Maloof Rocker - Finishing

At long last I have come to the final post on this project. It's been awhile getting here with the good times where things went smoothly and then there were times where frustration and bad words were directed at the piece.  Fortunately there were no problems that could not be resolved or worked around.

The last operation is finishing and because of material differences I will utilize two different types of finishes.  Since the construction lumber I used had knots, some other flaws, a few oops as a result of my practicing plus the wood is not really much to look at I decided to putty the flaws and paint it.  That also meant I did not have to sand it to the same level as the actual piece.  I am not sure where it will end up although my wife has hinted on putting it out on the front porch.  On the other hand I may keep it in the shop area.  In either case I wanted a durable finish so decided to use a fairly heavy body opaque deck stain.  The color I used is a dark green and with two coats I am happy with the way it came out.  One chair down and one to go.  As the photo shows it has ended up on the front porch although it may end up back in the shop later. J

Test Chair Done "Temporarily" on Front Porch

Ready to Start Spraying Finish

The actual chair gets a sprayed on nitrocellulose lacquer finish and preparation of the surface is key.  I start by using compressed air to get as much dust off as I could then wiped it down with a clean old tee shirt.  Next is to wipe down the workbenches with a wet cloth to capture dust, cover the spray area with a piece of cardboard and set the chair upside down on padded blocks.  The blocks are to put some space between the arms and the cardboard to minimize blowback of overspray onto the arms.  Spraying lacquer requires some protective gear.  I always wear a pair of nitrile gloves, a long sleeve shirt and a respirator with cartridges rated to remove the hazardous vapors.

To start I used a small air brush to do the bottoms of the rockers, arms and put a seal coat on the seat bottom.  Three coats of lacquer on the bottom of the rockers and arms gave me a nearly final quality finish and good base to work from.  I used 320 grit sandpaper to smooth the transition between what I already finished and the raw wood.  On the seat bottom I did a light wet sanding using 1,500 grit.  I have better luck wet sanding a finish as I don’t end up with hard chunks or corns of finish on the sandpaper.  However, you can’t wet sand unsealed wood as the water will raise the grain.   Also, now that the bottom of the seat has a seal coat on it I signed and dated the piece there.

Seal Coat and Underneath Side of Seat Signed

With the bottom of the rockers done I could flip the chair over and work from the top down.  I will use the larger Fuji HVLP (High Volume Low Pressure) sprayer for the rest of the finishing.  There are a couple of reasons for the change in equipment.  The seat is really too big to get a good finish with the air brush and the headrest nearly so.  Additionally because there are few sharp edges where I can break the application of finish I need to keep a couple of “wet” edges going and to do that need the speed of application I get with the HVLP gun.  However, to keep the overspray down I adjusted the controls from the broad fan shaped pattern I usually use to a smaller more circular one.   With everything ready to go I mixed up a batch of matte lacquer, thinner and retarder then shot one coat onto the chair.  With that done I quit for the evening.

I let the finish cure overnight and when I checked on it the next morning was shocked.  Almost none of the areas had the smooth surface I was used to getting.  The vast majority, probably 95%, of the finish in no way resembled what I had expected and was totally unacceptable.  The seat felt like someone had thrown 80 grit sand in the lacquer before it dried.  There were other problems but all in all it was a disaster.  In this photo the chair looks fine but trust me it’s worse than awful.

First Coat Finish Disaster

I had changed from the broad fan shape spray to a circular spray to minimize overspray and had adjusted the flow and spread to what I thought looked good and seemed to work on the test board I did.  Not so in actual practice.  My only recourse was to see if I could level the surface and retry.  Out came the wet sandpaper and I started to clean up the mess.  A few hours later I had probably removed 90% of the finish I had applied and had the surface back smooth.  I mixed up another batch of lacquer made some adjustments on the spray gun and gave it another coat.  Next day the results were better but I was still plagued with problems.  For the areas that were not acceptable out came the wet sandpaper again to clean up the problem areas.  Right now a wipe-on poly/oil finish looks really appealing.  In fact, for a couple of days I seriously considered stripping off all the lacquer I had applied and starting over.

