Epoxy Primer Update!
Well, I mostly got all of the primer work done today. Ran into another small gotcha, I went back to Paint Max today to pick up another gallon of grey epoxy so that I would have enough to complete the interior and exterior and underside of the wagon. As it turns out, they only keep in stock one gallon and one quart of each color of epoxy primer. Since I had already bought the gallon, all that was left was 1 quart, which I bought figuring that if I didnt paint the underside and frame now, that I might have enough to complete the job.
The more I thought about it, I was planning to paint the underside and frame a satin black so I figured I might as well buy a gallon of black epoxy and give the bottom two good coats and call it good.
I am also thinking that I need to get a warmer reducer as well. Later in the afternoon, when the temp gets above 80 or so, I start having a major problem with over spray. It got so bad this afternoon that I decided to add more reducer to the last 20 oz I had in the gun. It sprayed out clean and wet with a great pattern. So either I need to reduce it more, or go to a warmer temp reducer. Painting has become more like chemistry these days…
My dear wife pitched in today and did a wonderful job of cleaning the ’39. It really got filthy when we encountered our last snow storm of the season coming back from Tucson. Tomorrow we take a day off and head up to Alpine for a great little car show and to spend some time with friends.
I am planning to have all the epoxy paint work done Sunday.
Primer Update!
After I got the wagon back from Beebe’s Custom Powder Coating, I spent the better part of a day removing the old seam sealer that was left on the car – primarily around the door edges, rear inner fender panels and the drip rails. My plan for covering the several acres of bare metal – did I say that this ’56 Dodge wagon is BIG! – is to start with the less critical parts like the inner fender panels, core support etc and use them to dial in the paint and spray gun.
Sometime ago when I was in the Dreaded Valley (temps are running close to 100 F so it’s now the DREADED VALLEY) among some other materials that I bought, I picked up a gallon of Martix MP-400 Epoxy with activator that was on clearance sale for $90. I had chosen Matrix because both Page Barnes and Steve Bryant thought very highly of the system because of the quality of the materials and their low prices as compared to PPG or Dupont. As it turns out, last year we had a new auto paint supply store; Paint Max Refinish Supply, open up here in Show Low that only handles Matrix, since the PPG supplier is in Flagstaff and Dupont is in Springerville its kind of a no brainer to stay with Matrix.
The tech sheet for the MP-400 Epoxy Primer specs that you mix it 4 parts epoxy to 1 part activator and 1/2 part reducer and my cheapie HF 43430 ‘Purple’ HVLP gun recommends 43 psi at the gun (10 psi at the tip) - I mixed up a gun load and set the gun up for a 6″ spray pattern at about 6″ to the panel with the mixture adjusted 2 1/2 turns out and tried this combination out on a panel, the result was a pretty heavy orange peel, the first thing I did was to boost the pressure at the gun up to 50 psi, which helped quite a bit. On the next gun load I tried mixing it 4:1:1 and went back to 43 psi – still some OP but it was flowing out much better as it set up. On the third gun load I stayed at 4:1:1 and boosted the air pressure at the gun up to 50 psi and cut the mixture back to 2 turns out, this yeilded a fairly nice result. The epoxy lays out wet and flows well as it sets up. The biggest variable to a good result is my ability to achieve a consistant gun speed and uniform panel distance.
The MP-400 Epoxy tech sheet requires a 30 minute induction time between the time it is mixed to the time that it is sprayed. It also looks like that it takes me around 20-30 minutes to spray 20 oz of material – or about an hour per 20 oz. To speed things up, I began mixing 40 oz of material at a time, after shooting the 1st 20 oz and reloading the gun with the remaining material, I mixed up the next batch of 40 oz. This worked pretty well – almost too well – once I got going, I didn’t really take a break for over 6 hours.
