough; I could just powder over it, but want to try to make it look better.

could one use filler putty intended for auto body work???

No. It has to be electrically conductive for the powder coating.

 

[mheim1]

Are we talking internally or externally? Exposed to fuel, or not?

External, mainly at the bottom.

 

[Scooterbum]

You can't use body filler because as soon as you do a bake it will crack and fall out.

You need a high temp filler.

 

[glock37]

you could try those alum welding rods they show on tv

post a pic of the corrision on the case

before you powder it after cleaning dry it in oven to make sure all moisture is of it

tape off the places you dont want powdered with special tape

plug all screw holes with screws or special plugs that dont melt

powder the case halves and coat with a clear

I just did mine its in Masterminds 041 super rebuild thread

brother owns powder coat co

once powdered if you dont like it your in for a time getting it back off so do it right the first time

 

[mheim1]

Picked up some Lab Metal on my way home (another $40 down the drain).
Here is a picture of the corrosion; not to bad, just a little rough.

What tape is recommended for powder coating?

 

[Scooterbum]

Picked up some Lab Metal on my way home (another $40 down the drain).
Here is a picture of the corrosion; not to bad, just a little rough.

What tape is recommended for powder coating?

Lab metal goes a long way. Use sparingly, you have a real short working time.They also have a solvent that goes with it for when it starts to dry up in the can.

I use a high temp tape from Columbia Coatings. Or if your shooting cold you can just use some blue fineline type and remove before you bake.

A lot of times when there's a lot of crevices to get in I will shoot at bake temperature.No cage effect that way.

 

[glock37]

Wow thats some pits in there

how hard is it to get another case ?

Its a green tape that is used to mask places off it comes in all kinds of widthes

I'll have to ask Brother where and what he uses , even at 400 degrees this stuff stayes sticky

aluminum is always better to heat before powder because of out gasing of the metal

Welcome to Electro-Kote - Home

 

[mheim1]

Update

Applied some of the Lab Metal:

Sanded it down:

Not bad at all.
It doesn't look smooth in the picture, but it actually is (way better than before).
Now I have to decide on a color and order some powder. What do you guys think?
Off White, Grey White, Bright Yellow, Blue,...?

 

[064AV]

aluminum is always better to heat before powder because of out gasing of the metal

Stihl cases (at least an 066) are magnesium. Thought it was worth mentioning.

Just today I set some 064 filings/ shavings on fire Mag's fun

 

[064AV]

crankcase repair ( STIHL )

The " magical welding" rods sold on tv are for brazing. Until I researched them, I really did not realize the definitions of welding vs. brazing vs. soldering. It isabout temperature.

The reason I bring it up is that I purchased some alloy brazing rods, but I'd like some info on welding (tig).

Any recommendations for appropriate rod? Flux ( you can actually has weld Al and Mg) ?

Are STIHL handlebars also magnesium?

 

[glock37]

I Never heard of that stuff

if it filled the dimples i geuss give it a try

I just wonder if it will take the temp of Powdering

325 -400 degrees for 15-20 min

we shall see

For the costs of a replacement 066 crankcase

Nice Job on the fill and sand , brings you back to doing body work on cars .

 

[Scooterbum]

I've taken to 600 degrees and it holds well doing ceramic work.

Do your cure at 325, no higher. I always bake aluminum and Mag at a lower temp to cut down on the chances of warping. Just double your cure time.When done just crack the door on the oven and let it cool down real slow.

Post some pics when she's done.

 

[mheim1]

I think I'll go with some traditional Off White on the case and all the metal parts.
In the meantime, I'll have to work on the plastic pieces.
The Orange will get a light sanding (can you hit it with some glass beads??) and a clear-coat, the "white" handle :msp_confused:
No Idea.
Open to suggestions.

 

[Trx250r180]

on the plastic ive seen some on here where they wet sanded the oxidation off then applied an automotive clear coat ,look brand new in the pictures on the handle id just clean it and scrub it with castrol super clean or zep wheel acid if real stained ,i usually watch ebay for the plastics ,i picked up a brand new 660 filter cover for 20 bucks ,and new top covers ive picked up in the 30-50 range just depends how nice you want it too look and how much willing to spend on the saw vs elbow grease

 

[Scooterbum]

I've done them both in a High gloss white and pearl white.I liked the later better.Painted the handle to match.
Use a good adhesive promoter like they use for automotive bumpers.You can get it at any autobody supply.