Painting vs Reverse Painting

[wfsteadman]

As it pertains to turning pens, what is the difference between painting and reverse painting?

 

[edstreet]

One goes on the brass tube the other goes into the drill hole on the blank. Both are weak structural.

 

[jttheclockman]

Reverse painting is the more productive and useful tool. Many times it is a necessity. If you do both the adhesion factor comes into play because of the layers you are putting between the parts being glued in. Plus build up of paint can mean the hole must be adjusted to accommodate the thickness. So painting the inside of tubes is the preferred method by many here. I would also suggest before painting to take some sandpaper and roll it up and sand the inside of the blank to get rid of the drill marks. Good luck.

 

[SteveG]

edstreet is correct on the loss of structural integrity that is introduced by painting. Since there seems to be little in the way of alternatives, except for color plated tubes, try to give painting the hole the best shot of working. Let the paint dry and cure completely before glueing in the tube. I have also used a brass "antiquing" solution to darken the brass tube. That process leaves a film on the tube which needs to be mostly removed, while still leaving some darkening color on the brass. For that I use a heavy handed wiping with a coarse cloth after the tube has dried completely for a while, post-aging solution. Both plating and aging solution approaches are providing color to the tube, rather than the preferred method of coloring the interior of the hole in the blank, so on the more translucent blanks, you will see undesired evidence of the glue, etc.

 

[qquake]

I've never had a pen fail "structurally" due to painting the tube and/or reverse painting the blank. I can see your point, by painting you're now relying on the adhesion of the paint for the strength in holding the tube in place. But I can't picture how it can be much, if any, of an issue. *Maybe* during trimming the tube could be dislodged. But during turning, the blank and tube are "sandwiched" together between the bushings. If trimmed properly, the bushings will apply pressure to both the tube and blank simultaneously. During assembly, you apply pressure on the tube with the part being pressed in, but the other end of the body should be on a flat surface preventing the tube from being dislodged. And when pressing in the part on the other end, you're now putting pressure on the tube and the first pen part together.

Have any of you had a pen fail in this matter? If so, I'd like details, and photos if possible, please.

 

[SteveG]

I think back over the years I have had some failures of a portion of the blank chipping off that could be primarily the result of a poor glue bond between blank and tube (both non-painted and painted). Could be I was overly aggressive. No pics available, but I recall inspecting to verify cause. I carefully pried the remaining blank from the tube. This is what I discovered: the glue (epoxy) remained adhered to the paint, but the paint came off the tube and came off the blank material. The weakest bond was the paint-to-tube, and paint-to-blank.

Possible causes: (random order)
1. Just that the paint is unsuitable, weak
2. #1 again, aggravated by not allowing paint to cure prior to glue-up
3. Poor surface prep prior to painting
4. Possible incompatible materials, i.e. the paint and the epoxy
5. Poor glue-up job, leaving voids

Based on my experience, I go gentle turning painted hole blanks, and have avoided subsequent failures attributable to painted hole situations. If turning a delicate blank, such as an intricate segmented piece, where I have painted the hole, I go extra careful, easy and slow to prevent causing a blowout.

 

[jttheclockman]

I can mention 100 things that are structurally affected when something is added. As mentioned a blank will break no matter if it is painted or not if proper tool use and technique is not followed. After the pen is complete no need for structural support. You have no choice when it comes to acrylics that are translucent. If you do not want to take that chance stay far away from those blanks and never do anything to the tube. Complete painting of inside the blank is your sure fire way to not see the tube when turned. When you start adding paint to the glue or painting of the tube you added other obstacles that can cause problems. Will they who knows for sure.

So to answer the OP the difference is in where you put the paint.

 

[campzeke]

I'm with Jim (qquake) above. I paint both and have not had any problems. What has not been mentioned here is what type of paint and what type of adhesive. I use acrylic craft paints and Devcon 5 minute epoxy. I paint one day and glue the next. I give the epoxy at least 4 hours to cure but in most cases let it sit overnight. I turn using a 15mm round carbide tool. Most of the time I am not an aggressive turner. I do not trim the corners off of the blanks but do take it easy until the blank is round. For me, it is not a race and I usually don't rush it. Works for me ....

