I was not happy with the results, but I was encouraged by the proof-of-concept test to replicate the top trim panel I wrote about in the last post. After pondering my experiment for a week or so, I decided it was worth taking a chance on another attempt.
Learned a few things from the first go-round. One was that I needed heavier paper to make the template/pattern. Last time I used brown paint masking paper, and it was too light.
So I went to my local artist supply store and wound up with a pad of 50 lb sketch paper. Not too heavy where it wouldn't be pliable, yet not so thin as to tear easily.
I cut it up and taped it the the press and traced the pattern. Using, I might add, one of the nice Derwent graphic pencils I bought.
Here's the freshly traced pattern on the bench. Much more accurate than the last one.
After cutting out the pattern, I used spray contact cement (3M "44" if it matters...) for a temporary bond to attach it to the press head. Spray it lightly on just the paper, then stick it on. We need to be able to remove it for use on the aluminum sheeet.
I found a number of spots where the pattern didn't exactly fit, so I just glued some small patches on, and then cut around them to make the pattern more accurate.
I let the pattern dry a bit so it wouldn't come apart, then I carefully removed it by working my trusty X-Acto knife under it.
You have to be careful because the knife could easy cut the pattern. Do a little at a time, and "roll" the knife a bit, using it like a spatula rather than a knife. Since there wasn't a heavy coat of adhesive, it came up easily and with no tears or cuts.
Now I put the pattern down on the aluminum sheet. There was still enough tackiness on the paper from the adhesive that it stayed in place.
Then I traced the pattern with an ultra fine sharpie.
On the aluminum: last time I used whatever sort of aluminum they had at Home Despot. Part of the problem was it didn't really sit down tightly on the press, I think due to the type of aluminum it was. Of course, the label on it in the store just gives its thickness, not what type of aluminum it is.
So I went online to McMaster-Carr, which is not only an unbelievable place to buy fastners, materials, fittings, you name it, but it's also a tremendous educational resource. In this instance, I decided to get some 1100 aluminum sheet. This is a soft alloy, and relatively thin. I bought a couple different thicknesses and hardnesses to try. I wound up using the sheet with 15,000 psi yield strength. A 5,000 psi yield sheet was a bit too soft - I could very easily bend or dent it. (But it would be great for toymaking I bet...ha ha).
If you follow that McMaster-Carr link, you'll see what I mean about them. I learned a lot about different aluminum alloys, and I got exactly what I needed, no guessing. What an amazing place.
Now to cut the pattern.
I had found in some experiments that my tin snips tended to deform the metal near the line I was cutting. Of course, I wanted to be as close to the line as possible, but couldn't be dented or bent.
So I came up with a two-part approach: first I made a light cut with a Dremel metal cutting disc, giving me a groove to follow, then I cut with the snips.
This is the groove cut with the Dremel. And I'm following it with the snips.
This let me have a reasonably accurate line to follow, and by cutting some of the thickness away with the Dremel, the snips cut through the aluminum very easily, and didn't dent or deform it.
Here we have the trim piece cut from the sheet.
One other thing I learned from the last time was that the piece should be cut to shape before it's polished and the engine-turned pattern is applied. Last time I did that first, then cut the pattern to fit, and the polish and engine-turning got wrecked a bit.
Now we take the trim piece and fit it to the drill press head.
Side note: in the parts list for the drill press, this piece is referred to as a "panel." And the price for the part is listed as 80 cents! In today's money, adjusted for inflation, it's still only $7.55. If I only had Doc Brown's DeLorean to go back in time and order one from my local Sears...even at the inflated price I'd be ahead of the game!
Instead, I am stuck trying to fabricate one with my mediocre metalworking skills.
To get a closer fit, I marked the panel then carefully took off material here and there with a grinding stone on the Dremel.
After the fit was good, I polished the piece with my 3" random orbiting polisher and Mother's Mag and Aluminum polish. Nice and shiny after that.
Then it's over to the small drill press (anticipating that this one will be The Big Press...) to do the machine turning.
You may recall my homebrew fence to align the swirls on the metal in the first attempt.
This time, I just marked the table as to where to place the fence to get the correct distance between rows. After experimenting with 3/8, 5/16, and 1/4 Cratex sticks, I'm going with the 5/16 diameter. So I'll run rows 3/16 apart. That will give me some overlap on the swirls but yet the centers still show.
