TheCoatingStore.com

Results 1 to 15 of 36

Thread: Advice / Help with Shaping?

Hybrid View

  1. #1
    Join Date
    Apr 2021
    Posts
    15

    Default Advice / Help with Shaping?

    Hi there guys – I have been reading and searching this forum with great delight, so much information on here about autobody 😊 So this is my first post and it is for help or more to the point what I am doing wrong...

    In short I have a handmade fuel tank, it was taken back to almost bare metal by me. I am getting a little stuck, mostly around shaping Filler. Have been applying Indasa Autofill filler on most of the tank to get me my rough shape before I go onto the easy sand filler (Upol Fantastic Filler). At the moment AutoFill is all I have been applying to the tank..

    I have the Durablock set (various shapes and sizes and some Soft Sanders also. Various grades of sandpaper, I have been mostly shaping with 60 grit by hand and some 80 grit on a DA. I bought a compressor and DA for this job and eventually this setup will be used for painting when I get to it.

    Fast forward 10-11 months into my attempt to do this myself so I apologize in advance if I have missed anything.

    I have been sanding mostly in criss-cross / diagonals, short and long sweeps. Now one bit I have plateaued on and its kind if difficult to explain is I seem to have two opposite corners that are a little ‘off’ or lower/less curved/more curved as opposed to the other two opposite corners when l look from certain height or angle. I feel like I am chasing curves and not getting anywhere (that probably does not make sense). Making simple cardboard cutouts of one side and flipping it over do not seem to work in my favour either.

    I am also not sure if I have inadvertently spent too long Sanding on one side of the tank making it look a little off shape or perhaps I have applied too much or little filler on some areas and not enough on other parts of the tank which could be what is making it look slightly off. I work on the tank when I have spare time, it is not continuous unfortunately as some days are but mostly its gaps between working on it.

    So my question is really, is there a technique that I am missing or is it a case of keep sanding until the desired shape is achieved using 60 and then 80 grit? Photos will probably explain a lot more hopefully. I shall try by best not to give up 😊 Any advice would be greatly approached!

    Many thanks,
    VJ
    Attached Images Attached Images

  2. #2
    Join Date
    Nov 2005
    Posts
    47,716

    Default

    Be sure that you use a "guide coat" for helping adjust for surface irregularities. Also, once you get the shape corrected and you're ready to block the minor variations use a "good" spray-on filler like Slick Sand or Optex and again use a guide coat to help achieve perfection.


    Slick Sand can be sanding with some 220 to 400 before applying a 2K filler primer then guide coated and block sanded using 400 to 600 wet then you're ready for color.

  3. #3
    Join Date
    Apr 2021
    Posts
    15

    Default

    Hi Len - thanks for replying back so promptly!

    I have guide coat (dry powder only) however not used it much thinking it is too early in the stage?! Thinking now guide coat can be used anytime right when blocking? I did briefly use guide coat… it sanded away really quick after a few hits of 60g.

    Question, is there a specific way to blocksand curves, concaves, convex shapes? I feel I cannot bring both sides down equally for some reason. I have bought 2k epoxy and spray on filler ready for when its needed, clearly a long way off applying this stuff.

    I have attached a couple more photos of how the tank is now (actually a few weeks back) and how the tank used to look like. The tank does not sit level so have to prop it up slightly from one corner to get it level.

    Many thanks again,
    VJ

    thumbnail_DSC_3215_resize.jpg


    tank_finished.jpg

  4. #4
    Join Date
    Nov 2013
    Location
    olympia,wa
    Posts
    2,113

    Default

    getting round things flat can be very challenging. you will probably find the dura blocks will be too stiff for the tight radius sections you're working on. i keep a bunch of different hardness rubber blocks, long skinny ones, short fat ones, all different shapes and sizes. you need them to conform to the surface, but still be stiff enough to cut the high spots and not just conform to the irregularities you're trying to eliminate.
    b marler

  5. #5
    Join Date
    Nov 2005
    Posts
    47,716

    Default

    On a shape like that I would normally sand at an angle around the shape. When sanding a guide coated filler be sure to sand on the high spots and NOT sand on the low guide coated areas. Sand on the high spots until they are level and the guide coat disappears.

  6. #6
    Join Date
    Apr 2021
    Posts
    15

    Default

    Hi there b marler – you are spot on about the dura blocks being a bit stiff. I do have the round and the slim palm size dura block, which are not that rigid. These came as a dura block set, would this work? Any chance you would have a link to where I could get some of the rubber blocks from, did you make them yourself? I have a pack of soft sanders which are really soft, these have not worked that well for me, maybe later on after the high build stage these could come into use.

    Hi Len – I got you, I shall bring the surface down using guide coat and not labour on the low areas. It is difficult to have to think about every stroke I must admit… sand at an angle and around… repeat sand at an angle and around… and so on… get this into muscle memory and I will be a pro in no time he say

    VJ

  7. #7

    Cool

    Quote Originally Posted by bmarler View Post
    getting round things flat can be very challenging. you will probably find the dura blocks will be too stiff for the tight radius sections you're working on. i keep a bunch of different hardness rubber blocks, long skinny ones, short fat ones, all different shapes and sizes. you need them to conform to the surface, but still be stiff enough to cut the high spots and not just conform to the irregularities you're trying to eliminate.
    Then make them unstiff

    IMG_2139.jpg
    IMG_2140.jpg
    IMG_2138.jpg
    IMG_2137.jpg

  8. #8
    Join Date
    Apr 2021
    Posts
    15

    Post

    How did you do that, did you cut those slots in yourself by hand? My skills are limited to what I know which is pretty much nothing, reading threads on this forum is where my learning curve starts

    Your ones look really good, can you still use them on flat parts perfectly fine? Thinking why Dura Blocks never made them with slots from factory.

    I have ordered Motor Guard MB and SB hand blocks also which are softer than the dura blocks I currently have. Having the right tool for the job eh, my wife thinks everything that comes in for me is £12 and bought really cheeeepp, like the budgie...

    VJ

  9. #9
    Join Date
    Nov 2013
    Location
    olympia,wa
    Posts
    2,113

    Default

    Quote Originally Posted by MidnightOilJK View Post
    Then make them unstiff
    i love that. i love when someone points out something so simple that you think to yourself, how can it be that i never thought of that?
    thanks for posting.
    i'm assuming you cut those on a table saw right?
    b marler

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •