For the better part of two years now, Jay and I have been discussing the best way to approach updating our frame table to significantly improve its accuracy, range of capabilities and reduce job set up time, calibration needs, etc. Basically, we were trying to decide what the best approach for US was to build a killer frame table. Something that would allow us to not only do frame modifications like hard-tails, but build complete one-off frames, fix bent or broken frames with accuracy and reliability, and who knows what else.
After going back and forth with different design ideas ranging from rotating Blanchard ground I-beams with CNC dilled and tapped holes, to adapting pre-fabed fabrication tables, we settled on a mix of both: buy some already available, highly precise components, and “meld” them into a form that suited our needs.
It became clear that the common T-Slot table was a perfect foundation for what we wanted to do. Not only do they allow for ease of adjustability, there are a myriad of fixture related fastening systems already available for them. (This point, while not as exciting as making every last part, helps save us time and money.) The trick was finding a large enough t-slot table to suit the job….. After a few months of watching craigslist and eBay.. I found a 75” x 25” T-Slot table off of some forgotten American made monster of a milling machine, and I had to pull the trigger. Something about knowing the table was saved from the scrap yard and that it would be put back to use in a metal shop made me feel really good about spending the cash… And at a dollar a pound shipped, I felt like it was a pretty fair deal.
When the table arrived, the design for the whole set up really came into focus. We happened to have a “spare-parts” Bridgeport, so I “robbed” the t-slot table off of that machine to use for the front vertical axis of the table… and planed to do something similar for rear axis, for locating the rear axles.
But first, we needed to handle supporting our new frame table….all 1300lbs and counting of it….
So in the spirit of overkill, (why stop now?!) I ordered up some 3” x3” x .25” wall square tube. Yes, ¼” wall box tube, and fashioned a very nice, compact but purpose driven stand for the table set up. Considering that the t-slot table was designed to support itself and maintain flatness without a full bottom support, you can start to see just how overkill the stand is… but we like to know that we will never have to worry..ever…. I cut all the tubing on our cold saw, cutting all the individual parts before doing any assembly. The frame was clamped and welded on the t-slot table itself, since it was a dead flat surface of the right size. I very easily could have MIG welded the whole thing together, but in the interest of over-complication and also because I just really like they way it looks, I TIG welded the whole stand. Root passes with weaved caps in the natural “valleys” created by the shape of the tube, and just burned in singles passes on the butt welded edges. For the lower supports I incorporated a single shelf for storing motor dummies, fixture parts, tools, etc.
Once the stand was welded up, I welded on some leveling casters that are rated to 800lbs each. This way the table would be semi-mobile, but we could level it up wherever it ended up.
Because the lower, flat t-slot table and front, vertical t-slot table are different size tables, they also have different size t-slots, in terms of their width. (The lower table slots are 11/16” wide, the vertical table slots are 5/8”) As the design calls for the centerline of the smaller vertical slot to align with the centerline of the larger flat t-slot table, the next step was machine up a block that located the upper table to the lower table. To do this, we milled up a chunk of aluminum to the respective proper sizes and tapped it in. Once that was in place, we clamped both tables together using a high-tolerance precision ground cast iron angle plate that is a true 90 degrees. This, after double checking, effectively gave us two perfectly perpendicular work surfaces with totally aligned center lines.
This concept of alignment blocks plays into the design of the rest of the table components, because now that we know the tables are locked into place, we can count on them staying that way, and hold tolerances well within the requirements of the demands we will place on them.
The neck location component was the next step. After purchasing a solid start from the chop-cult classifieds, we made a self-locating base-plate out of a flat steel plate and a section of aluminum milled to fit the vertical t-slots. We then welded the neck pin to the base plate, being sure to maintain alignment through clamping and stitch welding slowly.
Once installed, the neck component was checked for proper alignment first with the low-tech string method, and then with a high-precision laser. Both confirmed that all our parts were lined up. We still need to make the axle location components, as well as motor and Trans location components, but those projects are for another time….
So I know what you’re all thinking, and yes we know this table is far more than it needs to be. Could you build a different but still perfectly useable, accurate frame table? Absolutely! This is just how we wanted to do ours…recycling some old American Iron and incorporating it into a table that is totally bullet-proof. It’s just our take on solving the issue of how we can do frame work better, faster and in the long run, for less of your dollars and so we can do some crazy personal projects! Some items already on the chopping block: a bent Evo sporty frame repair, Jays Buell Project, my Knuckle Land-speed Frame, and a Shovel hard tail project… so keep an eye out for those!
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