For the horizontal spacing on the swirls, I'm confident enough to do them freehand since I've done a few hundred (!) of them in my experimentation - just eyeballing the distance of swirls as I go down a row.
Here's part of the first row already done.
I'm using that 5/16 diameter Cratex stick, medium grit. I tried medium and fine grits and medium looked best to me.
And now I have a selection of sticks for future projects...sigh.
The final piece in the puzzle is the speed of the press. Last time I had it set for like 800 rpm. Cratex recommends 1450 rpm. My press would only give me 1200 or 1700...so 1700 it was. This press is a 10" Delta Shopmaster, inexpensive and pretty sturdy, but there is not a lot of speed variation - not that I change speeds a lot.
Here it is after the engine-turning. I also polished it again with the machine and it looks pretty good.
Ok, I'll admit I wouldn't mind another attempt, but man, this has taken a couple weeks in total and I have to stop somewhere.
Now for the final fitting.
The aluminum is soft and reasonably pliable, but the curve at the front is tight enough that it needs a little more encouragement. So we apply some heat from a propane torch.
Over to the press, try a fit, heat it up some, bend, etc., until it follows the contours of the press well.
Now it sits nicely on the press, but there are a couple places where I want it to really snug down closely.
So I mixed up some JB Weld and put it on the press...a thin layer and just on the press itself, not on both pieces.
Used a couple of my guitar repair cauls and cut a quickie custom caul for the top curve and clamped it down.
This sort of thing is why you can never have enough clamps. I could use a few more of those really big red ones...note to self.
And you can never have enough tools. There are two screws that go through the back corners of the panel. I need to drill holes from the inside so I can mount them.
The angle is tight and I can't get my drill into the space in the head, so I reach for my trusty right-angle drill attachment. This is something you won't use a lot, but you'll be really glad you have one when you do need it. It attaches to your drill chuck and then has a drive and chuck of its own.
Not the best made thing in the world, the chuck is junk and the whole internal assembly is sloppy (got this one at Despot, get what you pay for) but boy it's a lifesaver when you need it.
Now you see what I mean. I couldn't get to the holes straight on, but with the attachment, I can just make it.
The red thing at the top of the picture, by the way, is the handle for the attachment. You can grab it if needed, or you can remove it if you need clearance within the space you're working in.
The fasteners go into the ends of the panel, and replicate the way the original attached.
I used stainless drive screws and tapped them in with the plastic tip on my fret hammer. This one is about to be driven in all the way.
The manual just calls these "screws." I wonder if they were standard threaded screws. The holes were not threaded; maybe the screws were a press fit and worked their way out over time? I mentioned I've seen many of these presses where the trim has gone missing. Maybe that's why? The screws fell out, the trim panel fell off, and got lost or misplaced over the years.
In any event, I have now restored mine as best as I am able with my limited skills.
Here's a shot of one side. I think even if you didn't machine the aluminum and left it plain, it would look better than not having trim at all.
This is a real art deco look and I love it. A functional took, but with a nod to the art and style of the time. What a classy design.
Today that trim would be cheap plastic instead of aluminum, and the head would be thinner steel instead of cast iron.
From the front.
It's not perfect, but it's very presentable.
Now I can finally start reassembling the press!
The complete restoration saga
Part 1 - BeginningPart 2 - Electrolysis to Remove Rust
Part 3 - Grinding to Remove Rust
Part 4 - Leveling Base Table
Part 5 - Recreating Model Number Label
Part 6 - Refinishing Base
Part 7 - Removing Motor
Part 8 - Motor Disassembly
Part 9 - Motor Bearing Replacement
Part 10 - Start Capacitor and Motor Reassembly
Part 11 - Removing Threaded Jacobs Chuck
Part 12 - Spindle Removal
Part 13 - Quill Disassembly
Part 14 - New Quill and Spindle Bearings
Part 15 - Engine Turned Aluminum Trim Proof of Concept
Part 16 - Engine Turned Aluminum Trim
Part 17 - Cleaning and Polishing Hardware
Part 18 - Jacobs 633C Drill Chuck Restoration
Part 19 - Cleaning and Polishing Column
Part 20 - Reassembly Begins
Part 21 - Restoration Completed
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