At the end of the day, I had sprayed 6 qts of material and had covered the inside and outside of the front inner fender panels, the core support, the inside and outside of the front fenders, inside and outside of the hood, the grill molding and splash pan, all of the window moldings, all the inside trim moldings, the tail gate and rear window and a bunch of brackets and pieces that I have fabricated over the past year.
Basically, all that is left is the inside and outside of the body and the chassis. I am guessing at the coverage, but I think I will need at least another 6 qts and possibly up to 9 qts of material to finish getting everything coated with epoxy. Yesterday, I went over to Paint Max and picked up a gallon of MP-480 – grey Epoxy primer. Paint Max does not stock the MP-400 grey-green primer that I have been using – the 400 epoxy contains lead chromate which gives it the green tinge to the color. My guess that it is being phased out due to the lead. PPG replaced their DP epoxy that contained lead with DPLF which is lead free some time ago. Most painters that I have talked to seem to think that the DP epoxy was superior to the DPLF, so I will have to see if I can tell if there are any major differences between the 400 and 480 versions of the Matrix line.
Oh, and the price of a gallon of epoxy is now $90 and $37 for a qt of activator, and before I start today, I will go back and buy another gallon kit to make sure I have enough material to finish the job over the Memorial Day weekend.
I’ll try to post up some photos soon.
Back From the Blaster!
I got a call on Monday afternoon from Beebe’s Custom Powder coating that they were able to get the body exterior, interior, hood and front fenders done and that I could pick them up at 5:00 pm. Frankly, I was surprised that they were able to get that much done in 9 1/2 hours! Having the right equipment really can make the job go quite a bit faster. Based upon my experience with my blaster setup, it would have taken me at least 5 times longer to get the car to where it is now.
Today I spent a fair amount of time cleaning sand out of the nooks & crannies and inspecting everything to see what ‘surprises’ showed up after the blasting that I would have to deal with. The main unanticipated problems were on the rear driver’s side of the roof. The roof in this area had a fair amount of rust, which ate through the roof just above the drip rail on from about the middle of the back window to just short of the rear door. The other issue was that the roof sheet metal just above this area had a fair amount of rust on the inside – looks like water had soaked the head liner in this area and over time rusted the inside of the roof. This created about a 12″ dia soft spot that oil canned when the blaster went to work on the rust on the inside.
The good news is that all of the areas that I had previously identified as being an issue did not get worse after blasting. I had some what expected to see most of the floor gone but was pleasantly surprised to find all of the damage was pretty much localized.
After the initial clean up, I used a wire brush wheel on one of my 4 1/2″ grinders to remove the remains of the rubber door seals and most of the seam sealer that the Dodge factory workers used to fill most of the gaps and body blemishes. I didn’t find any bondo on the car, but it does look like the passenger side had dents and scrapes in several places repaired using lead.
Later today, I got a call from Beebe letting me know that the lift & tail gate, interior trim pieces and the front grill bar and rock shields were done and could be picked up. So after a bit more detailing, I should be able to paint everything with urethane epoxy before tackling the remaining body work.
Off to the Media Blaster!
Well it hasn’t snowed in 3 weeks and we have been seeing daytime temperatures in the high 60′s to mid 70′s and there is no rain forecasted for the next week or so, so I decided now would be a great time to have the rust removed and paint stripped from the body and interior.
I contacted our local blaster/powder coat business Ed Beebe – Beebe Custom Powder Coating, who has had a fair amount of experience with auto and airplane/helicoptor stripping and arranged to get the Dodge to him today so that he could start on it early next week. He will remove the paint and rust from the exterior and focus upon getting the rust taken care of on all the interior panels.
As soon as I get it back next week I will give it a couple of coats of epoxy primer to protect it while I am finishing up patching the rust rot and filling trim holes. Its be great not having to look all at the rust and old paint! While it’s up in Taylor, I will use the opportunity to clean up the shop, which I am ashamed to say is filty with all the welding and grinding that I have been doing over the winter.
