Saturday, 30 September 2017

Modifying the new cross members

As I mentioned in the last post, I now have some new 'German' cross members which I am going to be using as a foundation to produce some year correct ones (i.e: '64 - '66 Beetle). They will not be 100% accurate, but will come pretty damn close. I have given this a lot of thought and it seems like the best approach as mid-sixties cross members simply don't exist as a repro item. Cross members commonly rust out on a vast majority of old bugs, so getting hold of a rot-fee OG section is almost impossible and only exist on rare foreign cars that have been driven exclusively in dry climates. Anyway, I have not seen this particular modification done before, so hopefully this detailed overview will be of some help to others who may be interested in doing the same... 

I began by drilling out the spot welds and separating the reinforcement section from the main panel. This gave me better access and allowed for a neater job:

On the main panel I smoothed out the unnecessary hump by simply cutting around it and welding in flat sheet steel:

These repros include an access hole to the heater channel. This was not something that mid-sixties cross members had, so I welded it up:

The rear edge needed a new profile adding to accommodate the correct upward angle of the heater pipe. After careful measuring and scribbling a few notes I mocked up a cardboard version of the hump I was trying to recreate:

I then transferred the measurements to sheet steel and cut out the geometric net:

After some folding on the vice and a quick zap of the MIG welder to close up the slits:

Linished back and compared to the original:

tacked into place on the cross member once the appropriate recess was measured and cut out:

After being fully welded, tweaked and dressed:

Just after the hump is a small section that is bent down on the original. I had to improvise around this section as access for clamping was tight. After some careful tapping with the hammer (remember that man light taps are better than fewer hard bashes), I got the 90 degree bend I was after:

Next task was to alter the heater pipe hole to the correct oval shape:

And trim the return flange to match the original (which terminates about halfway down):

At this point I roughly bolted up the heater channels to the pan and added the crossmembers. The fit wasn't as good as I had hoped and I was unsure at this stage if this was due to the restored pan being off or it the location of the mounting holes in the new panel were incorrect. After some head-scratching I discovered that the lower holes were not spaced apart close enough. There was a 5mm difference compared to the OG spacing. 

To correct this I elongated the hole;

Then using a copper backer I welded the other end to close up the gap slightly:

After some Dremel tool action I had it all looking correct again:

I then shot blast the entire panel before plug welded the mounting reinforcement sections back into place:

Moving on to the thicker supporting rear panel that I removed in the first step, I proceeded to cut out the unnecessary hump and chopped off the rear section that I assume adds strength to the underside of the boot corners. However, this was not present on the originals so I determined that it was surplus to requirements:

Welded in some flat sheet to replace that bump and welded up the access hole that was also present on the main section:

I welded up this little join to add a bit more rigidity:

Shaped the mating flange that will eventually fix to the inner side of the rear wheel arch:

Shot blast the reinforcement panel and got it realigned the best I could to the main section. I decided not to plug weld the pieces together at this point, just in case I needed to adjust anything further down the road. So, here is the nearly finished article just prior to spraying with zinc primer:

Now to do the same on the other side...

Friday, 8 September 2017

Rethinking the rear crossmembers

Although I had previously acquired a pair of genuine VW rear crossmembers I have since decided to take another route. Those Mexi ones could be made to work but have a different overall profile to the mid-sixties ones and are more square/angular looking. They also lack the mounting stud that locates the bottom hole of the rear wing as they are designed for later cars. One other annoyance is that they don't fit up to the Klassic Fab heater channels without trimming down the mating flange (located at the and of the channel) considerably. Those channels were expensive because they are high quality and accurate; I really don't fancy chopping them about!

Fortuitously a new reproduction crossmember has recently appeared on the market from out of nowhere and is supposedly 'German' quality (always a bit sceptical about that term) and made from factory gauge steel. I have seen them being used in a couple of other restorations, but have been unable to find out a lot of information about them. So, I contacted VW Heritage (one of the only UK stockists) to see if they had more about the manufacturer and swiftly received the following reply; "We don't have the manufacturers name, but we source them from a German supplier". Oh well, despite being no clearer about their origins I took the plunge and ordered a pair. I knew that they would still need modifying as they are made for cars up to '63, but in general they are a lot closer to mid-sixties OG ones and therefore a more logical basis to start from. I was quite impressed when they arrived, thick steel and super crisp pressings. Here is how they visually compare against the genuine Mexi (grey) ones, you can clearly see how much they differ:

I salvaged a few things from my old crossmembers that will be transferred over to the new ones. Firstly, I needed to remove the heater pipe. I shot blast the area so that I could reveal where the factory welds were:

I then carefully worked my way around the pipe (on the front and backside) with the Dremel tool equipped with a small cutting disc until it came free:

Next task was to separate these little reinforcement pieces from the top of the bolt holes using the spot weld cutter:

After a quick clean up they are ready to be reused:

Utilising the remains of the old crossmembers as reference I am able to study what I need to do in order to make the new panels close to OG and devise a plan of action. In the next post I will go into detail about how to adapt the new cross members to make them correct for a '64 - '66 Beetle...

