# Making Wooden Coasters, Branding with Branding Iron - Warping Issues



## shorterthanrich (Sep 22, 2012)

Hey guys,

I've been working on a project for a few weeks now, and am having trouble working out a solution.

I need to make about 1,600 3.5" x 3.5" wooden coasters. I've been planning to use simple finished 1/4" Poplar from Home Depot, since it's inexpensive, absorbent, and requires very little finishing work.

However, the coasters are being branded with a branding iron, and so far I can't seem to keep them from warping pretty aggressively, making them pretty useless for being a stable base for a glass full of beer!

Do you have any suggestions for preventing the wood from warping so much, or for un-warping 1,600 pieces after branding?

I can provide pictures if it would be helpful.

Thank you!


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## Dominick (May 2, 2011)

How thick are they? What's the species? I have a hard time thinking their warping. I have a hard time with cutting up 1600 of them. Wow!!!!!!
Maybe you could dry them in the microwave.
Always pics. It helps.


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## Dave Paine (May 30, 2012)

shorterthanrich said:


> I need to make about 1,600 3.5" x 3.5" wooden coasters. I've been planning to use simple finished 1/4" Poplar from Home Depot, since it's inexpensive, absorbent, and requires very little finishing work.
> 
> However, the coasters are being branded with a branding iron, and so far I can't seem to keep them from warping pretty aggressively, making them pretty useless for being a stable base for a glass full of beer!
> 
> ...


The wood is not as dry as you think. The branding iron is then drying out the branded side, but the non-branded side is still the same moisture content.

So the branding is creating the warping/cupping.

The solution is to use wood which is lower moisture content and ideally less relative humidity than the atmosphere when you do the branding.

An alternate, but time consuming idea is to rout the logo/graphic and paint the routed design. Less warping, just more time.


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## shorterthanrich (Sep 22, 2012)

Here's an album of images of the project. FYI, I branded both sides of these while experimenting. They're cupping towards the side branded darker: http://imgur.com/a/5tjbD

Thanks for the thoughts, guys. Dave, I think you're right. They're cupping towards the burnt side due to moisture removal - that's what I had been thinking.

And here are a select few to give you a general idea.

The coasters are 3.5" x 3.5"









And 1/4" thick:









Here's the wood being used. 1/4" thick Poplar from Home Depot. I think they call it "modeling wood" or something along those lines, as it isn't rough cut. That's all I know about it. I'd use a nicer wood, but since I have to make so many of these, it's extremely helpful to have something that's already thin enough to use and comes cut consistently. Cost is also somewhat important due to the quantity.









This is the quick rig that I set up for branding them:









Here's a coaster that didn't warp too badly. This is an acceptable piece: 









And here's what more of them look like. This one has warped quite a bit. It was worse yesterday, but sitting overnight seems to have helped a little. It's still not as flat as I'd like it to be for a coaster, though.









What do you guys think about the following options:

A) Drying them in the oven before branding. If so, for how long?
B) Drying them in a microwave before branding. If so, for how long?
C) Finding a better pre-dried wood, or a wood less prone to this issue. If so - any suggestions?

Thanks for the help. I'm starting to run out of time on this project. Deadline for all 1,600 to be finished is October 12th.


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## Dave Paine (May 30, 2012)

Thanks for the update.

The warpage was not on the side I expected. I thought the branded side would have lost more moisture, but the picture shows the non-branded side appears to have lost more moisture.

SD means Surface Dry which is not as dry as you think. It means < 19% but how much less is anyones guess. I think the next dry grade is KD Kiln-Dry which is < 15%. 

This is the moisture content when it leaves the place of manufacture.

Perhaps the branding is sealing this side so less moisture is lost as the piece cools.

Trying to apply controlled amount of moisture to get the piece flat is nigh on impossible.

Have you thought about branding a veneer and then gluing this onto a solid piece of wood?


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## shorterthanrich (Sep 22, 2012)

Dave Paine said:


> Thanks for the update.
> 
> The warpage was not on the side I expected. I thought the branded side would have lost more moisture, but the picture shows the non-branded side appears to have lost more moisture.
> 
> ...


Sorry, it's not very clear in the pictures. I branded both sides for many of these. On the ones where I only branded one side, it did cup towards the branded side as you'd originally thought.


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## DaveTTC (May 25, 2012)

My 1st thought is the large surface area you are branding. 

Can u get the iron hotter and have a quicker burn. If you could burn simultaneously from both sides I believe you may not have an issue. 