Patching the Passenger Front Floor
When I was installing the transmission coolers I had to relieve the floor on the passenger side to allow clearance for the transmission cooler hard line. The floor in the area where I cut the relief hole was in pretty bad shape so I decided to tackle both issues with one patch panel that would cover the hole, fix the rusted area and would provide a foot rest for the passenger.
I started by making a cardboard template for the new panel. Once I checked the template fit in the car, I transferred the pattern to a piece of 18ga sheet steel and cut it out with the plasma cutter. The piece was really too complex, at least for me, to layout in one piece so I opted to fill the hole between the top and bottom of the patch with a welded in panel.
I used self tapping sheet metal screws to locate the panel while I determined where to cut the existing floor. Once that was done I could make another template for the piece that would tie the patch panel to the old floor panel. Once the welding was completed, I did another test fit before attaching the panel to the floor with self tapping screws. Once the panel was located I pulled the screws one at a time replacing them with tack welds through both panels.
After all the screws were replaced by tack welds I went under the car and welded the patch to the old floor. I used my standard proceedure of placing tack welds about every inch and then knocking down the proud weld with my 3″ cut off wheel. The welds were completed by starting in the center and working toward the edges. Everything went well until I reached the bottom of the patch where it comes together with the floor and the transmission tunnel. Of course the old metal in this area was marginal and it of course blew out which forced me to do more than a few fill welds in the area until I reached good material.
Once I had everything patched up and the welds dressed I sprayed some primer on both sides of the patch to see how it looked. All in all not too bad for an area that will be covered on the inside and hidden by the engine and transmission on the outside.
The last piece of the puzzle falls into place! Once I had the sill and floor patch panels in place I could fabricate a repair panel for the bottom of the passenger side ‘B’ pillar where it suffered a considerable amount of rust damage. Luckily the pillar itself was still in good shape so all that was needed was a new foot to be welded to the bottom of the pillar and the floor.
I cut a patch panel from a piece of a little heavier 16 ga piece of stock and notched it so that it would fit around what was left of the bottom of the pillar. The 16 ga material cut nicely with the plasma cutter, but it presented a real problem when I tried to break the bends in to so that it would meet with the floor. Fortunately the patch was not that long so I used a bigger hammer to get it into the right shape.
Before welding the panel in, I sent a fair amount of time cleaning the rusted material from the bottom of the foot. The foot had been stamped from 14-16 ga steel and about 25% of it had rusted away. To add some strength back to it, I allowed a large clearance in the patch plate so that I could rebuild the missing material by laying down several layers of weld to tie everything together. It looks funny but it should be as strong as the original attachment, and in the end it will be covered by trim panels.
Fitting and Installing the Door Sill
To complete the repair of the passenger side rear quarter and rocker panels I need to fabricate a new door sill to tie the rocker panel to the main floor section. My initial approach was to cut the old sill back until I reached solid metal, which was about half way through the sill. I made a cardboard template of the new sill panel and laid it out on a sheet of 18 ga sheet metal. Once the layout was complete, I cut the new sill out using the plasma cutter.
Once the panel was cut out I clamped it to my table and used various pieces of steel and clamps to make 2 3/4″ bends in the edge of the sill to step it down from the rocker panel height to the floor height. I really do have to break down and by a 36″ break one of these days… it would cut my setup time down and make for better looking panels.
I did a little trimming here and there to get a good fit and drilled holes in the floor edge to weld through to attach the panel to the floor and to the center sill support which was welded to the bottom of the rocker panel. I primered the inside of the rocker panel prior to tack welding the panel in place.
After the tack welds had cooled, I used a 1/16″ cutoff wheel to dress down the height of the tacks before doing the final weld. I started in the middle of the sill panel and began stitch welding around a 1″ section at a time. I used the 1/16″ cutoff wheel to dress the weldment while it was still warm. Once the weld was cool to the touch, I began working from the center to the ends using the same 1″ weld proceedure and alternating from side to side. Once the center of the sill was completely welded, I clamped the drilled flange to the floor and proceeded to weld through the holes to the floor below.
