T2 Build-Series #13

Paint Time! :)

Previously:
KEP's T2 .21 Presentation
KEP's T2 .21 Freebie
KEP's T2 .21 Build Series #1
KEP's T2 .21 Build Series #2
KEP's T2 .21 Build Series #3
KEP's T2 .21 "Inspirational" Article
KEP's T2 .21 Build Series #4
KEP's T2 .21 Build Series #5
KEP's T2 .21 Build Series #6
KEP's T2 .21 Build Series #7
KEP's T2 .21 Build Series #8
KEP's T2 .21 Build Series #9
KEP's T2 .21 Build Series #10
KEP's T2 .21 Build Series #11
KEP's T2 .21 Build Series #12

Now it's time for paint and clear coat. This can be quite daunting and it needs a bit of an investment in equipment but if you like this hobby I think its worth it! :)

You can do this of course in several different ways but I can only describe how I do it. You need to decide what products to use and learn how to do it yourself. The products I use I can really recommend. So if you can get hold of them you at least have a very good base. :)

Stuff:

• A good air compressor with a tank. I use an super-silent professional Italian made airbrush compressor from Sil-Air (30/6) as I painted A L O T of RC car bodies back in the 90's. A good external airfilter and adjustable airflow/pressure of course.
• An airgun. I use an Italian made one from AsturoMec that is called ES. It has an 0.7 mm nozzle/needle and I paint everything from sanding primer to clear coat with it. But I would'nt recommend it for painting off-shore boats etc as the 0.7 mm nozzle is too small for that bigger coverage. But for riggers it's perfect size. Ive had mine for many years now (10-15) and it has never failed.
• Good masking tape.
• Sharp hobby knife.
• Tag Rags (sticky cloths that you use before paint to remove dust).
• Denatured alcohol to clean the parts before masking.
• Laquer thinner to clean the airgun with.

Paint:

• I mainly use the House of Kolor brand. That's a custom brand that have many different colors and base coats. I buy it HERE.
• House of Kolor #KS-10Q Ko-Seal II White Base Coat with KU150HP Catalyst & RU310 Thinner. That's used where any Neon color will be painted.
• House of Kolor #KS-12Q Ko-Seal II Silver Base Coat with KU150HP Catalyst & RU310 Thinner. That's used where candy will be painted.
• As we race our boats most of us use some sort of Neon. I have used Neon Orange, Neon Magenta on my riggers but this time I will paint my own boats in Neon Violette (purple) and a test pair of sponsons and matching cowl in Candy Tangerine. I will paint Sunken's boat Neon Orange and Mattias new 21 in Neon Pink. All by House of Kolor.

Clear Coat:

• I use a 2K clear coat from Sikkens that is called Autoclear Plus HS - I like that a lot.
   Everything except my ride-pads and ski's is covered with 3 coats of this clear coat.

Here the sponsons are mounted on their simple holders and masked. I maske off the bottom part of the sponson - the top part will get paint and the lower part will be clear coat only. Before that they are of course cleaned with denatured alcohol and dust removed with a tag-rag etc.

This set will get an first for me - silver basecoat and candy tangerine color! The sponsons are actually covered with 2 layers of silver (same as the cowl) but depending on the view angle it's not visible almost. It's transparent for sure and that could be an issue if you would have laid it on a primer based sanded surface though. The base needs an uniform color for sure. In this case the wood grain will actually slightly be seen through the paint but I think that is cool.

White base coat is laid on in 2 coats with flash time in between. All white parts will get some House of Kolor Neon on them.

Here are some of the pre-mixed batches of House of Kolor I will use this time. From left: Neon Orange, Neon Pink, Neon Magenta & Neon Violette. All of them are 1K paints that needs an white base coat and the reducer/thinner is RU310.

 2 coats of Neon Violette is what was needed - max 3 should be used. The two cowls to the right are the ones that got some sanding primer in the earlier article. The other tow cowls are molded with clear gelcoat and didn't need any sanding primer - just the white base coat. These are ready to be cleared.

The matching Neon Violette sponsons waiting to be masked-off (the lower part of the sponsons) & cleared.

2 layers of Neon Pink for Mattias Bengtssons T2-21.

I mixed up some 0.7L of Sikkens 2K clear coat and started to clear everything... Most parts got 3 coats but some was enough with two coats. You should not use more then 3 coats.

Neon Violette colored T2-21 sponsons cleared and done.

They look way cooler out in the sun but on a cloudy day they might not be that visible... ;) House of Kolor Kandy Tangerine.

Cleared and ready!

The tubs are also cleared with 2 or 3 layers of Sikkens Autoclear HS clear coat including the engine/tank bay.

