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Colchester Student Mk1 Won't Start

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Richard Kirkman 117/06/2020 17:26:09
300 forum posts
740 photos

I've not been very busy the last few days with the lathe. I've been working on the mower and a really fancy bowl

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Anyway, I decided to strip another piece of the lathe today

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I will take off the machine tag at some point

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And I flattened the primer on the headstock cover, so it'll get another coat of primer when I get around to it. I need to start spraying the primer so it goes on more evenly

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I'm struggling with stripping the paint from parts. The stripper leaves a very stubborn gooey mess behind which is tricky to remove. Are there any tips or tricks to help it go a bit better? Or a better type of stripper?

Herman van der Merwe17/06/2020 20:00:12
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174 forum posts
Posted by Richard Kirkman 1 on 17/06/2020 17:26:09:

I'm struggling with stripping the paint from parts. The stripper leaves a very stubborn gooey mess behind which is tricky to remove. Are there any tips or tricks to help it go a bit better? Or a better type of stripper?

I used normal brake fluid. Brush it on and leave for at least 12h. Then the layers paint and grey putty filler goes soft and you can brush this off with a stiff dome wire brush. Some areas we resorted to using a heat gun and a flat scraper sharpened every 15 minutes to a dead flat end. Stripping takes forever and ever. Two weeks of constant cleaning and donating quite a bit of blood to get the stand clean ....

Richard Kirkman 119/06/2020 21:06:47
300 forum posts
740 photos

Slow progress. I've been busy with the mower and other things. The cover is all stripped now, it was a nightmare. I'm getting a bit of a method going to get it clear quickly.

I've decided I'm going to paint the inside of this, and the gears that are covered by it, red. While keeping the outside grey. It will hardly ever be seen, but I want some red on it somewhere!

More mower work to be done. I'll probably strip the tailstock next as that'll be a nice section to do.

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The wheels in the background are the 4 wheels that make up the mowers seats roller, took ages to clean all 4 of them and to get them ready to paint, now they're the nice ransomes green.

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Looking forward to this week's video Phil!

Edited By Richard Kirkman 1 on 19/06/2020 21:09:19

Herman van der Merwe20/06/2020 07:37:46
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174 forum posts

I would seriously recommend you first apply a coat of zinc chromate primer onto the steel before using any body filler or putty. Otherwise the steel will oxidize under the putty/filler and lift it and create an area of loose top coat.

Richard Kirkman 120/06/2020 12:23:48
300 forum posts
740 photos

Quick update

Seal arrived for the forward reverse shaft, So I've fitted that with the silicon RTV sealer too. Hopefully it won't leak

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Then I finished cleaning the aluminium completely, then i finished smoothing the filler and lumps in the casting, then did a coat of primer on the inside.

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There are a few loose parts on the lathe that are tempting me to strip them, but i must concentrate on the lawnmower!

Phil Whitley20/06/2020 15:02:07
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1250 forum posts
147 photos

Hi all, Richard, you need to put an etch primer on the aluminium or the paint won't stay on, it is a difficult metal to paint, the yellow dust coat in my pics of my lathe rebuild are the etch primer. Once I had removed all the repainting on my lathe with thinners (acetone) I flatted the original paint finish, and feathered out the edges with a sander where the original paint was missing, I then etch primed all the bare metal, and used high build acrylic primer till the repairs dissapeared, then denibbed it and put the finish coats on. Stripping the lathe back to bare metal will be torture, and if the paint stripper gets to the original filler and starts to soften it, that will all have to come off as well. Much better to remove all the repainting, then rub down and prime the bare metal, and use cellulose stopper or fine surface filler on any noticable defects, then repaint. Nice Bowl!

Phil

Edited By Phil Whitley on 20/06/2020 15:03:42

Richard Kirkman 120/06/2020 18:51:45
300 forum posts
740 photos

Where would I be without your help!

Any idea what the easiest way to strip what I've done is? Same as normal paint even though its just primer? Or will I be able to dissolve it with some thinners or something? I'll go try putting some different things on it

I'll get some tractol etch primer at some point. Maybe Monday.