Even with all of my precautions to minimize the metal shrinkage in the heat affected zone, the old sill metal did shrink more than the new metal, creating a valley down the center of the sill. If I had access to the back of the sill, I would have been able to stretch the weld using a dolly and slapper, unfortunately the sill completed the rocker assembly and I had no way to get a dolly under the welds.
In that the sill would be covered by a set of polished aluminum trim plates, I could have left well enough alone and lived with the valley; but I didn’t like the way it looked so I cut the sill out from the rocker panel to the floor flange. After fabricating a new sill I tacked and welded it into place using the same proceedure as before, however this time since I was welding to the edge of the rocker panel, I had no issues with warpage.
While I was at it, I fabricated a couple of patches to repair the bulkhead at the rear of the door opening. The bottom of the bulkhead had been rusted away with the floor. The patch consisted of a plate that went under the bulkhead and over to the floor flange and another patch that was welded to the bulkhead and the plate. To prevent any flexing in this area, I also added a small gusset between the floor and the fender well.
It was a little more work and took more time than I wanted to spend, but I am happier with the way it looks now.
Once the quarter patch panel is installed it will not be possible to primer the portion of the rocker panel covered by the panel, nor the inside of the panel, so I had to prime these areas before I welded the panel in place.
I am still not up to speed on using the finger control on my TIG so I decided to stick with the MIG and the same process that I have been using on sheet metal. Unfortunately after the panel is welded in, I won’t have access to the back side so that I can position a dolly to stretch the weld.
Fortunately, this area will be covered for the most part by the stainless rock shield so I wont have to spend a great deal of time on getting it perfectly straight, however I intend to spend a bit more time on it before moving on to fabricating the sill & B-pillar patch panels.
Installing the Rocker Patch Panel
Backer strips of 18ga metal were tacked to each seam and then tack welds were placed about every inch or so, starting in the middle of the panel and working toward the outside. Once the patch was tacked in I welded through the holes in the bottom of the panel to secure it to the extended floor panel flange.
After tacking the panel, I began welding at the center of the panel. With the MIG, I stitch welded between the 1″ tacks over lapping each stitch by 1/3 to 1/2 the bead. While the bead was still warm, I used a 1/16″ - 3″ cutoff wheel to remove the proud weld down to .010″ or so. Once the weld was cut down, I hammered the weld on dolly to stretch the metal before doing the next weld. After stretching the weld I air quenched the HAZ to make use it was cool to the touch before continuing.
I proceeded around the panel, swapping sides as I went until the panel was welded in place. To complete finishing the weld, I used a medium cross cut hand file to remove the remaining weld without over heating the panel. Unfortunately I had to get the ’39 ready for it’s trip to Tucson so I didn’t have a chance to complete finishing off the weld at this time.
Next up, patching the quarter panel.
Fabricating the Rocker Panel Patch
As you can tell from the photos the rocker panel from about the center of the rear door to the front of the fender well open was mostly gone. Since I didnt have much to work with, I decided to make a template of the panel, fabricate it and test fit it prior to cutting out the remaining rotted panel.
After checking the rough fit, I cut out the old section and used a step drill to remove the spot welds from the lower flange. After removing the old metal, I found that I needed to extend the inside rocker panel so that I would have something to attach the rocker panel patch to. The simple fix was a rectangular patch that was flanged and drilled across the bottom to provide a mounting point for the rocker panel patch. After a quick test fit, I welded the top of the panel to the new floor patch, then I ground the weld down so that I could shape the panel if needed.
I also welded in the patch that I had made for the rear body mount behind the door.
Before I could weld in the patch panel, I needed to fab a stand off brace for the middle of the door sill. This was welded to the rocker panel patch and then the patch was placed on the car and a few minor tweaks were made before tack welding it in place.