I don't know how you go about making your iron but for larger areas of black could you use a cross hatching pattern to reduce the surface area being branded. 

Finally the areas that are not branded in the centre are probably being heated by 'trapped' heat from your set up as there is, from what I can see, no cool air in those central areas. 

My opinion is you may benefit from an iron rebuild. 

The one that passes QC looks good

Dave The Turning Cowboy


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## Dave66 (Apr 6, 2012)

You probably need to brand a whole lot less of the surface. Heat will distort wood and you're putting a lot of heat on one side. A lot of heat is gonna cause a lot of distortion. The poplar is probably dry enough. Your problem is too much heat. 

A thicker piece of wood would probably distort less, as would a harder species (maple?).


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## joek30296 (Dec 16, 2009)

Since they're only 1/4" thick, I'm thinking plywood wouldn't warp as readily as solid poplar. Birch plywood, 1/4", shouldn't be too expensive 
and you should be able to get over 300 per sheet.
You might try a scrap and see. Just my thoughts.

Joe


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## Bill White 2 (Jun 23, 2012)

Brand the wood BEFORE ya cut it into parts, and alternate the branding areas/sides.
Give that a try on some sample pieces.
Hey! It couldn't hurt to try. 1/4" is pretty thin for poplar or any soft wood.
I forgot to ask. Are ya not putting a finish on the coasters?
Bill


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## FrankC (Aug 24, 2012)

My concern with these is what happens when a sweaty glass of beer sits on them for a while and they get wet on one side, unless they are well sealed you may have a warping problem later on as well. Baltic birch plywood seems like a more stable material.


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## DaveTTC (May 25, 2012)

Please let us know how it all turns out in the end and what the solution was.

Dave The Turning Cowboy


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## shorterthanrich (Sep 22, 2012)

Hey guys, sorry for the sparse replies - just lots of work and experimentation going on here. Thanks so much for all of the ideas - you all are tremendously helpful.

I've decided that it's going to be next to impossible to get that thin of a piece of poplar not to warp under such high heat, and took up your suggestion of using plywood.

I tried the Birch plywood, but unfortunately it was a bit too "splintery." It's almost as if it's a thin veneer on the top layer, and cutting the pieces chips at it. 

Instead, the somewhat generic "Sande ply" from Home Depot seems to be working perfectly. I feel sort of ashamed to be using something so generic, but it's looking great and holding up against warping what-so-ever.

So, the final step is to figure out something that I'm least experienced in: what should I use to seal it? Polyurethane, spar urethane, polycrilic, lacquer, tongue oil, linseed oil, or something else?

My priority with the finish is mostly to protect the wood from stains and warping, and resist the chemicals that will inevitably be used to clean it. I'm leaning towards Plyurethane varnish, but your opinions on the matter would be greatly appreciated. Any specific brands or pitfalls when it comes to poly that will stand up to the difficult life of the beer coaster?


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## shorterthanrich (Sep 22, 2012)

Any advice at all on a finishing product?


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## Dave Paine (May 30, 2012)

I am happy to see an update.

The challenge with a plywood solution is to seal the edges which are a combination of face and end grain.

Poly may work. Only time will tell for how long.

Alhough this is an interior use, there will be a lot of exposure to water. The drinks, the cleaning, condensation pooling, etc.

You may want to experiment with exterior paint - but WITHOUT the pigment. Ask for dark paint base, usually #4. This should be available in acryllic or oil-based. I think oil-based may work best.

Here is an article.
http://www.hardwoodlumberandmore.com...ar-Finish.aspx


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## BigBull (Feb 10, 2010)

I think I'd look into some epoxy. It would dry clear 9 so the logo shows thru). and if completely covered it should seal and hold up to some cleaning.


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## DaveTTC (May 25, 2012)

How did this one go, have you finished it?

Dave The Turning Cowboy


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## shorterthanrich (Sep 22, 2012)

Thanks for the help everyone. I ended up using a spray poly for the sake of both time and for the finished product. Here's how everything came out:

600 of 1,800 coasters laid out for drying:










The final pine-wood packaging:









Everything as presented in the package:









Some glory unboxing shots from customers:






































Overall, I'm extremely happy with how everything came out, and would like to thank you all again for your help. Next time around we'll need as many as 6,000 coasters, so I'm not sure I can tackle it myself!


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## DaveTTC (May 25, 2012)

Impressive, the whole package looks good.

Dave The Turning Cowboy


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