I won't strip the whole cabinet since most of the paint is fine on that, but it's badly damaged on the bed, headstock, and gearbox, so I may as well strip completely. Plus, my brother has just finished his degree and will be moving home this Friday with nothing to do, so I may have a personal stripperlaugh

I bought a Moore and wright protractor since I've never had anything to measure angles in the garage before. Anyway, the box it's in is pretty crappy, so it looks like I'll have to put my woodworking to good use and make myself a box!

Herman van der Merwe20/06/2020 20:06:35
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174 forum posts

Hi @Richard, as I said, the only thing that worked to soften the paint and putty was brake fluid. As @Phil said once you start you need to get to bare metal otherwise the old filler and paint will react with the cleaning stuff you use and most likely with the new paint you paint over with. Then you need to apply a zinc or strontium etching primer to lock everything up tightly against oxidation. Only then can you apply a filler primer.

I am resorting to sand blasting on the bed as you simply cannot reach into the bed cavities. The sand must be very very fine so as to not damage the old steel.

If I could choose, I would do all my paintwork in 2K. It is a bit more expensive, but then you have a lasting paint job.

Richard Kirkman 120/06/2020 20:29:40
300 forum posts
740 photos

The red oxide primer that I put on this morning came off quite easily with just white spirits and a good old rub.

I hadn't thought about the bed cavities. Another excuse to buy a compressor perhaps

The paint stripper I have been using has softened the paint and putty well enough so far

As a hobbyist, I think tractol will be tough enough for me, especially if it hardens properly. I don't plan on getting rid of the lathe any time soon.

Correct me If I'm wrong, but my takeaway is, for aluminium I need to use an etch primer then normal paint. And on all parts that I put the paint stripper on, I must remove all of the paint back to bare metal as to not leave any soft. Also, I must prime, whether etch or normal before I use the filler.

Phil Whitley20/06/2020 20:48:54
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1250 forum posts
147 photos

Once you get back to the original paint, leave it! feather the edges of any bare metal areas with a sander to thin the paint edge and make sure the paint is sound, then etch prime the bare metal. if you can still see the bare metal area, use a very thin layer of cellulose stopper or heavy coats of sprayed primer till there are no visible repairs, then denib it and put on the finish coats. Denibbing means sanding dry with fine abrasive 120 to 200 till the primer feels smooth. When using an oil based paint, you do not need the perfect primer coat that you need with cellulose paints, but you need a spraygun to speed up the whole process. Remember, remove all the overpainting, but leave any good areas of original finish or filler alone. You have seen the finish on my lathe, that is exactly how I did it! Stripping it back to bare metal is a nightmare, the castings are a lot rougher than they look, they used to cover the whole casting in stopper (cellulose putty) and then wet flat them and primer. Even in a heated paint shop, leave the stopper 24 hours for even a thin coat before you try to wet flat it. Fine surface filler to which you add hardener is better, but you have to put it on thicker than stopper, and it is tricky to rub down without breaking through, because it takes a lot more rubbing to get a good finish. several coats of sprayed on high build acrylic primer can save many hours of frustrating fill wait flat repeat cycles!

Phil

Phil Whitley20/06/2020 21:12:25
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1250 forum posts
147 photos

Richard, just read your new post, I have always stoppered or filled onto bare metal. You absolutley have to use etch primer on aluminium, it is optional on steel, but a good idea on cast iron, which has free graphite on the surface, wipe down the bare casting with a thinners damped rag and see the black come off! The etch primer is applied as a dust coat, one coat only, and you should be able to see through it, get spec sheet with the product you get for instructions, it should just tint the substrate, not blank it out completely. Any paint and filler which has been softened by the stripper will have to be removed, which is why I dont use stripper on machinery. Tractol is a very good product, and give excellent results when sprayed or brushed, I have used loads of it. but the finish comes from the preperation and the smoothness of the primer coats, the better they are , the better the finish! There is a knack to using and flatting stopper (cellulose putty), it is like thick primer that you apply with a knife or plastic card. Applied thinly to the bare casting (as they did at the factory) then wet flatted 24 hours later, can bring the areas of bare metal up to absolutely level with the existing flatted paintwork, and then a couple of thin primers are all that is needed. Have a look for some online tutorials on machinery refinishing/painting.

