The bed spraying story

[DavidF]

Many have followed the questions I had from many months ago as I began the journey to "spraymanship" I had decided that enough was enough of the wipe on stuff and brushing finishes and time to get serious!!

After much investigation I ended up with this spray gun:

Amazon.com: Titan 4-Pc. HVLP Triple Setup Paint Spray Gun Kit, Model# 19220: Tools & Hardware

A good value gun I think. I have a 3 hp 10.3 cfm @ 90psi compressor to go with it. I bought a new 3/8th hose to give as much flow as possible. Spraying the bases which were roughly 4' square the compressor kicked in just once per side.

After much input from the guys here I decided to go with this finish system:

Target coatings Shellac sealer: Target Coatings - Products - Oxford UltraSeal-WB™

And Target coatings Lacquer: Target Coatings - Products - OXFORD ULTIMA SPRAY LACQUER

One coat of the sealer followed by 3 finish coats. The sealer was rubbed down with 400 paper before the next coats. I applied 2 more coats of the lacquer, rubbed down again with 400 and then applied the top coat. Spay interval was 1hr between coats unless I was sanding and for those I left 2 hrs. Both products sanded perfectly, sanding off a fine white dust without clogging the paper.

I was truly concerned about the gun setup so practised and practised and practised and practised...... until I was happy that I knew what all the adjustments on the gun were for! I started with spraying water and then moved to the lacquer (see later for **** up). I could not quite get the beautiful, even horizontal fan with equal dipping over the full length that I saw in some pics, but I could see the effects of the controls.

I found that above 30 psi at the gun inlet there was no real difference in atomization, the noise just got louder and the product bounced back more! The gun actually has the stamp "HVLP max 20psi) on the handle and I found that this means that to "comply" with regulations governing HVLP and to ensure that you do not have more than 10psi at the tip, then this is the max pressure. I actually ended up using 25 psi for all the spraying. The inlet restricter valve was fully open all the time.

For the base boxes I used the largest fan width which with this gun wasn't that big, say max 6" long. for this setting I used a material flow control of 2 turns out from fully closed. and this gave me a full wet coat.

For spraying the frames etc I tuned the fan down to about 50% full width and turned the material control in a half turn.

I sprayed the bases without the shellac sealer, they just had 3 coats of the lacquer.

When It came to the frames my first mistake was to assume that the shellac would spray the same - wrong!!!! it was worse than spraying water!!! it was dripping all over the place and going on way to much. Ok, I thought lets just try wiping it off, it can only mess it up completely and wreck 6 months work :lol: Much to my amazement I was able to wipe off the excess and clean it all up and when it was dry it was perfectly flat and all nice and smooth -an amazing product. Gun settings for this were the same inlet pressure but flow control was only one full turn out from closed, much better.

The lacquer coats went really well with one hr between coats. My other major screw up was forgetting to change from a horizontal fan I was using on the legs to a vertical fan for most of the spraying! there I was wondering why I had all this thick white mass of finish going on to the side rails! I was playing with flow, pressure etc, etc before I realized and then smacked myself in the head!! I had no choice but to leave it and get on with the other frames.

When the stuff had dried it was a real mess with runs all over the place. I took some 180G and sanded away all the runs, of course going through the original shellac as well!! Well I just got some of that shellac on cloth and rubbed it on and let it dry. As before it dried perfect:eusa_clap

I made a similar mistake on the last coat on one of the bases and was spraying with the wrong fan orientation (will I never learn?) and again ended up with a coat of finish about 1/16" thick!! well as before, nothing ventured etc.... So I got a slightly damp cloth and wiped it off!! It dried perfectly!!!!!! this stuff rocks...

End result was very, very nice straight off the gun although I will probably wire wool and wax the most "tactile" parts of the bed!!

The colour with the shellac base was a warm, almost pink shade on the cherry which I loved. I really don't go for the very red cherry that one see's on commercial furniture.

I was glad I went the spray route and will not be going back to the old ways very soon. It was much easier than I thought it was going to be and I am sure that is mainly because of the most forgiving nature of the Target coatings products - highly recommended. The Titan gun was $87 from amazon and I would also recommend this gun to anybody just starting out.

 

[MikeH]

Thanks for the insight David. It's always great to gain insight and knowledge from others experience. Do you have pics of the project? I'd like to see the finished product.

 

[Travis Porter]

Good to hear you survived Dave. I am getting ready to use the exact same finishes on my dresser so I know what not to do with the shellac now. The Target stuff is great stuff in my opinion. This will be my first time with the shellac, but I have no regrets with it whatsoever in the Lacquer.

