Thread: Filling Holes in the Base of a Woodfast 'Universal Woodworker'

Back in July of 2020 BobL gave me a Universal Woodworker along with most of the accessories that Woodfast originally offered with the machine. It and they needed a bit of work - https://www.woodworkforums.com/f153/...68#post2198168

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After six months of distraction I'm back at work on the Universal. The machine's 1.6mm thick steel pedestal base has a total of 21 non factory fixing holes in it where switchgear and conduit were attached. I would like to fill the holes in a neat and hopefully undetectable fashion prior to repainting the base.

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A while back I attempted to fill some 4mm holes in the 1mm thick steel door of a GMF grinder pedestal. I used a Mapp gas torch to silver solder in place a brass plug ( a modified countersunk wood screw ) . The heat caused the door to buckle. I now have an oxy/propane torch but I'm hesitant to try my hand at silver soldering plugs in the holes due to fear of distortion.

My present thinking is to use JB Weld epoxy to adhesive fix a small thin steel disc to the rear of each hole and fill the hole from the outside face when the epoxy has cured.

Does anyone have any suggestions?

Bob.

Personally I would try to find a panelbeater and get a quote to mig it up and grind it smooth. Ask if they work in the afterhours beer economy.
Rgds,
Crocy.

That would be my thought too - fill the holes with MIG or (my preference) TIG. Paradoxically, the sooner you can get the heat on and then off the less distortion you will have. A gas torch is too slow and gives the surrounding metal time to heat as well. If only you were local, I'd have a go for you.

Michael

Hi Bob,

Something I saw on a U tube hot rod build channel.

Use a small diam wire on your mig. Your holes look around the 6mm mark.

Use a bit of copper sheet with a handle to back the hole. The area around a hole must be cleaned to a shiny finish.

The copper sheet say 1.6 thick is shaped to flush to the back of the hole. the MIg is used in "squirts". The molten steel deposit will not stick to the copper.

In the vid ,the welder had a helper to position the copper flush up against the inside surface.

Pull the trigger for a second and then stop. Let the deposit solidify. Do this over and over until the hole is filled.

Buff off with a flap wheel.

Pre weld cleanliness is essential ,no rust. paint. Just shiny metal.
Don't localise the weld areas. Do one and then an opposite as far away from each other as you can. This will minimise heat distortion.

Grahame

MIG with a copper backing bar behind the hole. The weld won’t stick to it and it cools the molten filler and makes it very quick and easy to fill the hole.

Edit: Grahame beat me to it.

Just to add - I use a solid rectangular bar for flat areas, but a piece of copper water pipe flattened or formed to the curve of the surface also works well. Particularly if you need to get it up inside a section where your hand won’t fit.

Steve

The other thing that would work fine for those size holes is some of the fiberglass filled body filler from the likes of Supercheap.
The strands are very fine - not like working with fiberglass mat or chopped strand. More like the fibers from a fine woven cloth.
Nice and clean with a quick sand to give the bog something to key into, then tape over the front of the hole and apply filler from the back.
As long as you’ve got say 10mm + past the edges of the hole on the back it should be plenty strong enough. Doesn’t need to be very thick as the glass gives it strength so just feather it when applied and sand to blend once hard.

Steve

I agree mig welding and a careful flap disc to finish it.

If you don't have a welder, look up quick steel, there are a few brands with different names but are all good.

It comes in a small roll/tube for around $15 from memory 6 months ago, you cut a slice and mix it in your fingers neading it. It has a grey outer and black inner, so a 2 pack.
Once set it can even be drilled and tapped.

I have used it on odd jobs over the years and has always performed well.

The Auto parts guy that put me onto it probably 15-20 years ago was at a motor cross race meet with his son, his son broke a clutch lever and he didn't have a spare, so he used quick steel to bond it back together for the next session.
Not only did it last the next race, it was left in the toolbox for a spare.

Edit
Just to add it can be filed and sanded once set, which is usually within half an hour.

So that the filler doesn't fall out when sanding (a bit too heavily), SLIGHTLY countersink both sides, so the filler acts like a rivet.
Kryn

I'd agree with what's been said regarding MIG welding the holes up. While a Copper block is the best option, Copper is rather expensive and not as easily available as some other options. A bit of 6 or preferably 10+ mm Aluminium does a pretty good job, although the finish on the back is better with Copper if that's a particular issue and you cannot get access to sand it off. Use either a wet rag or a spray bottle full of water to cool each welded hole as you go to help prevent rippling of flat panels.
Where I will go against the general flow is the use of flap discs. On a flat surface, you will get a much better (flatter) result by using a 5" backing pad and 5" sanding discs on an angle grinder - make sure that you keep the disc flat and don't just use the edge like most seem to. I was once a flap disc disciple, but once I was introduced to 5" sanding discs and learned to use them properly, the love affair with flap discs was definitely over.

Mig is the way to go.
I have 10 x 75 x whatever length fits bits of buzz bar for back up. (Sons a sparky).
However, especially if the holes are tapped and can be cleaned bog should stick ok to the internal thread.
H.

Thank you All for your replies and suggestions.

While most of you recommend welding the holes closed, I don't have a MIG or TIG welder nor do I possess the ability to use either with any competence. It has been 29 years since I used a TIG welder and longer for MIG.

The Woodfast will not fit into any of our vehicles thereby knocking on the head the idea of taking the machine elsewhere for repair.

Given the 1.6mm thickness of the steel I could possibly tap the holes with a fine thread such as BA and using Loctite RC/635 retaining compound, adhesive fix in place some theaded inserts which could then be carefully filed flush.
Or even forego the inserts and use a combination of gentle countersinking as suggested by Kryn and threading to retain an epoxy filler.

In a discussion elsewhere I mentioned to Ralph 'Caskwarrior' that I had used Devcon Steel Putty to repair the magnesium crankcase of a KTM I owned back in the mid '70s. Held together for two years worth of competition. I imagine Devcon or JB Weld would cope in the stationary base of of a woodworking machine albeit one that might vibrate a bit.

I will let you know how I fare.

Bob.

By the time you C/S both sides, there won't be much material worth threading.
Kryn

I recently blanked of a hole by making a stepped disc that I glued in place with JB weld. The disc was big enough to provide plenty of glue area on the back but the front was level with the original surface.

Sorry have come to this thread late but given your limited means of welding/brazing then JB Weld or similar will do a good job. I find it more expedient than brazing or welding for cosmetic stuff as there's basically no setup (aside from making sure the holes are spotless clean) and relatively quick cure time.

The epoxies work well for non stress or minimal vibration metal but that said, they are pretty flexible all the same and should be OK for what you describe

Won't mention the times I've brazed or welded thin holes only to come unstuck either warping or trying to flatten down welds for priming.....now, I just reach for the epoxy (when it's going to be painted and again I stress, not structural) ...stick some hard waxed cardboard as a backer under the hole with some masking take then fill it over - when cured just sand it flush and away you go.....lot easier............good luck

Holes sandblasted and backed with four layers of masking tape then overfilled with JB Weld epoxy. Sanded flush upon curing, followed by a thin swipe of body filler and an overcoat of etch primer.

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A better result than I expected and better than being told to shove off by the local panelbeater.

BT