 

[tomtedesco]

Reverse painting is the more productive and useful tool. Many times it is a necessity. If you do both the adhesion factor comes into play because of the layers you are putting between the parts being glued in. Plus build up of paint can mean the hole must be adjusted to accommodate the thickness. So painting the inside of tubes is the preferred method by many here. I would also suggest before painting to take some sandpaper and roll it up and sand the inside of the blank to get rid of the drill marks. Good luck.

I don't understand painting inside the tubes?? Do you mean inside the blank?

 

[campzeke]

Reverse painting is the more productive and useful tool. Many times it is a necessity. If you do both the adhesion factor comes into play because of the layers you are putting between the parts being glued in. Plus build up of paint can mean the hole must be adjusted to accommodate the thickness. So painting the inside of tubes is the preferred method by many here. I would also suggest before painting to take some sandpaper and roll it up and sand the inside of the blank to get rid of the drill marks. Good luck.

I don't understand painting inside the tubes?? Do you mean inside the blank?

YES!

 

[Edgar]

I'm with Jim (qquake) also - I always paint both tube & blank and have never had a failure during turning or assembly.

I use Krylon acrylic spray paint & med CA glue. I always let the paint cure at least 2-3 days, usually more. I then test fit the tube in the blank to assure a proper fit - if too tight I hand-turn a drill bit to remove the excess paint build-up. As I've gotten more experience and more consistency in my technique, that's rarely necessary anymore, but Inalways test the fit to be sure.

After finally gluing in the tube, I give it at least 24 hours (usually more) before turning.

I've recently started rounding off the corners of my acrylic blanks on a disc sander - not out of concern for structural failures, but it helps me to reduce chip-outs while turning the blanks round. I also use a disc sander with a squaring jig to square off the ends of the blank.

I have no argument that painting tubes and/or blanks reduces structural integrity, but with good techniques, I just don't see it as a big deal.

 

[jttheclockman]

Reverse painting is the more productive and useful tool. Many times it is a necessity. If you do both the adhesion factor comes into play because of the layers you are putting between the parts being glued in. Plus build up of paint can mean the hole must be adjusted to accommodate the thickness. So painting the inside of tubes is the preferred method by many here. I would also suggest before painting to take some sandpaper and roll it up and sand the inside of the blank to get rid of the drill marks. Good luck.

I don't understand painting inside the tubes?? Do you mean inside the blank?

Yes that is my mistake. No need to paint inside the tube unless you are using transparent tubes

 

[TonyL]

As it pertains to turning pens, what is the difference between painting and reverse painting?

I am prepping a bunch of pens for a client and she likes to see the steps.

The inside of the two blanks/barrels from the left have been painted. Yes, it is the inside of the turning stock that is reverse painted. I do not know the etymology of why it is called "reverse painting" - perhaps because the interior is being painted versus the exterior.

I like reverse painting because is hides not only the tubes (the brass, white, nickel things that comes with a kit), but it also hides the glues lines. Some know how to glue the tubes insides the barrels without the glues lines showing; I do not (nor what to learn).

I like using primer in all colors depending on the blank or effect.

I am a CPA, not an engineer, so I cannot comment on how these processes affect the structural integrity of the finished product. I would think the fewer the "materials" in between two glued services, the better - but I have know anecdotal, nor scientific proof.

I paint both the exterior of the tubes and the interior of the barrels and use epoxy. To date, and after close to 1,000 pens, I, nor any of my customers have reported any failures...that doesn't mean there are none or that the joints/contacts points are not weakening.

The barrels to the right have been reversed painted and the tubes have been glued inside. The other photo shows the barrels trimmed (made flush with the tubes), but still need to be cleaned out.

I hope this helps, and I hope I did not discount anyone's process or experience. I can only report my own.

Enjoy!

BTW, thank you for serving our country and protecting my freedom.

 

[qquake]

Hey Tony, I'm curious. Do you reverse paint wood and stabilized wood blanks?

