6ft Straight Edge Hand Scraping
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- เผยแพร่เมื่อ 10 ธ.ค. 2018
- Bringing back an old 6ft Camel Back Straight Edge into working condition by hand in a small workshop without a huge granite plate or 6ft master. Making use of all we have learned over the past months and the Straight Edges resurfaced to date.
For those new to scraping, check out the threads on the forum of Practical Machinist on machine refurbishment & scraping - there is a huge amount of information, knowledge and experience to be gleaned. Search TH-cam for Hand Scraping, Bearing Scraping and similar - there is an ever growing list of videos - some better than others.
I am self taught, mainly from doing, advise of others and from watching YT videos - I have poor practices and am addressing these slowly, so be careful what you take on board and what you leave behind !
I hope that you gain something from watching, maybe others will produce better videos on the subject as a result of the issues I show in this and that truly would be a good thing to help get the knowledge out into the public arena where it can be used.
Thanks for watching, do take a look through my earlier videos - the early scraping videos contain a lot of information I picked up and they point to the sources, these later ones tend to take for granted that you have watched these (my bad !).
All the best
Mat
Enjoyed Matt!
ATB, Robin
Boy you certainly have some patients, great explanation of how your working through this Mat, I know it’s a bit away yet but I’m looking forward to seeing you scrape the lathe in.
Regards Alan.
Love what you doing.Look like almost impossible job, your master is shorter than your work. Never seen this before.
Thank you to film this! It has certainly been a very tasty case ... I liked very much!
Thank you for stopping by and watching. I am very glad you enjoyed it. All the best Mat
Nice job Matt 👍
You are one determined SOB, I admire it :). Kudos for British ingenuity, You managed to make a mojito with lemons handed to you. By no means, this should be considered the "way" to do a proper reconditioning, but you managed to get it in alignment without a master larger than what you are scraping. based on the previous discussion on PM, I think your method is sound, and I like the way you verify your assumptions. I never went behind a 25% discrepancy between master and target size., You are a brave man going from 2-foot reference to a 6-foot target. I also like the way you manage to laugh at your mistakes....
Hi Dee, thanks for stopping by and thanks again for the comments. I think this SE re-scraping project has been a hell of a challenge for me. The discussions on PM gave me lots to think about and I hope to cover some of the ideas presented there in my update video. The 'twist gauge', averaging out approach and then I guess ultimately the codged together approach I took and why. There's no way I would recommend this approach unless you have (as me) explored the other approaches including beg/ borrow or buy a master to work from etc etc. In the end we have to find a solution that can be achieved in our shops with what resource we can get a hold of. I have no way of confirming the 'incremental error' from my approach - an autocollometer would help ! - as things stand, I have checked everything I can at each stage and with different equipment . Interestingly, the 5'6" light weight SE I am working on to use on the lathe re-scrape - using this 6ft as the master - now I have the light weight SE 'flat' and hinging correctly on the master - it repeats end to end and up and down the master - so what ever error is there has to be small by my thinking. All the best Mat. (P.S. 'Determined SOB' - imagine what I could achieve if I knew what I was doing !
@@lookcreations Hi Mat, I meant the post as a warning to others who may want to follow your method, use it only as a last resort, it is not for the faint-hearted, You researched, thought it through and made it work for your situation. It is not directly transportable to any other situation without modifications. The real value here is your description of how you solved each problem. It is a well-documented step by step on how to make your tools work for what you are faced with. Some of the things you came up with are just brilliant, some of them are hmm that is curious. I appreciate that I learned from this video a bunch of things I would not even try without having it seen first.
@@unclespicey42 I think you put that pretty well Dee. I may add the 'health warning' up front :-) there were times during the long hours it took when I very much felt like chucking the thing down the workshop... had it been lighter and more easily hurled ! I tried to include as much info' on my thought process as possible as quite frankly my skills are not so good. Im still trying to get fully conversant with curling to get the best from it. I am hoping that my friend Chris will call in to the shop in the near future and give me some pointers. What I have determined is the cheep carbide blanks I've been using are not too good at holding a crisp edge for long - I have to re-hone 4 or 5 times for a single pass as a minimum - the consequences of not maintaining a crisp edge result in more effort required and thus less control of the scrape. Less control gives greater variation in depth of the curls. Its a fundamental difference in the style of scraping - something else I will discuss in the follow up . So next task is making up a shorter scraper to take a sandvic blade and see how that works for me. I know this 'curling' is not everyones cup of tea and its not really the point of this video - it has made the task more complicated for me and at the same time made me appreciate the simplicity of the commonly used push & return straight scraping. I think each has its merits - in my limited experience the loudest voice usually carries furthest but is seldom the best nor only way. At some stage I may have a go at pull scraping a small surface plate - for shits and giggles as they say :-) best of health to you Dee. mat
Great work!
Thanks!
@@lookcreations I'll need to follow this series to get up to length for a bridgport rebuild. I only have a toolmakers sized granite.
Well done
thank you ;-)
Like your scraping videos, I have watched all of them. One thing i observed is you clamped both ends to the saw horses which may induce a twist.
you might clamp only one end and side block the other end and allow it to float. there by not inducing any torsional in the straight edge
keep uy the swell videos
Hi Wayne, thanks for stopping by and watching and leaving a comment. I will try and put together a ' directors cut' of out takes from the 6ft re-scrape as I did cover this. You are absolutely correct about inducing a twist if the clamping is not correct. I had one clamp come loose mid scrape - I reached down nipped it up lightly and carried on scraping off the blue. Next print / rub and the distribution was completely different - I knew something was wrong. It took two more print attempts, lots of cleaning off until I found the problem. I really appreciate these comments as anyone that reads them can extract useful info' . Thanks again. Mat
👍👍👍
This looks very hard to work out, I would be hopeful it prints the same when used the correct way up with the weight distribution in the long centre line, I have no experience doing anything like this but it looks like you need to know the black arts to get it wright.
It takes some skill and knowledge to get it right, a poorly designed and made straight edge will never be a precise tool. But a well designed and made bone can be incredibly accurate in the right hands.
Mat I am looking at this in Jan 2021 . Where did you get the carbide strip from? I can only find one source of carbide and it's a scraper blade of I think 40 wide by 25 by 4 mm and it's nigh on eighteen quid a throw! So your source of carbide strip would be most helpful mate. Many thanks!
Drop me an email - I will try and help you out. Mat
What are you using this to measure/test?
First job is to use it to scrape in a lightweight 6ft SE to use on my lathe bed re-scrape - the plan is to alternate the narrower 6ft light weight SE end to end and corner to corner - it should help identify any remaining issues with this SE. I am fairly confident now that I have this SE flat. The 24" prints repeatably over the entire surface.
...wow, what a pain.
Hi Mat, I guess you already have taken this in account, when using the spirit level, be sure that it has not "bottomed out" to the side, it has bitten me once or twice, in particular when using my 0.02mm/m square level. All the best. BTV have you seen this video : th-cam.com/video/t0gg9z4gG3A/w-d-xo.html , some dining table, I think they are not bluing but abrasive and then looking for the shiny spots, strange that hey have supported it in 3 points but not in either airy or bessel points, unfortunately there are no English subtitles.
Jesus !
You lost me.
How do you keep your focus Matt ?
I think I am going to leave my "new" 1944 Colchester as is and work around any issues I may find.
What is father Christmas bringing you ?
Hi Steve, focus - I spent 20 years working in Tibet with the monks - seeking a higher plane ....... :-)
In fairness, I scrape until I'm tired, need a break or cheesed off then walk away for a few hours or day off. I can't get a good result if my minds not on it - all the normal factors tend to draw away my attention so I get to sort them out first - kids, partner, dog etc etc. I suspect father Christmas has listened to my language and placed me in the naughty pile ! Thanks for watching and commenting Steve - I will put a short review togther later this week and discuss the lessons learned and experience gained thus far - might help others you never know ! ATB Mat
@@lookcreations
Nommmmm
Nommmmm
(Budist chanting)
If you have the same relationship as I have with my dog (I think you do) he / she helps keeps you sane.
@@stevewilliams587 I second that.