I may be a little slow but I was not going to go through the spraying process again without making major changes.  Giving it some thought I decided to take a whole different approach.  To start with I used the small airbrush to spray the slats.  They are small, close together and the airbrush gave me more control and less overspray.  That worked just fine and once they were done I moved onto the arms and seat.  Here I made two changes from the earlier setup.  First, I went back to the fan shaped pattern I typically use.  Second, I altered the lacquer mix by increasing the amount of thinner.  This time when I sprayed the results were what I had expected.  That left the headrest, rear legs, seat bottom and rocker tops to do.  The next day I shot them using the same process and they turned out just fine.  There are not many photos during this phase of finishing for a couple of reasons, photos just don’t convey how rough the finish felt and I was preoccupied with finding a solution.

From here I only had to do a light final wet sand using an 8,000 grit pad.  If I had used a gloss finish I would have used the 12,000 grit pad.  Really the only thing it’s doing at this point is removing any dust that gets on the finish.  Now that the lacquer finish is done I am happy with it.  The matte sheen fits the piece and I know it will give me more protection than a wipe-on ploy/oil blend.  However, given what I went through to apply the lacquer and thinking about the probable use the chair will get I doubt that the extra protection is worth it.  Had I to do it over or if I build another chair (that's a BIG if) I probably will go with the wipe-on ploy/oil blend.

Completed Rocking Chair

Last step is to let the finish cure for a couple of weeks to let the lacquer gas off and then move it into the house.  How does it feel?  The back support is great, the arms are contoured and just fit, the chair as a whole is very comfortable and it takes minimal effort to rock.

The question that frequently comes up when I build pieces is, “How long did that take?” and on about half my projects I do not track my time.  However, this project is anything but normal so given the scope and that my estimate was for a 4 to 6 month build I decided to track my time.  I recorded the days worked, how many hours I worked that day, if it was on the test or actual piece and what I did.  First the disclaimer, this project had a lot of skills and techniques that I had not done and had to learn.  This was the main reason I built the test piece.  It’s better to mess up a piece of 2x6 construction lumber than a piece of 8/4 cherry.  Anyway from start to finish the project took 348 ¼ hours done in 102 working days spread out over 5 months.  Of that time 110 ½ hours were on the test piece and 237 ¾ hours on the actual chair.  The test piece has a lot less hours because it is not finished to as high a degree as the actual chair.   Remember all the sanding and my poor fingers. Also the patterns and jigs are all included in the actual chair.  For those into a more detailed breakdown here it is:

Item	Actual	Test
Arm	27.25	6.75
Back legs	15.25	11.5
Epoxy	1	0
Finish	13.5	0
Front legs	15.25	13.25
Headrest	16.75	9.5
Paint	0	6.75
Patterns & jigs	21.75	0
Plank work	9.75	0
Rocker	38.5	25.5
Sanding	19.75	0
Seat	27	20.25
Slats	32	17
Total Hours	237.75	110.5

The other question I get is would I do anything different and I can think of only three things. 

1. Given the problems I had with the sprayed lacquer finish I would probably use a poly/oil wipe-on blend.
2. While the chair fits me it is just a little tall to be comfortable for my wife.  If I were to build another I would likely shorten the legs a bit, maybe an inch or so.  
3. The rocker to leg joint is held together by ½" wood dowels.  I think I would seriously consider using ⅜” steel threaded rod instead.  That would leave a bit more wood at the joint for leg and rocker strength while the steel though smaller would be considerably stronger than the wood dowel.  I would use the threaded rod versus smooth rod to provide the epoxy with additional bonding area.

