Jump to content
The mkiv Supra Owners Club

Gearbox painting- lack of planning!


swiftstu

Recommended Posts

Hey gang, I’ve proved once again why I’m not a mechanic...

I spent a lot of time cleaning a gearbox, getting ready for a manual conversion. It’s now amazingly clean.. I’ve popped a few coats of VHT paint on now for some protection and it looks lovely. BUT, the paint now needs curing as it’s all rubby offy.  

Any ideas as to how I could do this??.. I just didn’t give it a thought.

I thought about building a sacrificial fire and getting it to confess, but I have no serious ideas.

thanks!!

Link to comment
Share on other sites

3 hours ago, swiftstu said:

Hey gang, I’ve proved once again why I’m not a mechanic...

I spent a lot of time cleaning a gearbox, getting ready for a manual conversion. It’s now amazingly clean.. I’ve popped a few coats of VHT paint on now for some protection and it looks lovely. BUT, the paint now needs curing as it’s all rubby offy.  

Any ideas as to how I could do this??.. I just didn’t give it a thought.

I thought about building a sacrificial fire and getting it to confess, but I have no serious ideas.

thanks!!

The first thing you did wrong is paint in this weather. Lost of moisture in the air. Then how many coats and how heavy? I believe VHT needs heat to cure once applied to engine parts to

Edited by evinX (see edit history)
Link to comment
Share on other sites

7 hours ago, evinX said:

The first thing you did wrong is paint in this weather. Lost of moisture in the air. Then how many coats and how heavy? I believe VHT needs heat to cure once applied to engine parts to

Hey, thanks for the reply.

it was painted and dried indoors, so moisture should be a minimum- around 19 degrees I believe.

3 coats- a dusk coat and 2 further.  Not sure how to describe how heavy- I’d say sufficient with appropriate drying times between coats.

ultimately that is my question, it needs heat to cure and I wonder if anyone has any idea how to do this off the car?

Link to comment
Share on other sites

I wouldn't have thought VHT paint was required for a gearbox but some VHT paints need a primer and some don't. I never painted my diff fins because paint adhesion onto aluminum or alloy surfaces can be a bit flakey especially if the surface isn't super clean. As evin says you do need to cure these ceramic paint after they have gone touch dry. A curing oven for 30 minutes is usually recommended but if you don't have a oven large enough to accept the casing then a heat gun is going to be your only solution. 

With a heat gun you will struggle to get to the required temp over a long time across a large surface area so its not ideal. If you read around with this kind of paint they talk about sticking in ovens at 180C for the curing process. A heat gun runs a lot hotter than this at the tip so you can get there but it'll take a good amount of time to cure an entire casing worth of paint.

Edited by rider (see edit history)
Link to comment
Share on other sites

On 1/11/2021 at 8:18 AM, rider said:

I wouldn't have thought VHT paint was required for a gearbox but some VHT paints need a primer and some don't. I never painted my diff fins because paint adhesion onto aluminum or alloy surfaces can be a bit flakey especially if the surface isn't super clean. As evin says you do need to cure these ceramic paint after they have gone touch dry. A curing oven for 30 minutes is usually recommended but if you don't have a oven large enough to accept the casing then a heat gun is going to be your only solution. 

With a heat gun you will struggle to get to the required temp over a long time across a large surface area so its not ideal. If you read around with this kind of paint they talk about sticking in ovens at 180C for the curing process. A heat gun runs a lot hotter than this at the tip so you can get there but it'll take a good amount of time to cure an entire casing worth of paint.

Sorry, missed the update- thanks! It’s all off now, and hammerite on. 

Looked to be the wrong solution, so stripped it- it’s all a learning curve.. looks fab now, and the hammerite has adhered really well. 

Link to comment
Share on other sites

On 1/11/2021 at 5:34 PM, Swampy442 said:

Youre painting onto Aluminium, you need to etch prime it first to give the paint something to hold on to

Thanks @Swampy442- good advice, I did do a test patch to see if it would adhere at all. As you say, definitely needs primer. But now looks pretty bloomin amazing, and the paints dried well.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.