The airgun is cleaned for the last time carefully and everything left over night to set. Minimum 24 hours.

 This is a mock-up of one of my own new T2-21's the day after - Neon Violette. Looks good in the sun. BUT you should not have newly painted Neon boats out in the sun that much the first few days!

And finally Mattias manly Neon Pink colored T2-21. :)

Next time I start the assembly!

T2 Build-Series #12

Sealing the wood with epoxy resin!

Previously:
KEP's T2 .21 Presentation
KEP's T2 .21 Freebie
KEP's T2 .21 Build Series #1
KEP's T2 .21 Build Series #2
KEP's T2 .21 Build Series #3
KEP's T2 .21 "Inspirational" Article
KEP's T2 .21 Build Series #4
KEP's T2 .21 Build Series #5
KEP's T2 .21 Build Series #6
KEP's T2 .21 Build Series #7
KEP's T2 .21 Build Series #8
KEP's T2 .21 Build Series #9
KEP's T2 .21 Build Series #10
KEP's T2 .21 Build Series #11

Now it's time to do the final preparations to start preparing for paint... What you should do first is sand everything the way you want it to be. Be careful and sand smooth and straight, pay attention to the corners etc. There are a few places where you should keep the edges on the "sharp" side. That is the ski and the separate running pads for the front sponsons. Sand the edges flat and sharp to begin with on these parts and then just slightly smooth out the edges... Just a tiny amount. In a perfect world you should/could keep them sharp but in reality its hard to get any paint to stick to a sharp corner so if you want to paint the parts that will be in contact with the water (ski & sponson running pads) make sure you put some radius on them but as little as possible...

Of that same reason - I personally don't paint these items. I only use epoxy on them - no paint - no clear coat. The epoxy I use is water tight though - so far we have had no issues with that and it's a bit easier to sand the edges sharp(er).

NOTE: the rear ski-ramp should NOT be glued to the tub permanently. It's meant to be mounted with thin double sided tape so you can change it or adjust the height etc. If you would glue it directly to the tub it will sit at the wrong depth and the boat will most likely run too light on the front sponsons in race waters.

Here are the batch of ski's and running pads that are sanded and ready for epoxy prep. These items will not be painted. Just epoxy. I have also made some extra running pads in different thicknesses: 2, 2.5 & 3mm thick. There are also a few different ski's in there that will be tested during the season. I'll get back when they are tested and if I have found anything that is an improvement. :)

This is the German chemical & water resistant laminating epoxy resin I use when prepping the wood parts. It's called Epoxy Resin C + Hardener C and its simply awesome. Protective gloves, house holf paper of a high quality that doesn't brake up when handled so to speak, a micro weight scale, mixing bowls and a bunch of good brushes that don't release any hairs.

Use masking tape on parts where you don't want any epoxy build-up.

Before "paint" you must seal all wood parts - we use the earlier C+C epoxy on all wood parts. The procedure I use is like this:

• Brush on mixed epoxy (note that C+C is mixed 100:60 (resin:hardener) everywhere on for example the tub first. Use a brush to spread it and move fast - you don't want it to "kick" before you are ready. In the radio room and the "bate box"- use your glove protected fingers to reach areas where a brush won't do the job (like under the deck parts). Also use a small rod to spread the epoxy resin into the holes - but don't fill the holes. When all parts are covered with the epoxy use your hands (with one or two layers of protective gloves) and massage all areas of the parts you just now have brushed on epoxy on...
• Then use the good household paper and start to remove as much as possible of the still not hardened epoxy...
• The idea of this first layer of epoxy is to get it INTO the wood. You don't want it to create any gloss surface so to speak. Remove as much as possible. BUT there is an exception and that is the bate box (the small area in front of the transom) and the radio room. These are so tight that you will not reach them to use any sand paper afterwards so you can leave a little bit more epoxy here but not too much. 
• When you're done with lets say the tub, move on and do the rest ot the parts in the same way and let it cure for at least 24 hours...

When the epoxy have cured it's time to sand everything again so it's a good idea to remove the masking tape etc before sanding starts. If you have left too much epoxy on the surfaces you will now notice that it's not easy to sand epoxy...

• Sand everything smooth again and blow off any dust.
• Re-do the masking tape.
• Start over again with layer #2 of the epoxy resin. This time it's a little bit different as it's easier to brush on the epoxy as the wood surface now is smoother. If you use the R&G C+C epoxy it's perfectly safe to only use 2 layers of epoxy before paint/clear so when you are repeating the process and are removing the excess epoxy with paper rags you can leave a slight glossy surface. But just a tiny bit...