In the end I think that I should not give up my day job although from what I have read the chair currently made by Sam Maloof Woodworker Inc. runs about $25,000 and there is a three year wait to get one.

So for now I will sit in the rocker and relax - for a bit.  Then again I have my eye on another project that looks interesting....

dave

Maloof Rocker - Final Sanding & Flaw Repair

My poor fingers, I think they will never, ever talk to me again.  My thumb and forefinger were so tender that it was difficult to button my shirt.  I just had to let them rest for a few days after working on the transitions between the rockers and the legs.  Because there are just not too many flat surfaces on this piece that can be machine sanded this means that most of the sanding is done by hand.  

Fortunately for my fingers due to the type of finish I will use on the test piece it does not require any additional sanding.  However, the cherry still has quite a bit of work left.  I started by setting the chair upside down on the work bench and began with the bottom of the rockers working my way from 120 grit sandpaper to 150 and ending up with 220.  I will stop there until just before finishing then go over the whole chair one more time using 320 grit.  If I had gone with a coarser more open grained wood like oak I would probably stop with 220 grit.   However, my experience with cherry is that stopping at 220 grit still allows very fine scratches to show up through the finish.  One of the things that showed up as I moved to the finer grits was the occasional scratch that did not sand out.  The fix is go back to the previous coarser grit, sand that spot then go on to the finer grit, sand and see if it is gone.  If so, you’re good, if not repeat.  While upside down I examined the leg to seat joints and had to back up a bit.  What I thought was fine at the time ends up being not as good as it could be.  I think the experience of sculpting has taught me as I did more of it.  Anyway, I needed to refine the joints with a small file before doing the finish sanding. 

Finished Front Seat to Leg Joint

Rear Leg to Seat Joint - Not Quite Done

 As I was sanding the legs another wrinkle popped up.  The plugs covering up the screws are made out of katalox which is a lot harder than cherry as a matter of fact its Janka hardness is nearly 4 times that of cherry.  In addition I installed the plugs so the exposed part is end grain which is even harder.   The result is when I did the sanding the cherry being a lot softer sanded away quicker than the katalox.  This gave me a slightly raised plug rather than one dead on flush.  The fix is to use to use sandpaper backed by a hard surface to sand smooth.  Not really hard to fix but it did take some time.

With the underside of the chair done I flipped it over and started on the top side of the rockers and those infernal leg to rocker transitions.  From there I worked my way up to the seat and ended up with the top of the seat.  Not many photos here because the only thing more boring than shots of sanding is watching paint dry.  At this point I have only two things to do before applying a finish.  First is to fix the thorn in my side better known as the flaw in the side of the seat and second is to go over the chair with 320 grit sandpaper just before I put the finish on.  Have I mentioned that there is a lot of hand sanding on this project?

At this point I have two chairs nearly ready to finish.  The one made out of cherry and then the test one made out of 2x4 and 2x6 construction lumber.  They are nearly identical with these differences:

1. The construction lumber pieces are thinner at just under 1½” thick while the cherry is a fat 1¾”.
2. The construction lumber rocker has 5 back slats versus the cherry one having 7.  There are two reasons for that.  First is the splay angle for the rear legs on the test chair is less than the cherry resulting is less width at the headrest.  Second, I just did not want to make 7 slats for the both so the construction lumber chair has slightly wider slats but 2 less.
3. The construction lumber chair’s back is a few inches shorter because the lumber I had was not long enough to make the back legs the same length as the cherry.  It’s a test piece remember, and at first all I was going to do was test out the sculpting process for the seat.

Since I was still undecided on how to fix the flaw in the side of the seat I thought I would do some sample fixes and see if one stood out.  I took a leftover piece of cherry and drilled four ¼” holes (roughly the same size as the flaw) in it about the same depth as the flaw.  I then filled them using 4 different methods:

  A.  Super glue and fine cherry sawdust.
  B.  Translucent tan epoxy.
  C.  Same tan epoxy and 50% fine cherry sawdust.
  D.  Black epoxy.