Phil

Edited By Phil Whitley on 20/06/2020 21:17:19

Richard Kirkman 121/06/2020 20:43:23
300 forum posts
740 photos

Thanks Phil, that's very informative.

I've been working on the lawnmower today. I've finally got some of the chains off, so it's coming to pieces so I can make some progress.

Looking at the Tractol data sheet for their etch primer, it says I need

1 x TRACTOL 729 (Etch primer)

1 x TRACTOL 816 (Red oxide primer)

1 – 2 x TRACTOL 329(Machinery enamel)

So this means the etch primer still needs coating with normal primer too?

Are there any more aluminium parts on the lathe that I need to worry about?

I have aluminium parts on the lawnmower too, so I'll be able to spray a few things at once.

Herman van der Merwe22/06/2020 08:47:28
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174 forum posts
Posted by Richard Kirkman 1 on 21/06/2020 20:43:23:

1 x TRACTOL 729 (Etch primer)

1 x TRACTOL 816 (Red oxide primer)

1 – 2 x TRACTOL 329(Machinery enamel)

So this means the etch primer still needs coating with normal primer too?

Are there any more aluminium parts on the lathe that I need to worry about?

If that is what they say that is what you need to do.

Having said that you need to remember that you need to level the surface you will require a fille primer coat and body filer and spot filler as Phil said. This filler coat should be light grey as you can see the dings much better. Especially when you have spray a misting coat of black and you have sanded it a bit.

You can choose whichever paint you want, but I would seriously recommend that you use a painting system (in the above you looked at Tractol), but choose something with a filler primer in the system such as a 2K system. As per my thread I have once again learned the hard way not to mix paint types even though the separate paints were quality they did affect each other to the detriment of my mental health ...

Herman van der Merwe22/06/2020 08:48:10
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174 forum posts

As far as I see, only the drive end cover is aluminium.

The rest is cast steel or steel.

Phil Whitley22/06/2020 09:41:46
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1250 forum posts
147 photos

Hi Richard, yes! because the etch primer goes on in a thin dust coat, it tends to be uneven and knobbly, and you must not rub it down, so you bury it in primer, and flat it when dry. Like Herman, I use a 2k acrylic primer filler to which you add a hardener, it is high build (the highest I have ever used in fact) and it blanks out repairs quickly and dry sands well. If you are brushing the tractol primer, stir it well, as it seperates and all the filler part of the primer will be in the bottom of the can, then brush many thin coats, allowing the recomended drying time between each. fill in the repairs with primer first untill you have got the repaired areas back up to the original paint level, then flat off and give the whole job a couple of coats, let it dry thoroughly! Then wet flat and top coat. If you dont prime the whole machine, the repairs will show through because they will be darker than the original paint. The advantage with spraying is that you can put 4 or 5 coats of primer on in a day, then flat next day because the hardner in the paint ensures full overnight curing. Check with your tractol supplier to see if they carry "accelerator" to make their paint dry faster.

Phil

Phil Whitley22/06/2020 10:50:15
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1250 forum posts
147 photos

No more alumilium as far as I am aware, just cast iron and steel, use good quality paint brushes especially for the finishing coats.

Phil

Richard Kirkman 122/06/2020 11:35:40
300 forum posts
740 photos

Herman, I know 2k might be better, but I already have tractol. I'll need to redo the brass lathe tags/plates like yours too. The work you did on the holes in yours was amazing.

So where can I use the p38 body filler?

Or do I need to get a different filler

When you say your using primer to fill, is primer meant to fill? Or should I be trying to fill all cavities with body filler then smooth then prime?