 

[DavidF]

Good to hear you survived Dave. I am getting ready to use the exact same finishes on my dresser so I know what not to do with the shellac now. The Target stuff is great stuff in my opinion. This will be my first time with the shellac, but I have no regrets with it whatsoever in the Lacquer.

Hi Travis, If you haven't bought the shellac yet then I have a lot spare. I bought a gallon, but only used one spray gun full!! offer is there to anybody else also if you want a pint or two FOC please give me a shout.

I just ordered some of their Emtech 8000 series conversion varnish to re-finish our dining room table.

 

[DavidF]

Thanks for the insight David. It's always great to gain insight and knowledge from others experience. Do you have pics of the project? I'd like to see the finished product.

Right here: http://www.ncwoodworker.net/pp/showgallery.php?cat=772

 

[DavidF]

This was the respirator I purchased to wear during the spraying. Very comfortable and the quick latch is a great idea.

<br>QUICKLATCH™ PRO Dual Cartridge Respirator

 

[Travis Porter]

Thanks for the offer, but unfortunately, I have a gallon as well. Bought it at the same time as the Lacquer. When you say a "gun full", one quart cup? I am planning to spray the drawers and all with it so maybe I will use a bit more.

 

[dancam]

David,

Many thanks for sharing your experience with HVLP spraying. I bought a cheap HVLP gun from HF and will be giveing it a try in the near future, so your experince will come in handy.

I also really like the bed....great design and the integrated lights are super...good work.:eusa_clap :eusa_clap :eusa_clap :eusa_clap :eusa_clap

Dan C.

 

[DavidF]

Thanks for the offer, but unfortunately, I have a gallon as well. Bought it at the same time as the Lacquer. When you say a "gun full", one quart cup? I am planning to spray the drawers and all with it so maybe I will use a bit more.

Yep, One qt cup, that stuff goes a looonnngggg way:lol: :lol:

 

[DavidF]

David,

Many thanks for sharing your experience with HVLP spraying. I bought a cheap HVLP gun from HF and will be giveing it a try in the near future, so your experince will come in handy.

I also really like the bed....great design and the integrated lights are super...good work.:eusa_clap :eusa_clap :eusa_clap :eusa_clap :eusa_clap

Dan C.

Thanks Dan, I would like to see the difference in finish between a $300 gun and the guns at the Titan end. Certainly in my hands:lol: :lol:. I guess it would be more even atomization across a larger fan as I mentioned in the posting.

 

[DavidF]

One thing that was a pain was the stiffness of the 3/8th hose I had. Any body know of a super flexible hose that would be great for the final 10 ft or so before the gun?

Thanks.

 

[NZAPP1]

Thanks Dave for sharing your experience with both the spray equipment and the coating product :icon_thum I may have to buy that set up since it has worked so well for you

 

[Gofor]

David: Looks like you did very well with it and made some excellent recoveries from your "learning experiences"! :eusa_clap:eusa_clap As for the air hose, from your post it appears you are getting plenty of air to the gun based on your being able to cut the pressure down significantly from the maximum. With this in mind, a 1/4"id hose for the last 10' should supply sufficient air volume. It can be bought in very flexible formulas, and you could also use vinyl.
Keep in mind that the more flexible the hose, the easier it is to kink it and cut off your air supply. They sell the vinyl in self-coiling packages with fittings attached. Personally I have found these to be a real pain with the loops getting caught or tangled around anything remotely in reach, as well as prone to kinking. They do work very well if you suspend your hose overhead so the vinyl hose drops from the ceiling. This has the added advantage of removing the hose from being a tripping hazard. If you go with a rubber-type hose, you may have to buy it by the foot and install your own fittings. You should be able to get it at an auto-supply outlet or agri-supply, etc. Anything with a burst pressure of double the maximum of your air supply will work.
As for the shellac going on too heavy at first: The thinner the coating (i,e the faster it runs off the stir stick) the less you want coming out (the fluid adjustment closed more for the thinner coating). I noticed from the Target water-based lacquer spec sheet that it has a viscosity of about 40 seconds with a #2 Zahn cup. That's fairly thick as far as spray finshes are concerned. I imagine the shellac would be closer to 15 secs, so closing the fluid adjustment was exactly correct.
Thanks for sharing your experiences and your review of the spray system. There is a lot of good info there for both novices, and the more experienced that have not sprayed the water-borne finishes yet.

Go

 

[NCPete]

yeah, I have the vinyl self coiling hose for the last 20 feet of my hose now, and it does catch everything, including my feet, but the tool in hand is soooo much lighter

 

[stoneskippers]

Great job on the bed. I really like your design.

 

[cpowell]

Thanks for sharing your experience David.

