I have a DeVere wall mount 5108 I use for printing my 8x10 negatives, but I've always sort of wished it was a floor standing model. Recently I've been doing some research into converting it to a floor standing model, but I haven't come across someone getting rid of the base yet, and buying the base from DeVere costs more than I'm wanting to spend. For that reason, This past weekend I started toying around with the idea of building a floor standing 8x10 enlarger chassis myself.
The basic design is similar to the DeVere in which all the focusing controls (lens stage, head, and table movements) can be controlled from the table. The table has 3 wheels mounted to the front, which turn pulleys mounted to the table's carriage which rides up and down the center column. Two of those pulleys have anchor points attached to the lens stage and head, so by turning the wheels those stages can be moved up and down relative to the table. The third wheel turns a spool with a cable anchored to it on one end, and the column on the other. Turning this wheel will move the table up and down, but since the pulleys for the lens and head are also anchored to the table, those stages will also move with the table, (hopefully) keeping the image in focus while all three stages are moved up and down. The three moving assemblies (table, lens, and head) are all counterbalanced with weights in the pulley system. Most enlargers use constant force springs, but finding the correct tension springs for sale in the right lengths is expensive since I only need one of each, so I opted for counter weights instead. The counter weights will run through the tubes you can see anchored to the back of the column
Also, because I'm working towards building a trailer darkroom which won't be very large, I designed the table so that it can be folded up when not in use. I'm not certain that idea will work, it may make alignment difficult.
One of my goals for this was to make building it less expensive than buying the drop table for my DeVere, which would cost me around $2000. So far the chassis construction will cost about $1500 I believe, which leaves $500 left over for constructing an LED light source, which I believe will be doable. I've sourced most of the parts from McMaster-Carr, with the one exception being the linear bearings for the carriages. I found someone on eBay who sells plastic bearings which work with aluminum extrusion. They probably aren't as strong as the metal ones, but the cost is far less (metal ones would cost $750 for the amount I need) and because this enlarger is designed for an LED head which weighs far less than normal ones, I don't think it will be an issue.
I'm currently contemplating how I can build a mechanism for raising the head to allow for inserting a negative carrier. The two ideas I have are a cam mechanism like DeVere has, or a lever like omega and beseler use. Neither of those options seems great to me, so if you have any other ideas please share them!
Below are images of the whole construction, and the cable layout (which it seems is sideways, sorry!). I also included a link to my google drive where you can download the fusion 360 CAD file for the design, if you want to take a look at it. Because it's all made of aluminum extrusion and somewhat modular, it should be possible to change the head out for larger sizes, and with a DIY LED head, making it an 11x14 enlarger or some other ULF size shouldn't be that difficult.
https://drive.google.com/file/d/1KCu16rHMdFX_nCyEx6VpA52a0O7EA8pg/view?usp=sharing
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