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cuemaker
05-21-2006, 10:14 AM
2 questions in regards to painting a lathe.

1. Can a 2 part epoxy be wet sanded?

I am using this epoxy and a base coat and the data sheet says that another suitable top coat of epoxy, urethane or acrylic maybe used for color but not a alkyd-oil topcoat. ( got a half gallon free of PPG "pitt-guard" from the PPG rep)

2. Does this eliminate the industrial enamels?

PTSideshow
05-21-2006, 10:31 AM
don't see why you can wet sand or any kind of sand the epoxy, but as they say try on a small section or do a test coat piece before the main one.

As always follow the manufactures directions on the top coat or waxes. as the items in it or the top coat can and do react badly with each other. Causing a mess. nothing worse to clean up than a half a** dried or concegealed mess of epoxy.

thistle
05-21-2006, 10:32 AM
you should not have aproblem wet sanding the epoxy.I should also imagine that after a week or so the expoxy should be fairly inert and as long as you washed it well with water and soap to remove any possible amines from the surface you shuold be fine putting anything on it.

Frank Ford
05-21-2006, 11:18 AM
If you use kerosene as a lubricant, I think you'll not only find that it works better than water, but you'll also be able to use any kind of abrasive sheet, waterproof or not.

aboard_epsilon
05-21-2006, 01:42 PM
If you use kerosene as a lubricant, I think you'll not only find that it works better than water, but you'll also be able to use any kind of abrasive sheet, waterproof or not.

if you use that stuiff as lube , you will have a hell of a job cleaning the residues off and getting the paint to stick after.

all the best..mark

Frank Ford
05-21-2006, 05:03 PM
I must admit I don't do metal finishing, so my materials are a bit different, but for the last 40 years I've used kerosene or mineral spirits as my first choice for lubricating when block sanding finish to avoid any possibility of raising wood grain.

At least for my materials - primarily shellac and various kinds of lacquer, I've never had any problem with adhesion. Often my cleanup consists only of a quick wipe with a clean rag.

Could be that subsequent coats of epoxy or enamel aren't as friendly as my shellac, so cleanup might be an issue.

CCWKen
05-21-2006, 06:43 PM
1. Can a 2 part epoxy be wet sanded?

I am using this epoxy and a base coat and the data sheet says that another suitable top coat of epoxy, urethane or acrylic maybe used for color but not a alkyd-oil topcoat. ( got a half gallon free of PPG "pitt-guard" from the PPG rep)

2. Does this eliminate the industrial enamels?

Epoxy primers MUST be sanded if you don't topcoat within 4-6hrs (Usually--Check the data sheet). Most of the epoxy primers are meant to be top coated, without sanding, within a certain time period. These paints are not like epoxy glues/resins that form a wax-coat during curing. If you wait too long, the surface becomes too smooth for paints to stick to it. That's the only reason epoxy primers need to be sanded at all.

Wet (water) sanding is about the only way to sand the stuff without clogging the paper. If the surface finish is to your liking--no drips, runs or errors, then you can just scuff the surface with 3M Maroon pads or the like. DO NOT use any oil based products over epoxy primers, if you want the paint to stick. And, don't use oil products to sand the epoxy. It will be near impossible to get it out of the microscratches of sanding.

Commentary: I don't understand the logic behind folks spending thousands of dollars on a machine and tooling and hundreds of hours reconditioning a machine, supposedly to last another lifetime, and can't spend less than $50 on quality paint. But hey, I'm more of a painter than a machinist so the reasoning is beyond me. I guess if you're just throwing color on it to get rid of it then maybe that's the support you need. It seems the offshore mentality is firmly entrenched in our minds--Just get it done, quality and longevity is of no concern. :(

cuemaker
05-22-2006, 10:13 AM
Commentary: I don't understand the logic behind folks spending thousands of dollars on a machine and tooling and hundreds of hours reconditioning a machine, supposedly to last another lifetime, and can't spend less than $50 on quality paint. But hey, I'm more of a painter than a machinist so the reasoning is beyond me. I guess if you're just throwing color on it to get rid of it then maybe that's the support you need. It seems the offshore mentality is firmly entrenched in our minds--Just get it done, quality and longevity is of no concern. :([/QUOTE]


Ken,

I know your not trying to poke at me to hard and you have given me excellent advice in private messages also. Lemme explain my thought process that I have been going through.

To start I only took apart the lathe to move it. Then someone suggested that since I have it apart, I might as well paint it. I thought it a smart idea! Plus it was very dirty and once I get it moved I would be working with wood and not metal an having a clean lathe without grease or grim would be a good thing.

So I start doing searches on paint on this forum and PM. I have read alot. Lots of different opinions and such. The one prevailing thought of which you just expressed, pay decent money for excellent paint. While I agree and I am the type to spend a bit more on something I want to last, my budget disagreed. To make matters worse, the good stuff that I could/can find only comes in gallons or more. To make extra hard, I need 2 colors.

Take polan b. 2 parts, about $81 per part. so I would get 2 gallons when a half gallon would be more than sufficient for $160. Then I need another quart of a different color forth the stand. While I can use a less durable paint for the stand, it would be hassle it seems.

So I read that some people use the TSC enamel products. The reason I was considering it was for to reasons. 1. Price $8 dollars a quart and I can get it in quarts. 2. My demands on the paint will be very little. Might bang a half pound of hard rock maple in it. It should stand up. But with an excellent paint, IT WILL STAND UP! with out the worry having to repaint it.

Then that bug gets in me again, "if your gonna do it, do it right". You help reaffirm that bug in a email by telling me that I can do better than the TSC stuff. You also tell me that I can buy an automotive paint in quarts for not to expensive.

I then luck out and the local PPG guy has a 2part epoxy paint called Pitt Guard in his garage that he gives to me free. I get a quart of the paint and a quart of the catalyst. But its a very ugly gray (cement color), and its goes on very very ugly. I figure it will be a good primer coat. Plus it gets my bare metal covered now as opposed to sitting there rusting.

So now I am looking for color. My search is on for a local auto paint supplier. I have made a couple half hearted attempt with out much luck.(need a columbus phone book)

And when I find that supply store, I am emailing you Ken,again, to help me make a choice.

This is probably way more than anybody wanted to know.

claw
05-22-2006, 10:50 AM
Moores PBE
3211 W. Broad St.
614-272-2255

cuemaker
05-22-2006, 11:07 AM
Damn claw, thanks!

Reasonable too (it seems)

MTK Acrylic Urethane by PPG
quart of color 19.65
pint of hardener 12.35
Gallon of reducer 19.00 (only size)

Draw back, it dont brush on good, ment to be sprayed. :(

RPM
05-22-2006, 12:39 PM
While we're busy talking about 2-part epoxy, lets remember that its echnical name is isocynate, the cyn being cyanide! Although most of the dangerous stuff will have disappeared after curing, you must be careful of dust etc. Wet sanding will, of course, keep this dust confined.
I'm more concerned about using this to brush on your lathe, even the fumes of this will get you good, and a high grade filter is not enough to protect you. (Don't ask how I know). This must be done outdoors, or in a very well ventilated area. Do a google on isocynates for more facts.
Richard in Los Angeles

cuemaker
05-22-2006, 01:11 PM
While we're busy talking about 2-part epoxy, lets remember that its echnical name is isocynate, the cyn being cyanide! Although most of the dangerous stuff will have disappeared after curing, you must be careful of dust etc. Wet sanding will, of course, keep this dust confined.
I'm more concerned about using this to brush on your lathe, even the fumes of this will get you good, and a high grade filter is not enough to protect you. (Don't ask how I know). This must be done outdoors, or in a very well ventilated area. Do a google on isocynates for more facts.
Richard in Los Angeles

This one is called polyamide 2 part epoxy. But thanks for the heads up!

CCWKen
05-22-2006, 01:37 PM
No way Cue. I wasn't a poke directly at you. It was merely a general observation of the group as a lot. There's some fine work done on the ugliest machines but I'm not the one that has to look at the stuff. I really don't care one way or the other if anyone's machine is painted or not or that they used house paint. I'm simply giving an opinion of material that might work the best in the environment. The subject comes up often on this bbs and it ends up much the same way--Fine machinery covered with Rustoleum rattle cans.

I think I'm finally realizing what some of the master machinists here feel when someone talks about milling on a drill press or building their own surface grinder. It may work to complete the task but rarely with satisfactory results. Or... it might be that I'm just an old fart and know nothing of what I speak. ;)

My apologies if you took it personal. I guess I pulled a D. Cheney and you were the closest. :D Sorry.

cuemaker
05-22-2006, 02:04 PM
Ken, I didnt take it personally at all except that it directly applied to me. And you are right. I have taken this much time and effort to make it nice, why not a little bit more to finish it off right?

Now I need a compressor and air gun.

Ah the tools you have to buy to paint and make the tools you have work!

JCHannum
05-22-2006, 04:36 PM
It seems kind of ironic that the same guy that was grousing about the purchase price of the proper oils for a lathe is now advocating spending extra money for a sophisticated paint system.

A visit to any working machine shop will show the machines in their normal environment, and it is not always pretty. The work is dirty and hard on the finish of the machine. Paint wears away, is chipped or dissolved by solvents and coolants.

When you attend an auto show, you will see two very different classes of vehicle. The daily driver and the trailer queen. The daily driver is just that, a machine that is being used as it was intended. The trailer queens may be pretty, but they are coddled and will never go very far under their own power because the owner is reluctant to expose them to possible damage.

My machines are daily drivers. I cleaned and painted them with a brush or rattle can. They are clean, properly lubed and well looked after. I brush and vacuum them off after use and wipe them down with an oiled rag at the end of the day. If I ever get to the point that I feel the paint might need to be touched up, I can easily do it.

Until that time, I will enjoy and use them as designed. The quality of work that comes off them is not at all affected by the cost of the paint.

CCWKen
05-22-2006, 06:02 PM
LOL... :D

You're right Jim and I'm over that as well as painting other's equipment. I just kinda like a clean looking machine--Be it 100 years old or 100 hours. Hey, I'm not the only one here that likes that. ;)

I only mention the auto paint because it can stand up to the environment a lot longer. Touch ups are not a problem.

Fasttrack
05-22-2006, 06:15 PM
A little of topic but...Ken-

From my personal expierence i think the reason that rustoleum "rattle cans" are used so often is that finding and using the right kind of paint can be both time consuming and intimidating. Especially with all of the health issues associated with paint. I don't know if this applies to anyone else or not, but i know i'd take rustoleoum over alot of stuff because its easy to find, easy to use, hardly any "clean-up" and its not too hazardly like iso-cyanates are. I've just sort of worked up the courage to break into the world of automotive painting with this truck project of mine. Now that i'm looking into i'm getting more and more excited about learning how to paint/where to find paint/etc. I jus think it can be intimidating at first.

p.s. i may be needing your help in figuring all this painting and body work stuff out this summer - hope you'll be around to chime in on any threads!!

CCWKen
05-22-2006, 06:27 PM
You're right to be concerned about the health issue of auto paint but it shouldn't stop there and not all auto paints need or have isocyanates. I would suggest anyone painting anything review the MSDS sheet(s) for the product. You may be surprised at what's in that "rattle can".

Ah geez, don't get me started on body work. I'll have ya making patch panels at the hint of rust! ;)

God willing, I'll be around. :D