 

[BSea]

As it pertains to turning pens, what is the difference between painting and reverse painting?

I like reverse painting because is hides not only the tubes (the brass, white, nickel things that comes with a kit), but it also hides the glues lines.

I agree with this 100%

I like using primer in all colors depending on the blank or effect.

When you say primer, are you just talking about the paint? Or do you use primer also to make sure there is no chance of brass showing?

 

[TonyL]

My first choice is only primer, but colors are limited (white, gray, rust, black) at HD etc.
I use the primer on both the inside of the barrels and the tubes.

I do not like the mixed, paint and primer combo, in the same can...too thick for my purposes. I have had success with automotive paint from AutoBarn.

However, my personal first choice is primer by itself.

I bought (and gave away) all of my craft paints... I didn't like they way they went on. But, many use them and make very beautiful pens using them to RP and paint the tubes.

And yes, no chance of brass showing. I don't like hiding anything behind clips, I don't feel that the exposed brass complements the barrel. But, others do.

 

[SteveG]

I have made my 2 previous posts on this thread, and after reading all posts, I wanted to add an additional comment, based on my experiences: I have not had ANY pens come back due to failed tube to blank adhesive probs with paint as a factor. The few failures happened during turning, no doubt the point of highest stress on that glue/paint joint during the life of the pen. The main point I was making is that I was able to ID the point of failure, and that was the at the interface of paint to the painted surface. So that was seen as the weakest point. The value of that fact to me is that I now do what I can to make that interface stronger than I did before, and I treat that interface much more gently, and as a result have had NO subsequent failures of that type. I hope that info is of value to other pen turners, which is my purpose in responding to this thread. (this may be of the most value to those who, like myself, tend to push the limits of 'getting it done', and as a result had to start over, something directly counter to 'getting it done'.

 

[zebramz]

Mark Z

I have struggled with the tube coloring process and epoxy glue up and am looking for additional advice.
First of all, I am new to pen turning (18 months). However, I'm a gentle Turner and meticulous. Some of my failures with coloring tubes/blanks are my turning failure and tool errors that cause separation or blow ups from using "chippy" blanks.
I have tried coloring the epoxy and evenly coating the tube before inserting. This produced a good visual result, where I could not see any bubbles in the glue. However, epoxy glue up still seems to be a problem for me. Many acrylic (I use that as a generic term) pens I've made, where I epoxied the tube in, colored or not, result in the tube separating from the blank. On close inspection, the epoxy is stuck to the tubes but separated from the blank. I can peel the plastic right off the tube and glue. I am trying now to weigh my resin and harder in tiny cups to eliminate proportioning errors. I am ready to give up on epoxy and use CA for all of my tube glue ups, both wood and acrylics. I like the TiteBond Medium wood CA and Stick Fast CA glue and have had success.
I have also tried reverse painting the interior of the blank with Testors hobby enamel. This works but I need to make sure the coating is even or the "brush strokes" can be seen. Painting tubes with enamel seems to make it possible to see the glue. I typically do glue up one day and turn the next. Painted tubes are left to dry 24 hrs.
I am going to try my acrylic artist colors next, based on some posts here, for reverse painting the blanks. Maybe the enamel is incompatible with the various plastic blanks? I think I'll also try cleaning the tubes before glue up with DNA. If that's not the answer, I'll only use opaque blanks where tube shadow or brass color doesn't matter.
Thanks for the input, this has given me renewed determination with perfecting my pens.

 

[jttheclockman]

I am sure someone can tell the exact story to reverse painting but it is done alot in lamps and glass and the photo is actual painted in reverse so that when viewed from the front it looks correct. So reverse painting just means you are painting on the inside of the blank as opposed to the front.

I will edit this post to address Marks comments. First welcome to the site.

The thing about epoxy they are not all the same. There are many types of epoxies used for different applications. We sometimes throw the term epoxy around so loosely that we all think there is one type. This is far from the truth. Without getting into all the different types I will say this you want a structural epoxy and I prefer one that is 24 hours or longer dry time. These 5 minute epoxy and not a strong as the longer open time epoxy glues. Look on the package to see what it is meant to do and what it is meant for gluing purposes.