I let everything cure overnight then sanded them flush and worked through the various sandpaper grits to 400.  When that was done I put the sample against the flaw and made an evaluation.  At this point "C" the translucent tan epoxy and 50% fine cherry sawdust looked the best. 

Next was to give the test piece a quick coat of lacquer to see how it looked against the dampened flaw.  I dampened the flaw to simulate the color after the finish is applied.  With these changes the fix that looked the best was "B" the translucent tan epoxy.  Since this epoxy is translucent it lets the structure of the flaw show through albeit softened but provides a smooth surface.  

With the decision made I mixed up a small amount of the epoxy, packed it in the flaw, let it set overnight to harden then carefully filed it down flush with the wood and sanded it up through 800 grit sandpaper. 

Finished Patch of Seat Flaw

With that done I started on the FINAL sanding with 320 sandpaper in preparation for finishing.   To reduce the darkening of end grain when I finish I hit those areas with 400 grit.  One good thing about the finer grits is they don’t sand the skin off my fingers quite so fast and my poor abused finger tips really appreciate that. 

Chair Sanded and Ready to Finish

After the sanding was done I thoroughly cleaned up the shop dusting off all the equipment, sweeping the floor and while I was at it dumping both dust collectors.  Since I will be doing the finishing in the shop I wanted to get as much dust cleaned up as possible.  Last steps are to vacuum the floor, blow any residual dust off the chairs then set the air cleaner to run for 6 hours and call it a day.

Shop all Cleaned Up and Ready for Finishing

Next up, the final step – Finishing

Maloof Rocker - Shaping the Rocker Ends & Leg Transitions

After spending a few minutes rocking it was time to get back at it.  First off is to work on the front or the nose of the rockers grinding both of them to the same distance from the front of the front leg.

Nose of Rocker Ground to Length

There is quite a bit of shaping on the front of the rocker that starts with grinding the bandsawn arc into a more finished form.

Top of Rocker Nose Rough Ground to Shape

The inside and outside faces are shaped next.  I made a paper pattern so I had a better chance that both would match albeit mirror images.

Next is to grind a smooth arc on the underneath of the rocker and transition the existing radius on the rocker bottom up the just ground arc.

Last is to grind a radius on the top outside edge, transition the hard inside edge up to the leg and clean up the rough surfaces.

With the front of the rockers done it’s time to move to the back.  They are simpler to do than the front ones.  First is to mark and cut them to length.

The inside face is then marked and ground flat to make a curved taper that flairs out toward the end.

Next a similar surface is ground on the top of the rocker.

Lastly, the inside hard edge where these two grinds come together is ground to continue the existing soft radius on the rocker.

Once the ends of the rockers are done that only leaves the transitions between the rocker and the legs.  The connection angles and leg shapes are different from front to back but the process is the same for all four.  I start with my trusty French curve to layout the transition, use the angle grinder to rough out, knock off the rough edges with the pneumatic grinder, clean-up with rasps and files then finally finish shaping with the 80 grit sand paper.  The end result looks so simple and obvious yet the time and effort to get to there really adds up.

Transitions from Legs to Rockers Completed

With that done I can move on to the final sanding and finishing, or maybe not.  There are two items that still need to be dealt with.  First, as I sat in the rocker testing it out I found that the arc at the front edge of the seat was a little sharp and needed softening.  I could not just leave it so I drew some guide lines and started in with the usual implements of destruction; pneumatic grinder, rasps, 80 and 120 grit sandpaper.   I am happy to say the front edge is now easier on the back of my legs and I can get on with the final sanding of that area. 

Second, is that #!@% flaw in the seat that I am going to have to address.  However, I still do not know what I am going to do with it.  Perhaps as I do the finish sanding I will have a moment of enlightenment.  Still at this point I am happy with what I have done so far.

Next up – Final Sanding & Flaw Repair