Tuesday, 29 August 2017

DIY Powder Coating

What, no posts for two whole months ...what gives?! Well, I assure you that I have been progressing the car on several fronts, but I just keep coming up against panel alignment issues and other such demotivating frustrations, hence why I have not posted for a while. To reignite my enthusiasm I decided to focus my energy on something else for a change and thought it would be fun to turn my hand to power coating. I've always loved the way things looked in powder coat, but I didn't actually know anything about the process until doing it. I find that getting actively involved is often the best way to learn. 

To start with I spent an eternity methodically sandblasting and degreasing all of these miscellaneous components:

I then masked off certain areas using high temperature polyester tape and silicone plugs.

A word of caution: I ordered the masking plugs off of eBay whilst at work. I do not recommend searching for the particular key words 'silicone + plug' whilst visible to passing colleagues in an open plan office ...ohh, sh*t! Delete screen, DELETE SCREEN!

Using latex gloves to avoid contamination, I careful packed the parts into a paper lined shoebox and took them half a mile up the road to the workshop of my buddy Chris at 'Moody Moto'. He hand builds some incredible custom chopper motorbikes based around old Ducati engines and is one talented mofo (check out his sublime handiwork here). Anyway, he happens to have a basic powder coat setup and an repurposed domestic oven in his workshop for baking the parts. I bribed him with a pack of beers and set about it.

I hung the parts using conductive wire (thick welding wire in this case) from the removable oven shelf:

I opted for a black (RAL 9005) semi-gloss polyester coating manufactured by Interpon. I was concerned that full 'mirror' gloss might leave the parts looking a bit over-restored, so a more satin finish felt appropriate for my needs. The application of the powder was actually pretty simple. Once the electrode of the gun was attached to the metal shelf, the powder was liberally sprayed over the parts in a wafting motion. The electrostatic process attracts the powder particles to the charged parts leaving a layer of powder evenly distributed across the surfaces. I did it in 3 batches to avoid overcrowding and to ensure I could angle the gun sufficiently to coat all of the parts sufficiently:

Carefully the fragile dry coated parts were transferred to the preheated oven and were baked at 180 degrees for around 20 mins. Here is the magic result:

Look at that tasty serial number, so crisp:

A few more to feast your eyes on:

I am beyond pleased at the outcome as the cured finish exceeded my expectations. About 85% of the parts came out faultless and the remainder will need some minor touching up. Not bad for a first go! I have plenty of powder left and a few more parts that I think I will blast and coat in the near future; it would be rude not to!

Big thanks to Chris for allowing me to use his gear and guiding me through the process!

Monday, 26 June 2017

Stud patch process

Remember a couple of posts back when I was patching the stud line and had made a replacement captive nut section but opted not to weld it in for some vague reason? I didn't admit it at the time, but the truth is that I made a complete mess of the rear of that patch panel whilst attempting to weld the captive nut into position. Originally I drilled the 4 corners of the weld nut and tried to plug weld through them. However, the intense heat actually melted away edges of the nut and left a less than desirable outcome. It looked like crap, so forgive me for not sharing a photo of that abomination! After some contemplation, I decided to remake that patch taking a different approach to affix the nut. Essentially, I would start out with an oversized off-cut of steel and plug weld the captive nut in place neatly before spending the time trimming it down to the exact shape required. Less time wasted if I happened to balls it up again...

I used a scribe to trace round the shape of the old piece (on the other side) and locate the position of the main nut hole (10mm). I then drilled out 4 smaller holes that I would plug weld through:

As you have probably gathered, for this method I welded from the front side into the captive nut, rather than from the back through the nut.

M8 captive nut (Hooky's) camped into position and perfectly aligned ready for plug welding through the four holes:

Welded and ground flush to a tidy finish:

Good penetration on the underside and most importantly, no edges burnt away:

Now that I was content with the outcome I took my time carefully shaping the patch:

Positioned on the wheel arch:

Welded, finished n' linished:

Moving on around the arch I deemed that the next captive nut was saveable as the steel still appeared thick and the surrounding area was not sunken or protruding. So, I welded up the slits (left over from my previous patch repairs) and smoothed everything back:

The next captive nut, complete with the partial remains of an old seized bolt, was completely shot and promptly chopped out :

This revealed quite a bit of surface rust behind it on the inner (soon to be inaccessible) panel. I shotblast the area the best I could to get it back to clean steel:

Then sprayed a couple of coats of zinc primer to keep it protected:

Whilst that was drying I knocked up another repair patch using the above approach. Fabricated this one in literally half the time now that I know what I am doing:

Couple of tacks to hold it in place:

After waving the magic wand:

This wing mounting area is becoming a lot more solid now. A lot of work has gone into it (with more to come!), but I think the results are worth it: