g'day chris here, and welcome back to clickspring. i've just completed machining this piece of red morrel burl that i'll be using for the base of the clock. its a beautifully figured piece of wood, andi think an ideal candidate for a french polish. but i do need to do some work on the surfacefinish before i can get started. for the most part its a case of going overeach surface with fine grit abrasive paper, and filling the small cracks where necessary. the 2 large cavities on the underside i'llbe leaving as is. they're what remains of the original surfaceof the wood when the burl was harvested,
and i like the idea of them remaining in placeas a feature of that surface. the shellac solution can be purchased readymixed, but it's also quite easy to make a fresh batchfrom raw shellac flakes and denatured alcohol. in this case i'm making what is referred toas a "2lb cut" solution, which seems to be a good general purpose mix. check the description box below for some moreinformation on the quantities. the mix starts out quite thick, but afteran hour or so the shellac flakes fully dissolve, and the solution can be transferred to a moreconvenient bottle. i need a small amount of olive oil, to lubricatethe pad during the polishing process.
and for the pad itself a section of linen, and some cotton wadding that'll go insideto act as a reservoir for the polish. the shape of the workpiece means that i needaccess to both the sides and top as i polish, so i'm going to stand it off from the benchusing two sanding blocks, along with some double sided tape. it'll be firm enough to hold the work againstthe pressure of polishing, but will still be easy enough to separateat the end of the job. now strictly speaking the term "french polish"refers to the process of applying the shellac, rather than the shellac solution itself.
each wipe of the pad applies a thin film ofthe solution, and as the alcohol evaporates, the barest hint of a layer of shellac is leftbehind. its a slow and repetitive process, that graduallybuilds up the coating, layer upon layer. as the soultion starts to dry out, a small drop of helps to lubricate the surfaceof the pad. and with the pad now almost completely dry, that's where i'll leave it for this firstapplication. so after being left alone to cure for 12 hours,
the first application has shrunk considerablyonto the surface, and its ready for a second coat. again charging the pad with a small amountof shellac, and then lubricating with a drop of oil asthe friction increases. a good sign that all is going as it should, is a visible trail left by the alcohol asit evaporates. that trail gets shorter and the alcohol flashesoff faster as the pad continues to dry out. eventually, a shiny crust of shellac formson the surface of the pad, which makes its action across the surfacesleek and smooth.
it now becomes possible to burnish the surfacefor the first time. i'm pressing quite firmly here, and you cansee the sheen of the surface immediately start to improve. even with considerable pressure, the pad glidessmoothly over the shellac coating which is still soft and pliable, so it gives a little under the pressure, evening out the fine stroke marks and forminga more uniform surface. and then again, the shellac is given anotherperiod of time to cure. as the surface continues to develop over subsequentpolishing sessions,
i stop adding additional shellac, and insteadadd pure alcohol to the inside of the pad. this dissolves the residual shellac in thewadding, and so further dilutes the solution beingapplied. and with the completion of this third polishingsession, i'm going to leave the top surface as it is, and give it a light wipe with a dry pad toremove the majority of the oil. another 12 hours of curing, and then i cansafely flip the workpiece and apply a similar coating to the other surface. the process can be continued for as many sessionsas desired,
but with this underside surface starting tolook presentable, i'm calling the job done for now. once all surfaces have been allowed to cure, a small amount of lighter fluid on a cleancloth can be used to clean off the last of the oil, and at this point finish really starts tojump out, particularly under bright lighting. now there's no avoiding the fact that thisis a very time consuming process, and i guess for that reason alone french polishinghas largely been replaced by more convenient wood finishing processes.
its reasonably fragile and susceptible tobeing marked by water and alcohol. but its also quite easy to repair, and fora cheap, environmentally friendly, and thoroughly traditionalwood finish, its certainly hard to beat. thanks for watching, i'll see you later. and if this is your first clickspring video,welcome. you've just been watching what i call a spareparts video. a short video, related to a much larger multiepisode project series, where i show all of the steps to make a mechanicalclock from raw metal stock,
so be sure to subscribe and check out thoseother videos. if you'd like to help me bring you more projectvideos like this one, then consider becoming a clickspring patron, as a patron of the channel you get accessto exclusive patron only video content, free plans for the patron projects, and the chance to win the actual project atthe end of each build. like for example this useful little hand vise. find out more by visiting patreon.com/clickspring thanks again for watching, i'll catch youon the next video.