• When all of your wood parts are done twice you should leave them for at least 48 hours before any final sanding. But the engine/tank compartment could use a third layer of epoxy and that you could do in between so to speak. If you are in doubt - leave all parts for a complete hardening for a week in room temperature before any final sanding will be done to start prepare for paint/clear. Remove the masking tape first though.

• When all parts are fully cured it's time to do the final sanding! Be careful on all edges so you don't sand through the epoxy down to the wood.
• I also re-drill all holes at this time to remove excessive epoxy build-up.

When the final sanding of the tub is done I glue the brass tube for the antenna tube in place.

In an earlier article I showed the magnet cowl hold downs - here I have mixed a batch of 10 minute epoxy with milled fiberglass and used that as putty over the protruding magnet. Then sanded it smooth to form a "bulb". Looks ok, I think.

If you have a cowl that has been molded without any gelcoat, it's a good chance that when sanding it will show up quite a lot of pores or pin-hoes in the epoxy surface... Up until these cowls I have actually not cared for a super finish on the cowls - I have seen the function of them only. But these where prepped (spray gun) with a 2K sanding primer that filled most of the pin-holes. After blocking it out most of the holes went away. If a perfect surface was needed then a second layer of the sanding primer would have been needed but it was good enough for these boats. :)

Next time it's paint and clear coat in: KEP's T2 .21 Build Series #13

T2 Build-Series #11

I'm back with a new build article - sorry for keeping you on hold. :)

Ive had a busy time at work with us (Minicars that is) attending the Nürnberg show with our own booth and also starting building a new T2-44 prototype. To add to the list that has happened during the article break I've also built some T2-21 stuff to friends in the UK... :)

It's now time for making the rear ski-ramp (version 1)!

Previously:
KEP's T2 .21 Presentation
KEP's T2 .21 Freebie
KEP's T2 .21 Build Series #1
KEP's T2 .21 Build Series #2
KEP's T2 .21 Build Series #3
KEP's T2 .21 "Inspirational" Article
KEP's T2 .21 Build Series #4
KEP's T2 .21 Build Series #5
KEP's T2 .21 Build Series #6
KEP's T2 .21 Build Series #7
KEP's T2 .21 Build Series #8
KEP's T2 .21 Build Series #9
KEP's T2 .21 Build Series #10


Here you can see two ski-sides that has roughly been cut out too big. The side material I have used is the same as for the tub sides. The white squares are thin double sided tape that is used to attach the two ski-sides together during the shaping process. That's the same procedure as when shaping a pair of tub sides...

Here the ski-sides are together and marked out. The flat parts have been sawed out in the band-saw and sanded flat, smooth and at 90 deg angle. When that is done you saw out the bottom part and carefully shape that.

Take the two ski halves apart and remove the left-over tape. The ski-deck and ski-bottom should be 1.5 and 1.0 mm plywood. It really doesn't matter if you use the 1.5 as a bottom or deck - if the other is 1.0 mm... The end result will be about the same.

Use a steel ruler as a glue guide for the first ski side to be glued. Tack it in the rear (on the oposite side as where you have the steel ruler) and make sure it's at 90 deg vs the deck (ZAP CA Green/medium). Move along forward and press the ski-side towards the steel ruler to keep it straight... When you have tacked it all the way to the front you can put a bead of ZAP along all sides. Leave it to soak in and use kicker after about a minute.

Draw a parallel line 30 mm from the outside of the glued ski-side as the ski width should be 30 mm... Start with aligning the rear ends so they are square and tack it at the rear with CA glue. Then you use the steel ruler again as a glue-straightness-guide again and make sure you follow the straight and parallel line.. When done put a bead of glue all the way around...

 Sand/trim the protruding plywood deck edges flush with the sides.

Ski bottom. Start at the rear where the bottom of the ski should be perfectly flat. Glue the ski assembly to the plywood bottom pressing down until the glue has set. Then put more glue on the utside joint for lets say 50 mm at a time and move forward pressing down until you have glued it all the way to the front. Saw it out and trim the protruding edges flush with the sides.

Also the rear edges is sanded flush and smooth.

 Sorry for blurry picture but this it what it shouldlook like now.

Mark the ski-deck with lines as to where it should be cut out for clearing the stuffing and flex brass tube. Use a cut-out disc in the Dremel and cut it out. Sand the edges smooth and double check on your T2 tub that you have clearence.

NOTE, the ski-ramp should NOT be glued to the tub!!! If you do that you are missing the point with the T2 design and you cant adjust or change it etc. Included in the design there is about 1 mm allowance for double sided tape and if glued directly to the tub it will sit (permanently) at a wrong (non adjustable) height. That will most likely make the boat run too light on the front sponsons.

Next: KEP's T2 .21 Build Series #12