I need to take the spray gun plunge myself. I bought a PC PSH1 gun and am glad it's not made of iron...it'd rust before I use it!!! I have sprayed with general purpose gun but nothing more than fence painting.

Chuck

 

[DavidF]

David: Looks like you did very well with it and made some excellent recoveries from your "learning experiences"! :eusa_clap:eusa_clap As for the air hose, from your post it appears you are getting plenty of air to the gun based on your being able to cut the pressure down significantly from the maximum. With this in mind, a 1/4"id hose for the last 10' should supply sufficient air volume. It can be bought in very flexible formulas, and you could also use vinyl.
Keep in mind that the more flexible the hose, the easier it is to kink it and cut off your air supply. They sell the vinyl in self-coiling packages with fittings attached. Personally I have found these to be a real pain with the loops getting caught or tangled around anything remotely in reach, as well as prone to kinking. They do work very well if you suspend your hose overhead so the vinyl hose drops from the ceiling. This has the added advantage of removing the hose from being a tripping hazard. If you go with a rubber-type hose, you may have to buy it by the foot and install your own fittings. You should be able to get it at an auto-supply outlet or agri-supply, etc. Anything with a burst pressure of double the maximum of your air supply will work.
As for the shellac going on too heavy at first: The thinner the coating (i,e the faster it runs off the stir stick) the less you want coming out (the fluid adjustment closed more for the thinner coating). I noticed from the Target water-based lacquer spec sheet that it has a viscosity of about 40 seconds with a #2 Zahn cup. That's fairly thick as far as spray finshes are concerned. I imagine the shellac would be closer to 15 secs, so closing the fluid adjustment was exactly correct.
Thanks for sharing your experiences and your review of the spray system. There is a lot of good info there for both novices, and the more experienced that have not sprayed the water-borne finishes yet.

Go

Thanks for the info on the hose. Yes, I am sure a self coiling hose would be a pain. I will try and short length of 1/4" next time I spray.

I just checked and the shellac sealer is 17 secs for a #2 cup so you were right on the money. Would it be a good idea to get a "Wet film thickness gauge" for controlling the coat thickness or is that going a bit too far for us amateurs?

 

[Gofor]

Would it be a good idea to get a "Wet film thickness gauge" for controlling the coat thickness or is that going a bit too far for us amateurs?

The short answer: Not a good idea. It wouldn't be very effective for wood.
Wet film thickness guages, both the step type and the roller type, can be of use on a non-porous surface (metal) but would probably be useless on wood, due the varying amounts of absorbtion. Not often used except where an in-progress quality control oversight is necessary. They are not an effective measurement, regardless, because it only gives you the thickness at the exact spot checked, and as you now know from having sprayed, the coating thickness will vary, especially on inside surfaces where you get some blowback from adjacent perpendicular pieces. If the guage is used after the coating begins to set up, it will leave a blemish in the finish which can be very difficult to correct. Your eye and experience are the best guage, as they will tell you that the coverage and flow-out is what you are wanting.
I have thought of getting one to check glue thicknesses to try to calculate the amount to achieve the optimal squeeze-out (I'm still trying to achieve that "enough but not too much" level, but have a long way to go, I fear). Again, I think experience will be the only really accurate measure.
If you want to get an idea of how thick your coatings are, you can make some "coupons". They will let you know how thick the coating is after it has dried. A coupon is basically a piece of metal with one bare strip and adjacent strips of tape equal to the one more than the number of coats you intend to spray. Lay it next to the object being sprayed and make a pass over it with the gun just like your are spraying on the object. After each coat, peal off one strip of tape. After it dries, you can measure each successive buildup of coats to see what thickness you had with the sealer, primer (if used) and following coats. The strip that started bare will be the total thickness as it will have all coats, the next will be minus the first coat, the second minus the first and second coats, etc. The last strip that did not get removed is your refernce measurement. If you also make one out of the wood being sprayed, it will give you a record of how it looked after each coat, as well as tell you how much each coat was being absorbed by comparing the measurement to the non-porous sample. Due to the variations in thickness after sanding it, etc, you would need to measure it at each width of tape and write the thickness on the back side for the reference. It would be a good reference sample if you were looking for a particular amount of shade variation, etc
Lots of ways to "measure" coatings if you really want to get scientific about it. However Murphy will jump in with temp and humidity changes so it will always be as much art as science.

I Know, Way too much info

Go

PS, if you really want a wet film guage, i can tell you how to make your own "step" type. If you ever look closely at one, you will see it is really a very simple tool that can be made from piece of sheet metal with a small taper file and a set of feeler guages.

 

[DavidF]

You can never have too much information!! Thanks for that. I just go by the "seat of the pants"