I'm beginning to wrap my head around this. Seems less daunting than it did initially

The plan was to brush on a few coats of the red oxide primer to fill it a bit, then sand it down. Then I was going to spray a final coat of primer so the surface was even. Then I was going to spray the topcoats of the enamel.

This would allow me to work on lots of the lawnmower parts at the same time as I've been brushing the primer onto those as I've been stripping them too. I'm not a fan of cleaning out my sprayer so i want to do lots at once.

Herman van der Merwe22/06/2020 13:58:53
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174 forum posts
Posted by Richard Kirkman 1 on 22/06/2020 11:35:40:

Herman, I know 2k might be better, but I already have tractol. I'll need to redo the brass lathe tags/plates like yours too. The work you did on the holes in yours was amazing.

So where can I use the p38 body filler?

Or do I need to get a different filler

When you say your using primer to fill, is primer meant to fill? Or should I be trying to fill all cavities with body filler then smooth then prime?

I'm beginning to wrap my head around this. Seems less daunting than it did initially

The plan was to brush on a few coats of the red oxide primer to fill it a bit, then sand it down. Then I was going to spray a final coat of primer so the surface was even. Then I was going to spray the topcoats of the enamel.

This would allow me to work on lots of the lawnmower parts at the same time as I've been brushing the primer onto those as I've been stripping them too. I'm not a fan of cleaning out my sprayer so i want to do lots at once.

The way I am doing it at the moment is as follows.

I cleaned the surfaces to bare metal. I removed EVERYTHING. There are many casting holes and scares and uneven areas that needs to be leveled.

I wash the area with Parco cleaner and let it dry.

I then wipe the area with a lint free cloth.

Then one layer of two pack yellow Strontium etch primer.

Once this is set, I level the metal surface to be filled and spray one level of 2K filler primer. Once this is dried, I then use a self leveling body filler with activator and apply this to all the dings and holes I can see. The 2K primer is a light grey, so when you look against a light it allows you to see all the areas to be filled. When this has leveled off and set, I give the area a mist spray with black rattle can.

Once the mist coat has dried, I start sanding. Areas where low spots are, will remain full of black speckles. I keep on sanding until I see the yellow etch primer start showing and stop. Then depending on the area of black speckles and depth of the depression, I fill again with the self leveling body filler or just give another layer of 2K filler primer.

So I repeat the process until no black speckles show once the area is sanded. Each time I need to turn the stand and get it level before using the filler primer and self leveling body filler, so it is a long process.

Then it is time for the top coat.

Hope this helps in your approach with the Tractol painting system.

Richard Kirkman 122/06/2020 15:12:38
300 forum posts
740 photos

Thank you Herman that does help a bit. I have a good idea of what I need to do now. I'll run it through before I start to paint properly.

I stripped the threading gearbox lid today. My one is broken, but I don't plan on replacing it. Unless I find someone breaking the exact same model at some point in the future, since these lids vary in shape.

Removing the oilers was quite easy. I have some that are broken, not on this part. Is there a place to buy the oilers with the red aluminium discs too? Or should I just remove all the discs, they're looking quite tatty and worn.

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Also, capacitors finally arrived. I had to get them to send me some more since the originals were lost!

However, one is cracked. Will this be an issue?

Also, the numbers are slightly, instead of the 25/85/21 on the front, it says 25/70/21. From my understanding this means they are only rated to max of 70 degrees. Will this be an issue? Or should I send them back for being mislabeled?

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Herman van der Merwe22/06/2020 15:29:33
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174 forum posts

Posted by Richard Kirkman 1 on 22/06/2020 15:12:38:

I stripped the threading gearbox lid today. My one is broken, but I don't plan on replacing it. Unless I find someone breaking the exact same model at some point in the future, since these lids vary in shape.

Removing the oilers was quite easy. I have some that are broken, not on this part. Is there a place to buy the oilers with the red aluminium discs too? Or should I just remove all the discs, they're looking quite tatty and worn.

You can buy these at any machine part supplier. I can even obtain it over here in SA! You can make your own as well.

What is wrong with your lid? The square gap? Just braze a piece of cast iron in there and paint it over.

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