Again I will say this if you paint the inside of the blank properly and the tube fits in without scraping the paint off why in the world would you need to paint the tube or even add paint to the epoxy. The answer would be you did not put enough coats to block the view of the tube or you scratched it when putting in the tube.

Also some epoxies will not accept the mixing of paints with it well. It breaks down the adhesion factor. So be careful when doing this. Everyone develops their own method and use what products they find work well for them. I like System III T88 epoxy and paint with Testors enamel paints. I use a Qtip to apply the paints. I allow 24 hours before the next process. I too am never in a hurry. Good luck.

 

[tomtedesco]

Reverse painting is the more productive and useful tool. Many times it is a necessity. If you do both the adhesion factor comes into play because of the layers you are putting between the parts being glued in. Plus build up of paint can mean the hole must be adjusted to accommodate the thickness. So painting the inside of tubes is the preferred method by many here. I would also suggest before painting to take some sandpaper and roll it up and sand the inside of the blank to get rid of the drill marks. Good luck.

I don't understand painting inside the tubes?? Do you mean inside the blank?

YES!

Thank you.

 

[lhowell]

I usually only paint the back side of the blank using either Krylon or Valspar spray paint meant for plastics. Sometimes I will use a Q-Tip to get inside the blank. The only time I will paint a tube is if I am doing a label casting or an Abalone blank.

The issue I have seen with only painting the tube is that if you have air bubbles or an oblong hole in a blank you will still see these imperfections whereas the painting the inside of the blank will usually hide these.

Never had an issue with adhesion but I will wait a full 24hours if not longer for the paint to have time to dry and cure.

 

[lhowell]

Attached is a good example of the contrast painting the back of a tube can make! Both of these pens are made from the exact same blank. The darker one I painted the back of the tube black and the lighter one was left unpainted. You can see the brass tube through the lighter one and see how much more depth the painted blank has in the colors. I dont think painting just the tube will give you this depth of the blank either. I think it has to come from the backpainting of the blank.

 

[Chasper]

I reverse the inside of the blank, not the tube. I put the blanks in front of a fan or outside in a warm breeze for a few hours, occasionally overnight. There is a big batch in front of a fan right now, I painted them early this morning and will turn glue in tubes tonight. I glue tubes with thick CA and let it set up for as little as 5-10 minutes before trimming the ends and turning. I've done it this way for thousands of pens and have had an occasional problem with the tube breaking away from the blank while turning, maybe one in a thousand.

I know that some resin blanks don't require painting, but my production process is to work in large batches. I'll usually cut about 50-100 blanks, drill all of them, paint all of them, glue all of them, trim all of them, turn all of them, buff all of them, and assemble all of them. While painting, I don't bother with skipping 2-3 blanks that don't need to be painted.

I fully reject the idea that blow ups in which chunks of a blank break off while turning are in any way caused by poor glue adhesion, or prevented by using stronger glue. Blow ups are caused by turning mistakes, if you gouge your turning tool to hard into a blank you can make it blow up no matter what adhesive you used.

 

[TonyL]

Hey Tony, I'm curious. Do you reverse paint wood and stabilized wood blanks?

Hi Jim:

I do not paint any 100% wood blanks. The blanks in my photos were wood and PR or Alumilte.

 

[Wayne]

Great discussion going on here!

This in a summarized form would make an excellent article. Adding the idea of a multi-colored dowel to determine choice.

 

[zebramz]

Thank you to John T. for the welcome and sharing your experience. I indeed have used the Q-Tips to apply the Testors enamel. That's where I found I needed to pay attention to stroke marks to avoid seeing the glue beneath. I'll look at the epoxies I have for specific types. However, I mostly use the mid cure epoxy from PSI. I do, as you, allow 24 hour curing. But with a modest background in chemistry, I will try to see if there is any info on possible interactions between enamels, epoxies and other paint carriers that may be incompatible with various pen blanks. Thanks again. Mark